Determination of proteins and total carbohydrates in Whey Protein supplements

Abstract

In the recent years, the consumption of whey protein has increased in Brazil and in the world, due to the health concerns and the physical well-being. Currently, diverse brands and types of whey protein are commercially available. Several studies have shown irregularities in the chemical composition of analyzed samples, mainly in protein and total carbohydrate contents, when compared with those indicated in the labels. This study evaluated 15 samples of concentrated whey protein purchased in the Rio de Janeiro city. The total carbohydrate contents were determined by Lane Eynon, and the total nitrogen and protein by means of Kjeldahl. The used methodologies are official; and the analytical methods were previously validated. The results were compared with the values expressed in the respective products labels. For the total carbohydrate contents, of 15 evaluated samples only four complied with the labels. For protein contents, two samples did not meet the amounts stated on the label, considering the tolerance limit of ± 20 %, according to the ANVISA (Brazilian Agency for Health Surveillance). It is suggested to institute the specific standards for this type of product, for establishing better supervision and quality assurance, which will be profitable to the consumers.