Microbiological and Chemical Characterization of Halvi, a Traditional Iranian Dairy Product Made from Sheep Milk

Halvi is a traditional dairy product made from sheep milk in Mazandaran province, especially in the mountainous areas of Noor and Kojur. The fungus used in the preparation of Halvi is Auricularia auricula-judae. The present study aimed to investigate the chemical composition and microbiological properties of Halvi samples produced in various regions in Noor city, Iran.  In total, 42 Halvi samples were collected from various regions in Noor, including Chamestan (n=30), central Noor (n=8), and Baladeh (n=4), for the evaluation the chemical (protein, fat content, dry matter, ash, and pH) and microbiological analysis (aerobic plate count, coliform, molds and yeasts, Staphylococcus aureus, and Escherichia coli).  The microbiological results indicated that the samples collected from Chamestan had the highest count of aerobic mesophilic bacteria (6.4 log CFU/g). On the other hand, the samples collected from Chamestan and central Noor were more contaminated with coliform bacteria and yeast and mold compared to the samples collected from Baladeh. Moreover, S. aureus and E. coli were detected in 66.16% and 5.9% of the samples, respectively. The mean pH and protein, fat, ash, and dry matter content of the samples was 6.71, 6.84%, 8.87%, 1.42%, and 21.67%, respectively.  According to the results, contamination with the mentioned pathogens indicates stricter control and proper measures during the preparation of Halvi.