Harmony in Dairy Craftsmanship: A Symphony of Standards in Fermented Milk Production

Orchestrating Excellence in Fermented Milk Production through Rigorous Standards and Craftsmanship
January 12, 2024 by
Desiree Okpiaifo

In the intricate world of dairy craftsmanship, the creation of fermented milk products is a delicate dance of microorganisms. Guided by the stringent standards of ISO 27205:2010, this journey encompasses the preparation of starter cultures, focusing primarily on lactic acid bacteria. Noteworthy inclusions are propionobacteria and bifidobacteria, sculpting the foundation of the delectable offerings in the dairy aisle.

Probiotic Properties Disclaimer: It's essential to clarify that bacteria known for their probiotic properties do not grace the stage in this particular performance. 

Enumeration of Lactic Acid Bacteria in Starter Cultures:

1. Lactobacillus delbrueckii subsp. bulgaricus:
- Method: MRS Broth method (ISO 7889).
2. Lactobacillus acidophilus:
- Method: MRS Agar method with clindamycin and ciprofloxacin (ISO 20128).
3. Enterococcus faecium, pediococci, and lactobacilli:
- Method: MRS Agar following ISO 7889, incubated for 72h at 37ºC with a pH of 6 - 6.4.
4. Lactococci and Streptocuccus thermophilus:
-Method: M17 Agar 1318 (ISO 7889), with specific pH conditions for Lactococci and S. thermophilus.
5. Citrate-fermenting lactic acid bacteria:
- Method: Nickels and Leesment method (ISO 17792).
6. Leuconostoc spp.:
- Method: Nickels and Leesment with vancomycin method (ISO 17792).

Enumeration of Propionobacterium spp. in Starter Cultures:

- Method: Modified yeast extract-lactate medium

Enumeration of Bifidobacterium spp. in Starter Cultures:

- Method: TOS Agar 2011 medium containing Mupirocin 6074.

Detection and Enumeration of Contaminants:

1. Non-acid lactic bacteria: ISO 13559.
2. Yeast and moulds: OSP 6611, ISO 21257.
3. Enterobacteriaceae: ISO 21528.
4. Coagulase-positive Staphylococci: ISO 6888.
5. Listeria monocytogenes: ISO 11290.
6. Salmonella spp.: ISO 6785, with specific modifications for different CFU levels.

Specific Rules for Milk and Milk Products Preparation (ISO 6887-5:2017)


Aiming for safe dairy products requires rigorous testing of raw milk at various stages of transportation.


1. Follow ISO 6887-1 for frozen products.
2. For dry products, mix with a diluent, being cautious of temperature.
3. Homogenize heterogeneous products.

General Approach:

1. Neutralize pH for acid products.
2. Dilute food products with high fat content to improve emulsion during suspension.

Specific Procedures:

1. Milk and liquid milk products: Mix 25 times and dilute 1:10 with Saline Peptone Water.
2. Milk powder, cheese, butter, ice cream, and more: Specific procedures for each product category.

In this symphony of precision, dairy producers weave quality into each batch, ensuring the delightful outcome on your table. The adherence to these standards not only guarantees a palatable experience but also underscores the commitment to food safety and excellence in the dairy industry. 

Condalab 1318 | M17 Agar 500grams 

Condalab 2011 | TOS Propionate Agar Base ISO 500grams

Condalab 6074 | Selective Supplement MUP 10 Vials

REST Client (Huachao Mao)