Et ürünlerinde lactik asit bakterisinin etkisi

Ek : 1


Lactic acid bacteria of meat and meat products
AUBREY F. EGAN
CSIRO Division of Food Research, Meat Research Laboratory, P.O. Box 12,
Cannon Hill, Queensland, 4170, Australia
EGAN, A. F. 1983. Lactic acid bacteria of meat and meat products. Antonie
van Leeuwenhoek 49: 327-336.
When the growth of aerobic spoilage bacteria is inhibited, lactic acid bacteria
may become the dominant component of the microbial flora of meats. This occurs
with cured meats and with meats packaged in films of low gas permeability.
The presence of a flora of psychrotrophic lactic acid bacteria on vacuum-packaged
flesh chilled meats usually ensures that shelf-life is maximal. When these
organisms spoil meats it is generally by causing souring, however other specific
types of spoilage do occur. Some strains cause slime formation and greening
of cured meats, and others may produce hydrogen sulphide during growth on
vacuum-packaged beef. The safety and stability of fermented sausages depends
upon fermentation caused by lactic acid bacteria. Overall the presence on meats
of lactic acid bacteria is more desirable than that of the types of bacteria they
have replaced.
INTRODUCTION
Fresh meat stored in air spoils rapidly due to the growth of gram-negative
bacteria which cause putrefaction. A number of methods of preserving meats
are known including the traditional ones of salting and curing. When the bacterial
flora of such meats is examined it is commonly found that lactic acid bacteria
are a major component. They are non-putrefactive and when sp~oilage does occur
it is usually due to souring.
Lactic acid bacteria are able to grow under a variety of conditions which prevent
the growth of gram-negative aerobes such as pseudomonads. Lactic acid
bacteria do not require oxygen for growth, are resistant to inhibition by carbon
dioxide, nitrite and smoke and are able to grow at relatively high salt concentrations.
Further, they tolerate lower pH values than the gram-negative bacteria...

Devamı...

Dosya Türü: pdf