Gelation Profiles of Yogurt as Affected by Heat Treatment of Milk

Abstract

Milk was heated at 140C for 6 s (UHT), 98C for 1.87 min (HTST) and 85C for 10 min (vat-pasteurized), homogenized, inoculated with yogurt culture, and incubated at 45C. During incubation, pH, ionic Ca, and viscosity changes were continuously monitored by interfacing to a microcomputer. Samples for transmission electron microscopy were taken at selected pH intervals.