Análise de componentes principais na orientação de assistência técnica para produtores de leite cru refrigerado

Abstract

The improvement of the quality of milk and its derivatives in Brazil has grown due to the nutritional and sanitary requirements of dairy and consumers. It was evaluated the orientation of the technical assistance actions for the improvement of milk quality through principal components analysis. It was used data of quantity and quality of milk collected from January 2014 to July 2017, from 78 dairy farms located in the north of Minas Gerais. The analyzed variables were volume produced of milk, fat content, protein, lactose, dry extract defatted, somatic cell count, total bacterial count and milk temperature. Descriptive statistics and Pearson correlation among the characteristics were estimated. In addition, multivariate analyzes were performed using the principal components methodology, with the aid of the statistical program R. The data were grouped according to the climatic conditions in dry and rainy season. The first three main components, both periods, were responsible for explaining 69.71% and 67.81% of the total variation of the data set, in the rainy and dry period, respectively. Producer 18 presented the best nutritional and hygienic quality of the milk both in the dry period and in the rainy season. Producers 50 and 70 stood out negatively with regard to quality in both periods. The results show that the main component analysis is effective to simplify the data set, allowing a simple and quick interpretation by technical professionals. This may facilitate the proposal of assistance strategies for producers of refrigerated raw milk.