Overview
SIST EN ISO 29981:2026 specifies a standardized method for the selective enumeration of bifidobacteria in milk products using a colony-count technique. Developed by CEN and aligned with ISO 29981:2024, this standard provides a reliable laboratory protocol for accurately quantifying viable bifidobacteria at 37 °C under anaerobic conditions. Its targeted application spans fermented milks (such as yogurt), non-fermented milks (pasteurized, skim, whey), milk powders, infant formulae, and probiotic or starter cultures. The ability to measure the presence of bifidobacteria is essential for quality assurance, regulatory compliance, and product labeling in the dairy and food industries.
Key Topics
- Colony-count Technique: Specifies procedures for culturing, isolating, and counting bifidobacteria colonies using selective media (e.g., TOS-MUP agar).
- Sample Preparation: Detailed steps for preparing test samples from a variety of dairy matrices, following aseptic and standardized conditions to ensure accuracy.
- Anaerobic Incubation: Enumeration is conducted at 37 °C in an anaerobic environment, supporting optimal bifidobacterial growth.
- Species Coverage: Designed for typical bifidobacteria used in dairy products, such as:
- Bifidobacterium adolescentis
- B. animalis subsp. animalis
- B. animalis subsp. lactis
- B. bifidum
- B. breve
- B. longum subsp. infantis
- B. longum subsp. longum
- Applicable Products: Includes fermented dairy (yoghurt), non-fermented milks, milk powders, infant and follow-up formulae, and products for young children.
Applications
SIST EN ISO 29981:2026 is widely applicable in dairy microbiology laboratories, quality control departments, and R&D environments across the milk products sector. Key uses include:
- Regulatory Compliance: Ensures dairy and formula products meet local and international microbiological criteria for bifidobacteria content.
- Product Labeling and Claims: Supports substantiation of “live cultures” and probiotic claims through accurate, standardized enumeration.
- Quality Assurance: Enables routine testing of finished products and in-process samples to monitor product consistency and shelf-life.
- Starter and Probiotic Cultures: Assesses the viability of bifidobacteria strains used as starter cultures or as probiotics in functional foods.
- Infant Nutrition: Validates bifidobacteria presence in infant and follow-up formulae, supporting the health and safety of products for sensitive populations.
By adopting this standard, organizations can demonstrate due diligence in delivering high-quality milk products with reliable bifidobacteria counts, improving consumer confidence and market access.
Related Standards
Organizations implementing SIST EN ISO 29981:2026 should also consider the following related international standards for best practices in dairy microbiological analysis:
- ISO 6887-1: Preparation of test samples, initial suspension, and decimal dilutions for microbiological examination - General rules.
- ISO 6887-5: Specific rules for the preparation of milk and milk products.
- ISO 7218: General requirements and guidance for microbiological examinations of the food chain.
- ISO 11133: Preparation and performance testing of culture media.
- ISO 19036: Estimation of measurement uncertainty for quantitative determinations.
- CXS 243-2003: Proposed quality criteria for dairy products (Codex Alimentarius).
Utilizing SIST EN ISO 29981:2026 alongside these standards strengthens laboratory competence and ensures harmonized, reproducible results across the dairy industry.
Keywords: SIST EN ISO 29981:2026, enumeration of bifidobacteria, colony-count technique, dairy microbiology, milk products, probiotic cultures, infant formula, quality assurance, anaerobic conditions, standardized method, milk powders.
