Search In this Thesis
   Search In this Thesis  
العنوان
Risk assessment of some dairy products with special concern to safety issues /
المؤلف
Gadallah, Ahmed Hussein Abdallah.
هيئة الاعداد
باحث / أحمد حسين عبد الله جاد الله
مشرف / عبد الحي محمد أحمد أبوزيد
مشرف / كريمة مجاهد فهيم أحمد
الموضوع
Risk. Salmonella. Listeria.
تاريخ النشر
2020.
عدد الصفحات
135 p. ;
اللغة
الإنجليزية
الدرجة
ماجستير
التخصص
البيطري
تاريخ الإجازة
1/1/2020
مكان الإجازة
جامعة القاهرة - كلية الطب البيطري - Hygiene and Control of Milk and its Products
الفهرس
Only 14 pages are availabe for public view

from 148

from 148

Abstract

A total of 75 ice-cream samples and 75 white soft cheese samples (35 large scale and 40 small scale for each ice-cream and white soft cheese) were collected from street vendors, dairy shops and supermarkets in Cairo and Giza governorates. The collected samples were investigated for different types of hazards including, microbiological, chemical and physical. For microbiological examination; the mean count of total aerobic mesophilic bacteria, psychrotrophic bacteria, coliforms, fecal coliforms, yeast, mold and total staphylococci were 6.32 ± 5.8, 5.2 ± 4.5, 4.8 ± 4.4, 5.3 ± 4.7, 6.1 ± 5.8, 3.06 ±2.91, 5.13 ± 4.75, 2.55, 5.9 ± 5.6, 4.9 ± 4.5, 3.0 ± 2.6, 3.1 ± 2.9, 5.7 ± 5.2, 5.0 ± 4.5 for small and large scale ice-cream samples, respectively; and were 7.47 ± 6.98, 5.77 ±5.28, 6.70 ± 5.67, 5.33 ± 4.83, 7.71 ± 7.13, 3.43 ± 2.88, 6.30 ±5.99, 2.92 ± 2.53, 6.47 ± 5.71, 5.87 ± 5.39, 4.0 ± 3.89, 4.0 ± 3.93, 6.62 ± 5.08 ,5.5 ± 5.13 log cfu/g, for small and large scale white soft cheese samples, respectively. S. aureus was detected with incidence of 12.5%, 55.0%, 11.42% and 37.1% for small scale and large scale samples of ice-cream and cheese, respectively; while E. coli, salmonella, L. monocytogenes couldn’t be detected in all examined samples. For chemical hazards; aflatoxin M1 was examined using a commercial enzyme-linked immunosorbent assay (ELISA) and the obtained results revealed that 80% of the examined ice-cream and white soft cheese samples were contaminated with a mean value of 24.31 ± 8.11 and 14.19 ± 2.48 ppt, respectively. Some of the organochlorine pesticides (OCPs) and Polychlorinated biphenyls pesticides (PCBs) were examined using Gas chromatography (GC-MSMS); OCPs residues couldn’t be detected in all ice-cream samples, while α-HCH, β-HCH, γ-HCH, P,P-DDT, o,p-DDT, p,p-DDE and Aldrin were detected in the examined white soft cheese samples with mean values of 0.02 ± 01, 0.03 ± 01, 0.03 ± 01, 0.03 ± 0.01, 0.05 ± 0.02, 0.01, 0.08 ppm., respectively. All of the the examined samples of ice-cream and white soft cheese were free from Polychlorinated biphenyl (PCBs) residues. The collected samples were exposed to physical inspection for the detection of physical hazards; hair, plastic and metal pieces were detected in some small scale samples of ice-cream and white soft cheese. The assessment of the existed hazards and their public health impact as well as the methods to to safe guard human health from the adverse effects of these hazards were fully mentioned and discussed.