با همکاری انجمن علوم و صنایع غذایی ایران

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشگاه فردوسی مشهد

2 گروه علوم و صنایع غذایی، دانشکده کشاورزی، دانشگاه فردوسی مشهد، مشهد، ایران.

3 دانشگاه آریزونا

چکیده

در این مطالعه کیفیت میکروبی سبزیجات خام پس از برداشت در شهر مشهد مورد بررسی قرار گرفت و میزان فراوانی میکروبهای شاخص و بیماریزای روده ای در این منطقه تحقیق شد. در این پژوهش 98 نمونه سبزی خام در طی یک دوره 7 ماهه از اواسط بهار تا اواسط پاییز آزمایش شد. نتایج نشان داد که سطوح فراوانی باکتریهای مزوفیل هوازی بر روی 83 درصد سبزیجات خام کمتر از cfu/g 107 بود و 100 درصد سبزیجات به انتروباکتریاسه و باکتریهای کلی فرمی آلوده بودند و میانگین آنها از 1 تا 2/6 سیکل لگاریتمی متغیر بود. میانگین باکتریهای خانواده اسید لاکتیک و کپک ومخمر به ترتیب عبارت بود از 1/4 و 5/4 سیکل لگاریتمی و میزان فراوانی کپک ومخمر در 83 درصد سبزیجات خام کمتر از 5 سیکل لگاریتمی بود. 7/12 درصد سبزیجات خام به اشرشیا کلی آلوده بودند اما فقط 1/4 درصد نمونه ها میزان آلودگیشان بیشتر از 2 سیکل لگاریتمی بود. سطوح فراوانی اشرشیا کلی O157:H7 و سالمونلا بر روی سبزیجات خام به ترتیب 4 و 7/12 درصد بود. 9/94 درصد نمونه ها به استافیلوکوکوس اورئوس آلوده بودند که 8/7 درصد آنها کواگولاز مثبت بودند.

کلیدواژه‌ها

عنوان مقاله [English]

Incidence Levels of Enteric Pathogens and Microbial Quality of Raw Vegetables in Mashhad, Iran

نویسندگان [English]

  • Masoumeh Bahreini 1
  • Mohammad Bagher Habibi Najafi 2
  • Mohammad Reza Bassami 2
  • Morteza Abbaszadegan 3

1 Ferdowsi University of Mashhad

2 Department of Food Science and Technology, Ferdowsi University of Mashhad, Mashhad, Iran.

3 Department of FoodMicrobiology, Arizona State University

چکیده [English]

We investigated the microbiological quality of raw vegetables in Mashhad, Iran. In order to document the incidence of indicator and pathogenic microorganisms in this area. ninety eghit raw vegetable samples collected during 7 months were analyzed. All samples were examined for the presence of aerobic mesophilic bacteria, coliforms, Enterobacteriaceae, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus, yeast and mould. Our data showed that the incidence levels of aerobic mesophilic bacteria was less than 107 cfu/g on 83% raw vegetables and 100% of raw vegetables were contained Entrobacteriace and total coliforms, and their range varied from 1 log to 6 log cfu/g. The mean counts of Lactic acid bacteria and yeasts and moulds were 4.1 log cfu/g and 4.5 log cfu/g, respectively, and the incidence levels of yeasts and moulds in 83% of raw vegetables was less than 5 log cfu/g. Our results were similar with other studies that determined microbial levels on raw vegetables. 12.7% of samples raw vegetables contained E.coli, but only 4.1% were higher than ≥ 2 log cfu/g. The incidence levels for E.coli O157:H7 and Salmonella on raw vegetables were 6% and 12.7% respectively. 94.9% of raw vegetables were contaminated with S. aureus and 7.8% of them were coagulase positive.

کلیدواژه‌ها [English]

  • Raw vegetables
  • Enteric pathogenic bacteria
  • Microbial quality
  • Incidence level
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