ISO 19344:2015
Milk and milk products - Starter cultures, probiotics and fermented products - Quantification of lactic acid bacteria by flow cytometry

Standard No.

ISO 19344:2015

Release Date

2015

Published By

International Organization for Standardization (ISO)

Latest

ISO 19344:2015

Scope

This International Standard specifies a standardized method for the quantification of active and/or total lactic acid bacteria and probiotic strains in starter cultures used in dairy products by means of flow cytometry. The method is also applicable to probiotics used in dairy products and to fermented milk products such as yogurts containing primarily lactic acid bacteria. This International Standard does not apply to taxonomical differentiation of bacteria. Due to its nonspecificity, the method may quantify other bacteria than those within the scope of this International Standard, when present in the sample. This may lead to overestimation of the counts. The minimum bacterial cell concentration in the sample before applying this standardized method depends on the dilution rates used in the individual protocols. Typically 106 cells per gram or ml are considered within the minimum range.

ISO 19344:2015 Referenced Document

• ISO 15214:1998 Microbiology of food and animal feeding stuffs - Horizontal method for the enumeration of mesophilic lactic acid bacteria - Colony-count technique at 30 °C
• ISO 26323:2009 Milk products - Determination of the acidification activity of dairy cultures by continuous pH measurement (CpH)
• ISO 27205:2010 Fermented milk products - Bacterial starter cultures - Standard of identity
• ISO 5725-1:1994 Accuracy (trueness and precision) of measurement methods and results - Part 1: General principles and definitions
• ISO 5725-2:1994 Accuracy (trueness and precision) of measurement methods and results - Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method
• ISO 6887-1:1999 Microbiology of food and animal feeding stuffs - Preparation of test samples, initial suspension and decimal dilutions for microbiological examination - Part 1: General rules for the preparation of the initial suspension and decimal dilutions
• ISO 6887-5:2010 Microbiology of food and animal feeding stuffs - Preparation of test samples, initial suspension and decimal dilutions for microbiological examination - Part 5: Specific rules for the preparation of milk and milk products
• ISO 707:2008 Milk and milk products - Guidance on sampling
• ISO 7218:2007 Microbiology of food and animal feeding stuffs - General requirements and guidance for microbiological examinations
• ISO 7889:2003 Yogurt - Enumeration of characteristic microorganisms - Colony-count technique at 37 °C

ISO 19344:2015 history

• 2015 ISO 19344:2015 Milk and milk products - Starter cultures, probiotics and fermented products - Quantification of lactic acid bacteria by flow cytometry