Amounts, Variations, and Interrelations of the Major Milk Components in Individual Farm Deliveries

Abstract

Summary Raw milk from 607 farms was analyzed during summer and again during winter for per cent milk fat (fat), total solids (TS), and total protein (TP). Fat was by Babcock; TS in a forced-air oven; and TP by alkaline steam distillation. Per cent solids-not-fat (SNF) and lactose-mineral (LM) were by difference. The averages and standard deviations for fat, SNF, TP, and LM, respectively, were: 3.89±0.45, 8.67±0.31, 3.29±0.23, and 5.38±0.22. The TS, fat, TP, and SNF averaged, respectively, 0.29, 0.22, 0.15, and 0.07% higher in winter, but the LM averaged 0.08% lower. The correlations were: between TS and fat, 0.93; SNF and fat, 0.60; LM and fat, 0.10; TP and fat, 0.74; and TP and SNF, 0.71. The interrelations of these components also were shown by regression coefficients and estimating equations.