ارزیابی آلودگی میکروبی و ویژگی‌های شیمیایی کشک‌های مایع سنتی عرضه‌شده در شهر همدان

نویسندگان
1 دانشجوی کارشناسی ارشد، گروه بهداشت و کنترل کیفی مواد غذایی، دانشگاه بوعلی سینا، همدان
2 دانشیار، گروه بهداشت و کنترل کیفی مواد غذایی، دانشگاه بوعلی سینا، همدان
3 دانشیار، گروه علوم و صنایع غذایی، دانشگاه بوعلی سینا، همدان
چکیده
هدف از این مطالعه بررسی انطباق یا عدم انطباق کشک‌های مایع سنتی عرضه‌شده در شهر همدان با استاندارد ملی ایران بود. برای انجام این پژوهش، نمونه‌های کشک از تولیدکنندگان محصولات لبنی سنتی (در شهر همدان) در طی دو مرحله تهیه و برای بررسی به آزمایشگاه کنترل کیفی مواد غذایی منتقل شدند. جمعیت میکروبی (شمارش کلی، استافیلوکوکوس، کلی‌فرم و کپک-مخمر)، ویژگی‌های شیمیایی (درصد ماده جامد، نمک، اسیدیته و pH) و پارامترهایی رنگی شامل روشنایی (L*)، قرمزی (a*) و زردی (b*) کشک‌های سنتی بررسی و بعد از آنالیز آماری نتایج آنها گزارش شد. متوسط تعداد میکروارگانیسم (شمارش کلی)، استافیلوکوکوس و کلی‌فرم در نمونه‌های کشک به ترتیب برابر Log cfu/g 28/7، Log cfu/g 09/4 و Log cfu/g 64/1 بود. بر اساس استاندارد ملی ایران، حداکثر تعداد کپک و مخمر کشک مایع باید Log cfu/g 2 باشد، اما متوسط تعداد کپک و مخمر در کشک‌های تهیه شده برابر Log cfu/g 39/7 بود که بسیار بیشتر از حد استاندارد مشخص شده برای این محصول است. میانگین درصد ماده جامد کشک‌ها 15/21 درصد بود که کمتر از حد استاندارد تعریف شده (حداقل 25 درصد) برای آن بود. همچنین میانگین رطوبت، نمک، اسیدیته و pH کشک‌های بررسی شده در این پژوهش به ترتیب 85/78 درصد، 98/1 درصد، 90/1 درصد و 09/4 بود. پارامترهای رنگی نمونه‌های کشک بررسی و میانگین شاخص‌های رنگی شامل روشنایی، قرمزی و زردی نمونه‌ها به ترتیب 52/84، 53/1 و 43/6 بود. البته از نظر آماری تفاوت معناداری بین مقادیر شاخص‌های رنگی نمونه‌ها مشاهده نشد (05/0<p).
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Evaluation of microbial contamination and chemical properties of traditional liquid Kashks supplied in Hamedan city

نویسندگان English

Samira Amin Ekhlas 1
Mohammad Reza Pajohi-Alamoti 2
Fakhreddin Salehi 3
1 MSc Student, Department of Food Hygiene and Quality Control, Bu-Ali Sina University, Hamedan, Iran.
2 Associate Professor, Department of Food Hygiene and Quality Control, Bu-Ali Sina University, Hamedan, Iran.
3 Associate Professor, Department of Food Science and Technology, Bu-Ali Sina University, Hamedan, Iran.
چکیده English

The purpose of this study was to investigate the conformity or non-conformity of traditional liquid Kashks supplied in Hamedan city with the national standard of Iran. To carry out this research, Kashk samples from manufactures of traditional dairy products (in Hamedan city) were prepared in two stages and transferred to the food quality control laboratory for examination. Microbial population (total count, staphylococcus, coliform, and mold-yeast), chemical properties (total solids %, salt, acidity, and pH) and color parameters including lightness (L*), redness (a*) and yellowness (b*) of tradition Kashk was examined and after statistical analysis, their results were reported. The average number of microorganisms (total count), staphylococcus and coliform in the Kashk samples were 7.28 Log cfu/g, 4.09 Log cfu/g, and 1.64 Log cfu/g, respectively. According to the national standard of Iran, the maximum number of mold and yeast in liquid Kashk should be 2 Log cfu/g, but the average number of mold and yeast in the prepared Kashks were 7.39 Log cfu/g, which is much higher than the specified standard for this product. The average of total solid of Kashks were 21.15%, which was less than the defined standard (at least 25%) for it. Also, the average of moisture, salt, acidity, and pH of examined Kashks in this research were 78.85%, 1.98%, 1.90%, and 4.09 respectively. Color parameters of Kashk samples were examined and the average color indexes including lightness, redness, and yellowness of the samples were 84.52, 1.53 and 6.43 respectively. Of course, no statistically significant difference was observed between the color indexes values of the samples (p>0.05).

کلیدواژه‌ها English

acidity
Coliform
Color Parameters
Mold and yeast
Staphylococcus
Total count
[1] Bagheri, M., Shaviklo, A. 2021. Microbiological safety, chemical and organoleptic properties of some nomadic dairy products of Chaharmahal and Bakhtiari province, Journal of Food Microbiology. 8, 50-63.
[2] Institute of Standards and Industrial Research of Iran. 2015. Liquid Kashk-Specifications and test methods. ISIRI no 2452, 1st Edition, Iran National Standards Organization (in Persian).
[3] Haji Mohamadi Farimani, R., Habibi Najafi , M. B., Fazli Bazaz , S. 2017. Chemical and microbiological characteristics of traditional yogurts produced by nomads in Khorasan-e-Razavi, Journal of Food Microbiology. 3, 29-38.
[4] Babaii, F., Hesari, J., Farajnia, S., Rafat, S. A., Fathi Achachiloyi, B. 2015. Effect of ultrasound waves and titanium dioxide on Staphylococcus aureus and Escherichia coli in liquid Kashk, Electronic Journal of Food Processing and Preservation. 7, 1-16.
[5] Kalantary, R., Mahdavi, S. 2017. Isolation and Molecular Identification of Salmonella spp. from Local Dairy Products in Maragheh City in 2015 (Iran), Qom University of Medical Sciences Journal. 11, 98-105.
[6] Hokmollahi, F., Ehsani, M. R. 2020. Characteristics of nodooshan goat milk and identification of volatile compounds in traditional nodooshan goat cheese during ripening, Iranian Journal of Nutrition Sciences and Food Technology. 14, 67-76.
[7] Azimi, Y., Esmaiili, M., Khosroshahi Asl, A. 2018. Investigation of physical, chemical, microbiological and sensory properties of Kashk dried by sun and hot air, Journal of Food Research. 28, 59-72.
[8] Mohamadi Sani, A., Nikpouyan, H., Moshiri Roodsari, R. 2010. Determining of heavy metals content in produced liquid and dry curdle in Khorasan-e- Razavi industries, Journal of Innovation in Food Science and Technology. 1, 17-22.
[9] Institute of Standards and Industrial Research of Iran. 2015. Milk, cream and evaporated milk - Determination of total solids content (Reference method). ISIRI no 11328, 1st Revision, Iran National Standards Organization (in Persian).
[10] Hosseini, Z.2006. Common Methods in Food Analysis, Shiraz University Pub,
[11] Institute of Standards and Industrial Research of Iran. 2006. Milk and milk products-Determination of titrable acidity and value pH-Test method. ISIRI no 2852, 1st Edition, Iran National Standards Organization (in Persian).
[12] Salehi, F. 2019. Color changes kinetics during deep fat frying of kohlrabi (Brassica oleracea var. gongylodes) slice, International Journal of Food Properties. 22, 511-519.
[13] Faraji, M., Farhoodi, M., Roozbeh Nasiraie, L. 2018. Antibacterial effect of ethanolic extract shallot (allium hirtifolium) on the clostridium botulinum & staphylococcus aureus and orgoanoleptic propertise of liquid curd, Iranian Journal of Nutrition Sciences and Food Technology. 12, 73-82.
[14] Institute of Standards and Industrial Research of Iran. 2017. Microbiology of milk and milk products-Specifications and test methods. ISIRI no 2406, 3st Edition, Iran National Standards Organization (in Persian).
[15] Salehi, F. 2018. Color changes kinetics during deep fat frying of carrot slice, Heat and Mass Transfer. 54, 3421-3426.
[16] Marvi, S., Mortazavi, S. A., Milani, E. 2018. Optimization of ultra-beneficial liquid curd formulation containing native inulin and guar, Journal of Innovation in Food Science and Technology. 10, 137-149.