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Showing 6 results for Raw Milk
Occurrence of Bacillus cereus in raw milk receiving from UF-Feta Cheese Plants
Zhila Moradi-Khatoonabadi, Yahya Maghsoudlou, Hamid Ezzatpanah, Morteza Khomeiri, Mehdi Aminafshar,
Volume 6, Issue 4 (3-2014)
Abstract
Background and Objective: Milk and milk products are very suitable medium for growing microorganisms (e.g. Bacillus cereus). B. cereus is spore former bacilli, which easily survives during pasteurization and makes several problems in dairy industries. The aim of this study was to investigate aerobic spore and B. cereus of receiving raw milk from three UF plants. Materials and Methods: Samples were gathered from raw milk transport tankers arrived to plants during 30 days in winter. Also, the swab test was used for detection of B.cereus residual on milk contact surfaces. Results: High contamination level of aerobic spores (AeSC) and especially B.cereus were found in most samples compared with the criteria established by national and international standards. Although total viable count (TVC) in samples from industrial farms (IF) was lower than those from traditional farms (TFs) and milk collection centers (MCCs), considerable AeSC and B.cereus were transmitted to the UF plants from IFs. The highest and lowest TVC and B.cereus were found in samples from IFs and MCCs, respectively. In addition, our investigation in IFs revealed that teats contamination to soil and feces, as well as contaminated bedding might were the most important sources of B. cereus and AeSC of raw milk. Moreover, the results of swab tests confirmed that the “cleaning in place” system may not remove B.cereus effectively. Conclusion: It seems that for classifying raw milk quality, AeSC might be used as a more effective quality factor than TVC. Management commitment is effective to improve quality by balance between the amount and quality of receiving raw milk. This leads to the lower contamination in dairy plants and final products.
Assessment of Prevalence and Antibiotic Resistance of Staphylococcus aureus in Raw and Pasteurized Milks of Sari City in the Summer of 2014
Mh Dehghani, B Akbarpour, M Salari, A Poursheykhani, H Rasoulzadeh,
Volume 9, Issue 2 (9-2016)
Abstract

Background and Objectives: Milk is a full meal that can provide an appropriate growing environment for different bacteria. Hence, it can be hazardous to human health in unpasteurized conditions. The present study was conducted in order to assess the prevalence and antimicrobial resistance of Staphylococcus aureus in raw and pasteurized milks of Sari City in the summer of 2014.

Materials and Methods: This cross-sectional study was conducted in the summer of 2014 in the city of Sari. Totally, 160 samples- each 200 mL of raw milk were collected from collection and distribution centers (80 samples) of raw milk, and pasteurized milk from food stores (80 samples). Under aseptic conditions, confirmatory tests were carried out in Chapman and Blood agar media. Antibiogram test was performed for positive samples. Results were analyzed using SPSS (Ver. 19) software through the t-test descriptive statistical analysis.

Results: The results showed that 38.75% of 80 samples of raw milk collected were contaminated by Staphylococcus aureus, while no contamination was observed in pasteurized milk samples. The average number of colony formation of raw milk was estimated to be within 3×104 to 7×104 Cfu/mL. Maximum sensitivity was found against vancomycin, gentamicin, and Co-trimoxazole antibiotics and the maximum resistance was observed  against ampicillin, methicillin and cephalotin antibiotics with of 87.5, 25, and 12.5%, respectively.

Conclusion: The raw milk showed the prevalence of Staphylococcus aureus. Therefore, compliance with and control of sanitation at different steps of preparation, supplying and consumption of milk can prevent the human infection with this type of contamination.


Determination of organochlorine pesticide residues in the raw milk taken from milk collection centers in Urmia in 2020
Naiema Vakili Saatloo, Tooraj Mehdizadeh, Javad Aliakbarlu, Rahele Tahmasebi,
Volume 14, Issue 2 (9-2021)
Abstract
Background and Objective: Milk is one of the most important components of human food. In recent decades, the continued use of pesticides has led to contamination of soil, water, air and milk and caused public concern in the community. Long-term exposure to pesticide residuals in the food chain can be harmful. Therefore, there is a need to control environmental conditions in order to improve its healthy and sustainable food processing practices.
Materials and Methods: In this study, 30 samples of raw milk were randomly collected in October 2020, from milk collection centers in Urmia and the residual pesticides were determined using gas chromatography–mass spectrometry (GC-MS).
Results: Organochlorine pesticides were detected in some raw milk samples. The highest concentrations of Lindane (γ-HCH) were detected with the values ranging from 0.3 to 0.6 mg/kg in 5 milk samples. Atrazine was detected in 15 samples with the values ranging from 0.8 to 1.33 mg/kg and alachlor was found in 13 samples with the varied range of 0.35 to o.5 mg/kg. Organochlorine pesticide concentrations were higher than maximum residue level (MRL) in all contaminated milk samples according to the values mentioned by the European Union.
Conclusion: This study showed that atrazine, lindane and alachlor were higher than MRL according to European Commission (EC). However, other organochlorine pesticides such as Heptachlor, Aldrin and hexachlorocyclohexane (HCH) isomers (α, β and γ) were not detected.

Heavy metals in blood and milk of grazing animals around the vicinity of Zanjan zinc industrial park
Mohammad Hossein Nemati,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: Environmental pollution with heavy metals and consequently their entry into food chains leads to irreparable damage to human health. The aim of this study was to determine the concentration of heavy metals including copper, zinc, lead and cadmium in blood and milk of grazing livestock around Zinc industry in Zanjan province (VSIPZ).
Materials and Methods: A total of 10 samples of grazing blood and milk were taken in each of the four geographical directions of the desired location. Also, in order to compare the current situation in the study area with the non-polluted areas, the control area (Qarah Poshtlu area of Zanjan) was considered. Dry ash method was used to digest organic matter.
Results: The results showed that the concentration of copper in the blood of cows and sheeps and the concentration of lead in the blood of cows in the west of VSIPZ was higher than the control group (p <0.05). There was no significant difference between the study areas and the control in terms of zinc and cadmium concentration in blood samples. Copper concentrations in cows and sheeps milk were lower than the control group in the southern and eastern regions of the VSIPZ, respectively (p <0.05). Zinc and lead concentrations in sheeps’ milk were higher than the control in the south and west of the VSIPZ, respectively (p <0.05).
Conclusion: In general, the results implied that the accumulation of lead in sheeps’ milk in the west of VSIPZ is more than maximum allowable concentration and can endanger the health of consumers.

Investigating the amounts and risk assessment of lead in raw milk collected from farms in Tehran province in winter, 2022
Alireza Bakhtiyari, Behrouz Akbari-Adergani, Parisa Shavli-Gilani, Liela Karami, Najmeh Yazdanfar, Parisa Sadighara,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Given the crucial role of milk and its products in human diets, it is imperative to implement effective measures to ensure the safety of milk by minimizing the presence of hazardous pollutants. This study aims to assess the concentration and potential risks associated with lead in raw milk produced in Tehran province.
Materials and Methods: This cross-sectional descriptive study involved the collection of raw milk samples from 24 diverse livestock farms in Tehran province during the winter season of 1401. The samples were analyzed for lead contamination using flame atomic absorption spectrometry. Statistical tests were applied to compare the results with international standards, and subsequent risk assessment was conducted based on the average amounts.
Results: The study revealed that none of the samples exceeded the permissible limit for lead. The mean and standard deviation of lead concentration in the samples was 7 ± 5.8 (ppb), well below the international standard. There was no significant variation in lead levels among the tested livestock farms. The Hazard Quotient (HQ) values for both children and adults were calculated to be less than 1.
Conclusion: The concentration of lead in all samples remained below the permissible limits set by Codex and the Iran Standards Organization, indicating no non-carcinogenic risks associated with milk consumption in terms of lead contamination, as suggested by the calculated HQ values.
 

Evaluation of antibiotic residues in raw milk of Fars province by rapid method in 2018 and determining the amount of oxytetracycline, enrofloxacin and penicillin G in contaminated samples
Majid Hashemi, Mohammad Javad Agah, Amir Mahmoud Rastegar,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Paying attention to antibiotic residues in milk is important due to its health effects on the occurrence of microbial resistance in consumers, as well as its harmful effects on the dairy industry. This study was carried out with the aim of determining the amount of oxytetracycline, enrofloxacin, and penicillin G in raw milk samples produced in Fars province, which were detected as contaminated during screening with a rapid kit.
Materials and Methods: The samples were first examined with a rapid commercial kit for the presence of antibiotic residues. Then the amount of oxytetracycline, enrofloxacin and penicillin G antibiotics in the positive samples belonging to the middle month of each season was determined using the liquid chromatography-tandem mass spectrometry method.
Results: Antibiotic residues were found in 121 (7.7%) samples by the commercial Eclipse kit. Both season (p<0.001) and region (p<0.01) of sampling had a significant effect on antibiotic residues in raw milk. In the chromatographic method, antibiotic residues of oxytetracycline and enrofloxacin were detected in 6 (27.3%) samples, none of which exceeded the permissible limit determined by the Iranian Veterinary Organization.
Conclusion: Although the amount of antibiotics detected from raw milk from Fars province was much lower than the permissible limit, it is necessary to implement further executive, educational, and research measures to minimize these residues in raw milk due to the possibility of the presence of other antimicrobial substances.
 

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