Treatment of Raw milk with CO2 as a procedure for preventing of microbial growth, control of psychrotrophic bacteria and extending of self life of milk products was studied using normal Raw milk, as control samples, and Raw milks treated with CO2 up to pH=6.4, 6.2 and 6. Experimental milk samples were stored for 10 days at 4oC and used for microbial assessment at 1, 5, 8 and 10 days of storing. The experimental design was split plot based on randomized complete blocks with four replications. Results showed adding of CO2 to Raw milk up to pH=6.2 and 6 inhibited significantly (P<0.05) microbial growth and those samples had a difference of 1.082 and 0.85 logarithmic unit in total count and also 1.089 and 0.923 in Psychrotrophic bacteria populations with control samples, respectively. It is concluded that adding of CO2 to Raw milk up to pH=6.2 and 6 can be considered as an effective pretreatment for preventing of increasing microbial population and preservation of Raw milk. Samples treated by CO2 with pH=6 had a self life of 3 days longer than control samples and was selected as the most effective treatment, although there were not significant differences in most parameters between pH=6 and pH= 6.2.

BACKGROUND: Microbiological and chemical qualities of milk are among the most important issues in public health.OBJECTIVES: Although there are a few published studies which have been conducted in south east of Iran this study was performed to investigate quality of Raw milk delivered to a dairy industry company Kerman Province.METHODS: Atotal of 109 Raw milk samples were collected at the time of delivering to the company. All the samples were transferred to the food lab of Veterinary School for total counting and psychotropic and Staphylococcus aureus counting. The chemical contents, residues of microbial inhibitors and Beta Lactam antibiotics residues were evaluated by Lactostar, Copan kit and Beta star test, respectively, and somatic cells were counted by a cell counter.RESULTS: Based on the comparison with national standard criteria, only 26 out of 109 samples (23.8; 95% CI: 16.2-33.0) were at standard limits in terms of all the factors. Alarge number of out-of-standard sample (50 out of 83), were in contrast with the defined criterion due to low protein.CONCLUSIONS: Classification of the samples based on all the defined criteria without considering protein content showed that the main problem of the milk was its low protein percent.

According to the international standards, presence of the antibiotics in the milk and milk products is not tolerated because it may initiate allergic reactions and other problems in the alimentary tract.On the other hand, presence of the antibiotics in milk interferes with the fermentation activities of the starter bacteria necessary in cheese, butter and other dairy products production. Presence of antibiotics in the Raw milk should be checked thoroughly in the pasteurization plants.Aminoglycosides, including gentamicin, are a group of antibiotics that are used in the treatment of mastitis in the milking and dry dairy cows in the form of systemic and/or local preparations. After using antibiotics, until the end of withdRawal time, almost all of them appear in the Raw milk. One of the best methods to determine presence of Gentamicin in the milk is ELISA which has high sensitivity and specificity. In the present study, 68 milk samples including 40 bulk tank Raw milk samples and 28 pasteurized milk samples have been tested by ELISA. Results of the test showed that total1y, 11.76% of both Raw and pasteurized milk samples were contaminated and 88.24% contained no gentamicin residue. In the contaminated milk samples, the highest concentration of the antibiotic was in the range of 0.63-1.25ng/ml of milk and the least concentration was in the range of 0.3- 0.625ng/ml. Antibiotic concentrations in the Raw and pasteurized milk were not significantly different (p>0.05). In order to have a more precise assessment of the results, supplemental lab tests were required (i.e. by use of HPLC) for reconfirmation of the results. Results of the experiment showed the necessity of the routine monitoring of milk and milk products for the detection of antibiotic residues.

Microbial communities play a fundamental role in shaping the taste, aroma, and texture of cheeses. They consist of starter and secondary microorganisms. Starters contribute to acid development during cheesemaking, while secondary microbiota play a crucial role in the ripening process. Their diversity is a subject of significant importance, shaped by various factors such as the cheesemaking environment, employed starters, physicochemical conditions, and manufacturing procedures. In this review, we attempted to provide an accurate picture of the microbial communities commonly found in Raw milk cheeses and tried to list their origins, factors influencing their existence, and the approaches used for their screening. The research employed information retrieval methods, mainly focusing on specific keywords. We systematically searched various databases for relevant articles and reviews, prioritizing the retrieval of the most recent publications and those deemed most relevant to the objectives of this review. This review disclosed the frequently identified bacterial genera in cheeses, such as Lactococcus and Lactobacillus. In terms of fungi, regularly isolated species included Candida, Kluyveromyces, Saccharomyces, Yarrowia, Goetrichum, among others. Our investigation enabled the unveiling of both the core microbiota shared across diverse cheeses, crucial for cheese fermentation and ripening, and the variable microbiota contributing to the diversity in cheese characteristics.

Consumption of food products of animal origin with residual antibiotic has become a major concern of public health and dairy industry. In the study, antibiotic residue in Raw and pasteurized milk was investigated. Of the 9 semi-industrial farm units, random on 3 occasions sampling was carried out from 4 milk collection stations and 3 pasteurized milk producing companies, and antibiotic residue was analyzed using Copan milk Test method. The results showed that of the 96 samples collected, 28 (29.16%) were positive in terms of presence of antibiotics residue. Analysis of milk samples taken in spring and in summer showed a significant difference in antibiotic residue content, such that samples taken in summer contained higher percentage of antibiotic residue (37.5%) compared to samples taken in spring (20.83%). Contamination of Raw milk samples (30.76%) with antibiotic residue was significantly higher than that in pasteurized milk samples (22.2%). Given the adverse effects of consumption of contaminated milk with antibiotic residues and huge losses to dairy industry, it seems more comprehensive studies are needed to ascertain precise types of antibiotic residues in milk consumed in this field.

Iodine is an essential trace element in the human diet. The following work presents the latest information concerned with iodine determination in Raw milk, in Iran. Iodine content of milk was determined by Sandell-Kolthoff method where the samples were taken from Holstein dairy cows, in Shahrkord, the central part of Iran. Thirty six samples were taken from transportation tanks in semi industrial farms (group 1) and 66 samples were taken from 66 cows in an industrial dairy farm (group 2). The mean iodine content of group 1 was 148.02±85.36  µg/L, where the minimum and maximum iodine concentrations were 20 µg/L and 289 µg/L, respectively. In group 2 the mean iodine content was 314.27±32.72 µg/L, where the minimum and maximum concentration were 227 µg/L and 378 µg/L, respectively. milk iodine concentration in group 1 is significantly different from the amounts obtained in group 2 (P£0.05). Mean iodine value of all the samples was 225.59±9792 µg/L. Mean iodine concentration did not changed in rainy and dry seasons. This study indicated that cow's milk might be an important source to provide the body with the required iodine.

The direct relation between high blood cholesterol and cardiovascular diseases has been proved. Food containing high amount of cholesterol such as meat and meat products, egg yolk, milk and dairy products can be elevated the cholesterol content in blood plasma. The possibility of cholesterol reduction in milk using beta cyclodextrin was investigated. In this research, various amounts of β- cyclodextrin (0, 0.5, 1 and 1.5 %) were mixed with Raw (unhomogenized and unpasteurized) and homogenized milk at two temperature conditions of 8oC and 20oC. The cholesterol content of milk was measured for each treatment. The results that statistically were analyzed and showed that the cholesterol content of milk remarkably was decreased with increasing the amount of β- cyclodextrin, particularly in homogenized milk at 20oC.However, the reduction rate of cholesterol were decreased when extra b- cyclodextrin added due to its intermolecular reactions. The maximum cholesterol reduction was achieved when 1.5 % b -cyclodextrin added to homogenized milk at 20oC.