title: Fermentation of reconstituted skim milk supplemented with soy protein isolate by probiotic organisms.
abstract: Utilization of lactose and production of organic acid were determined in reconstituted skim milk (RSM) and RSM supplemented with soy protein isolate (SPI) (RSMS) by 6 probiotic organisms, including L. acidophilus 4461, L. acidophilus 4962, L. casei 290, L. casei 2607, B. animalis subsp. lactis bb12, and B. longum 20099. The viable counts of probiotic organisms of RSM and RSMS were enumerated and pH measured during fermentation. Our results showed that 3% to 10% more lactose was utilized by all the 6 probiotic microorganisms from RSMS than RSM. All 6 probiotic organisms produced significantly more acetic acid in RSMS than RSM. However, the viable microbial populations in RSMS were lower than those in RSM due to lower pH of the former. It appears that addition of SPI enhanced lactose utilization and acetic acid production but slightly reduced the lactic acid production and the growth of probiotic microorganisms.
authors.affiliation: School of Molecular Sciences, Victoria Univ., Werribee Campus, P.O. Box 14428, Melbourne, Victoria 8001, Australia.
authors.forename: T T
authors.initials: TT
authors.lastname: Pham
authors.forename: N P
authors.initials: NP
authors.lastname: Shah
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D000818:Animals; D001407:Bacillus / Q000254:growth & development / Q000378:metabolism*; D015169:Colony Count, Microbial; D005285:Fermentation; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism; D007778:Lactobacillus / Q000254:growth & development / Q000378:metabolism*; D007785:Lactose / Q000378:metabolism*; D050296:Microbial Viability; D008892:Milk / Q000382:microbiology*; D019936:Probiotics; D030262:Soybean Proteins / Q000378:metabolism*
chemical_list: D030262:Soybean Proteins; D019344:Lactic Acid; D007785:Lactose; D019342:Acetic Acid