Brevibacterium linens -: a useful enzyme producer for cheese:: a review

Brevibacterium linens is present mainly on the surface of many sorts of surface ripened cheeses. The organism exhibits a distinct rod (0.6-1.2 x 1.5-6.0 mum) in young and coccus in older (3-7 days) cultures. B. linens is strictly aerobic, non motile, gram-positive and grows between 20 and 35 degreesC on a number of different media. B. linens produces red or orange-coloured pigments of aromatic carotenoide type which are not common in other bacteria. This alcalophilic bacterium is able to produce methanethiol from L-methionine and tolerates a high NaCl concentration up to 15%. B. linens produces antimicrobial substances which inhibit the growth of many Gram positive food poisoning bacteria as well as several yeasts and moulds. B. linens synthesizes highly active and multiple proteolytic enzymes during its growth. Extracellular proteinases of B. linens have alkaline pH optima and are capable to hydrolyze both alpha (s1)- and beta -casein to a peptide of relatively high molecular weight. In acceleration of cheese ripening process, it is possible to improve flavour and eliminate bitterness with the use of enzymes from B. linens alone or in combination with commercially available enzymes.