Volume 12 (2014)
  Number 3

Journal full text: Vol 12 No 3 689-834 , 835-1008

Contents


Pages

695-704 M. Ahokas,, A.-L. Välimaa, T. Lötjönen, A. Kankaala, S. Taskilaand E. Virtanen
Resource assessment for potato biorefinery: Side stream potential in Northern Ostrobothnia
Abstract |
Full text PDF (356 kB)

Resource assessment for potato biorefinery: Side stream potential in Northern Ostrobothnia

M. Ahokas¹,³⋅*, A.-L. Välimaa¹, T. Lötjönen², A. Kankaala¹, S. Taskila³and E. Virtanen¹

¹MTT Agrifood Research Finland, Biotechnology and Food Research, P.O. Box 413, FI90014 University of Oulu, Oulu, Finland 2MTT Agrifood Research Finland, Plant Production Research, Tutkimusasemantie 15, FI92440 Ruukki, Finland 3University of Oulu, Chemical Process Engineering, P.O. Box 4300, FI90014 University of Oulu, Finland; *Correspondence: mikko.ahokas@oulu.fi

Abstract:

Potato industry side-streams consist of a significant amount of the original biomass. However, tightened demands of EU legislation together with the costs of side stream processing have forced potato industry towards more efficient use of the raw material. For this purpose, we have examined the possibility to recover main fractions from potato side streams, such as proteins, fibers and starch, and utilize them in a manner of biorefinery concept. The aim of the present research was to evaluate the potential for a potato biorefinery based on biomasses available at area of Northern Ostrobothnia, Finland. Study shows, that there is enough side-streams available to build a concept, which produces more value added products, like fibers and proteins. In this report, the main conclusions of the research are presented together with state-of-art on potato waste water processing technologies and current applications of their products.

Key words:

, , , , , ,




705-716 D. Baranenko, V. Kolodyaznaya and Y. Broyko
Effect of cold treatment on the amino acid composition of veal
Abstract |
Full text PDF (309 kB)

Effect of cold treatment on the amino acid composition of veal

D. Baranenko*, V. Kolodyaznaya and Y. Broyko

Institute of refrigeration and biotechnologies, ITMO University, 191002, Lomonosova Street 9, Saint-Petersburg, Russia; *Correspondence: denis.baranenko@gmail.com

Abstract:

Veal is a promising raw material for use in the daily diet, as well as for production of functional and dietary foods. However the effect of cold treatment on the amino acid composition of veal has not been sufficiently studied. The aim of this study was the amino acid composition analysis of veal subjected to various variants of cold treatment. The selected material under research was muscle tissue of hip parts from calves, grown in the Leningrad Region, Russia and aged no more than 3 months. Cooling to 4 ± 1°C and rapid freezing to the temperature of minus 18°C at the cooling air temperatures of minus 24°C and minus 35°C were used as variants of cold treatment. Amino acid composition analyses were carried out using precolumn derivatization with phenylisothiocyanate and reversed-phase gradient HPLC on the Shimadzu 20-AD chromatograph with spectrophotometric detection at 254 nm. The results show the effect of cold treatment on the content of free amino acids and total amino acid composition of veal. In many respects changes in amino acid composition are concerned with moisture losses during the refrigerating treatment. The dependence between the change in amino acid content and the structure of its side chain group type is shown. Amino acid score for essential amino acids was calculated and conclusions about changes in biological value of veal protein were made. The obtained data can be used in biological value calculation of the multi-component products and food rations with veal subjected to refrigerating treatment.

Key words:

, , , ,




717-726 N. Iakovchenko and L. Silantjeva
Vegetable ingredients in soft cheese made from concentrated skim milk by ultrafiltration
Abstract |
Full text PDF (411 kB)

Vegetable ingredients in soft cheese made from concentrated skim milk by ultrafiltration

N. Iakovchenko* and L. Silantjeva

Institute of Refrigeration and Biotechnologies, ITMO University, Lomonosova Street ⁹, ¹⁹¹00², Saint-Petersburg, Russia; *Correspondence: frack@mail.ru

Abstract:

The objective of this research was to develop the technology and composition of soft cheese made from concentrated skimmed milk by ultrafiltration with a low concentration factor. UF enables reduction in the quantities of starter, rennet, colorants, and cheese making costs per vat. The use of UF milk appeal to lactose intolerant consumers because of the low lactose levels in the product. Ultrafiltration was carried out using polyethersulfone membranes. Jerusalem potato and carrot were chosen as vegetable ingredients. Since the soft cheese was made from skimmed milk retentate, there was a necessity to compensate the lack of fat. In this research the impact of orange fiber on organoleptic qualities was determined. For imparting mouthcoating, creaminess, and providing for an even meltaway effect in the mouth CITRI–FI ¹00 FG (pure orange fiber), CITRI–FI ²00 FG (orange fiber with guar gum), CITRI–FI ³00 FG (orange fiber with xanthan gum) were chosen. Application of CITRI–FI ²00 FG and CITRI–FI ³00 FG enables the production of high quality curd only up to certain concentrations, which do not have a significant impact on the organoleptic qualities of soft cheese. The use of CITRI–FI ¹00 FG enables to get firm curd and can at the same time create organoleptic properties of a fat-containing product in the finished soft cheese. Thus, on the basis of data CITRI–FI ¹00 FG is recommended to use for manufacturing soft cheese where mouthfeel is needed. Optimal concentrations of CITRI–FI ¹00 FG were determined.

Key words:

, , , ,




727-736 L. Kuznetsova, L. Zabodalova and D. Baranenko
On the potential of lupin protein concentrate made by enzymatic hydrolysis of carbohydrates in dairy-like applications
Abstract |
Full text PDF (441 kB)

On the potential of lupin protein concentrate made by enzymatic hydrolysis of carbohydrates in dairy-like applications

L. Kuznetsova*, L. Zabodalova and D. Baranenko

Institute of Refrigeration and Biotechnologies, ITMO University, Lomonosova Street ⁹, ¹⁹¹00², Saint-Petersburg, Russia; *Correspondence: mamaeva.ludmila@mail.ru

Abstract:

The aim of this research was to study the parameters of obtaining lupin concentrates by enzymatic hydrolysis of wholegrain lupin flour and application of these concentrates in the technology of high-protein dairy-like products. The following enzymes preparations were used: Celluclast BG, Cellulaza ¹00, Pentopan Mono BG and α-amylase. The usage of Cellulaza ¹00 and Pentopan Mono BG showed the highest protein amounts in the lupin concentrates under the test conditions. Three factors were studied to take effect on crude protein content in the product: temperature in the range ⁵0–⁶0°C; cellulase dosage between 0.⁵⁴–¹.⁶² units g-¹; ratio water: flour – ¹0 : ¹, ¹⁵ : ¹, ²0 : ¹. Optimum hydrolysis conditions for Cellulaza ¹00 were temperature of ⁵⁵°C; ratio water: flour of ¹⁵ : ¹; cellulase dosage of ¹.0⁸ units g-¹. Crude protein content in the final product increased on ¹²% compared with the original flour and on ⁸–⁹% compared to the lupin concentrate obtained without enzymes. Hydrolysis by multienzymatic compositions was tried as an alternative way of increasing the efficiency of the process. However hydrolysis by multienzymatic compositions was not yet found so efficient as hydrolysis by pure Cellulaza ¹00. The lupin protein concentrate was dispersed in water and mixed with skimmed milk to have total product protein content about ⁵%. The mixture was fermented by yogurt starter culture; consumer properties of final products were investigated. Fermented products supplement the diet with vegetable proteins, fats, carbohydrates and fiber, which have high biological value.

Key words:

,




737-744 T. Michlová, Š. Horníčková, H. Dragounová and A. Hejtmánková
Quantitation of vitamins A and E in raw sheep milk during lactation period
Abstract |
Full text PDF (334 kB)

Quantitation of vitamins A and E in raw sheep milk during lactation period

T. Michlová¹, Š. Horníčková¹, H. Dragounová² and A. Hejtmánková

¹Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, the Czech Republic 2Dairy Research Institute Ltd, Prague, the Czech Republic

Abstract:

In this article, the influence of breed and lactation stage on vitamin A and E content in raw sheep milk was studied. The milk of the East Friesian, Romanov and Lacaune sheep breeds was included in the study. The samples were taken once a month throughout lactation. The total average content of vitamin A in raw milk of all sheep breeds during lactation was 0.76 ± 0.19 mg kg-1 of milk and the total average content of vitamin E was 2.86 ± 0.99 mg kg1 of milk. The content of vitamin A and E during lactation varied in respect to the breed type. The highest average content of vitamin A and E was detected in the Romanov sheep:1.01 ± 0.19 mg kg-1 of milk for vitamin A and 4.26 ± 1.90 mg kg-1 for vitamin E. The lowest average value of vitamin A was found in the milk of the East Friesian sheep (0.56 ± 0.10 mg kg-1). This milk showed also the lowest content of vitamin E 2.11 ± 0.53 mg kg-1. The highest content of vitamins was found in summer and at the end of lactation, which is in September, and the lowest values appeared in early lactation, which is in April.

Key words:

, , , ,




745-752 U. Moor,, P. Põldma, T. Tõnutare, A. Moor and M. Starast
The effect of modified atmosphere storage on the postharvest quality of the raspberry ‘Polka’
Abstract |
Full text PDF (393 kB)

The effect of modified atmosphere storage on the postharvest quality of the raspberry ‘Polka’

U. Moor¹,*, P. Põldma¹, T. Tõnutare¹, A. Moor² and M. Starast¹

¹Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, EE5104 Tartu, Estonia; *Correspondence: ulvi.moor@emu.ee 2Institute of Economics and Social Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, EE5104 Tartu, Estonia

Abstract:

The aim of the experiment was to determine the effect of a passive modified atmosphere package (MAP) (30 m LDPE bag (Estiko, Estonia), the Xtend® raspberry bag (Stepac, Israel) and an active MAP (30 m LDPE bag, flushed with a gas mixture containing 10% O2 and 15% CO2) on the postharvest quality of the raspberry ’Polka’. Raspberries stored in macroperforated punnets (normal atmosphere – NA) served as the control. The raspberries were initially stored for 3 days at 1.6°C, then a half of the bags were moved into simulated retail conditions (6ºC) and a half remained at 1.6°C for another 24 hours. The raspberry weight, O2 and CO2 content of the packages were measured daily. The fruit dry matter (DM) and soluble solids content (SSC), titratable acidity (TA), ascorbic acid content (AAC), and total anthocyanins (ACY) were determined at harvest and the total antioxidant activity (TAA) and rotting (weight of rotten berries) were determined after storage. Neither the active nor passive MAP suppressed rotting significantly. The raspberries stored at 1.6°C, had the best quality in passively modified LDPE bags, since the fruit had higher SSC and TA and lower ACY content compared to the control. After the simulated retail conditions, the Xtend® bags turned out to be the most suitable, since the fruit had the lowest ACY content (the fruit did not become too dark), but the highest TAA. Key words: Rubus idaeus, soluble solids, titratable acids, ascorbic acid, anthocyanins, total antioxidant activity.INTRODUCTION

Key words:

,




753-758 H. Mootse, A. Pisponen, S. Pajumägi, A. Polikarpus, V.Tatar, A. Sats andV. Poikalainen
Investigation of Casein Micelle Particle Size Distribution in Raw Milk of Estonian Holstein Dairy Cows
Abstract |
Full text PDF (343 kB)

Investigation of Casein Micelle Particle Size Distribution in Raw Milk of Estonian Holstein Dairy Cows

H. Mootse*, A. Pisponen, S. Pajumägi, A. Polikarpus, V.Tatar, A. Sats andV. Poikalainen

Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Kreutzwaldi 56/5, EE51014 Tartu, Estonia; *Correspondence: hannes.mootse@emu.ee

Abstract:

The particle size of milk influences its microstructure and defines many properties of dairy products such as colloidal stability, texture etc. Differences in particle size can significantly affect milk processing especially when membrane technology is used. Aim of this investigation was to estimate casein micelle size in the raw milk of Estonian Holstein dairy cows and its variability concerning individual animals. Milk samples were collected during 12 months with the interval of 25–35 days. DLS analyses were performed using a Malvern Zetasizer Nano ZS (Malvern Instruments Ltd, Malvern, UK). Average mode of casein micelle particles size in raw milk of 44 cows was 171.13 nm with the variation range 70.1 nm and its distribution resembled a normal one. Casein micelles size mode of individual cows varied in a wide range from 148.5 (with variation range 18.2) to 194.1 (with variation range 27.6) nm which may be caused by differences in physiological and health status, stage of lactation and other factors concerning milk production.

Key words:

, , ,




759-768 L. Nadtochii and A. Koryagina
Fermented sauces for child nutrition from age three
Abstract |
Full text PDF (325 kB)

Fermented sauces for child nutrition from age three

L. Nadtochii* and A. Koryagina

ITMOUniversity,Lomonosova Street 9,191002Saint-Petersburg,Russia;
*Correspondence: l.tochka@mail.ru

Abstract:

One of the directions in modern food science is the development of diets for children of different age groups based on their physiological needs and psycho-emotional activity. One of the approaches to solving this problem is functional product design. Such products are not medicaments, but help to prevent the diseases and ageing processes of the human organism. The purpose of our research was to develop fermented sauce compositions based on milk and plant ingredients for child nutrition. Mass fractions of pumpkin and banana purée, berry syrup and stabilizing additives were experimentally determined. Key words: Fermented sauces, child nutrition, fruit and vegetable purées, berry syrups, corn starch.INTRODUCTION

Key words:




769-778 O. Orlova and U. Nasonova
The unique characteristics of milky-wax ripe walnuts and their usage
Abstract |
Full text PDF (337 kB)

The unique characteristics of milky-wax ripe walnuts and their usage

O. Orlova* and U. Nasonova

Institute of Refrigeration and Biotechnologies, ITMO University, Lomonosova Street ⁹, ¹⁹¹00² Saint-Petersburg, Russia; *Correspondence: oousova@list.ru

Abstract:

The objective of the research is to obtain biologically valuable and safe food products, which have functional qualities and extended shelf life by using the antimicrobial properties of walnuts and walnut leaves of milky-wax ripeness. A study was conducted on the possibility of using walnuts of milky-wax ripeness (walnut materials) in the production technology of functional foodstuffs (cheese products, beverages, cheese, desserts, and bakery products). The study identified types and possible amounts of walnut additives into the developed products. Various additives were obtained during the research, such as extracts, tinctures, dry powders, and capsules. The most unique specific substance in raw nut is juglone. Juglone is a natural antibiotic that inhibits more than ¹00 kinds of pathogenic microorganisms. The developed products with the addition of walnuts and walnut leaves of milky-wax ripeness contain high amounts of vitamins (especially C, E, A, and group B) and minerals (iodine and manganese). For this reason, walnut contains the natural antibiotic juglone, which increases the shelf life of products up to ²¹ days without the use of stabilizers or preservatives. Because of the multifunctional properties of raw nut, more specifically the antibacterial, fungicidal and preservative properties of juglone, the additives ensure a sustainable microbiological state of the products. Juglone allows sparing technological heat treatment of raw milk (⁴0 ± ²°C) that reduces energy costs for the operation and the equipment. Various population groups can successfully use the designed products as functional food; what is more, they can be used for medical purposes. Key words: Walnut, fermented products, dairy products, juglone, preservative, milky-wax ripeness.INTRODUCTION

Key words:

, ,




779-786 A. Pastukhov, and H. Dogan
Studying of mixing speed and temperature impacts on rheological properties of wheat flour dough using Mixolab
Abstract |
Full text PDF (512 kB)

Studying of mixing speed and temperature impacts on rheological properties of wheat flour dough using Mixolab

A. Pastukhov¹,* and H. Dogan²

¹ITMO University, Institute of Refrigeration and Biotechnologies, 191002, Lomonosova Street. 9, office 2111 Saint-Petersburg, Russia; *Correspondence: artem.pastukhov1984@gmail.com 2Kansas State University, Department of Grain Science and Industry, 201 Shellenberger Hall, Manhattan, KS 66506, KS, USA

Abstract:

Wheat flour dough is highly non-Newtonian, time-dependent, strain-dependent and viscoelastic. These rheological properties are very sensitive to temperature, water content and composition. Dough mixing is one of the most important ways to characterize the quality of wheat flours. Proper dough development is affected by mixing intensity (mixing speed) and work imparted to the dough. The objective of this research was to study impact of mixing speed and temperature on thermomechanical properties of breadmaking quality wheat flours using Mixolab. Analysis was carried out at the constant water absorption (98% db) using standard Chopin+ protocol, which consisted of a heating/cooling cycle after a certain mixing time at constant mixing speed (60–120 rpm). Effect of temperature at 80 rpm, 100 rpm, 120 rpm, and effect of mixing speed at 30°C, 40°C, 50°C were also studied. Strong relationships were observed between the mixing speed (rpm) and the Mixolab parameters (dough consistency during mixing (C1), mixing stability, protein weakening (C2), starch gelatinization (C3), amylase activity (C4) and starch gelling (C5). Mixing temperature was observed to have higher impact on dough consistency and stability than mixing speed. Softening effect of temperature was more significant at low mixing speeds.

Key words:

, , ,




787-792 A. Pisponen, S. Pajumägi, H. Mootse, A. Sats, V. Poikalainen and A. Karus
Effect of cooling rates and low crystallization temperatures on morphology of lactose crystals obtained from Ricotta cheese whey
Abstract |
Full text PDF (564 kB)

Effect of cooling rates and low crystallization temperatures on morphology of lactose crystals obtained from Ricotta cheese whey

A. Pisponen*, S. Pajumägi, H. Mootse, A. Sats, V. Poikalainen and A. Karus

Department of Food Science and Technology, Estonian University of Life Sciences, Kreutzwaldi 56/5, EE51014 Tartu, Estonia; *Correspondence: anna.pisponen@emu.ee

Abstract:

In the traditional process of lactose production from cheese whey crystallization temperature is reached by slow cooling. Lactose morphology obtained in this way has been well investigated. The objective of this work was to study morphological parameters of lactose crystals during crystallization at low temperatures, using rapid and extra rapid cooling. Ricotta whey was chosen for analysis because this raw material has been poorly investigated as a source of lactose production. Three temperatures (2, 6 and 12°C) were used for crystallization of lactose. Rapid (0.5°C min-1) and extra rapid cooling (3°C min-1) rates were used to achieve these temperatures. Dimensions of crystals were examined with optical stereo-, and scanning electron microscopes. Pure lactose solution was used as a reference during the study. The results of the study showed the impact of some Ricotta whey components on the crystals morphology and size. These components reduce crystals size, and linked with low crystallization temperature, modify the shape of crystals faces. Extra rapid cooling of Ricotta whey contributes to the growth of needle-like crystals more than the rapid one. In a pure lactose solution no needle-shaped crystals were observed.

Key words:

, , ,




793-800 A. Põldvere, L. Lepasalu, A. Tänavots, J. Olt, U. Sannik, A. Sats,R. Saar, R. Martinson and V. Poikalainen,
An alternative method for meat shear energy estimation during ageing
Abstract |
Full text PDF (582 kB)

An alternative method for meat shear energy estimation during ageing

A. Põldvere¹, L. Lepasalu¹, A. Tänavots¹, J. Olt¹, U. Sannik¹⋅², A. Sats¹,R. Saar¹, R. Martinson³ and V. Poikalainen¹,*

¹Estonian University of Life Sciences, Kreutzwaldi 1, EE51014 Tartu, Estonia; *Correspondence: vaino.poikalainen@emu.ee 2Competence Center of Food and Fermentation Technologies, Akadeemia tee 15, EE12618 Tallinn, Estonia 3AS Rakvere Meat Processing Plant, Roodevälja, Sõmeru, EE44207 Lääne-Viru County, Estonia

Abstract:

The aim of this research was to study an alternative method (gravitational impulse method) for meat shear energy estimation. A falling shear blade (guillotine) with constant potential energy was used. Shear energy was determined as the difference between the initial potential energy of the blade and the residual energy measured via the impulse provided by the shear blade during collision with the force plate on the bottom of the device. The shear energy measured by the gravitational impulse method was compared to the data received by the texture analyser TMS PRO based on the Warner-Bratzler method. The meat shear parameters of de-boned beef striploin samples were measured after 2, 7, 14, 21, 28 and 35 days of ageing at 0–2°C. The results of both methods (gravitational impulse method and Warner-Bratzler method) indicated similar trends of shear energy lessening during beef ageing. Based on the preliminary results, it can be concluded that the gravitational impulse method is suitable for evaluation of meat texture during ageing as well. The main advantage of this method is its simplicity and the low price of the device.

Key words:

, , , ,




801-806 A. Sats, H. Mootse, S. Pajumägi, A. Pisponen, V. Tatar and V. Poikalainen
Estimation of Particle Size Distribution in Bovine Colostrum Whey by Dynamic Light Scattering (DLS) Method
Abstract |
Full text PDF (218 kB)

Estimation of Particle Size Distribution in Bovine Colostrum Whey by Dynamic Light Scattering (DLS) Method

A. Sats*, H. Mootse, S. Pajumägi, A. Pisponen, V. Tatar and V. Poikalainen

Estonian University of Life Sciences, Institute of Veterinary Medicine and Animal Sciences, Department of Food Science and Technology, Kreutzwaldi ⁵⁶/⁵, EE⁵¹0¹⁴ Tartu, Estonia; *Correspondence: andres.sats@emu.ee

Abstract:

Colostrum whey consist bioactive compounds in considerable concentration. For isolation of these compounds the particle size has crucial importance. The aim of this work was to study possibilities of using dynamic light scattering method – DLS (Malvern Zetasizer Nano ZS) for colostrum whey particle size distribution estimation. The first and second milking colostrum samples were skimmed by centrifugal separation and casein of these was enzymatically coagulated by rennet (chymosin). Obtained whey was diluted (¹:²00) by distilled water and filtered (cut-off 0.⁴⁵ m) to get probes for estimation of particle size. Particle size distribution in colostrum whey probes had maximally three peaks and polydispersity indices from 0.¹⁵⁷ to 0.⁵⁴¹. Prevailing peak of the distribution was found at size from ¹⁴⁴ to ²¹0 nm, which apparently corresponds to hydrodynamic diameter of immunoglobulin IgG¹.

Key words:

, , , ,




807-812 A. Sats, H. Mootse, L. Lepasalu and V. Poikalainen
Use of Delvotest T for Quantitative Estimation of β-lactam Antibiotic Residues in Waste Milk and for Evaluation of Thermal Treatment Efficiency – a Methodical Pilot Study
Abstract |
Full text PDF (211 kB)

Use of Delvotest T for Quantitative Estimation of β-lactam Antibiotic Residues in Waste Milk and for Evaluation of Thermal Treatment Efficiency – a Methodical Pilot Study

A. Sats*, H. Mootse, L. Lepasalu and V. Poikalainen

Estonian University of Life Sciences, Institute of Veterinary Medicine and Animal Sciences, Department of Food Sciences, Kreutzwaldi ⁵⁶/⁵, EE⁵¹0¹⁴ Tartu, Estonia; *Correspondence: andres.sats@emu.ee

Abstract:

The aim of this work was to study possibilities of using microbiological broad-spectrum inhibitor test (Delvotest T) for express estimation of antibiotic residues in bovine milk. For quantitative estimation the waste-milk samples were stepwise diluted (dilution array) by antibiotic-free milk until negative test result was achieved. Another objective was to evaluate heat treatment efficiency of waste-milk in order to degrade antibiotic residues in it. Heat treatment (in water bath) at ⁹0°C was chosen according to references in literature. In order to study certain drug residue the waste-milk samples were collected at the next milking after medical treatment. Two different drugs were investigated: Carepen and Norocillin. Preliminary results indicated that the average concentration of antibiotic residue (active substance of drugs) exceeded European MRL (Maximum Residue Limit) ⁴,¹00 (± ²,⁴0⁸) and ¹³.0 (± ⁵.⁷) times respectively. The average heat treatment duration at ⁹0°C (until negative test result of Delvotest T) was ¹⁵.0 (± ⁵.0) and ⁷.⁸ (± ¹.⁵) hours respectively.

Key words:

, , ,




813-820 E. Suchkova, B. Shershenkov and D. Baranenko
Effect of ultrasonic treatment on metabolic activity of Propionibacterium shermanii, cultivated in nutrient medium based on milk whey
Abstract |
Full text PDF (395 kB)

Effect of ultrasonic treatment on metabolic activity of Propionibacterium shermanii, cultivated in nutrient medium based on milk whey

E. Suchkova, B. Shershenkov* and D. Baranenko

Institute of Refrigeration and Biotechnologies, ITMO University, Lomonosova 9, Saint-Petersburg, Russia; *Correspondence: boris.shershenkov@list.ru

Abstract:

Utilization of milk whey still remains one of the most serious problems of the modern world dairy industry. Because of high biological value of whey it can be used as nutrient media in techniques of direct microbiological synthesis of complex high-molecular substances, for example the B12 vitamin, which participate in various biocatalytic reactions in organism providing normal functioning of the brain, nervous and hematogenic systems. The main industrial producer of B12 vitamin is Propionibacterium shermanii species, which can use lactose as main carbon source and can develop directly in milk whey. However, common ways of vitamin B12 microbiological production can’t be applied on the food plants and there must be used alternative safe methods, such as ultrasonic treatment of the cell culture, which can carry out the direct modulation of metabolic activity of bacteria for increasing of a yield of B12 vitamin. For the definition of ultrasonic processing influence on metabolism of Propionibacterium freudenreichii ssp. shermanii industrial strain it was cultivated in the nutrient media based on milk whey and treated by low intensity ultrasound at a frequency of 20 kHz within 10 and 20 min each 24 h. Received results allow to suggest that ultrasonic modulation of propionic bacteria metabolic activity can be used for an intensification of B12 vitamin biotechnological obtaining and manufacturing of fermented food products based on milk whey and enriched with B12 vitamin.

Key words:

, , , ,




821-824 R. Vokk, E. Tedersoo, T. Lõugas, K. Valgma and J. Rosend
Comparative study on anti-oxidant activity of garlic grown in different regions
Abstract |
Full text PDF (159 kB)

Comparative study on anti-oxidant activity of garlic grown in different regions

R. Vokk*, E. Tedersoo, T. Lõugas, K. Valgma and J. Rosend

Department of Food Processing, Tallinn University of Technology, Ehitajate tee ⁵, Tallinn, EE¹⁹0⁸⁶, Estonia; *Correspondence: raivo.vokk@ttu.ee

Abstract:

Currently reliance on natural products such as garlic and other vegetables is gaining popularity to combat various physiological threats including oxidative stress, cardiovascular complexities, cancer insurgence, and immune dysfunction. Garlic (Allium sativum L.) holds a unique position in history, belongs as a natural ingredient to different cuisines and was recognized for its therapeutic potential. Extensive research work has been carried out on the health promoting properties of garlic, often referred to its sulfur containing metabolites i.e. allicin and its derivatives. The aim of the present study was to compare garlic originated from different parts of the world (Chinese, Spanish, Lithuanian etc) on the basis of their anti-oxidant activity to evaluate their potential for different applications. As a result distinctive differences have been found in anti-oxidant activity of different garlic varieties. Garlic grown in Estonia possessed the highest antioxidant activity among the raw varieties. Black garlic has remarkable higher anti-oxidant content in comparison with other garlic samples.

Key words:

, ,




825-834 L. Zabodalova, T. Ishchenko, N. Skvortcova, D. Baranenko andV. Chernjavskij
Liposomal beta-carotene as a functional additive in dairy products
Abstract |
Full text PDF (307 kB)

Liposomal beta-carotene as a functional additive in dairy products

L. Zabodalova¹*, T. Ishchenko¹, N. Skvortcova¹, D. Baranenko¹ andV. Chernjavskij²

¹The Institute of Refrigeration and Biotechnologies, ITMO University, 191002 Lomonosova Street 9, Saint-Petersburg, Russia; *Correspondence: zabodalova@gmail.com 2Research Institute of Influenza, 197376, prof. Popova str., 15/17, Saint-Petersburg; Russia

Abstract:

Encapsulation is of growing use in food technologies for various bioactive compounds. The study addresses the aspect of possible improved physiological activity that encapsulated form can enable. Liposomes obtained by dehydration/rehydration method were used as carriers of beta carotene. The liposomal additive was used for fortification of low-fat milk drink. Formation, structure and stability of the liposomes were controlled in the product matrix by transmission electron microscopy. Fraction-dispersed composition and aggregate stability of liposomal particles were investigated by means of dynamic light scattering. Liposomal beta-carotene was found to maintain stability during storage at 4 ± 2ºС within 15 days. Hexobarbital sleeping time test performed on mice fed with the product showed enhanced hepatostimulation effect achieved by the liposomal additive compared to free beta carotene. Liposomal beta-carotene is suggested to be used for development of functional health-promoting dairy products. Key words: liposomes, beta-carotene, bioactive compounds, encapsulation, hepatostimulation activity.

Key words:




837-842 P. Kic, and L. Růžek
The microbiological environment in specific rooms of a university campus
Abstract |
Full text PDF (165 kB)

The microbiological environment in specific rooms of a university campus

P. Kic¹,* and L. Růžek²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Kamycka 129, 16521, Prague 6, Czech Republic; *Correspondence: kic@tf.czu.cz 2Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Kamycka 129, 165 21 Prague 6, Czech Republic

Abstract:

The aim of this paper is to present the results of a microclimatic research focused on the microbiological contamination in different rooms of the campus of the Czech University of Life Sciences Prague with emphasis on bacteria and filamentous fungi, including presence of the allergenic genus Cladosporium. Attention is paid to the purpose of the rooms, ventilation or air-conditioning, and also to problems with the technological equipment installed and used in the rooms. In the frame of this research, were examined the indoor conditions in lecture rooms, the special breeding sections for laying hens and several parts of an experimental brewery. Different intensities of ventilation and air-conditioning influenced the quality of the indoor environment in the studied rooms during the year. Key word: indoor air quality, bacteria, filamentous fungi, temperature, air humidity.INTRODUCTION

Key words:




843-850 H. Kalkis,, Z. Roja and V. Kalkis
Physical load analysis in hotel cleaning work
Abstract |
Full text PDF (236 kB)

Physical load analysis in hotel cleaning work

H. Kalkis¹⋅²,*, Z. Roja³ and V. Kalkis³

¹Institute for Occupational Safety and Environmental Health, Riga Stradins University, 16 Dzirciema Street, Riga, LV-1007, Latvia; *Correspondence: henrijs.kalkis@rsu.lv 2Faculty of Economics and Management, University of Latvia, Aspazijas blvd. 5LV-1050, Riga, Latvia 3Ergonomics research Centre, University of Latvia, K. Valdemara 48, LV-1013 Riga, Latvia

Abstract:

Hotel cleaning work is one of the physically demanding professions. Employees in hotel cleaning processes are subjected to compulsory work postures, frequent body, arm, and leg movements, awkward turns due to areas of restricted spaces or inappropriate work equipment. Such workload can result in health problems and deteriorate health. Therefore, the aim of the research was to determine the physical load for hotel office cleaning staff. 23 hotel cleaners, all female, participated in the investigation participated. For the physical load analysis, a questionnaire, the Key Indicator Method, the quick exposure check method, and heart rate monitoring were chosen. It was proved in this research that the work of hotel office cleaners corresponds to the category of light and moderate workload despite the fact that hotel office cleaners themselves consider the work process to be very intensive and physically demanding. Further studies are necessary in order to clarify the fatigue level and other social risks that can influence the physical workload of employees.

Key words:

, , ,




851-862 S.N. Kalnins, J. Gusca, S. Valtere, R. Vanaga and D. Blumberga
Transition to low carbon society. Evaluation methodology
Abstract |
Full text PDF (308 kB)

Transition to low carbon society. Evaluation methodology

S.N. Kalnins, J. Gusca, S. Valtere, R. Vanaga and D. Blumberga*

Institute of Energy Systems and Environment of the Riga Technical University, Kronvalda bulvaris ¹, LV-¹0¹0, Riga, Latvia; *Correspondence: dagnija.blumberga@rtu.lv

Abstract:

The need to resolve environmental pollution and climate change issues stimulate the introduction of new legislation to further lead to technological progress in the sphere of renewable energy sources and green technology. Nonetheless, the impact of the fragmented though concrete results-oriented activities on human development and on the transition to a low carbon society is difficult to assess. The paper describes a combined methodology for evaluation of the combined efforts contributing to transition to a low carbon society. The methodology includes ¹¹ modules and encompasses the main drivers of sustainability and the thinking of a low carbon society– policy development (legislation), education and research, projects and programmes, and interest groups (stakeholders), which includes such groups as decision-makers, industries, educators NGOs and society as a whole. The results of the comprehensive evaluation provides points from which development activities can be launched in order to form a resilient, low carbon future. Key words: climate change, programmes, policy, education, stakeholders, capacity development.INTRODUCTION

Key words:




863-874 T. Koppel and P. Tint
Reducing exposure to extremely low frequency electromagnetic fields from portable computers
Abstract |
Full text PDF (421 kB)

Reducing exposure to extremely low frequency electromagnetic fields from portable computers

T. Koppel* and P. Tint

Tallinn University of technology, Ehitajate tee ⁵, EE¹⁹0⁸⁶ Tallinn, Estonia; *Correspondence: tarmo.koppel@ttu.ee

Abstract:

The relevance of this article can be described by the rapid development in computer technology which has resulted in widespread use of laptop computers. Consequently the population is now more exposed to the electromagnetic fields, emanating from such devices. The aim of this article is to test various intervention measures which would help to reduce the exposure. The authors focus only on the measures easily applicable by the general public. The effectiveness of the interventions is measured by reduced electric and magnetic field. This study focuses on the electromagnetic fields in the range of ⁵0 Hz to ⁴00 kHz. The importance of minimizing exposure to the electromagnetic fields is also stressed by the high level European bodies. Reduction of environmental risk factors, where possible, is in fact the corner stone of European occupational health legislation. The measurements are conducted using a novel ¹⁴-point model, covering the entire body of the user. Measurements from ⁴⁶ laptop computer workplaces provided data about ¹⁵⁶ unique exposure instances. The measurement results show that the least exposure scenario comprises of a laptop computer working on battery, having external input devices and display, the casing of the computer being properly grounded and power wires and adapters are positioned away from the user’s body.

Key words:

, , , ,




875-880 Ü. Kristjuhan
Ergonomics slow down ageing and postpone ageing related diseases
Abstract |
Full text PDF (185 kB)

Ergonomics slow down ageing and postpone ageing related diseases

Ü. Kristjuhan

Chair of Labour Environment and Safety, Tallinn University of Technology, Ehitajate tee 5, EE19086 Tallinn, Estonia; e-mail: ulo.kristjuhan@ttu.ee Abstract: For thousands of years, people have been interested in healthy ageing without diseases and in slowing down ageing. They are interested in longer-lasting youthful condition. Ageing is determined by physiology, biological ageing is accumulation of bodily changes that increase the possibility of death. There is no border line between ageing and age-related diseases, but a continuum from ageing to diseases. Longer health is good for a country’s economy: social expenses are lower and people will retire later. Scientists have studied possibilities of postponing ageing for decades, but they have not found good solutions. In recent years, some attention has been paid to ergonomics. There is reason to conclude that ergonomics activities can be effective in slowing the pace of ageing. Ergonomics uses very different methods (psychological, physiological, physical, mathematical, etc.) for finding solutions, uses various professional skills (engineering, physiology, health sciences, psychology, etc.), and applies systems approach. Psychological knowledge can help solve many complex prevention problems. Our ergonomic research carried out in 1965−2000 in industrial enterprises in Estonia, Russia, Finland, and other countries also confirms these theoretical considerations. These studies have shown that it is possible to prolong good ability to work and health by up to 20 years. Ergonomics research can have potential in postponing age-related diseases, elucidation of new risk factors to health, and prolonging ability to work. Key words: ergonomic research, ageing, health, ability to work, diseases, industrial enterprises, risk factors.

Abstract:

INTRODUCTION

Key words:

,




881-888 Ü. Kristjuhan
What is the priority in the problem of ageing?
Abstract |
Full text PDF (221 kB)

What is the priority in the problem of ageing?

Ü. Kristjuhan

Chair of Labour Environment and Safety, Tallinn University of Technology, Ehitajate tee 5, EE19086 Tallinn, Estonia; e-mail: ulo.kristjuhan@ttu.ee

Abstract:

What should we do to help solve the problem of postponing ageing? What is the priority? Let us define human ageing as accumulation of damage in the human organism that increases the probability of death. There are various problems of ageing: psychological ageing, biological ageing, etc. The central problem is biological ageing. If biological ageing is postponed, diminishing and postponing of diseases and increase in the older workers’ ability to work are possible. People can stay healthy longer and countries save on social expenses. The problem of biological ageing is complex due to many different subproblems and adhering problems. Research in biological ageing is relatively poorly funded. Its funding and research depend on gaining public attention to this research. Many scientists think that there are no solutions for postponing ageing. Factually, no problem will be solved if we proceed from the assumption that the problem is not solvable. Researchers need popular support for the concept that ageing is a solvable problem. Higher public interest in biological ageing research compared to the present is possible through research of the causes of the average life expectancies of big contingents (countries, big population groups) and also interventions based on the risk factors of all-cause mortality. Studies of different causes of mortality in various countries may point to new risk factors to health and ageing. Interventions according to the known risk factors to age-related diseases can postpone these diseases and ageing markedly, by 10–20 years, and also increase the public interest in research in biological ageing. Key words: biological ageing, biomedical gerontology, health, life expectancy, research priority, risk factors.

Key words:




889-894 V. Nídlová and J. Hart
The impact of light conditions on identifying facial features
Abstract |
Full text PDF (265 kB)

The impact of light conditions on identifying facial features

V. Nídlová* and J. Hart

Department of Technological Equipment of Buildings, Faculty of Engineering, Czech University of Life Sciences Prague, Kamýcká 129, 16521 Prague, Czech republic; *Correspondence: nidlova@tf.czu.cz

Abstract:

Biometry in the field of identifying people is a highly topical theme these days. The most widespread area is identification of a person on the basis of fingerprints, nevertheless scanners of the bloodstream, iris and retina in particular are undergoing development, as well as identification on the basis of facial features. In the case of scanners which distinguish people according to their face, user problems are appearing. One of these problems is the surrounding environment of the scanner device, in particular light conditions. According to tests, it is necessary to conduct identification of people under laboratory conditions, which is not acceptable from the user perspective. It is essential to consider this problem and to innovate and extend the system for identification on the basis of facial features. It is necessary for the system to react, if possible, with a minimal error rate and within the fastest response time. Through the help of testing light conditions, an improvement was achieved in the capability of identifying facial features, and at the same time a further modification was proposed to perfect the existing technology.

Key words:

, , , ,




895-906 K. Reinhold, S. Kalle and J. Paju
Exposure to high or low frequency noise at workplaces: differences between assessment, health complaints and implementation of adequate personal protective equipment
Abstract |
Full text PDF (822 kB)

Exposure to high or low frequency noise at workplaces: differences between assessment, health complaints and implementation of adequate personal protective equipment

K. Reinhold*, S. Kalle and J. Paju

Institute of Business Administration, Tallinn University of Technology, Ehitajate tee 5, EE12618 Tallinn, Estonia; *Correspondence: karin.reinhold@ttu.ee

Abstract:

Employees are exposed to high and low frequency noise which may cause different health effects. Hearing loss first occurs in the high frequency range, low frequency usually causes sleeping disturbances and annoyance. TES 1358 sound analyzer with 1/3 octave band was used to measure the equivalent sound pressure level, the peak sound pressure level, and the noise frequency spectrum at different workplaces. All the results were compared to Estonian and International legislations. High frequency noise was studied in metal, electronics and wood processing industries. The results showed that in several cases, the normative values were exceeded and the highest values appeared in the range of speech frequencies. Frequency analysis indicated that the noise level spectra at work stations of various machines differed in patterns. The low frequency spectra on a ship showed peaks in the frequency range of 50…1,250 Hz. Most employers provided workers with personal protective equipment against noise, but when selecting ear muffs, noise frequency had not been taken into consideration and therefore workers in the same enterprise used similar ear muffs. Knowledge of the prevailing frequencies assists to decide which ear protection should be used to avoid damage. An adequate hearing protector device can reduce the noise exposure significantly.

Key words:

, , ,




907-914 M. Reinvee, and K. Jansen
Utilisation of tactile sensors in ergonomic assessment of hand–handle interface: a review
Abstract |
Full text PDF (450 kB)

Utilisation of tactile sensors in ergonomic assessment of hand–handle interface: a review

M. Reinvee¹,* and K. Jansen²¹

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi ⁵⁶, EE⁵¹0¹⁴ Tartu, Estonia;
*Correspondence: mart.reinvee@emu.ee
²Institute of Exercise Biology and Physiotherapy, University of Tartu, Jakobi ⁵, EE⁵¹0¹⁴ Tartu, Estonia

Abstract:

Many ergonomic studies deal with comfort or try to find optimal parameters for tool design. Most of these studies also emphasise the importance of coupling between hand and handle. In order to collect objective data about hand–handle interface pressure, tactile sensors can be used. A trade-off between sensor dimensions, sensel density, robustness, and accuracy must be considered while choosing between commercial tactile sensors for ergonomic investigations. Based on literature from the last two decades, the main aspects of tactile sensors usage are highlighted.

Key words:

, ,




915-924 T. Sirge, J. Ereline, T. Kums, H. Gapeyeva and M. Pääsuke
Musculoskeletal symptoms, and perceived fatigue and work characteristics in supermarket cashiers
Abstract |
Full text PDF (291 kB)

Musculoskeletal symptoms, and perceived fatigue and work characteristics in supermarket cashiers

T. Sirge*, J. Ereline, T. Kums, H. Gapeyeva and M. Pääsuke

Institute of Exercise Biology and Physiotherapy, University of Tartu, Jakobi 5, EE51014 Tartu, Estonia; *Correspondence: triinu.sirge@ut.ee

Abstract:

Working in the sitting position is often regarded as a cause for discomfort and pain in the musculoskeletal system. The aim of the present study was to evaluate musculoskeletal symptoms in different body regions in association with the perceived fatigue and work characteristics in supermarket cashiers, who are predominantly working in the sitting position. The subjects were 67 female supermarket cashiers with the mean (± SD) age of 33.5 years, body mass index (BMI) of 23.8 ± 0.4 kg m-2 and the working time of 9.7 hours a day. All subjects completed the standardized Nordic Questionnaire and self-administered questionnaire concerning cashier’s work, bio-demographic variables and fatigue. The results of this study indicated that 86.6% of subjects reported experiencing discomfort at least in one body area. Musculoskeletal symptoms in the last 6 months were localized primarily in the lower back and neck regions (67.2% and 53.7%, respectively) and in the last 7 days also in the lower back (44.8%) and equally in the neck and wrist (40.3%). Correlation analysis showed that low back pain (LBP) perceived during the last 7 days was associated with knee pain (r = 0.44, p < 0.001). Last 6 months LBP was associated with shoulder (r = 0.35, p < 0.01) and neck pain (r = 0.43, p < 0.001) during last 6 months. On the other hand, no significant correlation emerged between LBP, fatigue and work characteristics (physical and mental fatigue after workday, rushing and monotony at work). From the cashiers, 80.9% had experienced rushing at work, while the majority of them (89.6%) felt physical fatigue after the workday, and 62.7% reported their work being monotonous. Approximately one-half of the subjects (49.3%) practiced recreational sport in their free time. It was concluded that in supermarket cashiers the highest prevalence rate of discomfort and pain was emerged in low back and neck, and they perceived rushing and monotony at work and physical and mental fatigue after the workday. Recreational sport can be recommended as a preventive activity for avoiding discomfort.

Key words:

, , , ,




925-934 A. Traumann, M. Kritsevskaja, P. Tint, and D. Klauson
Air quality as an important indicator for ergonomic offices and school premises
Abstract |
Full text PDF (413 kB)

Air quality as an important indicator for ergonomic offices and school premises

A. Traumann¹, M. Kritsevskaja², P. Tint¹,* and D. Klauson²

¹Department of Work Environment and Safety, Tallinn University of Technology, Ehitajate 5, EE19086 Tallinn, Estonia; *Correspondence: piia.tint@ttu.ee 2Department of Chemical Engineering of Tallinn University of Technology, Ehitajate 5, 19086 Tallinn, Estonia

Abstract:

The health risk assessment model for office rooms contains the physical indoor air factors and the risks connected with the use of computers. Four comfort classes have been postulated. Indoor air quality is the main risk factor at workplaces such as office rooms and schools besides non-ergonomic use of computers. High levels of carbon dioxide (CO2) could be observed due to poor ventilation systems and inadequate air exchange due to inoperable windows. Overcrowded classrooms could also be the reason for a high CO2 level. Lowering the occupancy and increasing the breaks between classes could alleviate the high CO2 concentrations in schools and offices. The data of Estonian investigators are analyzed. Experiments for determination of the adequacy of ventilation rate and the respective build-up of CO2 are carried out by the authors of the paper.

Key words:

, , , ,




937-948 V. Bulgakov, S. Pilipaka, V. Adamchuk and J. Olt
Theory of motion of a material point along a plane curve with a constant pressure and velocity
Abstract |
Full text PDF (453 kB)

Theory of motion of a material point along a plane curve with a constant pressure and velocity

V. Bulgakov¹*, S. Pilipaka¹, V. Adamchuk² and J. Olt³

¹National University of Bioresources and Nature Management of Ukraine, 15 Heroiv Oborony St., 03041 Kyiv, Ukraine;
*Correspondence: vbulgakov@meta.ua
²National Scientific Centre ‘Institute for Agricultural Engineering and Electrification’ National Academy of Agrarian Sciences of Ukraine (NAASU), 11 Vokzalna St., Glevakha-1, Vasylkiv District, Kyiv Region, 08630, Ukraine
³Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56, 51014 Tartu, Estonia; jyri.olt@emu.ee

Abstract:

The theory of motion of a material point has been developed, as a result of which plane curves as orthogonal sections of cylindrical surfaces with horizontal generators that provide a constant force of pressure during motion of a particle along a curve at a constant velocity have been found. New differential equations of motion of a material point along a plane trajectory on the surface of the cylinder have been made. Visualisation of the obtained results has been performed. Individual cases of motion where the force of pressure on the surface was bigger, smaller or equal to the weight of the particles, and where reaction of the surface equalled zero have been found. The given theory can be successfully used for design of mouldboard surfaces of cultivator machines.

Key words:

, , , , ,




949-954 J. Hart, V. Nídlová and M. Přikryl
Reliability of detection of sources of infrared radiation in security alarm and distress signal systems
Abstract |
Full text PDF (234 kB)

Reliability of detection of sources of infrared radiation in security alarm and distress signal systems

J. Hart*, V. Nídlová and M. Přikryl

¹Department of Technological Equipment of Buildings, Faculty of Engineering, Czech University of Life Sciences Prague (CULS), Kamýcká 129, 16521 Prague, Czech republic; *Correspondence: jhart@tf.czu.cz

Abstract:

The problem of detecting sources of infrared radiation affects a large proportion of security alarm and distress signal systems. In a time of increasing property crime, it is highly important for passive infrared detectors (PIR) to be able to detect motion within the guarded area reliably and free of error. In the case of installation of passive infrared detectors (PIR) it is naturally important not only to ensure correct installation, to gauge the external influences impacting upon the detector and ensure proper maintenance, but also to guarantee their capability of detection under more arduous conditions. The tests which have been conducted examine both the normal operation of the PIR detectors and the operation of these detectors under extreme conditions (temperature, soiling, screens etc.). These tests are important both from an informative perspective and due to the possibilities of development of potential counter-measures which could lead to their improvement and an enhancement of their level of security.

Key words:




955-966 V. Osadcuks, A. Pecka, A. Lojans and A. Kakitis
Experimental research of proximity sensors for application in mobile robotics in greenhouse environment
Abstract |
Full text PDF (396 kB)

Experimental research of proximity sensors for application in mobile robotics in greenhouse environment

V. Osadcuks*, A. Pecka, A. Lojans and A. Kakitis

Faculty of Engineering, Latvia Universty of Agriulture, ⁵ J.Cakstes blvd., LV-³00¹ Jelgava, Latvia; *Correspondence: vtl@tvnet.lv

Abstract:

Mobile robots for greenhouse automation are not yet used commercially, but scientific research are being performed in various aspects of using robots in greenhouses. For now, plant examination for diseases and insects, spraying and watering tasks are mostly considered. In all cases, a robot should be able to orient itself globally in the environment and locally relative to the working objects e.g. plants, obstacles and other robots if a multi robot system is assumed. In greenhouses, proximity sensors are used for simple object detection and distance measurement with both metallic and non-metallic materials as well as plants. Consequently, capacitive, ultrasound and optical type sensors can be used. It is known that they are affected by varying temperature, humidity and moisture conditions. In this research, we have used a specialized microclimate chamber to perform experiments in a modeled greenhouse environment with controlled temperature, relative humidity. The controlled environmental parameters were combined to represent real world greenhouse conditions. Three types of materials were used for detection (WxHxD): ¹ mm steel plate ²⁵⁵ x ³⁸0 mm, ¹ mm ABS ²⁴⁵ x ³³0 mm plastic plate, and ¹¹⁸ x ¹⁸0 x ⁶0 mm plastic container with water. The environment and the type of the detectable object were used as independent variables. The examined parameters, i.e. the dependent variables of the digital type sensors, were the maximum and minimum detection limits and hysteresis. A statistical analysis was performed to find the factors which may affect the reliability of proximity sensors measurements in greenhouse environment.

Key words:

, , ,




967-976 L. Laivina, J. Pubule and M. Rosa
A multi-factor approach to evaluate environmental impact statements
Abstract |
Full text PDF (258 kB)

A multi-factor approach to evaluate environmental impact statements

L. Laivina, J. Pubule* and M. Rosa

Riga Technical University, Institute of Energy Systems and Environment, Kronvalda boulv. ¹, LV-¹0¹0 Riga, Latvia; *Cerrespondence: jelena.pubule@rtu.lv

Abstract:

The goal of this study is to develop a method for assessing Environmental Impact Statement (EIS) according to various criteria, and to develop recommendations to improve statements and the EIA procedure. To develop a method to assess report quality, the most significant current methods were examined. Their advantages and disadvantages were analyzed and, as a result, the most appropriate method structure was defined – a control list with quality criteria. To determine the quality criteria of an EIA, the effective basic principles of the EIA were formulated based on sources in the literature. During the study, the three most significant elements of a quality EIA were defined. These have been incorporated into the method developed in this project as the most significant criteria. As a result, a systematic method to assess an individual EIS was developed. The method includes quality criteria, which have been determined to be the most significant as a result of an analysis of the efficiency of the EIA procedure. The method has been adapted to the planned amendments in the EIA directive, incorporating these criteria. The structure of the method adheres to another fundamental goal of the directive’s amendments – to decrease the administrative load of the EIA procedure. It is anticipated that with the aid of this method, by assessing only the most important report elements in depth, that the time necessary for a competent institution to evaluate a report will be reduced. Key words: environmental impact assessment, sustainability, evaluation methodology, environmental impact statement.QUALITY OF THE EIS

Key words:

, ,




979-988 A. Beloborodko, M. Rosa, F. Romagnoli and D. Blumberga
Overview of the waste-to-energy sector in Latvia: driving forces for a cluster creation
Abstract |
Full text PDF (195 kB)

Overview of the waste-to-energy sector in Latvia: driving forces for a cluster creation

A. Beloborodko*, M. Rosa, F. Romagnoli and D. Blumberga

Riga Technical University, Institute of Environment and Energy Systems, Kronvalda blvd. 1, LV-1010 Riga, Latvia; *Correspondence: anna.beloborodko@rtu.lv

Abstract:

Waste to energy (WTE) sector includes collecting and pre-treatment of various types of organic and recyclable waste that is used as feedstock for conversion technologies generating valuable outputs (i.e. power, heat, biomethane, syngas etc.). Consequentially, the WTE value chain includes stakeholders from waste management and energy production markets. The development of Latvian WTE is governed by advancements and availability of technology and innovation, the national legislation and binding regulations, and cooperation between the involved stakeholders. To promote more efficient waste management techniques, increase the use of alternative energy sources and improve cooperation between different target groups within the WTE sector (i.e. policy makers, investors and researchers) the establishment of a WTE cluster in Latvia is proposed. The initial information about the state-of-the-art of the WTE sector in Latvia is vital for development of such cluster. The aim of this paper is to characterize the WTE sector in Latvia and analyse its driving forces (technology push versus demand pull) in order to determine a strategy for WTE cluster development. To reach this objective an analytical framework based on the technology push and demand pull methodological approach is applied. To reach the aim of this study, an inventory of WTE related stakeholders in Latvia is developed and the push and pull factors driving the development of WTE field are defined. Various factors and their interactions are analysed to determine which are the most influential for Latvian WTE sector development, finally we provide our conclusions and discussion.

Key words:

, , ,




989-998 M. Kiviste and R. Lindberg
The feasibility of phase change materials in building structures for saving heating energy in the Nordic climate
Abstract |
Full text PDF (459 kB)

The feasibility of phase change materials in building structures for saving heating energy in the Nordic climate

M. Kiviste* and R. Lindberg

DepartmentofCivilEngineering,TampereUniversityofTechnology,Tekniikankatu 12, P.O.Box 600,FI-33101 Tampere, Finland; *Correspondence: mihkel.kiviste@tut.fi

Abstract:

The study is based on a nearly two-decade research at the Department of Civil Engineering at the Tampere University of Technology (Finland). The purpose of the current study is to find out the structural solutions for the thermal storage of solar radiation in buildings. A significant effect of solar gains was noticed in massive external walls as well as roof structures in sunny days from March until September. However, modern lightweight materials lack the thermal inertia to store energy. An idea to utilize the latent heat of phase change materials (PCMs) inside the insulation of a light-weight roof structure enables to overcome this problem. The idea is supported with a principal example of the diurnal performance of a metal sheet roof structure as well as comparative calculation of the energies consumed and gained. The results of the current study show that PCMs have potential in the future application of light-weight roof structures. In general, efficient solar solutions still need to be developed in order to store energy in summer and to release it in winter.

Key words:

, , ,




999-1006 M. Repele, A.Paturska, K. Valters and G. Bazbauers
Life cycle assessment of bio-methane supply system based on natural gas infrastructure
Abstract |
Full text PDF (285 kB)

Life cycle assessment of bio-methane supply system based on natural gas infrastructure

M. Repele*, A.Paturska, K. Valters and G. Bazbauers

Institute of Energy Systems and Environment, Riga Technical University, Kronvalda Boulevard 1, Riga, LV1010, Latvia; *Correspondence: mara.repele@rtu.lv

Abstract:

Many sites for biogas production in Latvia currently do not have sufficient heat load to provide power production in co-generation mode. The alternative to relatively inefficient power production could be production of bio-methane which is known as one of the most important renewable option for gas supplies. After removal of contaminants bio-methane is of quality of natural gas and can be delivered to power plants and industry using the natural gas supply infrastructure. For analysis of environmental benefit of using bio-methane the environmental impact of the proposed solution has to be assessed. The aim of the study is to make life cycle assessment of the system for bio-methane supply to industrial plant via the natural gas grid. The analysed system includes bio-methane production and transport to the natural gas pipeline including the infrastructure. Functional unit was 1 MWh of bio-methane energy injected into the natural gas transmission pipeline. Life-cycle model was created and analysed with software ‘SimaPro’. ReCiPe and Eco-Indicator’99 were used as characterization methods to analyse the life-cycle environmental impacts. Results show the influence and contribution level expressed in mid-point categories as well as in a single-score indicator. The largest impact is created by use of fossil energy sources in production of bio-methane. The results can be used to design renewable energy supply systems and for the comparison of alternatives.

Key words:

, , ,