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Copyright of Firat Universitesi Saglik Bilimleri Veteriner Dergisi is the property of Firat Universitesiu, Saglik Bilimleri Enstitusu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ege Üniversitesi Ziraat Fakültesi Dergisi is the property of Ege Universitesi, Ziraat Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, dynamic rheological, textural, color and sensory properties of White cheeses produced from pasteurized milk at different conditions (A: 65 °C for 20 min, B: 75 °C for 5 min, and C: 85°C for 5 min) were investigated at 7, 30, 60, and 90 days of storage. The higher elastic behaviors of the cheeses C and B than A were associated with improved inter- and intramolecular interactions of casein related to the temperature and an increase in the ratio of denatured whey protein in this structure. Cheese A changed as the highest extent in viscoelastic property and complex viscosity parameter while cheese B was determined as more stable during storage. The results of hardness and adhesiveness in texture analysis confirmed that cheese B had a more resistant protein structure. The effect of different pasteurization temperatures on the color parameters was not found. The Structure-Texture as a sensory property of cheese B in the first months received higher scores while no differences among the samples in the last month were observed. As a result, White cheese with improved viscoelastic property could be produced from the milk pasteurized at 75 °C but increased temperature reduced this feature. [ABSTRACT FROM AUTHOR]

Both globally and nationally, a significant portion of milk obtained is processed into durable dairy products, of which cheeses are the majority. Today, cheese is made from raw and/or pasteurized milk. There are various risks of infection and intoxication caused by consumption of cheeses made of raw milk. For this reason, pasteurized milk is generally used in most of the cheeses industrially manufactured. Pasteurization process eliminates some of the deterioration factors such as spoilage and pathogenic microorganisms. Meanwhile, the most of lactic acid bacteria, which provide spontaneous acidification and maturation of cheese during cheese production, are also inactivated by this heat treatment. Therefore, it is a technological requirement to use starter cultures in cheese production in order to get a standard quality along with usual and desirable taste and aroma. In this review, general information about these starter cultures, used in cheese production, is presented. [ABSTRACT FROM AUTHOR]

In this study, the applicability of enzymatic modification of milk proteins by transglutaminase enzyme in production of Ayran and the effects of enzyme addition on the quality criteria of product, were investigated. For this purpose, the enzyme addition to Ayran milk at two different steps of the production (just after the pasteurization and simultaneous addition with starter culture) and in two different incubation time with enzyme (at 50 °C 1 hour and 10 minutes), were tried. Ayran samples were kept at 4 °C for 20 days and analyzed on the 1st, 10th, and the 20th days of the storage. As a result, significant increase in viscosity and decrease in syneresis were determined. In Ayran samples produced from enzyme-treated milk, It was detected that transglutaminase did not cause significant changes on chemical properties of Ayran. Electron microscopic studies showed that enzyme- treated milk lead to obtain firmer microstructure in Ayran. Amount of enzyme used in this study was 1 Unit TGase/g milk protein. It was also determined that usage of this amount of enzyme concentration made no significant change in the flavour component of Ayran. [ABSTRACT FROM AUTHOR]

In this study it was aimed to investigate the effect of different homogenization pressures (10 MPa and 20 MPa) and pasteurization (at 65 oC for 30 minutes) on the composition of White cheese and whey. Cheeses were produced according to traditional methods. Fresh cheeses and their whey were analyzed for chemical composition after production. Cheese yields and calcium contents of samples were also determined. Obtained actual cheese yields were converted into adjusted yield based on their average dry matter content. Adjusted yield of cheese increased in homogenized and pasteurized samples. While dry matter, fat and fat in dry matter content of cheese were higher; protein in dry matter and ash in dry matter of cheese samples were lower in homogenized samples. These results can be attributed to more retain rate of fat in cheese mass depending on homogenization pressure. Pasteurization process increased ash and calcium content of cheese samples. Consequently, it can be said that pasteurization and homogenization processes had positive effects on White cheese composition. [ABSTRACT FROM AUTHOR]

This study was conducted to determine effects of homogenization treatments under different pressures (150, 200 and 250 kg/cm2) on some physical, chemical, microbiological and sensory properties of ayran throughout the storage period of 1, 7 and 14 days. Whey separation of samples decreased while viscosity values increased with the increased homogenization pressure (P<0.05). It was identified that different homogenization pressures had no significant effects on chemical, microbiological and sensory properties of ayran samples (P>0.05). [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of ultraviolet light treatment on microbiological quality of milk. For this purpose, cow milk samples, which were obtained from five different milk producers, were applied ultraviolet treatment (UV) and pasteurization. Total aerobic mesophilic bacteria, coliform, E. coli, mould-yeast, Streptococcus spp. and Lactobacillus spp. counts were determined in the samples. It was found that effects of treatments on these microorganisms in raw milk were significant. The UV treatment was as effective as pasteurization on total aerobic mesophilic bacteria and coliform and a significant reduction was achieved. However, it was found that UV treatment was less effective on mould-yeast and Streptococcus spp. in milk. [ABSTRACT FROM AUTHOR]

Extension of the shelf life of refrigerated products requires, at a minimum, reductions in the growth rate of spoilage microorganisms and subsequent deterioration of the product. Reduction of initial bacterial loads coming from the raw material, improvement of pasteurization regimes, and reduction of pre-process contamination have all been employed with measured success for increasing the shelf life. The use of antimicrobial additives has been discouraged primarily due to labeling requirements and perceived toxicity risks. Carbon dioxide (CO2) is a naturally occurring milk component and inhibitory toward dairy spoilage microorganisms; however, the precise mechanism is not fully understood. CO2 addition through modified atmosphere packaging or direct injection is used world wide commercially as a cost-effective and favored process for the extension of shelf life of dairy products. New CO2 technologies are being developed for the improvement of the shelf life, quality, and yield of a diverse range of dairy products, including cheeses, cottage cheese, yogurt, butter and fermented dairy beverages. In this study, a comprehensive review of past and present researches related to quality improvement of such dairy products using CO2 is presented. [ABSTRACT FROM AUTHOR]