Application and effect.
In the food industry, undesirable microorganism represents a certain danger - they limit shelf life of products and can represent a danger to health. Preservation have a bad reputation due t their negative effect on the human organism in case of high doses. Therefore, they are mostly not allowed for use in dairy products.
Danisco offers - under license of Valio – with Holdbac YM-B (BIO PROFIT) a protective culture of which the strains alone resp. in symbioses together inhibit undesired microorganisms in their growth and activity.
What does Holdbac YM-B contain?
Which groups of microorganisms are inhibited?
· Heterofermentative lactic acid bacteria,
· Coliform germs
· Spore-forming bacteria (bacilli, clostridia)
What is the effect of Holdbac YM-B?
The mode of effect is not completely investigated. The culture produces among others the organic acids lactic acid of the L (+) type, acetic and propionic acid. Furthermore, it produces other acids and small amounts of diacityl. The microbicide effects of the above mentioned substances are known.
In trials, however, were shown that the metabolic products separated from the culture by sterile filtration cause considerable lower inhibiting effects than combined with the culture, i.e. the cell substance together with the metabolic products causes the protective effect against yeast and moulds.
The inhibitation of microorganisms depends on strain and species. For instance, not all yeasts and moulds are inhibited.
Possibilities of application of Holdbac YM-B as protective culture - Trial results
Yogurt/Fermented milk products - Inhibition of growth of yeast's and moulds
Yogurt has been fermented in laboratory test with a starter culture of streptococcus thermophilus and Lactobacillus bulgaricus. 0.1 % of Holdbac YM-B (=cell count 107 / l yogurt milk) has been inoculated at the same time with the starter into the yogurt. Strawberry marmalade has been contaminated with Rhodotorula sp. Yeast.
Quark - Inhibition of growth of yeast's and moulds
Practical tests with:
1. Holdbac YM-B 0.01 %
2. Holdbac YM-B 0.1 %
3. Sorbic acid 0.06 %
4. Quark without additives as reference
Holdbac YM-B has been added too freshly fermented quark mass in an amount of 0.01 % and 0.1 %. The cell counts in quark ran up to 106 cfu/g and 107 cfu/g. Calcium sorbat has been suspended in water and added in doses so that die concentration in quark was at 0.06 %. The quark had been stored at + 6 0C for five weeks.
Inhibition of Rhodotorula sp. In quark by Holdbac YM-B and
Sorbic acid and without additives as reference
Cheese with big eyes
The application of Holdbac YM-B is advantageous for you in two ways:
Inhibitation of clostridia and heterofermentative lactobacilli
Desired eye formation by the propionic acid bacteria contained in Holdbac YM-B
Inhibition of the growth of yeasts and moulds
Suppression of undesired gas-forming lactobacilli and wild Leoconostic-strains
Semi-hard cheese ripened in foil
A treatment of the surface (spraying of a Holdbac YM-B-solution) directly after the brine bath inhibits the growth of fungus, if the foil should have been damaged.
Following are available for application:
Holdbac YM-B LYO 100 DCU
Holdbac YM-B LYO 500 DCU
Holdbac YM-C LYO 500 DCU