title: Acceleration of yoghurt fermentation time by yeast extract and partial characterisation of the active components.
abstract: Water soluble autolysate of yeast, usually utilised for microbial growth support, was used as additive in yoghurt fermentation. The yeast extract (YE) resulted in a decrease of fermentation time by 21% to reach a pH of 4·6. However, the YE resulted in unacceptable flavour and taste. By size exclusion chromatography, a fraction of the YE was obtained that could account for the observed 21% decrease in fermentation time. The fraction contained molecules of low molecular weight, consisting of minerals, free amino acids and peptides. The acceleration of the yoghurt fermentation was ascribed to the short peptides in the fraction. It is proposed that the application of this extract in industrial yoghurt manufacture would result in savings for both the industry and the consumer.
authors.affiliation: Department of Microbial, Biochemical and Food Biotechnology, Faculty of Natural and Agricultural Science,University of the Free State,✉ 339 Bloemfontein, 9300,Republic of South Africa.
authors.forename: Esti-Andrine
authors.initials: EA
authors.lastname: Smith
authors.affiliation: Department of Microbial, Biochemical and Food Biotechnology, Faculty of Natural and Agricultural Science,University of the Free State,✉ 339 Bloemfontein, 9300,Republic of South Africa.
authors.forename: Jacobus
authors.initials: J
authors.lastname: Myburgh
authors.affiliation: Department of Microbial, Biochemical and Food Biotechnology, Faculty of Natural and Agricultural Science,University of the Free State,✉ 339 Bloemfontein, 9300,Republic of South Africa.
authors.forename: Gernot
authors.initials: G
authors.lastname: Osthoff
authors.affiliation: Department of Microbial, Biochemical and Food Biotechnology, Faculty of Natural and Agricultural Science,University of the Free State,✉ 339 Bloemfontein, 9300,Republic of South Africa.
authors.forename: Maryna
authors.initials: M
authors.lastname: de Wit
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D005285:Fermentation; D005511:Food Handling / Q000379:methods*; D008903:Minerals / Q000737:chemistry; D010455:Peptides / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism; D013997:Time Factors; D015014:Yogurt / Q000032:analysis* / Q000382:microbiology
chemical_list: D000596:Amino Acids; D008903:Minerals; D010455:Peptides; D029701:Saccharomyces cerevisiae Proteins