Holdbac

Application and effects

In the food industry, undesired microorganisms represent a certain danger - they limit the shelf life of foodstuffs and often represent a danger to health. Preservatives have a bad reputation due to their negative effects on the human organism in case of high administration. Therefore, they are mostly not allowed for application in dairy products.

Danisco offers - under licence of Valio - with Holdbac a protective culture of which the strains alone resp. in symbiose together inhibit undesired microorganisms in their growth and activity.

What does Holdbac YM-B contain?

* Lactobacillus rhamnosus and
* Propionibacterium freudenreichii ssp. shermani

Which groups of microorganisms are inhibited?

* Yeasts
* Enterococci
* Moulds
* Coliform germs
* Heterofermentative lactic acid bacteria,
* Spore-forming bacteria (bacilli, clostridia)
especially lactobacilli

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 acid and propionic acid. Furthermore, it produces other acids and small amounts of diacetyl. 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 considerably lower inhibiting effects than combined with the culture, i. e. the cell substance together with the metabolic products causes the protective effect against yeasts and moulds.

The inhibition 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

Yoghurt/Fermented milk products - Inhibition of growth of yeasts and moulds
Yoghurt had been fermented in laboratory test with a starter culture of Streptococcus thermophilus and Lactobacillus bulgaricus. 0.1 % of Holdbac YM-B (= cell count 107/ml yoghurt milk) had been inoculated at the same time with the starter culture into the yoghurt. Strawberry marmalade had been contaminated with Rhodotorula sp. yeast.

Quarg - Inhibition of growth of yeasts and moulds

Practical tests with:
1. Holdbac YM-B 0.01 %
2. Holdbac YM-B 0.1 %
3. Sorbic acid 0.06 %
4. Quarg without additives as reference

Holdbac YM-B had been added to freshly fermented quarg mass in an amount of 0.01 % and 0.1 %. The cell counts in quarg ran up to 106 cfu/g and 107 cfu/g. Calcium sorbat had been suspended in water and added in doses so that die concentration in quarg was at 0.06 %. The quarg had been stored at + 6 °C for five weeks.

Inhibition of Rhodotorula sp. in quarg by Holdbac YM-B and
sorbic acid and without any additive as reference

Cheese with big eyes:

The application of Holdbac YM-B is advantageous for you in two points:
1. Inhibition of clostridia and heterofermentative lactobacilli
2. Desired eye formation by the propionic acid bacteria contained in Holdbac YM-B

Feta/Cottage cheese

Inhibition of the growth of yeasts and moulds
Suppression of undesired gas-forming lactobacilli and wild Leuconostoc-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.

The following sales forms are available for application:

Holdbac YM-B  PELLET

Holdbac YM-B LYO 100 & 500 DCU

Do not hesitate to call us, we will give you detailed advice!