جستجوی مقالات مرتبط با کلیدواژه "بهبود کیفیت" در نشریات گروه "صنایع غذایی"

One of the most important applications of biotechnology in the food industry is the production of various additives. Among the additives produced by biotechnology method is the production of exopolysaccharides produced by bacteria in dairy products.Diversity in the structure and chemical composition of microbial exopolysaccharides has made them superior to animal and plant polymers. Due to these cases, these compounds can be used as food additives with health effects. In the present study, Bacillus bacteria producing exopolysaccharides were isolated from the soils of desert areas and then, the structural and functional groups of exopolysaccharides were identified using FT-IR method. The presence of peaks in the frequency range 400-4000 (cm-1)indicates the polysaccharide and purity of the extracted material. Then, their effects on the quality of yogurt were investigated. Based on the results, the quality of yogurt samples containing exopolysaccharide of bacteria K, C, B, A and E significantly increased compared to the control group that did not contain exopolysaccharide.Exopolysaccharide from E bacterium significantly reduced hydration compared to other samples and control samples and also significantly increased the viscosity and water holding capacity and consistency of yogurt. Finally, based on the 16S rDNA sequence, the bacterium whose exopolysaccharide had the greatest effect on improving the quality of yogurt, Bacillus wiedmannii strain HBUM207173 was identified.

The aim of this research was to compare the benefits of wheat enrichment in the farm with flour fortification in the factories. Three experiments have been carried out in the early of third Millennium in 6 different provinces، i. e. East and West Azerbaijan، Kerman، Sistan and Balouchestan and Southern Khorasan. The first and second experiments (2000-02 and 2002-04)، were designed based on t-distribution and included two treatments: The control plots were given nutrients based on Farmer''s conventional fertilization practice (NP) and the treated plots received nutrients based on soil tests (balanced fertilization) in Meyaneh (3 wheat farms) and Naghadeh (1 wheat farm) in East and West Azerbaijan provinces. In the wheat fields، micronutrient-fertilizer solution with 0. 5% was sprayed at three stages (stem elongation، heading، and a week after flowering). After harvesting، the grain yield، phytic acid، Zn and PA/Zn molar ratio were measured. Then، whole-wheat bread and regular bread prepared from these farms were fed for 4 and 6-month periods to different groups in Tajark، Khanghah and Kahriz villages in East and West Azerbaijan، respectively. Before and after feeding the village inhabitants، zinc (Zn) and iron (Fe) concentration were measured in their blood serum. In the third experiments، in the summer of 2003، a study on the effect of fortification and improvement of the quality of bread on the health of consumer subjects was carried out on the total personnel of Moghadam Mersad Military Station. A number of the drafted military service personnel of Moghadam Mersad Military Station and some personnel from Ravar Aboozar Military Station were selected for blood tests. During a 4-month test period، bread consumed at the Station and the associated units was fortified and the correct procedure of baking was taught to the bakers. The amount of Zn and Fe in the blood serum of the subjects was determined with an atomic absorption spectrometer. Fortification of the wheat flour was carried out at the Baghin Martyrs Station، by adding، 80 mg Zn; 50 mg Fe; 10 mg vitamin B1; 2. 5 mg Vitamin B2; and 5 mg vitamin B6 per kg of flour. In the first and second experiments، the results demonstrated that there was a significant difference at one percent level for grain yield (α=0. 01). Also، the statistical analysis revealed a significant difference for phytic acid، Zn and molar ratio of phytic acid to Zn (PA/Zn) in all wheat farms. Consumption of whole wheat bread in comparison with white bread for 4 and 6-month periods noticeably increased Zn and Fe concentration in blood serum especially in 6-month period. While the average Zn and Fe concentration in the blood serum in the second experiment for the control was 80 and 100، they were increased to 110 and 130 μg/deciliters after the intervention in Kahriz village. In the third experiment، in places where bread was not fortified، the average level of Zn in the blood serum of individuals was measured to be 72 μg/deciliters; whereas، the serum Zn of the test subjects consuming fortified bread for a three-month period averaged 89 μg/deciliters (P<0. 01). For persons who fed on unfortified bread، 47% suffered from Zn deficiency but those who used the superior quality، fortified bread، only 10% suffered from this deficiency (P<0. 01). While the number of people using stomach-problem-related-medicines at the Beghin Martyrs Station during a 4-month period before the experiment was figured to be 1615، it was reduced to 1375 cases after the test; or a 15% decrease during a 4-month period. In conclusion it can be mention that superiority of the enrichment in the farm over flour fortification in the factory has been proven. Enrichment is preferred to flour fortification and its most important benefits are at least 20% increase in wheat yield as well as grain quality and more than 10% increase in minerals concentration due to more uptake by human''s digestion system.