Survival of cheese-ripening microorganisms in a dynamic simulator of the gastrointestinal tract.

Survival of cheese-ripening microorganisms in a dynamic simulator of the gastrointestinal tract. Food Microbiol. 2016 Feb;53(Pt A):30-40 Authors: Adouard N, Magne L, Cattenoz T, Guillemin H, Foligné B, Picque D, Bonnarme P Abstract A mixture of nine microorganisms (six bacteria and three yeasts) from the microflora of surface-ripened cheeses were subjected to in vitro digestive stress in a three-compartment "dynamic gastrointestinal digester" (DIDGI). We studied the microorganisms (i) grown separately in culture medium only (ii) grown separately in culture medium and then mixed, (iii) grown separately in culture medium and then included in a rennet gel and (iv) grown together in smear-ripened cheese. The yeasts Geotrichum candidum, Kluyveromyces lactis and Debaryomyces hansenii, were strongly resistant to the whole DIDGI process (with a drop in viable cell counts of less than <1 log CFU mL(-1)) and there were no significant differences between lab cultures and cheese-grown cultures. Ripening bacteria such as Hafnia alvei survived gastric stress less well when grown in cheese (with no viable cells after 90 min of exposure of the cheese matrix, compared with 6 CFU mL(-1) in lab cultures). The ability of Corynebacterium casei and Staphylococcus equorum to withstand digestive stress was similar for cheese and pure culture conditions. When grow in a cheese matrix, Brevibacterium aurantiacum and Arthrobacter arilaitensis were clea...
Source: Food Microbiology - Category: Food Science Authors: Tags: Food Microbiol Source Type: research