Tag Archives: storage

1405-1416 Z. Kruma, R. Galoburda, L. Tomsone, I. Gramatina, S. Senhofa, E. Straumite, D. Klava, T. Kince, I. Cinkmanis, J. Zagorska and D. Kunkulberga
Changes in the nutritional value of breakfast cereals containing germinated spring grain flakes during storage
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Changes in the nutritional value of breakfast cereals containing germinated spring grain flakes during storage

Z. Kruma*, R. Galoburda, L. Tomsone, I. Gramatina, S. Senhofa, E. Straumite, D. Klava, T. Kince, I. Cinkmanis, J. Zagorska and D. Kunkulberga

Latvia University of Life Sciences and Technologies, Faculty of Food Technology, Department of Food Technology, Rigas iela 22, LV-3004 Jelgava, Latvia
*Correspondence: zanda.kruma@llu.lv

Abstract:

The aim of current research was to assess the nutritional value of breakfast cereals containing germinated spring grain flakes and its changes after 6 month storage. Three types of breakfast cereals were prepared and packaged in two types of Standup pouches – Pap50g/Alu7/Pe60 (AL), Pap40g/PELD20/PE40 (PE). For the accelerated shelf life test the samples were stored at 35 ± 2 °C and dietary fibre, protein, fat, B-group vitamins, sugars, total phenol content and DPPH, ABTS+ radical scavenging activity were determined. Developed breakfast cereals have high nutritional value and all are high in fibre and thiamine. Additionally, sample S2 is source of protein, riboflavin, niacin, and S3 – is source of riboflavin and high in niacin. Comparing total phenolic content and antioxidant capacity of tested samples S3 showed the highest values. Storage and selected packaging influenced stability of nutrients, and for S1 and S2 AL showed better results whereas for S3 – PE.

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1509-1516 J. Táborský, A. Hejtmánková, E. Hlavatá and L. Chládek
A study of dynamics of bitter acids and xanthohumol in hop pellets during storage
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A study of dynamics of bitter acids and xanthohumol in hop pellets during storage

J. Táborský¹*, A. Hejtmánková¹, E. Hlavatá¹ and L. Chládek²

¹Czech University of Life Sciences, Faculty of Agrobiology, Food and Natural Resources, Department of Chemistry, Kamýcká 129, CZ165 00 Prague 6, Czech Republic
²Czech University of Life Sciences, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 00 Prague 6, Czech Republic
*Correspondence: taborsky@af.czu.cz

Abstract:

Eight varieties of hop pellets were analyzed for the contents of α-acids, ß-acids and xanthohumol according to the EBC 7.7 analytical method. The pellets were extracted with acidified mixture methanol – diethylether and analyzed using HPLC with a diode-array detector and a Nova-Pak column C18. Four series of analyses were performed: immediately after the unpacking of the pellets and then after five, seven and nine months of storage at 4 °C. According to the first series of analyses, the contents were assayed as following (α-acids, ß-acids, xanthohumol resp., all in weight % in pellets): Galaxy (13.4, 8.0, 0.74), Citra (11.1, 3.0, 0.48), Tradition (8.2, 8.0, 0.58), Cascade (4.5, 5.2, 0.25), Northern Brewer (4.0, 2.9, 0.37), Sládek (3.5, 4.0, 0.48), Saaz (2.0, 3.4, 0.24), and Triskel (1.7, 3.6, 0.18). According to these results, variety Galaxy was found as the richest in all three parameters. After nine months of storage at 4 °C, the weight loss of α-acids ranged from 4.1% (Citra and Triskel) to 66.4% (Galaxy). The losses of β-acids and xanthohumol were less distinctive (from zero to 31.3% and 25.7%, resp.) and indicated good long storage possibilities of these compounds at convenient conditions (darkness, low temperature, elimination of direct influence of oxygen).

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1375–1385 N. Naumenko, A. Paymulina, A. Ruskina, V. Khudyakov
The Effects of Various Raw Ingredients on Bread Quality
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The Effects of Various Raw Ingredients on Bread Quality

N. Naumenko,* A. Paymulina, A. Ruskina, V. Khudyakov

South Ural State University, Higher School of Medicine and Biology, Department of
Food and Biotechnology, 85 Lenina Avenue, 454080 Chelyabinsk, Russia;
*Correspondence: naumenko_natalya@mail.ru

Abstract:

The purpose of the current research is to study the mechanisms behind how various
raw ingredients affect the quality of bread. The objects of the research were the flour used in
making the bread (consisting of gluten at 28.5%, and with an ash content of 0.55), with no added
fats; tap water or activated water (treated in a USTA-0.4/22 OM ultrasonic processor (Volna,
Russia), operating at a frequency of 22±1.65kHz and at 30% of maximum output power (400W)
for mixing dough); and plant extract additives based on stevioside and fucoidan (fully replacing
the sugar). Included in the analysis were the effects of using activated water and combined plant
extract additives on organoleptic qualities (appearance, crust colour, crumb condition, taste,
stickiness during mastication, and friability), as well as the physical and chemical qualities
(moisture content, porosity, and acidity). Yeast activity was studied in dough which had been
produced using activated water and combined plant extract additives. An Altami-136T optical
microscope (Altami, Russia) was used to study the activity of yeast cells. The effects of activated
water and combined plant extract additives were analysed by examining the microstructure.
Microscopic studies were carried out using a Jeol JEM-2100 electron microscope (Jeol Ltd,
Japan). The results confirm that activated water and combined plant extract additives may be used
to improve the quality of fresh bread.

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1386–1398 L. Nilova, N. Naumenko, I. Kalinina
A Study of the Forms of Bound Water in Bread and Bakery Products using Differential Thermal Analysis
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A Study of the Forms of Bound Water in Bread and Bakery Products using Differential Thermal Analysis

L. Nilova¹, N. Naumenko²*, I. Kalinina²

¹Peter the Great St. Petersburg Polytechnic University, Institute of Industrial Management, Economics and Trade, Graduate School of Commodity and Service, Novorossiyskaya Street 50, 194021, Saint-Petersburg, Russia;
²South Ural State University, Higher School of Medicine and Biology, Department of Food and Biotechnology, 85 Lenina Avenue, 454080, Chelyabinsk, Russia;
* Correspondence: naumenko_natalya@mail.ru

Abstract:

The objective is to study the forms of bound water in bread and bakery products using differential thermal analysis, changes to these forms corresponding to different recipe components, and changes occurring during storage. The subject of this research are bread and bakery products made of wheat flour (with gluten content of 28.5%, and ash content of 0.55%): without added fat; with tap water or activated water used for dough mixing; with varying fat content (4 and 14%); protein-enriched with cedar nut flour (5%); and dietary (food) fiberenriched with red-fruited mountain ash and sea buckthorn powder (5%). The reference samples of bread and bakery products were stored in plastic film bags at 20 ± 2 °C for a period of 72 hours. The freshness was monitored by changes in the physical-chemical parameters (moisture content, swelling capacity, friability). The various forms of bound water were determined using the method of differential thermal analysis on a simultaneous TGA-DTA/DSC thermogravimetric analyzer, with a programmable temperature regime. Based on the obtained digital data on thermogram (TG) change, using Pearson’s criterion, a mathematical model has been created to identify the linear sections with a different inclination angle which are characterized by a constant rate of water removal. For all studied samples of bakery products, 6 linear sections were identified, but statistically significant results were obtained for sections III, IV and V, with the exception of section III for bakery products with cedar flour. Use of activated water, fat, and additives of cedar flour, powders of red-fruited mountain ash and seabuckthorn in the production of bread and bakery products leads to redistribution of water forms, which is confirmed by changes in the boundaries of the linear sections, both for freshly made products and for products after storage. As a result, these products stay fresh longer.

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892-899 D. Arslan
Effects of degradation preventive agents on storage stability of anthocyanins in sour cherry concentrate
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Effects of degradation preventive agents on storage stability of anthocyanins in sour cherry concentrate

D. Arslan

Division of Food Sciences, Department of Food Engineering, Faculty of Engineering and Architecture, Necmettin Erbakan University, Konya, Turkey e-mail: dears@konya.edu.tr

Abstract:

In this study the effects of sugar (sucrose, 25%), gallic acid (700 mg kg-1) and ascorbic acid (700 mg kg-1) were used in sour cherry concentrate in order to prevent the degradation of main anthocyanin compounds (cyanidin-3-glucosylrutinoside (Cy-3GR), cyanidin-3-rutinoside (Cy-3R) and cyanidin-3-glucoside (Cy-3G)) which are natural bioactive pigments responsible for red, blue and purple color of many fruits and vegetables. Thermal degradation of anthocyanins was evaluated by determination of anthocyanin content and calculation of the reaction rate constant, half-life of degradation, activation energy. Anthocyanin content decreased at all of the storage temperatures, as an example; there were 75, 51 and 55% reductions in Cy-3G contents of control samples (with no preventive agent) stored at 45, 24 and 4°C, respectively. The values of half-life time were above 200 days in most cases at all storage temperatures for sugar treated samples. Cy-3-GR (activation energy values 35.6-84.4 kJ mol-1) was found to be the most unstable among the other anthocyanins. The most contributing agent on anthocyanin stability was sugar, whereas ascorbic acid exhibited the lowest effect in terms of preventing anthocyanin degradation.

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1002-1009 T. Michlová,, H. Dragounová and A. Hejtmánková
Stability of vitamin A and E in powdered cow’s milk in relation to different storage methods
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Stability of vitamin A and E in powdered cow’s milk in relation to different storage methods

T. Michlová¹,*, H. Dragounová² and A. Hejtmánková¹

¹Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Chemistry, Kamýcká 129, 165 21, Prague, Czech Republic 2Dairy Research Institute Ltd, Ke dvoru 791/12A, 160 00, Prague, Czech Republic *Correspondence: michlova@af.czu.cz

Abstract:

In this article, the influence of different ways of storage on the content of vitamin A and E in powdered cow´s milk was studied. The cow´s whole milk powder was taken directly from the manufacturer and stored for one year in 4 different ways – in the light at room temperature, in the dark at room temperature, in a refrigerator at 8°C and in a freezer at -20°C. The content of vitamins was measured 4 times during the first month and then once a month. The samples were stored for one year. Vitamins A and E were determined by HPLC using DAD and FLD detectors. Vitamin A was identified in all samples but only α-tocopherol (out of various forms of vitamin E) was detected in all samples. In all cases steeper decline of both vitamins in first 14 days of storage was identified. The highest losses of vitamin A and E in powdered milk occurred during storage in the light at room temperature. The value decreased by 91 resp. 95% of the original value.

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197-204 L. Vent and A. Rybka
Storage technologies of picked hops during harvest
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Storage technologies of picked hops during harvest

L. Vent* and A. Rybka

Czech University of Life Sciences Prague, Faculty of Engineering, Kamýcká 129, Praha 6 – Suchdol, Postcode 16521, Czech Republic; *Correspondence: lvent@tf.czu.cz

Abstract:

To prevent interrupting the process of drying or picking due to lack or surplus of hops coming out of picking line, in most cases there is placed a storage container as a capacity equipment. In a container, however, hops are layered, thus temperature and relative humidity increase owing to an increased intensity of hop cones breathing and an insufficient airing, i.e. they mowburn. In the process of breathing a cone loses important substances which results in its worse quality and correspondingly in worse quality of the final product. This work builds on research from 2011. There were monitored changes of physical characteristic of picked hops during storage in container and compared with control variant. This aim of this work is to compare different storage technologies of picked hop in the container. There was a three variants. The control variant was a common stack with a perforated bottom. The second variant was a stack with active ventilation by electric fan. The third variant was a covered stack with passive air circulation. Al stacks had one cubic volume. Data of temperature and relative humidity were continually recorded by MINIKIN TH measuring equipment by EMS Brno company. Another analogue sensors to measure relative humidity and temperature were independently installed for check. The monitoring was each time carried out for 24 hours. Next there were collected a samples for laboratory analysis for product quality. During storage both the temperature and relative humidity of the control variant increased substantially, with temperature values reaching up to 41°C and relative humidity values 100%. The progress of temperatures was almost identical with all the measurements, that is why we present only the average values. The relative humidity of active ventilated variant increased up to 100% but temperature only up to 15°C. The values of humidity of passive ventilated variant were the same (100%) but values of temperature were lower instead of control variant. The highest measured temperature was about 22°C. The conclusion we may draw here says that the best way is passive air circulation. The lowest temperature was measured at variant with fan and it is most important for storage quality of hops but this variant is more expensive due to electric power.

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117-124 L. Vent and A. Rybka
Influence of humidity on the quality of baled hops at grower
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Influence of humidity on the quality of baled hops at grower

L. Vent* and A. Rybka

Czech University of Life Sciences Prague, Faculty of Engineering,Kamýcká 129, Praha 6 – Suchdol, Postcode 16521, Czech Republic;
*Correspondence: lvent@tf.czu.cz

Abstract:

Nowadays, in most of cases cured hops are pressed into square bales instead of roundbales. The specific weight of packaged hop is about 22% higher in the square bale and intensityof moistening of packaged hop is very important in this case. There is an increased risk ofdampening of hops in the square bale when the moistening intensity is too high. In the oppositecase is increased risk of destruction of hop cones due to low moistening intensity. The aim ofthis work was find out the influence of the intensity of moistening of hops before pressing intothe square bales on the development of humidity and quality of hops after pressing duringstorage at the grower. There were pressed square bales with humidity of hops from 9.2% to16.2%. The square bales with hop’s humidity 9–10% represented a dry variant, square baleswith hop’s humidity 11–12% represented an normal variant and square bales with hop’shumidity 13% and higher represented a wet variant. The square bales were stored on the firstfloor of the drying machine house at the grower. The range of storage temperature was from 7to 40 °C. All square bales were of the same condition. Humidity of the hops was monitoredduring 10 days. At the end of the measurement, there was carried out a laboratory analysis ofhops of all square bales. Samples were analysed for content of α – bitter acid and destruction ofhop cones. During storage, the humidity of wet variant dropped from 14.2 to 12.7% and thehumidity of dry variant increased from 9.37 to 11.1%. The destruction of hop cones was highestat dry variant (28%). On the contrary the lowest value was at normal variant (12.3%) and it isabout 43% less. However, the dependence of destruction of hop cones by humidity at asignificant level α = 0.05 has not been proven. There was no proven differences of content ofα – bitter acid between all three variants. The highest value 4.9% was at wet variant. We foundout a direct dependence of content of α – bitter acid on the humidity of hops in this case. Theresults of content of α – bitter and destruction of hop cones show that the best one was normalvariant with starting humidity from 11.2 to 11.6%.

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125-130 L. Vent and A. Rybka
Physical characteristics of picked hops during storage
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Physical characteristics of picked hops during storage

L. Vent* and A. Rybka

Czech University of Life Sciences Prague, Faculty of Engineering,Kamýcká 129, Praha 6 – Suchdol, Postcode 16521, Czech Republic;
*Correspondence: lvent@tf.czu.cz

Abstract:

To prevent interrupting the process of drying or picking due to lack or surplus ofhops coming out of the picking line, hops, in most cases are placed in a storage container.. In acontainer, however, hops are layered, thus temperature and humidity increase owing to anincreased intensity of hop cones breathing and an insufficient airing, i.e. they mowburn. In theprocess of breathing a cone loses important substances which results in its deteriorated qualityand correspondingly in the poor quality of the final product. Our task was to observe the courseof hop temperature and humidity in a storage container and to compare it with the checkvariant, which was loosely spread hops outside the container. Data of temperature and humiditywere continually recorded by COMET D 3631 measuring equipment with N1ATG8/Cmeasuring probe by the Comet System company. Other analogue sensors to measure humidityand temperature were independently installed for checking. The monitoring was each timecarried out for 24 hours. During storage both the temperature and humidity of the hops in thecontainer increased substantially, with temperature values reaching up to 49 °C and humidityvalues 100%. The progress of temperatures was almost identical with all the measurements, thatis why we present only the average values. The highest temperature inside the container was inthe range of 39 °C to 49 °C with individual measurements. The temperatures of the checksamples were identical with the air temperature in the daytime with all the repeats. Themaximum temperature of the check samples ranged from 21 °C to 27 °C with eachmeasurement. In the same way as with the temperature, during the individual measurements thehumidity showed similar progress and the measurements did not differ from each other in anysubstantial way. The humidity level in the container rose up to the maximum value of 100%already two hours after the measurement had started and stayed like this until the end. Thehumidity of the hop check samples was 2.24% higher than the air humidity, which might beexplained by water vapour emission due to an increased intensity of hop cones breathing. Theconclusion we may draw here says that with an increasing volume and, probably above all,height of the stored hops layer, the influence of the surroundings on the conditions inside thecontainer will decline.

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427-431 A. Valiuškaitė, N. Kviklienė, D. Kviklys and J. Lanauskas
Post-harvest fruit rot incidence depending on apple maturity
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Post-harvest fruit rot incidence depending on apple maturity

A. Valiuškaitė, N. Kviklienė, D. Kviklys and J. Lanauskas

Lithuanian Institute of Horticulture, Babtai, Kaunas distr., LT-54333,Lithuania; e-mail: a.valiuskaite@lsdi.lt

Abstract:

The effect of fruit maturity on apple storage ability and rot development wasinvestigated in 2003–2004 at the Lithuanian Institute of Horticulture. Two apple cultivars ‘Ligol’ and ‘Lodel’ on M.26 rootstock were tested. Fruits were harvested 5 times at weekly intervals and were stored for six months in cold storage. Maturity index was calculated at each harvesting.Fruit quality parameters and rot incidence were evaluated after 90, 150 and 180 days ofstorage. While in storage ‘Lodel’ apple rot was caused by Monilinia sp., Gloeosporium spp., Penicillium spp., Alternaria spp. and Botrytis sp. Cv. ‘Ligol’ apples were infected by Monilinia sp., Gloeosporium spp. and Penicillium spp. Both tested cultivars were mostly infected by fungus of Gloeosporium genus. Cv. ‘Lodel’ was more sensitive to fungal rots.The time and intensity of rot incidence depended on cultivar, harvest date and climaticcondition during the vegetation. More rot injuries were detected on apples picked later. A significantly smaller number of rotten apples was recorded in apples picked at optimum maturity. Cold and wet weather during the ripening period determined an earlier and significantly higher occurrence of fungus during storage.

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