EFFECT OF PARA-AMINOBENZOIC ACID MILK SUPPLEMENTING ON THE AMINO ACID PROFILE OF SEMI-HARD CHEESE

Abstract

The objective of this work is to analyze the cheese amino acid profile through the ripening period. The evaluation of the effect of Para-aminobenzoic acid (PABA) on the proteolytic activity of Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, and Streptococcus salivarius subsp. thermophilus, allows to deduce their vitality during the ripening period within 28 days. Four cheeses have been prepared and analyzed (a) control cheese, (b) cheese with 0.1 g/l PABA, (c) cheese with 0.2 g/l PABA and (d) cheese with 0.4 g/l PABA – in two stages: t0 (beginning of ripening period) and t1 (end of ripening period). The protein content was measured by Kjeldahl method and the amino acid profile was done by High-Performance Liquid Chromatography (HPLC). In the cheeses with 0.1 and 0.2 g/liter (PABA), significantly higher contents of most amino acids were measured compared to those for the control cheese. In the cheese samples with 0.4 g/liter PABA all amino acids were significantly higher in quantity than those in the control cheese.