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Homo- or heterofermentative lactic acid bacteria (LAB)? |
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Homo- or heterofermentative lactic acid bacteria?
One crucial aspect of a successful fermentation is that plant sugars have to be converted into lactic acid as soon as possible. Lactic acid acidifies rapidly, thus lowering the pH and preventing the growth of spoilage bacteria.
Not all types of lactic acid bacteria (LAB) are equally efficient in forming lactic acid. Most of the naturally occuring microorganisms are either not very efficient or even inapt when it comes to utilizing sugar for the fermentation. Only a few particularly suitable strains are able to show economic benefits due to their special properties for the fermentation - and only if added to the silage alive and in sufficient quantities. Even among such suitable types, significant differences may be observed.
Homofermentative lactic acid bacteria
Heterofermentative lactic acid bacteria
Homofermentative bacteria - like the ones contained in jbs pentolac® 200- significantly improve the fermentation of wilted grass silages if compared to heterofermentative LAB and untreated silages. More residual sugar improves both palatability and digestibility. Application of heterofermentative LAB has shown similar results to those of untreated silages. jbs pentolac® 200 was able to reduce the content of ammonia, which suggests a faster fermentation. Similar results could be seen in non-wilted silages below 20 % DM!!!
SAC, Edinburgh, Scotland
grass, 24.6 % DM/red clover, 23.5 % DM
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untreated |
heteroferm. |
jbs pentolac® 200 |
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grass |
clover |
grass |
clover |
grass |
clover |
| pH after 61 days |
4.5 |
4.2 |
4.3 |
4.2 |
3.8 |
3.9 |
| lactic acid (% DM) |
8.9 |
12.0 |
9.6 |
12.5 |
15.7 |
12.9 |
| acetic acid(% DM) |
1.4 |
1.8 |
1.9 |
2.2 |
0.9 |
1.0 |
| ethanol (% DM) |
1.1 |
0.5 |
1.1 |
0.5 |
0.5 |
0.4 |
| residual sugar(% DM) |
2.4 |
3.9 |
2.4 |
0.5 |
5.7 |
4.5 |
| Ammonia(% N-total) |
13.0 |
3.5 |
8.8 |
4.6 |
4.9 |
1.9 |
| DM-losses (% DM) |
9.8* |
n.a. |
8.2* |
n.a. |
2.6* |
n.a. |
*after 26 days of fermentation
Additional information
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