Tag Archives: sugars

876-886 N. Pedro, R. Bezerra, I. Fraga and A.P. Duarte
Production of simple sugars from olive grove pruning using acid pretreatment and enzymatic hydrolysis
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Production of simple sugars from olive grove pruning using acid pretreatment and enzymatic hydrolysis

N. Pedro¹²*, R. Bezerra³⁴, I. Fraga³⁴ and A.P. Duarte⁵⁶

¹Polytechnic University of Castelo Branco, Faculty of Agriculture, Department of Natural Resources and Sustainable Development, Quinta da Sra. de Miércoles, apartado 119, PT6001-909 Castelo Branco, Portugal
²QRural - Qualidade De Vida No Mundo Rural, Av. Pedro Álvares Cabral, n.º12, PT6000-084 Castelo Branco, Portugal
³UTAD - University of Trás-os-Montes and Alto Douro, Quinta de Prados, PT5000-801 Vila Real, Portugal
⁴CITAB - Centre for the Research and Technology of Agro-Environmental and Biological Sciences. UTAD, Quinta de Prados, PT5000-801 Vila Real, Portugal
⁵UBI - University Beira Interior. Convento de Sto. António, PT6201-001 Covilhã, Portugal
⁶CICS-UBI - Health Sciences Research Centre, University Beira Interior,
Av. Infante D. Henrique, PT6200-506 Covilhã, Portugal
*Correspondence: npedro@ipcb.pt; lnova@ipcb.pt

Abstract:

The purpose of this paper was to optimize the production of simple sugars from olive grove pruning (OGP) using acid pretreatment and enzymatic hydrolysis. This study was based on a model composition corresponding to a 34 orthogonal factorial design and employed the response surface methodology (RSM) to optimize the pretreatment and hydrolysis conditions, aiming to attain maximum glucose, xylose and arabinose extraction from cellulose and hemicellulose of biomass. The pretreatment operating conditions considered for optimization, were temperature (60–180 °C), residence time (30–120 min) and sulphuric acid concentration (0.5–5% w w-1). Enzymatic hydrolysis experiments on solid fraction pretreated with diluted acid were performed at a solid concentration of 5% (w v-1, based on dry weight), using 50 mM citrate buffer pH 4.8 with BSA at a concentration of 60 mg g-1 dry biomass. The reaction mixture was incubated at 50 °C for 174 h on an orbital shaker at 150 rpm. Three commercial enzyme preparations (cellulase complex, b-glucosidase and xylanase) were used in enzymatic saccharification. Total carbohydrate content of the initial biomass was 51.25% (in dry mass), of which glucose was the major constituent with 33.59%. Contents of lignin and extractable found in biomass were 24.96% and 15.84%, respectively. In this work, it was possible to extract 93.1% of the sugars present in the olive grove pruning, with pretreatments carried out for 102 min at 156 °C with a sulfuric acid load of 4.09% (w w-1), followed by enzymatic hydrolysis performed for 174 h, with an enzyme loading of 18 PFU, 36 p-NPGU and 36 IU per gram of substrate.

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1266-1274 V. Polishchuk, D. Konovalov and А. Brovdi
Influence of weather conditions on winter wheat(Triticum aestivum L.) overwintering
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Influence of weather conditions on winter wheat(Triticum aestivum L.) overwintering

V. Polishchuk¹, D. Konovalov² and А. Brovdi¹*

¹Uman National University of Horticulture, Faculty of Forestry and Landscape Gardening, Instytutska Str., UA20305 Uman, Ukraine
²Institute of Plant Physiology and Genetics the National Academy of Agrarian Sciences of Ukraine, 31/17 Vasylkivska Str., UA03022 Kyiv, Ukraine
*Correspondence: abrovdi@ukr.net

Abstract:

The aim of the study was to determine the effect of hydrothermal conditions, duration of winter and varietal characteristics on the sugar content in tillering nodes and, accordingly, on wintering of м plants in the Right-Bank Forest-Steppe of Ukraine. The direct dependence of the amount of sugars in the tillering nodes of winter wheat (Triticum aestivum L.) on the sum of effective temperatures and the duration of autumn vegetation was established. It was found that under the most favorable conditions prevailing in the autumn growing season of 2019, with the sum of effective temperatures of 984.6 °C and the duration of the autumn growing season of 76 days, the amount of accumulated sugars was 4.7% higher compared to 2016, and was 30.6%. It was found that over the years of research, the sugar content in the tillering nodes of winter wheat (Triticum aestivum L.) was higher in mid-season varieties, but there was no significant difference in varieties within the same maturity group, which confirms the high adaptability of the studied varieties to the soil and climatic conditions of the Right-Bank Forest-Steppe of Ukraine. Favorable climatic conditions in autumn and winter over the years of observation ensured good growth and development of plants in the pre-winter period and contributed to the accumulation of optimal amounts of sugars in tillering nodes, which ensured high winter survival of plants of all winter wheat (Triticum aestivum L.) varieties. The lowest percentage of overwintering was observed in Gorodnitsa variety at 98.8%, and the highest in Astarta variety with an average of 99.8% over the years of research.

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814-826 L. Shevchuk, Y. Tereshchenko, Y. Vintskovska, L. Levchuk, S. Babenko and R. Hrynyk
Yield and content of biologically active substances in blue honeysuckle fruit (Lonicera caerulea L.) grown in the Forest Steppe of Ukraine
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Yield and content of biologically active substances in blue honeysuckle fruit (Lonicera caerulea L.) grown in the Forest Steppe of Ukraine

L. Shevchuk¹²*, Y. Tereshchenko², Y. Vintskovska², L. Levchuk², S. Babenko² and R. Hrynyk²

¹National University of Life and Environmental Sciences of Ukraine, Agrobiological Faculty, 15 Heroes of Defense Str., UA03041 Kyiv, Ukraine
²Institute of Horticulture of the National Academy of Agrarian Sciences of Ukraine, 23 Sadova Str., UA03027 Kyiv, Ukraine
*Correspondence: zberig@ukr.net

Abstract:

The blue honeysuckle (Lonicera caerulea L.) is a relatively new crop in Ukraine, its industrial cultivation is only 100 hectares. The main constraints are the lack of varieties with high yield and nutritional value of berries. Therefore, a study of the yield and quality of introduced varieties is necessary and relevant, both for producers and breeders. With our research, we determined the potential of the early stage of blue honeysuckle berries under the conditions of their cultivation in the Forest Steppe of Ukraine and the weather conditions of the year of the specified region. We assessed how early we can get a crop and set what quality and what it will be. To clearly understand the quality of the grown fruits, their average weight, size and uniformity were studied. From nutritional indicators of fruit quality, the content of dry matter, soluble solids, sugars and titrated acids was studied, from biologically active substances, the content of vitamin C and total phenolic was determined. It was found that in the zone of the Forest Steppe of Ukraine from the studied group of varieties, the highest yield potential, 3.13 kg from a bush for the second year of fruiting and fruit mass 2.4 g, had a variety of Canadian breeding ‘Boreal Beauty’. The fruits of the cultivars ‘Duet’ (4.3) and ‘Boreal Blizzard’ (4.5) were distinguished by the balance of taste according to the sugar-acid index, and the maximum amount of total phenolics for the studied group of varieties was accumulated by the fruits of ‘Boreal Beast’ (1,000 mg 100 g-1).

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427-432 K. Laos , E. Kirs , R. Pall and K. Martverk
The Crystallization Behaviour of Estonian Honeys
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The Crystallization Behaviour of Estonian Honeys

K. Laos¹ ², E. Kirs¹ ², R. Pall¹ and K. Martverk¹

¹Department of Food Processing, Tallinn University of Technology, Ehitajate tee 5, EE12086 Tallinn, Estonia; e-mails: katrin.laos@ttu.ee; evelinkirs@gmail.com; praili@hotmail.com; kaie.martverk@ttu.ee
²Competence Center of Food and Fermentation Technologies, Akadeemia tee 15B, EE12618 Tallinn, Estonia

Abstract:

The feasibility of water activity and viscosity measurement was studied to characterize the isothermal crystallization of Estonian honeys. In parallel, samples were observed by light microscopy. The most important phenomenon for crystallization is the fructose/glucose ratio in favour of glucose. The increase in water activity and viscosity was noticed during crystallization. Polarized light microscopy was more sensitive than water activity or viscosity for determining the crystallization time.

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31–36 M. Jalakas, K. Kelt and K. Karp
The yield and fruit quality of sea buckthorn (Hippophae rhamnoides L.) after rejuvenation cutting
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The yield and fruit quality of sea buckthorn (Hippophae rhamnoides L.) after rejuvenation cutting

M. Jalakas¹, K. Kelt² and K. Karp¹

¹Institute of Horticulture, Estonian Agricultural University, Kreutzwaldi 64, 51014 Tartu, Estonia; e-mail: kkarp@eau.ee
²Polli Horticultural Institute of the Estonian Agricultural University, 69104 Karksi-Nuia, Estonia; e-mail: asta@pai.neti.ee

Abstract:

The yield and fruit quality of 6 sea buckthorn (Hippophae rhamnoides L.) cultivars of a Moscow breeding programme were studied at the Rõhu Experimental Station in South Estonia. The chemical contents of fruits of sea buckthorn were analysed after 3 months of cold-storage at –18°C. ‘Trofimovskaya’ appeared to have more sugars (2.9%) than the other cultivars. ‘Otradnaya’ had the lowest acid content (2.1%). ‘Vorobjevskaya’, ‘Trofimovskaya’ and ‘Otradnaya’ had higher ascorbic acid contents (about 65 mg/100 g) than the other tested cultivars. ‘Vorobjevskaya’ gave the highest yield (9.6 kg/tree) in the 3rd year after cutting down the trees to 2.5 m height. In the following year, the yield of the experiment was significantly higher, whereas cultivars Trofimovskaya and Botanicheskaya had the biggest yields.

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