Search
Search Results
-
The change of the inner content parameters of table beet (Beta vulgaris L. ssp. esculenta Gurke var. rubra L.) as a result of storage
113-119Views:169The stored vegetables play a key role in the vegetable consumption. After harvesting, the storage conditions greatly affect nutritional parameters of the crop. The red beet is a root vegetable, which is manufactured mainly fresh in our county, therefore we do not have enough information about the storage. In our experiment, 5 varieties (Rubin, Akela, Larka, Libero, Mona Lisa) were examined in prismatic structure (0–5 °C and 95–97% RH) through 5 mounths.
Our measurements proved that under the appropriate storage conditions water loss was also occurs, which increased the dry matter content (average of 0.5 g 100 g-1). The bioactive compounds, like pigments (betanine and vulgaxanthin) and the quantity of flavonoids, were significantly increased during the experiment.
The results showed that the nutritional parameters of the 5 types was positive during the prismatic structure. However, this storage method negatively affected the bioactive compounds of the Akela genotype. Further studies are recommended for proper storage parameter adjustment, which is justified by the need of the different varieties. The optimal conditions enable us to preserve and to increase the best nutritional index.
-
Storage of wheat at high moisture
111-114Views:74Deterioration rates were determined for 15-19% moisture content wheat (Dropia cultivar) stored at constant temperatures.
Deterioration rates were determined by measuring germination capacity of the grain and respiration rates of grain. Safe storage
time was defined as the time for germination to decrease to 90%. Safe storage times of 19% m.c. wheat stored at constant
temperatures ranged from 2.5 d at 30 and 35°C to 37 d at 10°C. Deterioration rates of 19% m.c. wheat stored with a step decrease
in storage temperatures (35-25, 30-20, 25-20, and 20-15°C) were determined and safe storage times were satisfactorily predicted.
Safe storage times of 17% m.c. wheat were 5, 7, and 15 d at 35, 30, and 25°C, respectively. Respiration rates and germination
percentages of 15 and 16% m.c. wheat stored at 25°C remained constant for 70 d. The respiration rates of 17-19% m.c. wheat at
25°C increased while the germination percentages decreased with storage time. Germination dropped from 98 to 92-89% when the
dry matter losses were about 0.05% and visible mould occurred when the dry matter losses were about 0.1% in 17-19% m.c.
wheat. -
Variations in major quality parameters of forage and medium quality winter wheat varieties in storage
249-254Views:92We analysed five parameters (moisture-, protein content, Hagberg’s falling number, wet gluten content and alveographic W (10-4 J) values) and the microbiological changes of four forage and milling III. quality winter wheat varieties (Magor, Hunor, Róna and Kondor) during storage, to determine the tendency, type and volume of the of the change of this five qualitative parameters during storage.
We found that the examined winter wheat varieties retained their moisture, protein content and their Hagberg’s falling number, they did not change during storage.
A slight growth could be experienced in the values of wet gluten content for all the four winter wheat varieties in terms of the duration of storage (129 days). This result proved the theory of after-ripening, when gluten percentage improves qualitatively and quantitatively as well. The value of the quantitative growth was about 10% for all the four winter wheat varieties.
We placed a special emphasis on measuring the alveographic W (10-4 J) values during storage. All the four winter wheat varieties showed decreasing values of about 20-40%.
Microbiological examinations on the four winter wheat varieties showed that mould, mould flora and total germ count remained balanced with some slight variations and they did not change in terms of time under optimal storage conditions. -
Development of the antioxidant indexes (FRAP, TFC, TPC) of scabbing resistant apple varieties in storage
89-94Views:132One of the most important groups of bioactive substances in apples are antioxidants, which have a health-preserving effect. The amount of these compounds varies not only during the ripening of the apple fruit, but also continuously during post-harvest storage. A growing group of health-conscious consumers are looking for apple varieties with a nutritional value that satisfies their needs.
In the scope of our research, we examined 5 apple varieties originating from the Derecske horticultural site of KITE cPlc. in 2016. The plantation was planted to be suitable for intensive apple production. Samples were collected at the time of maturity (August-October) of the given variety. The 5 examined apple varieties (Gaia, Isaaq, Modí, Smeralda and Fujion) are all resistant to apple scab (fungal disease caused by Venturia inaequalis). The 2-month storage experiment was conducted at 16–17 °C, which had an aggressive effect on our stored apples. Total polyphenol (TPC) and flavonoid (TFC) content as well as FRAP values of the apples were measured. Measurements were taken immediately after harvest and after 1 and 2 months of storage. Our results were evaluated by using the IBM SPSS Statistics 20 software. Our aim was to compare the antioxidant results of 5 scab-resistant apple varieties, which change continuously during storage.
The antioxidant content of our apple varieties increased during 2 months storage. The best result was achieved by the Modí apple variety (FRAP: 467.32 mg/100g; TFC: 317.76 mg/100g; TPC: 1771.97 mg/100g). Consumers may want to consume apples stored for a longer period of time if they are to absorb large amounts of antioxidants.
-
The effect of short term storage on different winter wheat varieties rheological properties
83-86Views:153The aim of storage after harvest is to protect the quality of wheat, because after-ripening occurs in the first 5–6 weeks. During this time it very important to make the optimal storage conditions.
We have carried out storage experiment with wheat samples from Látókép Research Farm of the University of Debrecen. We analyzed the rheological parameters of Lupus and GK Csillag varieties from the crop year 2011/2012. The experiment period was between July and August 2012 (24. 07. 2012., 31. 07. 2012., 21. 08. 2012.).We determined the rheological parameters (water absorption, dough stability time and valorigraph quality number) of Lupus and GK Csillag during short term storage. Our results showed that after-ripening increased the baking quality of Lupus and GK Csillag during storage.
-
Effect of Ozone Exposure on Phytopathogenic Microorganisms on Stored Apples
9-13Views:93The aim of our study was to clarify the effect of ozone exposure on several phytopathogenic fungi on stored apple fruits under different storage conditions. The study was conducted at Bistrita, Romania, in the storehouse of an experimental apple orchard in 2002 and 2003. Two widely grown apple cultivars (‘Jonathan’ and ‘Golden Delicious’) were used. General microbial examination of the fruits was made during storage in order to identify the most important storage pathogens. Efficacy of six ozone treatments was evaluted on fruit decay caused by phytopathogenic fungi. Monthly observations (January, February, March and April) were made of the degree of decay and three measurements were assessed (disease frequency, disease intensity and degree of attack). Our results showed that the most important phytopathogenic fungi during storage was blue mold, caused by species of Penicillium. Disease frequency of apple fruits was very high on cv. ‘Jonathan’, much higher than on cv. ‘Golden delicious’. Ozone treatments (25 ppm ozone for 0.5 and 1.5 hours in November) caused significantly lower disease incidence on stored apple than all other ozone treatments. For longer storage, it seems that additional ozone treatments in February increased treatment efficacy. Cv. ‘Golden delicious’ seemed to be more resistant to storage diseases than cv. ‘Jonathan’ both on the untreated and treated fruits. The effect of the ozone treatments was also the most effective when 25 ppm ozone was applied for 0.5 and 1.5 hours in November.
-
A new model for predicting carbon storage dynamics and emissions related to the waste management of wood products: introduction of the HWP-RIAL model
75-81Views:93The ability of wood products to store carbon allows for their significant contribution to the climate mitigation efforts and the emission reduction commitments set by the EU. In order to optimise the carbon storage capacity of wood products, it is important to take climate mitigation aspects into consideration as much as possible during their production, use and waste management. The aim of this study was to quantify the effects of product development, recycling, and waste management technologies on carbon storage and emissions. In the frame of the ForestLab project, a new model and decision support tool was developed, which is able to predict the duration of carbon storage of wood products and the evolution of emissions from them. The developed HWP-RIAL model (Harvested Wood Product Recycling, Incineration And Landfill model) uses the methodology of the Intergovernmental Panel on Climate Change (IPCC) to calculate emissions, which is also used in the National Greenhouse Gas Inventory report. It combines the IPCC waste model with equations describing the carbon storage and emissions of wood products, and the model is also supplemented with a self-developed recycling and waste routing module. This paper provides insight into the operation of the model by following the life cycle of 200,000 m3 particle board.
-
Flesh firmness examination of scab-resistant apple varieties in a storage experiment
93-98Views:119Of the different physical characteristics of fruits, one of the most essential qualities is flesh firmness, as is an important parameter when selling fresh apples, processing the fruit (processing industry) and during its storage. In the scope of our research, we examined five apple varieties originating from the Derecske horticultural site of KITE cPlc. in 2016. The plantation was planted to be suitable for intensive apple production. Samples were collected at the time of maturity (August-October) of the given variety. The five examined apple varieties (Gaia, Isaaq, Modí, Smeralda and Fujion) are all resistant to apple scab (fungal disease caused by Venturia inaequalis). The two-month storage experiment was conducted at 16-17 °C, which had an aggressive effect on our stored apples. Flesh firmness, weight and diameter were measured on three dates for each of the five apple varieties. Our results were evaluated using IBM SPSS Statistics 20 software. We aimed to compare flesh firmness, weight and diameter of the five apple varieties and their changes during storage. Isaaq (86.34 N/cm2), Modí (94.06 N/cm2) and Fujion (84.90 N/cm2) had outstanding initial flesh firmness results. The Modí apple variety provided the best storage parameters.
-
The examination of flesh firmness in different apple varieties
103-107Views:174Of the different physical features of fruits, one important quality feature is flesh hardness. This is an important parameter to be considered when selling fresh apples, for the manufacturing industry and when entering into storage. In our research, we examined 7 apple varieties, in 2016 and 2017, from the establishment of KITE Zrt. in Derecske and the Horticultural Experimentation Site of Pallag (Pallagi Kertészeti Kísérleti Telep). The plantations took place in accordance with intensive apple production. In both years, samples were collected at the time ripening of the given apple variety. Of the examined apple varieties, 5 of them are resistant to scab (Gaia, Isaaq, Modí, Smeralda, Fujion), 1 is not resistant (Golden Reinders) and 1 (Pinova) is moderately susceptible to scab. The scab resistant apple varieties were correlated to the non-resistant Golden Reinders. Flesh firmness was measured with a fruit penetrometer in each of the seven apple varieties. In the first year a two-month storage experiment was carried out, where the flash firmness after harvest, and after one-month and two-month storage was measured. The results were assessed with the help of the IBM SPSS Statistics 20 program. The goal is to compare the apple varieties based on their flesh firmness, in particular with regard to the resistant varieties.
The Isaaq 8.81–8.82 N/cm2 , the Modí 9.18–9.59 N/cm2 and the Fujion 8.66–9.13 N/cm2 , all of which are scab resistant apple varieties, showed a significant initial flesh firmness. During storage, the Pinova apple variety flesh firmness changed the most favourably.
-
The economicalness of apple production in view of post harvest technology
125-131Views:184This study analyses how the level of postharvest technology’s development influences the economic efficiency of apple production with the help of a deterministic simulation model based on primary data gathering in producer undertakings. To accomplish our objectives and to support our hypotheses three processing plant types are included in the model: firstly apple production with no postharvest and prompt sale after the harvest, secondly parallel production and storage combined with an extended selling period and thirdly production and entire postharvest infrastructure (storage, sorting-ranking, packing) with the highest level of goods production and continuous sales. Based on our results it can be stated that the parallel production (plantation) and cold storage, so the second case is proved to be totally inefficient, considering that the establishment of a cold storage carries enormously high costs with resulting a relative low plus profit compared to the first type of processing plant. The reason for this is that this type is selling bulk goods without sorting-grading or packaging; storage itself – as a means of continuously servicing the market - is not covered properly by the consumers. Absolute efficiency ranking cannot be established regarding the other two processing plants: plantation without post-harvest infrastructure resulting lower NPV, but a higher IRR, DPP and PI as developing a plantation and a whole post-harvest infrastructure. Former processing plant type is favourable considering efficiency ratios describing capital adequacy, while the latter is in terms of income generating capacity.
-
Evaluation of egg quality parameters of two Hungarian ostrich populations
51-57Views:198The aim of our study was to evaluate the quality parameters, porosity and weight loss of eggs deriving from the two most significant ostrich farms in Hungary. Quality parameters included weight, length, width, shape index, egg volume, surface area, circumference and shell volume. The effect of storage conditions in both farms and the incubation technology on egg weight loss in farm “A” were also examined. The research objective was to impart a comprehensive knowledge on egg quality parameters of the main ostrich populations in Hungary and to compare the trios and the farms with each other and the international literature. We could reveal significant differences between trios in all egg quality traits. In conclusion, the shorter and the narrower the eggs were, the more spherical shape they had. Narrower eggs showed smaller surface area, volume, circumference and shell volume and vice versa. Eggs from farm “B” indicated significantly greater width, shape index, surface area, circumference and shell volume than farm “A”. A significant difference was observed in weight loss during storage between the farms. Weight loss in farm “A” was a multiple of farm “B”. In farm “B” there was a weak, positive correlation between storage period and weight loss (r=0.22, P≤0.05), in farm “A” it was not significant (P=0.52). There was no relationship between the initial egg weight and weight loss either in farm “A” or farm “B” (P=0,21, P=0,69). A slight positive correlation could be noted between egg porosity and weight loss (r=0.24, P≤0.05). Pores count presented here was less than the international results. Poultry eggs contain the most pores at the blunt end, less via the equator and the least at the pointed end. In ostrich egg we found more pores via the equator against the blunt end. To draw more precise conclusions, further investigation should be carried out on porosity. Considering the fact that the length of storage period and the weight loss during incubation are in strict correlation with hatchability, we intend to extend our research aims to these traits.
-
A tárolási feltételek hatása a kukorica Fusarium fertőzöttségére és toxin szennyezettségére
28-32Views:195Corn samples harvested in 1997, 1998 and 1999 from different soil types were stored at different conditions (temperature, moisture content, state of kernels) for six months. The Fusarium contamination was examined by plate dilution method and the amount of mycotoxins (F-2, T-2, HT-2, DON, DAS) were determined applying HPLC method immediately after harvesting and in the third and sixth month of storage. The aim of our study was to find correlation between the ecological factors, storage conditions and the examined parameters mentioned above, as well as to prove them statistically. According to the examinations carried out after harvesting we could state that the soil type had no effect on the parameters. Analysing the effect of the years we found considerable differences. The Fusarium infection of corn samples in 1998, while the toxin contamination in 1999 was the highest. The results of storage experiment show that year (number of microscopic fungi, F-2, T-2, HT-2, DAS and total toxin content) and moisture content of kernels (F-2, T-2, and total toxin content) have a significant effect on the examined parameters. We could prove the effect of temperature on the T-2 content (samples with natural moisture content) and DON content (samples with 14% moisture content). Higher values were found at higher temperature storage. The ratio of damaged kernels influenced the DON concentration in the non- wetted samples and the number of microscopic fungi in the wetted samples.
-
Changes in the Quality Parameters of Wheat Samples of 16% Moisture Content during Storage
117-121Views:60We have carried out storage experiments with wheat varieties Magvas, Fatima, Mv Emma and Mv Pálma from the 2001 growth year. During the first half of the experiments quality parameters, such as changes in moisture, protein and gluten contents as well as pharinograph readings, falling numbers and sedimentation indices were analysed and tested at an average initial moisture content of 13%.
The findings in the changes in the quality parameters of different wheat varieties with 13% moisture content as a function of storage time duration were published in an earlier paper of mine (12/04/2002).
This paper wishes to give an account of the second part of the storage test when the moisture contents of the different varieties were raised to 16% and the changes in the quality parameters were monitored for seven weeks. The findings show that contrary to what had been experienced in the first half of the trial, there were no changes in the protein contents, pharinograph readings, water uptake or Zeleny counts and falling numbers showed decreases with each of the varieties tested. -
Effect of Storage on Fruitquality of Apricot (Prunus Armeniaca)
164-169Views:96The quality of a product is determined by numerous characteristics. As quality characteristics are polygenic, they cannot be improved easily. Moreover, there often is a negative correlation between the different parameters in the case of apricot. The firmness of fruits decreases with increasing size. The year effect also has a great influence on the expression of the potential quality of the given cultivar.
Our examinations were carried out in 2004 at Boldogkőváralja, in the cold storage plant of the Northcot Ltd. We monitored the development of fruits from fructification until harvest, and also the quality changes during storage. 100 fruits were observed from each cultivar directly after harvest. We measured height, width, weight, firmness, dry matter content and seed weight. From each cultivar, 100 fruits were stored, of which 25 fruits were observed each week. The value and the dynamics of the changes in the parameters compared to the values at harvest varied greatly for the different cultivars. Strong correlations between the parameters have not been found within one cultivar either. The heavier fruits did not lose more weight, either in absolute value or relatively, than the lighter fruits. The increase in the firmness of fruits was not accompanied with a desirable decrease in the dry matter content. -
Effects of ingredients and processing conditions on the quality frozen dough bread made from diferent wheat flour
115-120Views:67A laboratory scale no-time frozen dough procedure that approximates Romanian commercial practice has been
developed and used to study the effects of ingredients and processing conditions on the bread quality of a straight
grade wheat flour during prolonged storage (2 days to 26 weeks). All treatments (baking absorption level, mixing
energy input, mixer type, fermentation and intermediate proof times, removal of oxidant and/or dough
strengthening conditioners and partial freeze-thaw cycles) had significant effects (P<0.05) upon bread quality (loaf
volume and/or bread score). In general, these effects were more pronounced with extended frozen storage time.
High baking absorption, undermixing, bulk fermentation (> 1 h) and removal of oxidant and/or surfactants had
the most dramatic effects. Addition of a very strong flour at 30% to strengthen the wheat flour had no significant
effect (P>0.05) upon bread quality under optimum conditions. -
The parameters of homemade jams after storage
39-42Views:136Nowadays producing jams is considered a traditional way of plum processing in Hungary. Plum jams without added sugar can be stored
This research aimed to analytically determine which quality parameters of the jams and to what extent they change during storage. Furthermore, this study intended to find out whether a concious consumer can presume any difference between varieties or the year of harvest, or wheather a one-time customer should suspect differences in quality parameters of the different products. This study focused on those differences or alterations in the parameters that occur in the jams made from several different plum varieties produced in different years.
I analyzed the classic chemical parameters (dry matter content and ash content) and physiologically important nutritional components (phenolic and flavonoids antioxidants and vitamin C). In this research I used jams which were produced from 6 varieties grown in 2009 (President, Tophit, Bluefre, Elena, Presenta, Stanley), 4 varieties from 2010 (President, Bluefre, Elena, Presenta) and 6 varieties from 2011 (President, Tophit, Bluefre, Elena, Presenta, Stanley). Jams were produced with traditional technology in cauldrons without added sugar. Jars were placed into a relatively dark and cool place and were stored there until the analysis.
Having regard to the results, when consumers choose between the different products they also choose quality since the processed plum variety, and the year of production/processing determine the nutritional value of the specific product. This could be used for market positioning and promotion of the product, however further research is needed to gain more information from the differences that derive from the varieties, year of harvest or other factors. This way fruit and jam producers could turn these informations into market advantage.
-
Storage of ram semen in gelatin supplemented extender
7-10Views:117The aim of our study was to examine how different gelatin concentrations affect ram semens viability in liquid storage at 5 oC for five days. Our hypothesis was if we add gelatin to the semen extender, than the viability of ram semen will be better in the extenders containing gelatin, than the control. We used two different semen extenders:1.5% UHT milk and 1.5% UHT milk + 5% egg yolk. We added 0; 0.5; 1.0; 1.5; 2.0% Dr. Oetker gelatin to the semen extenders. We stored the semen for five days at 5 oC and in every 24 hour we made sampling.
We stained the smears with Kovács-Foote staining and evaluated them with light-microscope. We categorized the cells in five groups like: live and intact cells, live cells with injured acrosome, dead cells, live head with dead tail and live tail with dead head. We used one-way analysis of variance (ANOVA) to assign how gelatin concentration affects the number of the categorized cells. On the fifth day, the viability was the best in the following semen extenders: 1.5% fat UHT milk + 1.0% gelatin and 1.5% fat UHT milk + 1.5% gelatin, but it was not significant (p>0.05). -
Global Issues of RangelandManagement
39-46Views:99Rangelands occupy about 50% of the world’s land area. They are ecologically and economically as important as rain forests and in even greater danger of degradation and disappearance. This paper reviews the definitions and distribution of rangelands and describes their global environmental importance in terms of erosion control, carbon storage and methane emission. Condition and degradation of rangelands are defined and discussed and it is argued that soil protection and carbon storage can be increased and methane emission per animal decreased by conservative use and improvement of rangelands, whilst at the same time alleviating hunger and malnutrition in developing countries. It is concluded that policies should be adopted by national governments and international deve-lopment programs to conserve and improve rangelands.
-
The Dg RES generation, storage, utilization and integration program ’1 village – 1 MW’ of the Bükk-Miskolc Region, Phase 1–3.
233-235Views:84The usage of renewable energy sources (RES) and the increase of energy efficiency could be the solution for the difficulties of the rural impoverished inhabitants. A rural development company with the support of the communities designs the development resources from the EU and the Hungarian State for RES generation and organizes the ’1 village – 1 MW’ RES generation, storage, distribution and usage integration.
-
The factors affecting the proliferation of mould fungi and mycotoxin production during the storage of wheat and the identification methods of the appearing branches
129-133Views:120Nowadays, it is often suggested that, we should eat products made with whole grain cereals, despite of the fact that it raises the risk of consuming wheat products infected by mold and their toxins originated from the plough-lands and the stocks.
Two third of the cultivated fields in Hungary are planted with cereals. The most alarming problem for food and feed security is caused by the Fusarium species. The greatest problem of all is caused by the mycotoxins. When they get into the food chain they can be a serious threat to public health. In addition, we have to face up to the problem of the effects of global warming that influence the growth of microbial infections in different ways.
In this article we tried to summarize the effect of climate change on molds, the factors which have effect on growing and mycotoxin producing of molds and the identification methods of molds. -
Determination methods of quality parameters of Prunus cerasus
107-111Views:138Sour cherry (Prunus cerasus) is a non-climacteric fruit. Storage optimization would enable the expansion of fresh consumption. The quality parameters are required for storage optimization. Those parameters are sugar content, acid composition, mineral content and alcohol content,
moreover it is also planned to determine antioxidants, vitamins and patulin mikotoxin under different conditions. In this paper, we demonstrate the measurement options of these parameters. -
Effect of the storage temperature onto the quality of the semen of rams of different breeds
75-79Views:114Semen of 10 Tsigai,3 Prolific Merino and 7 Barbados Blackbelly rams was taken in January, out of the season. Split samples of the diluted semen samples were kept at 23, v.s. 8oC and their motilitywas evaluated daily for 3 days by subjective microscopic investigation. The ratio of motile spermatozoa was strongly decreased during the first day, later the motility rate was sinking more slowly. It could be stated by multivariance analysis that the motility value of diluted semen of Prolific Merino rams was higher and showed a slower reduction as compared to the other two breeds. The decrease of the motility rates was slower at 8oC than at 23oC.
-
Data supporting the quality of sheep milk for processing
67-73Views:82Although the volume of ingredients in ewe’s milk is substantially higher than in cow’s milk, its hygienic quality is lower. The weak quality of raw ewe’s milk limits the possibilities of processing and results in bad quality products. In our investigation we analysed the state of ewe’s milk processing at a typical medium size dairy firm. We investigated the collection, the amount and the quality of milk and the level of ingredients in milk throughout the purchasing period (lactation period).
The purchasing of ewe’s milk was limited to 5 months (from April to September). Although meat (lamb) provides the major source of income to sheep breeders the extension of the period of ewe’s milk production can be beneficial to shepherds and dairy firms. The amount of ewe’s milk ingredients found corresponded to published findings. However, the hygienic quality of ewe’s milk was varied greatly in the different milk samples and these deviations meant bad quality on average. Physiological factors, the circumstances of sheep breeding and milking, the slow cooling of the milk, the little amount of daily milk and the long storage before transportation to the dairy firm together cause poor hygienic quality. The main problem is the long storage time of milk, but our results raise the question of reconsidering the quality classes. Investigating the effect of the hygienic quality of raw milk on product quality, we can get correct data that can be really authoritative. -
Effect of raised level α-linolenic fatty acid diet on broiler meat quality
29-33Views:83The aim of our investigation was to determine the effects of increased α-linolenic content in food on the colour, total pigment content, organoleptic characteristics and oxidative stability of poultry meat. The experiment was carried out with 1200 Ross-308 cock chicklings. Birds were fed three-phase diets, contained four different fat sources: lard, sunflower oil, flaxseed oil and soybean oil. According to the experiment, the different oil sources had no effect on growth performance, but the fatty acid composition of diets was reflected in the meat fatty acid profile. We could detect just slight change in colour in the treated meat, which was not caused by the decreased pigment content. The detected change in colour during the storage was not in relation to initial PUFA content. TBA level did not prove the accelerated lipid peroxidation which was expected in case of higher α-linolenic containing the meat. The data obtained in meat storage trial, could not prove clearly the negative effect of the higher α-linolenic content of the meat.
-
The composition of gluten proteins and their effect on the rheological properties of gluten
124-129Views:119Wheat is the major cereal component of bread in the world and is grown worldwide. Of the cereals only the bread wheats – and less the triticale – includes storage proteins that play an important role in the performance of gluten. Proteins of gluten complex may be present in two classes:
− low molecular weight (gliadin-) components, and
− high molecular weight (glutenin-) components.
Gliadins shown appreciable heterogenity and can be separated into 40-50 components with gel electrophoresis. The composition of gliadins is employable for the identification the wheat varieties and to investigate the varieties. In the decreasing electrophoretic mobility sequence may be distinguish α-, β-, γ- and ω-gliadins. A glutenin subunits may be include in two classes:
− high molecular weight glutenin subunits (HMW-GS),
− low molecular weight glutenin subunits (LMW-GS).
Wheat varieties can be identified by glutenin and their quality selection is also possible. The gliadin’s polypeptides encoding genes are located on the short arm of chromosomes 1A, 1B and 1D, 6A, 6B and 6D. Genetic coding for HMW subunits is located on the long arms of chromosomes 1A, 1B and 1D, the LMW-GS are also located on chromosomes 1A, 1B and 1D (Glu-3 loci) near the gliadin-coding loci.
Storage proteins affect the rheological properties of gluten by two factors:
1. The quality and quantity of the protein components of the gluten complex,
2. The interactions between the protein fractions.