INLAIN   20354
INSTITUTO DE LACTOLOGIA INDUSTRIAL
Unidad Ejecutora - UE
artículos
Título:
Production of peptides and free amino acids in a sterile extract describes peptidolysis in hard-cooked cheeses
Autor/es:
MILESI, MARÍA M.; BERGAMINI, CARINA V.; HYNES, ERICA R.
Revista:
FOOD RESEARCH INTERNATIONAL
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2011 vol. 44 p. 765 - 765
ISSN:
0963-9969
Resumen:
Hard cooked cheeses are mostly manufactured with lactic starters of Lactobacillus helveticus, which constitute a major proteolytic agent in the food. In this work, we assessed the proteolysis produced by enzymes of two strains of L. helveticus in a new cheese model, which consisted of a sterile substrate prepared with hardcooked cheeses, and identified the time of ripening when main changes in proteolysis are produced. The extract, a representative model of the aqueous phase of the cheeses, was obtained from Reggianito cheeses of different ripening times (3, 90, and 180 days) made with starters composed of the strains tested, either SF138 or SF209. To obtain the substrate, the cheese was extracted with water, then centrifuged and the aqueous phase was sterilized by filtration through membrane (0.45 ìm). The substrates were incubated at 34 °C during 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with extract, a representative model of the aqueous phase of the cheeses, was obtained from Reggianito cheeses of different ripening times (3, 90, and 180 days) made with starters composed of the strains tested, either SF138 or SF209. To obtain the substrate, the cheese was extracted with water, then centrifuged and the aqueous phase was sterilized by filtration through membrane (0.45 ìm). The substrates were incubated at 34 °C during 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with extract, a representative model of the aqueous phase of the cheeses, was obtained from Reggianito cheeses of different ripening times (3, 90, and 180 days) made with starters composed of the strains tested, either SF138 or SF209. To obtain the substrate, the cheese was extracted with water, then centrifuged and the aqueous phase was sterilized by filtration through membrane (0.45 ìm). The substrates were incubated at 34 °C during 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheeses, and identified the time of ripening when main changes in proteolysis are produced. The extract, a representative model of the aqueous phase of the cheeses, was obtained from Reggianito cheeses of different ripening times (3, 90, and 180 days) made with starters composed of the strains tested, either SF138 or SF209. To obtain the substrate, the cheese was extracted with water, then centrifuged and the aqueous phase was sterilized by filtration through membrane (0.45 ìm). The substrates were incubated at 34 °C during 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with extract, a representative model of the aqueous phase of the cheeses, was obtained from Reggianito cheeses of different ripening times (3, 90, and 180 days) made with starters composed of the strains tested, either SF138 or SF209. To obtain the substrate, the cheese was extracted with water, then centrifuged and the aqueous phase was sterilized by filtration through membrane (0.45 ìm). The substrates were incubated at 34 °C during 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble peptides and free amino acids. Great variation in peptide profiles was found as incubation progressed in cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with cheese extracts, which evidenced that proteases and peptidases from the starter were active and able to degrade the proteinaceous material available in the extracts. The extracts derived from cheeses with extract, a representative model of the aqueous phase of the cheeses, was obtained from Reggianito cheeses of different ripening times (3, 90, and 180 days) made with starters composed of the strains tested, either SF138 or SF209. To obtain the substrate, the cheese was extracted with water, then centrifuged and the aqueous phase was sterilized by filtration through membrane (0.45 ìm). The substrates were incubated at 34 °C during 21 days; samples were taken at 0, 3, 7, 14, and 21 days. Sterility was verified by plating samples on skim milk agar and incubating at 37 °C for 48 h. Proteolysis was determined by liquid chromatography of soluble