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Changes in particle size, solubility and chemical structure of different fiber components can cause changes in the bioavailability of some nutrients. Numerous studies have shown a reduction in apparent digestion of proteins in the gastrointestinal tract caused by direct and indirect processes. Endogenous nitrogen losses are due to increased secretion of digestive juices and increased desquamation in the presence of dietary fiber. Food fibers reduce digestion of food and endogenous proteins. Food processing can improve the bioavailability of proteins. Reduction of thermally latent antinutritional factors, such as trypsin inhibitors, phytates and polyphenols, as well as partial denaturation of proteins by heat treatment contributes to their digestibility. Protein quality in processed foods decreases primarily due to reduced lysine bioavailability. Experiments revealed an increase in protein digestibility (PD) in whole wheat flour heated samples in a forced air oven at 150°C over 0-10 minutes: 31.8% at time 0, 43.73% at 5 minutes and 48.43% at 10 minutes of heating. When heating for 15 minutes, digestibility decreased to near the unprocessed sample value (33.8%). PD in wheat samples exposed to microwave for 30, 60 and 90 seconds increased throughout the entire time period, with a maximum of 45.06% when exposed for 90 seconds. PD increased moderately in whole barley flour samples heated at 150°C, from 27.46% for the unprocessed sample to a maximum of 33.47% for the 5 minutes heated sample. PD in barley samples exposed to microwave was higher than in the unprocessed sample, with a maximum of 36.34% for 30 seconds exposure. [ABSTRACT FROM AUTHOR]

Cereal grains are major sources of dietary fiber (DF), an important component of food and an important contributor to human health. Based on their water solubility DF are classified as soluble dietary fiber (SDF) and insoluble dietary fiber (IDF). The physical and physiological properties of dietary fibers are of commercial and nutritional importance. Food processing is mostly based on heating. Heat treatment alters the properties of plant cell wall and modifies the composition and solubility of fibers. The experiments had in view the effect of dry heat treatment (in forced air oven, and microwave oven) on the bioavailability of carbohydrates. The research investigated the dynamics of released glucose (RG) from heat treated whole wheat and barley flour, during in vitro gastric and intestinal digestion. RG after 240 minutes of intestinal digestion revealed a higher digestibility of carbohydrates in wheat samples heated at 150°C for 10 and 15 minutes and in barley samples heated for 5 minutes. When the heating time of the barley samples was longer, the digestibility of carbohydrates decreased due to the formation of higher starch resistant to amylase action. Carbohydrates digestibility of wheat samples exposed to microwaves was lower compared with untreated samples. We observed a moderate increase in carbohydrate digestibility in barley samples after microwave exposure for 30 and 60 seconds. The digestibility decreased after 90 seconds of microwave exposure, due to accelerated Maillard reactions and increase in the proportion of resistant starch. [ABSTRACT FROM AUTHOR]

The dynamics of released glucose (RG) and refractive index (RI) in the supernatant obtained during in vitro gastric and intestinal digestion of whole barley flour was studied. The in vitro digestion consisted of a two-step enzymatic procedure: (1) initial simulation of gastric digestion using pepsin and (2) simulation of small intestine digestion using multi-enzyme pancreatin. Experiments on 1 g barley flour showed an initial increase in RG concentration up to 0.379 mg / mL at one hour from the onset of gastric digestion, then a decrease in concentration, reaching the lowest value in 2 hours of gastric digestion (0.126 mg/mL). The concentration in reducing sugars increased throughout the intestinal digestion from 0.422 mg/mL up to 2.824 mg/mL, as a result of starch hydrolysis to dextrins, maltose and then to glucose. RI can give information on the amount of glucose released during digestion due to the high positive correlation found between RG and RI (r = 0.761). [ABSTRACT FROM AUTHOR]

Starch is the most important digestible polysaccharide present in foods and feeds. The starch concentration in cereals cannot be determined directly, because the starch is contained within a structurally and chemically complex matrix. Fine grinding and boiling in dilute HCl are preparative steps necessary for complete release of the starch granules from the protein matrix. Starch can be determined using simple and inexpensive physical methods, such as density, refractive index or optical rotation assessment. The polarimetric method allows the determination even of small starch contents due to its extremely high specific rotation. For more accurate results, the contribution of free sugars is eliminated by dissolution in 40% (V/V) ethanol. The influence of other optically active substances, which might interfere, is removed by filtration/clarification prior to the optical rotation measurement. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate changes in some physicochemical properties of milk during acidification. The milk samples were analyzed for titratable acidity expressed as % lactic acid (LA), pH, electrical conductivity (EC) and lactose content. In fresh milk LA and pH exhibit a weak negative correlation (r=-0.3210). When acid production starts, LA increases proportionally, whereas the pH decreases (r=-0.8043). The acidifying process induced concomitantly an increase in EC. The decrease in pH from 6.578±0.088 to 5.732±0.195, and in lactose content from 5.469±0.256g% to 4.97±0.385g% was accompanied by an increase in EC from 5.337±0.434 mS/cm to 5.940±0.493 mS/cm. [ABSTRACT FROM AUTHOR]

The aim of the present investigations was to determine the effect of the cold storage period on the content of chlorophylls in the leaves of lettuce and arugula (rucola). The research material consisted in two types of lettuce (Lactuca sativa L. var. capitata; Lactuca sativa L. var. crispa) and arugula (Eruca sativa) purchased from supermarkets in Timisoara. The quantitative determination of chlorophyll pigments in leaves (SPAD) was made by chlorophyll meter (SPAD 502 Konica-Minolta). During the few days cold storage at a temperature of 4°C, the content of chlorophyll in the leaf significantly decreased, compared with that in the control group. After 3 days of cold storage arugula and lettuce (Lactuca sativa var. capitata) values of chlorophyll content differ statistically very significantly (p<0.001) from the values found in the control group which for lettuce (Lactuca sativa L. var. crispa) differs statistically significant (p<0.05). [ABSTRACT FROM AUTHOR]

The research had in view to evaluate and compare two instrumental techniques used for the determination of milk lactose. Refractometric and polarimetric measurements were carried out on milk serum obtained after precipitation of casein by two different methods: by acidification of milk to its isoelectric point (E1), and by using copper sulphate and potassium ferrocyanide (E2). The average lactose content measured by refractometry was 5.469±0.256 g% for method E1 and 5.852±0.218 g% for method E2. The obtained average lactose values measured by polarimetry were higher both for E1 (5.613±0.253 g%) and E2 (5.910±0.224 g%) methods, due to the interference with other optically active components. The experimental data revealed a high correlation between the results obtained by refractometry and polarimetry (r=0.8712) when casein precipitation was performed by potentiometric titration until pH=4.6, at 25°C with 2N acetic acid (method E1). [ABSTRACT FROM AUTHOR]

The influence of physical factors, such as microwave radiations, is today an alternative in agriculture for stimulation of plant vitality. In this study, we aimed to evaluate the influence of microwaves in the early seedlings stages for 4 Romanian barley genotypes: Cardinal, Sistem, Dana and Maresal. This study was conducted to determine whether there are differentiated responses to microwave irradiation, at different powers and different exposure times, on the dynamics of root growth in some barley cultivars. Root growth measurements were performed after 3, 7 and 14 days of treatment with microwaves. It was observed that genotype, power or exposure time had significant influence both on root growth and on the number of roots of the studied barley genotypes. Microwave treatment caused significant differences in seedlings root growth. The greatest influence on root growth had the time of exposure. The best results in terms of root growth were obtained for the Cardinal and Sistem variety. At these varieties, we observed the best stimulation effect, and the lowest influence of the microwave action. The most affected genotype was Dana, with the lowest stimulation effect. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the total protein values obtained in heparin plasma of chickens by a spectrophotometric technique (biuret method), and the values obtained on the same day in the same samples by refractometry. The results obtained by refractometry (average value 2.638±0.153g%) were higher than those obtained by the spectrophotometric method (average value 2.441±0.181g%). There was a low correlation (r = 0.6709) between the total protein values, determined with both methods. Protein is the major determinant of plasma refractive index, but glucose contributes too. The refractometric method is not recommended in chickens for the determination of total protein, because avian blood glucose concentration averages about twice than in mammalian blood. [ABSTRACT FROM AUTHOR]

The objective of the present study was to investigate the changes induced upon germination and growth rate, expressed by vigor index of barley seeds exposed to microwave (MW) treatment. As a microwave source was used a magnetron MWG20H, which emits radiation with a frequency of 2.45 GHz. In the experiment, barley seeds were exposed for 0s, 10s and 20s. The germination energy (GE) and germination (G), cotyledon length (CL), leaves length (LL) and roots length (RL) in cm were determined on the 3th, 7th and 14th day after irradiation in order to estimate the influence of microwave treatment on them. The hypothesis was that seeds exposed to MW will behave differently than those unexposed. It was observed that the best results in terms of GE, G and vigor index (SVI) were obtained in barley seeds for the treatment with output microwaves power of 400W for 20s. [ABSTRACT FROM AUTHOR]

Ionized calcium is the physiologically active fraction of serum calcium and therefore its evaluation is an important clinical parameter both in mammals and birds. In the present study, concentration of total calcium (tCa), ionized calcium (iCa) based on the serum albumin level and on the total protein content, and corrected total calcium (ctCa) based on the serum albumin level were evaluated, and the correlation between these biochemical parameters was investigated in broiler chickens. The average serum iCa was 4.91±0.49g/dL representing 51.76±0.53% from the ctCa. The correlation coefficient between tCa and albumin (r = 0.8608) was greater than that between tCa and total protein (r = 0.7997). Our study illustrated that iCa and ctCa concentrations calculated from tCa and albumin are better indicators of calcium homeostasis than tCa concentrations alone. [ABSTRACT FROM AUTHOR]

Gynogenesis is a technique used to generate diploid individuals with genetic material exclusively of maternal origin. In this study we test the hypothesis that heat shock treatment of rainbow trout eggs, activated with UV irradiated sperms, leads to the generation of a uniform populations of diploid gynogenetic females. Activation of fertilized eggs with UV irradiated semen, by heat shock at 27.5°C for 10 min. directly after fertilization induces diploid gynogenesis. Diploid individuals are obtained at a rate of 73.33%. Triploid individuals are obtained at a rate of 26.67%. The enhanced number of triploid individuals may be due to insufficient irradiation of heritable material of sperm. [ABSTRACT FROM AUTHOR]

Taking into consideration that the vegetable oils added to the combined fodder can significantly modify the fatty acids profile in broiler food, through its redirection even the fatty acids profile of carcasses can be modified through enrichment in certain fatty acids and obtaining functional foods. Therefore an experiment was conduced on broilers, made up of three experimental groups, fed with a combined base fodder in which 2% of different fat sources have been incorporated (sunflower oil, soybean oil, linseed oil). After the 42 days growth period, the fatty acids profile, % of fatty acids in 100 g product (EPA, DPA, DHA), Σ SFA, Σ MUFA, Σ PUFA of the chicken from the experimental groups, were determined. Fatty acids were determined using gascromatography. The data obtained after statistic processing and interpretation have highlighted the fact that, concerning the fatty acids profile in the chickens breast, we can observe variations of the determined fatty acids content, what shows us that they can be influenced through dietary factors, but there quantity being determined by the participation % of the energy sources (vegetable oils), but also by the fatty acids content of the participating raw materials. [ABSTRACT FROM AUTHOR]

Energy sources, especialy vegetable oils, added to the combined fodder can segnificantly modefy the fatty acids profile of the chicken feed, thus through its control the fatty acids profile of the carcases can be modefied, through enrichment in some fatty acids. In this respect an experiment was coduced on broilers, made up of three experimental groups, fed with a combined base fodder (corn and soybean meal) in which 2% of different energy sources were added (sunflower oil, soybean oil, linseed oil). At the end of the 42 days growing period, using gaz cromatography, the fatty acids profile, % of fatty acids in 100 g product (EPA,DPA, DHA), Σ SFA, Σ MUFA, Σ PUFA from the studied cut pieces, were determined. The results obtained after statistc processing and interpretation of the data, showed the fact that regarding the fatty acids profile in chicken thigh and abdominal fat we can observe variations, what denotes that the fatty acids profile can be influenced by dietary factors, the quantity being yet determined by the participation % of the energy sources (vegetable oils), but also by the fatty acids content of the participating raw materials. [ABSTRACT FROM AUTHOR]

The aim of the paper was the study of embryos survival rate after eggs triploidy treatment in rainbow trout (Oncorhynchus mykiss Walbaum). The triploidy induction was preformed during the cold period of January when the water temperature reached 8-10°C and the environmental conditions inducted the natural reproduction of rainbow trout. The reproducers used for the experiments were between 3-5 years old. The spawn fertilization was made by the wet method. For each experimental lot higher losses have been observed at the end of the first, second, third and the middle of the fourth decade. The T1 experimental lot has registered the highest losses in the first decade while the T2 lot in the last decade. The losses registered for the T1 and T2 experimental lots during the spawn incubation were significant higher comparing to the control lot M as resulted by the statistical interpretation of data's. [ABSTRACT FROM AUTHOR]

Thermal treatment of cereal grains affects carbohydrate and micronutrient content and bioavailability. Water-retention capacity (WRC) is an important index for the effects of fiber in the diet and the metabolic activity of fiber along the gut. This study evaluated the effect of thermal treatment and digestive enzymes on wheat and barley WRC. Ground wheat and barley samples were heated for different time periods at 150°C before in vitro gastric and intestinal digestion. WRC values in heat treated wheat and barley are at higher levels as compared to the values of untreated cereals. WRC in barley ranged from 1.026 g water/g DM (untreated) to 1.36 g water/g DM (heated at 150°C for 15 minute). The increase was much lower in heat treated wheat, from 0.973 g water/g DM up to 1.03 g water/g DM at 5 minutes heating time. [ABSTRACT FROM AUTHOR]

The purpose of this paper work is to establish the correlations between soluble nonstarch polysaccharides (NSPs), insoluble non-starch polysaccharides (NSPi) and total nonstarch polysaccharides (NSPt) levels from combined forages with different barley inclusion percentage and viscosity at intestinal level. The experiment was made on a period of six weeks on 120 broiler chickens, hybrid ROSS 308, divided in four experimental lots: CL without barley in the structure of combined forage, EL1 with 10% respectively 20% of barley, EL2 with 20-30% barley and EL3 whit 30% and 40% barley in the first and respectively the second period of growth. The determination of intestinal viscosity was made at 3 and 6 weeks by slaughtering the chickens and sampling the duodenal and jejunum content. To establish the correlation between viscosity at intestinal level and the levels of non-starch polysaccharides from combined forages were used the simple correlation and curvilinear regression. At the age of 3 weeks the viscosity rises with the rise of barley inclusion percentage from combined forage and was with 33.65% greater at experimental lot with 10% barley and with 54.14% greater at experimental lot with 30% barley. It was found that the correlation coefficients between NSP content and the viscosity at duodenum level are positive, the greatest correlation coefficient was registered in the case of NSPs (0.92), which indicate that the digestion viscosity at intestinal level is influenced by the forage content in NSPs. At 6 weeks, at duodenum level the viscosity rise with the rising of barley inclusion percentage in the structure of combined forage and was with 64.67% greater at experimental lot with 40% barley in the combined forage. At 6 weeks the correlation coefficients between the NSP content and the viscosity at duodenum level respectively at jejunum level are positive, the greatest correlation coefficient was registered in the case of NSPs (0.998), which indicate that the digestion viscosity at intestinal level is influenced by the forage content in NSPs. [ABSTRACT FROM AUTHOR]