Quality Assessment of Chemical and Microbiological Characteristics of Cow’s Milk and Some Dairy Products in the New Valley Governorate

Ismail, Hesham A; Mohamed, Amin G; Bakry, Amr M; Saad, Mariam Mohamed; Abouelnaga, Mohamed I

doi:10.21608/nvjas.2024.252399.1267

Quality Assessment of Chemical and Microbiological Characteristics of Cow’s Milk and Some Dairy Products in the New Valley Governorate

Document Type : Original Research

Authors

¹ Dairy Science, Department, Faculty of Agriculture, New Valley University, New Valley, Egypt

² Dairy Sciences, Department, Faculty of Agriculture, Suez Canal University, Egypt.

10.21608/nvjas.2024.252399.1267

Abstract

Raw cow’s milk, Kareish cheese, Domiati cheese and plain yoghurt were collected from four different areas in the New Valley Governorate for detecting chemical, microbiological properties. Cow’s milk was high in moisture (88.69%) & acidity (0.23%) and low in fat 2.41%, other components were normal. Total solids, salt and acidity in Kareish and Domiati cheeses were within the normal limits. Yoghurt was normal in TS% and low in fat than legal standards, while the acidity was quite high (0.95%) in most areas. Total bacterial counts were 6.56, 5.65, 3.70 and 6.25 log CFU.g^-1 for raw milk, Kareish cheese, Domiati cheese and yoghurt, respectively. Psychrotrphic bacterial counts were high in milk (4.20 log CFU.g^-1) and low in Domiati cheese (3.49 log CFU.g^-1). Lactic acid bacterial counts were high in raw milk & Kareish cheese (6.46 & 6.05 log CFU.g^-1) and low in Domiati cheese (2.45 log CFU.g^-1). Staphylococcus aureus was detected in Kareish cheese in El-Dakhla and Paris. It also detected in Domiati cheese in all regions except in Paris area and was found in yoghurt in El-Dakhla only. Coliform bacteria were detected in all samples; the highest count was in raw milk (3.64 log CFU.g^-1). Yeast and molds were detected in all samples and were high in Kareish and Domiati cheeses. Organoleptic properties revealed normal colour for all samples. Flavour and taste were to some extend accepted with salty taste in Domiati cheese and yeasty in Kareish cheese. Yoghurt was sour in taste; the overall quality was just accepted for all products.

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