We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Technical note: development of a quantitative PCR method for monitoring strain dynamics during yogurt manufacture.
- Authors
Miller, D M; Dudley, E G; Roberts, R F
- Abstract
Yogurt starter cultures may consist of multiple strains of Lactobacillus delbrueckii ssp. bulgaricus (LB) and Streptococcus thermophilus (ST). Conventional plating methods for monitoring LB and ST levels during yogurt manufacture do not allow for quantification of individual strains. The objective of the present work was to develop a quantitative PCR method for quantification of individual strains in a commercial yogurt starter culture. Strain-specific primers were designed for 2 ST strains (ST DGCC7796 and ST DGCC7710), 1 LB strain (DGCC4078), and 1 Lactobacillus delbrueckii ssp. lactis strain (LL; DGCC4550). Primers for the individual ST and LB strains were designed to target unique DNA sequences in clustered regularly interspersed short palindromic repeats. Primers for LL were designed to target a putative mannitol-specific IIbC component of the phosphotransferase system. Following evaluation of primer specificity, standard curves relating cell number to cycle threshold were prepared for each strain individually and in combination in yogurt mix, and no significant differences in the slopes were observed. Strain balance data was collected for yogurt prepared at 41 and 43°C to demonstrate the potential application of this method.
- Publication
Journal of dairy science, 2012, Vol 95, Issue 9, p4868
- ISSN
1525-3198
- Publication type
Journal Article
- DOI
10.3168/jds.2012-5445