Qualidade físico química e microbiológica do leite em diferentes épocas do ano

Abstract

The goal of the experiment was to measure and assess the effects of lack of adequate cooling in obtaining and transporting the raw milk to dairy until his arrival by physical chemical and microbiological tests on hand milking and without milk coolers. The experiment was performed with milk coming from a single produceralso designed to evaluate the influence of the time of the year. For the tests were used 40 crossbred females, healthy lactating in a randomized block designand treatments were assembled in minutes elapsed to perform the analysis of quality of milk from milking until the end of the course of 150 minutes, being 30 minutes T1 after milking, 60 minutes T2 after milking, 90 minutes T3 after milking, 120 minutes T4 after milking and 150 minutes T5 after milking, during five days in the winter and five days in the spring. The days are repetitions of the treatment groups in minutes elapsed analyzed within each period (winter and spring). We measured pH tests, titratable acidity, density, freezing point, fat, total count of aerobic mesophilic, total solids and solids not. For the period of 30 minutes after milking, the difference was p<0.05 for the parameters acidity, fat, total solids and solids not fat, that result is repeated in periods of 60 and 90 minutes after milking, in periods of 120 and 150 minutes after milking the difference was p<0.05 for the parameters acidity, fat, aerobic mesophilic count, total solids and solids not fat. The milk collected at both stations during milking after 30 and 60 minutes is shown in better physical-chemical and microbiological, showing that the environmental factor was decisive for such results. The results of the analysis were submitted to Student's t test at a significance level of 5%, using statistical parametric Sisvar software version 5.1.