Potravinarstvo Slovak Journal of Food Sciences
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Plum (Prunus rossica Erem.) fruit field and laboratory researces depending on the scion-stock combinations
Get PDFThe results of the field observations and biochemical researches of plum (PrunusrossicaErem.) fruits grown in the garden of intensive type with agrogenic soil in row spacing are presented in the article. The fruits of plum breeds Kubanskaya kometa и Naidena were gathered from the trees grafted on different stocks. The influene of the stock on the trees productivity, the fruit weight and biochemical structure of the plum fruits were studied. Basic chemical analyses, ascorbic acid concentration, antioxidant activity and fruit ash content were determined. The variation limits of the parameters under study depending on the used stock were shown. The best degustation evaluation parameters were found at the combinations of Kubanskaya kometa on stocks OPA-15-2 and Novinka, Naidena on OPA-15-2 (more than 4,5 points). The high positive correlation (r= 0.92) was marked between solutable solids and sugars content.The researches about the stock influence on the plum fruits titratable acidity change we have not found.The correlation between AA and ascorbic acid content in the fruits was determined (r =0.7). The decreasing row of the elements content in the plum fruits ash is the following: K>P>Mg>Ca>Mo>Cu>S>Ni>Fe≈Si>Mn. The proportion of K is from 18.67 (Naidena/ОРА-15-2) to 27.48 (Kubanskaya kometa/Novinka); P from 3.35 (Kubanskaya kometa/seedlings P.cerasifera Ehrh. to 6.39 (Kubanskaya kometa/Novinka), Mg from 1.11 (Nnaidena/ОРА-15-2) to 2.43 (Naidena/seedlings P.cerasifera Ehrh.) and Ca from 0.39 (Naidena/13-11) to 1.85 (Naidena/OPA-15-2) mass % respectively. The proportion of the rest elements is not more than 1 mass %. Under the OPA-15-2 stock influence the trees productivity and the single fruit weight increased, solutable solids, sugars and ascorbic acid concentration in the fruit in comparison with standard stock by the seedling rootstock of alycha (PrunuscerasiferaEhrh. seedlings). While ingrafting by Novinka stocks the parameters under study decreased
The amino acid profile after addition of humic acids and phytobiotics into diet of broiler chicken
Get PDFThe aim of the study was analysed the effect of humic acids separately and humic acids in combination with phytobiotic as garlic and oregano powder on amino acid (AA) profile of the most valuable parts of Ross 308 chicken. A total of 200 pcs Ross 308 broiler chickens of mixed sex were randomly divided into 4 groups (n=50): control group (C) without supplementation, experiment group E1 (2% humic acids), E2 (80% humic acids and 20% garlic powder) and E3 (90% humic acids and 10% oregano powder). Fattening period lasted for 42 days and all groups were kept under the same conditions. After slaughter, the AA profiles of breast and thigh samples were determined. In comparison with control group, 6 out of 10 AA was significantly affected (p ≤0.05) by used dietary supplementation - Met, Cys and His in thigh and Leu, Phe, His and Arg in breast muscle. AA composition of breast muscle was positively affected mainly by humic acids and 10% oregano powder supplementation (E3), while thigh muscle by humic acids and 20% garlic powder (E2). The highest obtained AA in breast muscle was Leu (2.02 g.100 g-1) in E3 group and thigh muscle His (1.15 g.100 g-1) in E2 group (p ≤0.05). In conclusion, humic acids and 10% oregano powder supplementation (E3) elicited to the best AA profile of chicken breast muscle but also the worst AA profile in thigh muscle so the effect of such a supplementation is disputable. On the other hand, humic acids and 20% garlic powder supplementation resulted into slight increase of AA in both breast and thigh muscle (E2)
Healthy eating index and different fruit dietary habits in Slovak adult female
Get PDFThe healthy index is a tool for evaluation of nutrition recommendation aimed at prevention of chronic diseases. A lot of studies have been devoted to HEI of different aged groups of people but dates about Slovak population have been still missed. The goal of the study was to evaluate the Healthy Eating Index (HEI) in nutrition of adult female, determine their components in relation of parameters of anthropometry and body composition. Secondly, the research work was also aimed at the comparison of partial score HEI among groups of female with different fruit intake. Daily nutrition was evaluated by 24 hours dietary recalls. In set of female (average age 31.1 ±9.1 years) the average HEI index reached up 53.0 ±8.8 points in accord with medium degree of diet, it means dietary improvement has been highly recommended. In respect of all assayed components of index the best results achieved the variety of diet (8.8 ±1.3 points) and the worst the natrium intake (0.7 ±2.0 points). The average score for the individual components pointed to neccesary of increase in the grain intake and vegetable, on the other hand the intake of cholesterol, saturated fats and especially natrium should be decreased. The differences between groups with various intake of fruit (with recommended intake and insufficient intake) in the rest 9 components have not been proved as significant. The occurrence of risk values of body index, body fats determined by bioelectric impedance and android risk based on circumference of hips can not be considered between groups as significant. Average HEI has been in significance correlation with age (r = 0.240; p <0.05), circumference of hips (r = 0.2312; p <0.05) and body weight r = 0.1748; p <0.05). Future studies have been needed to evaluate diet according to the HEI in different groups of population in Slovakia
Qualitative parameters of protein gels from albumen base
Get PDFThe aim of this research was to monitor strength of egg albumen gels depending on addition additives - salt, sugar, corn syrup, citric acid, citric acid in combination with sugar, whey protein and apple fiber. The egg albumen gel was prepared under two temperature limits at 70 and 90 °C. The highest strengths of egg albumen gel were achieved at 90 °C in the albumen gel with the addition of 1% citric acid and 3.5% sugar with a strength of 7.38 N, with the lowest strength of 1.61 N being achieved with the albumen gel with 0.1% salt. For an egg albumen gel prepared at 70 °C, the strength ranged from 1.34 N (0.1% salt) to 6.63 N (1% citric acid + 3.5% sugar). On average, the pH of egg albumen gels ranged from 4.67 (1% citric acid + 3.5% sugar) to 9.05 (0.1% salt). For the strength of egg albumen gel and pH with additives of various additives at a given concentration, a statistically significant difference was found
Efect of intramuscular fat content on physical-chemical parameters of pork from Mangalitsa and their crossbreed
No full textThe aim of study was to evaluate the effect of intramuscular fat content on physical parameters and proximate composition in musculus longissimus dorsi (MLD) from Mangalitsa breed and Slovak Large White x Mangalitsa crossbreed. In the study, sixteen pigs of Mangalitsa and twenty-two pigs of Slovak Large White x Mangalitsa crossbreed were used. The pigs were reared under intensive condition and all animals were fed ad libitum with complete fattening feed mixture. The fattening period started from 30 kg of live weight. Then the pigs were slaughtered at 100 kg of live weight. Chemical analysis showed that MLD from Mangalitsa had lower protein content, higher moisture content (p <0.05) and higher content of intramuscular fat compared to Slovak Large White x Mangalitsa crossbreed. As regarding the cholesterol content in MLD, no significant differences were found between genotypes, but the cholesterol content was higher in MLD from Mangalitsa than in MLD from crossbreeds. The MLD from Mangalitsa exhibited lower CIE L* (p <0.01) and CIE b* (p <0.01) values 45 min post mortem compared to crossbreeds. Colour parameters increased after 7 days post mortem, which is normal due to the maturing process of the meat. Then the CIE L* value was lower in MLD from Mangalitsa (p <0.01), but CIE a* value was higher in relation to crossbreeds (p <0.05). As regards the Warner-Bratzler shear force, the meat from Mangalitsa was tenderer than in crossbreeds (p <0.05). Intramuscular fat in the meat positively correlated with colour parameter CIE a* (r = 0.324; p <0.05) as well as cholesterol content (r = 0,656; p <0.001). In contrast in the study was found negative correlations between intramuscular fat in meat with moisture content (r = -0.399; p <0.05) and protein content (r = -0.812; p <0.001). It can be concluded that the percentage of intramuscular fat significantly influenced the physical and the chemical parameters of pork. The meat from Mangalitsa is more suitable for production of special meat products (fermented and smoked)
Characterization of fruit trees pollen
Get PDFOne of the options to determine botanical origin of trees or honey is the analysis of pollen grains. The characteristics of pollen grains in Czech flora has not been sufficiently described yet. Within this work, fruit trees pollen of Czech origin was characterized on the basis of morphological and spectral description of pollen grains produced by fruit species of M. domestica, P. armenica, P. persica, P. domestica, P. avium and P. cerasus. The morphological characterization results of the studied fruit species are consistent with results by other authors, but certain differences between the pollen grains of some fruit trees were confirmed. Most morphological differences were confirmed among the Malus and Prunus genera. Results of morphological and spectral analyzes further confirmed the differences between some types of fruit trees, but homogeneity remained for individual species even in mixed samples. Morphological and spectral analysis can therefore be used for botanical identification of pollen. If this knowledge is applied to pollen analysis in honey, these methods can also be used to verify the botanical origin of honey
Genetic diversity in Tunisian castor genotypes (Ricinus communis L.) detected using RAPD markers
Get PDFCastor (Ricinus communis L.) is a plant that is commercially very important to the world. It is produced in about 30 countries lying in the tropical belt of the world. It is an important plant for production of industrial oil. Assessment of genetic diversity of a crop species is a prerequisite to its improvement; hence it is important to identify the genetic diversity of castor genetic resources for development of improved cultivars. The present study is focused on estimation of genetic distance between 56 Tunisian castor genotypes, based on 18 RAPD markers. Seeds of castor were obtained from the University of Carthage, National Institute of Research in Rural Engineering, Waters and Forests (INRGREF), Regional Station of Gabí¨s, Tunisia. The ricin genotypes were obtained from 12 regions of Tunisia. The efficacy of the RAPD technique in this study is further supported by the obtained PIC values of the primers used in the analysis. PCR amplification of DNA using 18 primers for RAPD analysis produced 145 DNA fragments that could be scored in all 56 genotypes of Tunisian castor. The number of amplified fragments varied from 3 (OPE-07) to 13 (SIGMA-D-01), and the amplicon size ranged from 100 to 1500 bp. Of the 145 amplified bands, 145 were polymorphic, with an average of 8.11 polymorphic bands per primer. The lowest values of polymorphic information content were recorded for RLZ 9 (0.618) and the the highest PIC values were detected for OPD-08 (0.846) with an average of 0.761. A dendrogram was constructed from a genetic distance matrix based on profiles of the 18 RAPD primers using the unweighted pair-group method with the arithmetic average (UPGMA). According to analysis, the collection of 56 Tunisian castor genotypes were clustered into five main clusters. Genetically the closest were four genotypes from cluster 1 (BT-1 - S-5 and K-1 - N-3). Knowledge of the genetic diversity of castor can be used in future breeding programs for increased oil production to meet the ever increasing demand of castor oil for industrial uses as well as for biodiesel production
Comparison of analysis and the nutritional value of fresh common carp, frozen and southern canned tuna
Get PDFFreezing and canning are suitable methods to delay the spoilage of marine products and improve their physico-chemical and organoleptic properties. The fish were transported to the ice in proportion to 1 to 3 (w/w) inside the boxes, and then moved wastes. The purpose of this project is to analyse and to compare the nutritional value of fresh, frozen the fish and canned tuna fish. Nutrient composition and pH of the fresh fish fillet and moisture and ash contents and other nutrient composition were measured by the standard AOAC method. The results showed that the percentage of frozen fish protein was 17.41 and the highest moisture percentage for frozen fish with 72.23. The level of energy (kcal) of canned fish with 393.36 kcal was the highest level. The pH of the canned fish with 7.28 was the highest pH. The percentage of drip and WHC in frozen fillet found 6.7% and 6% respectively. From the obtained results, it can be concluded that despite the low amounts of protein and ash in canned fish, the fat and energy content was the highest. The protein content of the fish is frozen, and its pH indicates that it was better than fresh fish from point of quality
Physico-chemical study of steroids from different matureness corn silk material
Get PDFThis study shows an ultrasonic assisted extraction procedure of steroids from corn silk (CS). The total steroids contents were positively correlated with the ultrasonic assisted extraction time. The extracted steroids contents varied according to the different maturity stages of CS. There were three tested CS maturity stages: silking stage (CS-S), milky stage (CS-M) and mature stage (CS-MS). The β - sitosterol standardization method with 530 nm wavelength colorimetric measurements were applied to determine the content of extracted steroids. Measured steroids concentrations range were from 38.3 × 10-3 mg.mL-1 to 368.9 × 10-3 mg.mL-1 in different extraction time and CS maturity stages. The highest concentration of steroids, 368.9 × 10-3 mg.mL-1 was found in CS-MS sample with the 75 minutes ultrasonic extraction time. The fluorescence mapping techniques were used to confirm the existence of steroids. The thermal analysis illustrated a typical multistep decomposition process for the CS-S, CS-M and CS-MS samples. Two endothermic peaks were found: The first one was 54.3 °C for CS-S and CS-MS, 60.2 °C for CS-M, the second one, 397 °C (CS-MS), 415.1 °C (CS-M) and 419.7 °C (CS-S) attributed to the total thermal decomposition. The observed exotheric process found at 524 °C corresponded to CS-MS sample decomposition. The optimal ultrasonic-assisted extraction time for all samples under study CS-S, CS-M and CS-MS was about 75 minutes and the optimal steroids extraction contents obtained were 92.8 × 10-3 mg.mL-1 (CS-S), 124.2 × 10-3 mg.mL-1 (CS-M) and 368.9 × 10-3 mg.mL-1 (CS-MS) respectively
Characterization of compisote edible films from aloe vera gel, beeswax and chitosan
Get PDFEnvironmental consciousness as well as individual”™s demand for ready to eat food, recently, has changed the trends in food packaging leading to the development of biodegradable and edible packaging. Emulsified edible films have better transparency, superior mechanical properties and provide barriers to water and other atmospheric gases. Edible films if not consumed, biodegrad chemically. In present study, edible films were, initially, prepared using Chitosan and Aloe vera at different concentrations. Films were then subjected to physical and mechanical testing. Films with 20% Aloe vera had low thickness as compared to films with no Aloe vera. These films also had superior mechanical properties and lower water vapor permeability. Films with 20% Aloe vera were, then, selected and beeswax was dispersed in Chitosan-Aloe vera solution at concentration upto 2.0% followed by film preparation through casting technique. Thickness and water vapor permeability were observed to be improved with increase in concentration of beeswax. Tensile strength of edible films was also improved 1.3 times when concentration of beeswax increased from 0.5 to 2.0%. Percentage elongation decreased with increase in beeswax concentration in the emulsified films. No change in particle size was observed with change in concentration of beeswax. Emulsions were also stable at room temperatures. Decrease in transparency of emulsified edible films was observed with increase in beeswax content in the emulsified films. In addition, cost analysis of the films proved them reasonable to be used as an alternate of synthetic packaging materials