Document Type : Original Article

Abstract

The present study compared the chemical, physical and sensory properties of textured skim milk with skim and whole milk over 1, 3, and 5 days of storage at 4±1 °C. A skim milk sample was heated at 60°C for 15 min, then 0.4 ml of rennet solution were added to 100 ml of the milk. The milk and rennet mixture was then pasteurized at 65°C for 30 min to deactivate the rennet. Skim, whole and textured milk samples were tested for pH, titratable acidity, protein, fat and total solids and colorimetrics, viscosity, appearance, structure, texture, taste, flavor and overall parameters on days 1, 3 and 5 of storage in a refrigerator. The results revealed that values for the chemical properties of the textured skim milk fell between those of the skim and whole milk for all storage times. The textured skim milk also showed greater viscosity, higher whiteness, yellowness and greenness values than did skim milk (p>0.05). Panelists scored textured skim milk higher than skim milk and nearly identically to whole milk. Overall, textured milk was found to have properties similar to whole milk and remains stable over 5 days of storage. For industrial purposes, this product can be simply produced by limiting rennet activity.

Keywords

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