Growth and colour development of some surface ripening bacteria with Debaryomyces hansenii on aseptic cheese curd.
The growth of five bacteria isolated from red-smear cheeses, Brevibacterium aurantiacum, Corynebacterium casei, Corynebacterium variabile, Microbacterium gubbeenense and Staphylococcus saprophyticus in mixed cultures with Debaryomyces hansenii on aseptic model cheese curd at 10 and 14 degrees C was investigated. At both temperatures, C. casei and Micro. gubbeenense had a longer lag phase than C. variabile, Brevi. aurantiacum and Staph. saprophyticus. In all cultures, lactose was utilised first and was consumed more rapidly at 14 degrees C than at 10 degrees C, i.e., 6 d at 14 degrees C and 10 d at 10 degrees C. This utilisation coincided with the exponential growth of Deb. hansenii on the cheese surface. Lactate was also used as a carbon source and was totally consumed after 21 d at 14 degrees C and approximately 90% was consumed after 21 d at 10 degrees C regardless of the ripening culture. Small differences (<0.5 pH unit) in the surface-pH during ripening were noticeable between ripening cultures. Differences in the colour development of the mixed cultures with the yeast control were only noticeable after 15 d for Brevi. aurantiacum and after 21 d for the other bacteria. Regardless of the organisms tested, colour development and colour intensity were also greater at 14 degrees C than at 10 degrees C. This study has provided useful information on the growth and contribution to colour development of these bacteria on cheese.
Mounier
Jérôme
J
Dairy Products Research Centre, Teagasc, Fermoy, Ireland.
Irlinger
Françoise
F
Leclercq-Perlat
Marie-Noëlle
MN
Sarthou
Anne-Sophie
AS
Spinnler
Henry-Eric
HE
Fitzgerald
Gerald F
GF
Cogan
Timothy M
TM
D001951:Brevibacterium / Q000254:growth & development; D002611:Cheese / Q000382:microbiology*; D015169:Colony Count, Microbial; D003116:Color; D003352:Corynebacterium / Q000254:growth & development; D005285:Fermentation; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D006863:Hydrogen-Ion Concentration; D004718:Saccharomycetales / Q000254:growth & development* / Q000378:metabolism; D013210:Staphylococcus / Q000254:growth & development; D013696:Temperature; D013997:Time Factors