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Baking quality and protein composition of emmer wheat landraces
2008
Konvalina, P., University of South Bohemia, Ceske Budejovice (Czech Republic). Faculty of Agriculture | Moudry, J., University of South Bohemia, Ceske Budejovice (Czech Republic). Faculty of Agriculture | Moudry, J. jr., University of South Bohemia, Ceske Budejovice (Czech Republic). Faculty of Agriculture
Emmer wheat, Triticum dicoccum SCHRANK (SCHUEBL), is an old species of cereal which has been traditionally grown in arid areas. The renewed interest in this variety has its origin in favourable quality parameters of emmer wheat grain and a beneficial effect on human organism. This article deals with a study of quality parameters and storage protein composition of 6 varieties of emmer wheat (which have been chosen from the collection of gene bank at the Research institute of Crop Production in Prague-Ruzyně and in České Budějovice). High crude protein content in grain was proved during the trials. Nevertheless, such a characteristic is not suitable for the classical bakery processing (production of leavened products). The analysed genotypes contain more than 10% of high molecular weight glutenins (HMW glutenins), approximately 70% of low molecular weight glutenins + gliadins (LMW glutenins + gliadins), and almost 20% of residual albumins and globulins. Thanks to high share of albumins and globulins, emmer wheat grain is very valuable raw material for the production of healthy diet. The level of stability of storage proteins composition destines the suitability of emmer wheat for organic and low input farming in Less Favoured Areas.
Show more [+] Less [-]Quality changes during summer–autumn long-term storage of Scots pine (Pinus sylvestris L.) roundwood
2016
Magaznieks, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Millers, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gzibovska, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
Latvia at the moment does not have precise data about long-term storage of Scots pine. Long-term storage in warm season may lead to significant damages for high priced timber, income reduction for timber sellers and quality loss risk for timber buyers, therefore, roundwood is transported as soon as possible, because of the risk of blue stain, crooks and insect damages. Results of this study on Scots pine were obtained during summer–autumn season of year 2015. Scots pine timber quality changes in long-term storage were analysed in 4 sample stacks – set up in summer (25 July) and stored for 100 days. In every sample plot there was a control pile, a pile with harvester spike damages, a pile with bark damages and a pile with harvester spike and bark damages. There were 32 timber assortments in every pile in order to determine also the emplacement effect in stack. In this study a high correlation was found between pine timber quality changes and meteorological conditions, side surface damages and storage length. By analysing the proportion of blue stain in cross-section and its changes during storage between control assortments and assortments with bark and harvester damages, significant differences were observed, therefore it can be concluded that not only bark damages influence the proportion of blue stain, but also harvester spike rollers. Based on the results of this study, we can predict maximum storage duration during summer–autumn period in Latvia, and it is set from 9 – 16 days.
Show more [+] Less [-]Incidence of postharvest rot of cranberry (Vaccinium macrocarpon Ait.) in Latvia
2012
Vilka, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Bankina, B., Latvia Univ. of Agriculture, Jelgava (Latvia)
The American cranberry (Vaccinium macrocarpon Ait.) is a perspective and marketable crop both in Latvia and foreign markets, but berries are affected by rot in storage. The aim of the study was to detect the incidence level of cranberry fruit rot at the beginning of storage period in different places in Latvia. In 2007 - 2011, two hundred sound berries (out of 1000) were randomly collected by hand along a diagonal from five different cranberry plantations from locations all over Latvia. Berries were kept in plastic bags for a month and refrigerated at +7 °C. At the end of November, berries were sorted and rotten berries were separated from the sound ones. Over the period of 2007 - 2011, the incidence of storage rot reached 12 - 15% at the end of November, with an upwards trend observed every year, but the hot and rainy summer of 2010 significantly reduced the quality of fruit in storage, peaking on the average 33% of decayed berries. The incidence of fruit rot varied among the inspected cranberry plantations, but a tendency was observed that older plantations produced more rotting fruit and incidence of the disease was 12 - 50% after a month’s storage in the oldest plantation. The application of fungicides during the vegetation season did not affect development of post-harvest rot. Storage rot was a problem in the cranberry samples from all inspected plantations in Latvia, and in future the incidence of fruit rot is expected to increase.
Show more [+] Less [-]Investigations into the enhancement of cow's milk oxidative stability
2012
Antone, U., Latvia Univ. of Agriculture, Jelgava (Latvia) | Sterna, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Zagorska, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
The quality and nutritional value of milk and dairy products are considerably influenced by the stability of its constituents. The aim of the present study was to evaluate the possibility of enhancing oxidative stability of cow’s milk fat and vitamin B2 using carrots and palm oil feed supplement CAF 100 as sources of natural antioxidants in cow feed. Milk samples were collected after 25-day period of feed supplementation. The intensity of riboflavin losses during its photo oxidative degradation in sunlight was measured by the fluorometric method. A slight and significant (p is less than 0.05) difference in higher vitamin B2 stability was seen in carrot-supplemented group (TG1) milk, where the losses of vitamin B2 were by 3.01% less compared to CG (CG). The oxidative stability of butter oil samples stored in 60 °C temperature was analyzed by peroxide value (PV) method. The oxidative stability of samples initially affected by light from both trial groups was significantly (p is less than 0.05) higher compared to CG showing the good potential of the cow diet enrichment with carotenoid additives. The longest induction period (larger than 14 days) was observed in CAF-100- supplemented (TG2) cow milk fats, which can be explained by carotenoids and tocopherol presence and its possible synergism in fat protection. The induction periods of the TG1 and CG were 12.03 and 10.97 days, respectively.
Show more [+] Less [-]Quality changes during summer – autumn long term storage of birch (Betula pendula) roundwood
2017
Magaznieks, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Millers, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gžibovska, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
The homogeneous and light wood of birch is suitable for different types of treatment processes and is highly valued for products where visual aspect is important, however, birch assortments are highly susceptible to damages caused by fungi during the storage. Such fungal damages cause discoloration of birch roundwood intended for further woodworking. Sapwood discoloration development and its influencing factors for birch roundwood were analyzed in the summer - autumn period of the year 2016 (August, September and October). Control cut for assessment of sapwood discoloration development was made in four birch roundwood stacks in the districts of Auce and Daugavpils. In order to evaluate the influence of harvesting type, side surface damages, placement in pile, storage duration, diameter, distance from the end plane, daily average temperatures, precipitation amount and relative humidity on development of sapwood discoloration, 616 discs from birch log end planes were prepared. After conducting multiple factor linear regression, it was concluded that a significant development of discoloration and its changes for birch roundwood are promoted by harvesting type, placement in pile, distance from the end plane, daily average temperatures and relative humidity (R2 = 0.450). For birch logs that are prepared by harvester with the daily average air temperature + 6 °C, the first signs of discoloration appear after 17 – 18 days, but on all logs stacked in pile they appear after 68 – 69 days. Whereas, with the daily average temperature of + 18 °C, the first signs of discoloration can occur after only six days, but on all logs stacked in pile they appear after 23 days.
Show more [+] Less [-]Blue stain development of Scots pine (Pinus sylvestris L.) roundwood and its influencing factors
2017
Millers, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Magaznieks, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gzibovska, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
The normal wood colour changes due to the biochemical reactions as well as under the fungal exposure. Some of these fungi during all the exposure time cause only a discoloration (staining fungi); others change not only colour, but also the structure of the wood in its further development (wood destructing fungi). The development of blue stain in sapwood of pine roundwood and its influencing factors were studied in the spring summer period of 2016 (April, May and June) in the districts of Nica, Jelgava and Daugavpils. 650 discs from pine log end planes were prepared in order to evaluate the influence of harvesting type, spreading type of fungi spores, placement in pile, storage duration, diameter, distance from the end plane, daily average temperatures, precipitation amount and relative humidity on blue stain of sapwood and rot development. The most important factors influencing the blue stain development on pine roundwood during the storage are the harvesting type of roundwood, spreading type of fungal spores, placement in pile, storage duration, diameter, and distance from the end plane, daily average temperature and amount of precipitation. By evaluating the daily average temperatures, it was concluded that blue stain of sapwood begins to develop when the average daily temperature reaches +5...+6 °С. But when the average daily temperatures reach +10 °С, depending on the harvesting type (chainsaw or harvester) and spreading type of the fungal spores (via air or bark beetle assistance) the first signs of blue stain may occur from 10 to 42 days of storage.
Show more [+] Less [-]Effect of salt treatment on yield and quality of frozen cod loins
2019
Liorancas, V., Klaipeda State Univ. of Applied Sciences (Lithuania)
Study has been performed in fish processing plant ‘X’ with an aim of on purpose to investigating the influence of salt treatment on yield and quality of frozen cod loins. Samples were soaked in 0.8, 1.2, 10% NaCl concentrations in brine before being frozen. In this study, the cod loin’s weight loss during refrigeration, defrosting and cooking was calculated and sensory analysis was carried out. It was found that the soaking in brines affected higher weight of cod loins after freezing. In the control group it decreased by 1.14%, but the S0.8, S1.2 and S10 groups had the weight gain, respectively 3.41, 4.72 and +4.78%. Although after the defrosting and cooking the control group had the lowest weight losses, considering the losses of all operations, it was found that the largest weight loss was in the control group and in the S0.8 group, respectively 31.19% and 31.29%, while the lowest in the S1.2 and S10 groups – 30.49 and 30.06% (p is less than 0.05), respectively. Salt treatment did not affect the taste and odour, but improved the cod loin’s texture properties. Based on these results, salt treatment is considered as an effective way to improve the yield and quality of frozen cod loins.
Show more [+] Less [-]Changes in cold pressed rapeseed oil quality in different packaging materials during storage
2007
Bluka, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Cakste, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
The dynamic of rapeseed oil oxidizing processes under the influence of light in brown glass, colourless glass, and colourless PET bottles during storage at 18+-2 deg C were investigated. The changes in A and E vitamins content in rapeseed oil packed in colourless PET packaging materials were determined after 4 months storage at 18+-2 deg C at daylight. The connection between different packaging materials' transparency and oxidizing of oil were observed.
Show more [+] Less [-]Antiradical activity of vegetable oils
2006
Vucane, S.
This research presents the antiradical activity and fatty acids changes of vegetable oils. Natural antiradical activity and its changes during storage for one and two years of rapeseed, linseed and hemp oils were determined with 1.1-diphenyl-2-picrylhydrazyl (DPPH). Fresh hemp oil shows the higher antiradical activity. The content of fatty acids of fresh rapeseed, linseed and hemp oils and of the mixture of rapeseed (800 g kgE-1) and linseed (200 g kgE-1) oils was determined by the method of gas chromatography. After heating the mixture of rapeseed and linseed oils at the temperature of 160-180 deg C, changes proportions in saturated and unsaturated fatty acids.
Show more [+] Less [-]Impact of agroecological conditions on the Hagberg falling number of winter wheat grain
2015
Linina, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ruza, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Grain quality adversely affects price and consumer acceptance of finished products. Hagberg falling number (hereinafter falling number) is one of the most important grain quality indices of winter wheat (Triticum aestivum L.), especially in humid climate countries (Northern Europe). Field experiments with winter wheat cultivars ‘Bussard’ and ‘Zentos’ were conducted at the Latvia University of Agriculture, Study and Research farm ‘Peterlauki’ during a three year period (from 2009/2010 to 2011/2012). The aim of this investigation was to clarify variation of the falling number (FN) depending on cultivar, weather conditions and different rates of nitrogen (N) fertilizer applied (N 60, N 90, N 120, N 150) on fresh and stored grain (60, 120 and 360 days). During the investigation period, wheat ‘Zentos’ grain was characterised by a higher falling number compared with ‘Bussard’ grain. The falling number values for fresh grain for both wheat varieties studied were high: averagely 301 s for ‘Bussard’ and 359 s for ‘Zentos’, and reached demands set for grain suitable for bread baking. Differences in the falling number values were noted when freshly harvested winter wheat grain was compared with grain stored for 60 or 120 days and 360 days. During storage (60 – 360 days), α-amylase activity in winter wheat grain reduced and the FN increased on average up from 94 to 110 s. The falling number significantly depended on weather conditions, grain storage period and nitrogen fertilizer. The higher was the falling number of freshly harvested grain, the higher its increase during grain storage of compared to freshly harvested grain with a lower falling number value.
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