Studies on Hygienic Status of Kishk Product

Abstract

This study was carried out for monitoring the bacteriological and mycological quality of Kishk. Thirty six random samples of Kishk were collected from different farmer producer and shops in Assiut city and some villages around it. All samples were subjected to microbiological examinations and mycotoxine investigation. Enterococci spp., Aerobic bacteria, Anaerobic bacteria and "Yeasts and molds" were isolated in 61.6, 100, 86.1 and 77.8 % of the examined Kishk samples, respectively, and with average total counts of 6.95 x10 4 , 2.26 x 10 5 , --, and 3.9 x10 4 , respectively. The presence of high contamination in Kishk samples reflects the poor sanitary conditions during the manufacturing stages or post production. Aspergillus flavus, Aspergillus niger and Mucor spp. were detected in 22.2, 16.7 and 8.3 % of the examined Kishk samples, respectively. Aflatoxin M 1 was found in 23.53 % of the samples. The concentration of aflatoxin M 1 in positive samples was 139 -221 ng/Kg (average 149.8 ± 56.5 ng/Kg) by ELISA and 56 -218 ng/Kg (average 135.3 ± 61.5 ng/Kg) by TLC. Kishk samples from Assiut city presented a high incidence of AFM 1 at levels below the limits established by Egyptian regulations. The general human exposure to AFM 1 by the consumption of contaminated kishk is probably non-significant in Egypt. However, the fact that AFM 1 is a potent hepatocarcinogen warrants concern about its occurrence in kishk. A high percentage of positive samples would be considered inappropriate for human consumption, when considering the tolerance limit adopted by the European Community. It could be concluded that, the product quality is variable, with some samples showing noticeably more contamination than others. This is probably a reflection of the standards of hygienic measures applied during production and the quality of raw materials used (fermented milk and crushed dried boiled wheat grains).