el-Samragy Y A, Hansen C L, McMahon D J
Utah State University, Department of Nutrition and Food Sciences, Logan 84322-8700.
J Dairy Sci. 1993 Feb;76(2):388-92. doi: 10.3168/jds.S0022-0302(93)77357-9.
Raw skim milk retentate with 20% solids produced by UF was subjected to different heat treatments and pH adjustments prior to spray-drying. The heat treatments were 65 degrees C for 30 min, 75 degrees C for 28 s, and 85 degrees C for 28 s. pH was adjusted to 6.4, 6.7, and 7.0. Retentate powders were analyzed for moisture, protein, lactose, fat, ash, titratable acidity, and pH. Physical property determinations included solubility index, dispersibility, viscosity, scorched particles, poured density, packed density, and water absorption isotherm. No interaction effects of heat treatment and pH adjustment were observed. pH adjustments affected ash content and solution viscosity. Heat treatment affected solubility and poured density. pH adjustments and heat treatment had only minor effects on the measured properties.
通过超滤生产的含20%固体成分的脱脂乳浓缩物在喷雾干燥前进行了不同的热处理和pH值调节。热处理条件为65℃保持30分钟、75℃保持28秒和85℃保持28秒。pH值调节至6.4、6.7和7.0。对浓缩物粉末进行了水分、蛋白质、乳糖、脂肪、灰分、可滴定酸度和pH值分析。物理性质测定包括溶解度指数、分散性、粘度、焦粒、松装密度、堆积密度和吸水等温线。未观察到热处理和pH值调节的相互作用影响。pH值调节影响灰分含量和溶液粘度。热处理影响溶解度和松装密度。pH值调节和热处理对所测性质仅有微小影响。
