Effect of Buttermilk Made from Creams with Different Heat Treatment Histories on Properties of Rennet Gels and Model Cheeses

Schematic representation of ingredient manufacture.

Sodium dodecyl sulfate-PAGE (12.0% acrylamide) profile of (I) initial buttermilk, (P) pH 4.6 precipitate, and (S) pH 4.6 supernatant. Initial buttermilks and supernatant were diluted 1:10 and 1:2, respectively, with sample buffer. Precipitates were dissolved (50mg/mL) in sample buffer. MW = molecular weight (kDa); WM = whole milk; MFGM = milk fat globule membrane.

Scanning electron micrographs (1,000×) of rennet gel made from milk standardized with (a) raw skim milk, (b) pasteurized skim milk, (c) skim milk from whole milk pasteurized before skimming, (d) raw cream buttermilk, (e) pasteurized cream buttermilk, and (f) buttermilk from cream separated from pasteurized whole milk. Bars are 50μm.

Sodium dodecyl sulfate-PAGE (15.0% acrylamide) profile of whey from cheese milk standardized with (lane 1) raw skim milk, (lane 2) pasteurized skim milk, (lane 3) skim milk from milk pasteurized before separation, (lane 4) raw cream buttermilk, (lane 5) pasteurized cream buttermilk, and (lane 6) buttermilk from cream separated from pasteurized whole milk. Whey was diluted 1:3 with sample buffer. MW = molecular weight (kDa); MFGM = milk fat globule membrane protein.