Whey-cheese production using freeze-dried kefir culture as a starter.
OBJECTIVE
The aim of the present study was to evaluate the use of a freeze-dried kefir culture in the production of a novel type of whey-cheese similar to traditional Greek Myzithra-cheese, to achieve improvement of the quality characteristics of the final product and the extension of shelf-life.


RESULTS
The use of kefir culture as a starter led to increased lactic acid concentrations and decreased pH values in the final product compared with whey-cheese without starter culture. The effect of the starter culture on production of aroma-related compounds responsible for cheese flavour was also studied using the solid phase microextraction gas chromatography/mass spectrometry technique. Spoilage in unsalted kefir-whey-cheese was observed on the thirteenth and the twentieth day of preservation at 10 and 5 degrees C, respectively, while the corresponding times for unsalted whey-cheese preservation were 11 and 14 days.


CONCLUSIONS
The cheeses produced were characterized as high-quality products during the preliminary sensory evaluation. An indication of increased preservation time was attributed to the freeze-dried kefir culture, which also seemed to suppress growth of pathogens.


CONCLUSIONS
The results suggested the use of kefir culture as a means to extend the shelf-life of dairy products with reduced or no salt content.
Dimitrellou
D
D
Food Biotechnology Group, Section of Analytical Environmental and Applied Chemistry, Department of Chemistry, University of Patras, Patras, Greece.
Kourkoutas
Y
Y
Banat
I M
IM
Marchant
R
R
Koutinas
A A
AA
D002611:Cheese / Q000032:analysis / Q000382:microbiology*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D043302:Cultured Milk Products / Q000382:microbiology*; D005504:Food Analysis / Q000379:methods; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods; D005612:Freeze Drying; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009812:Odorants; D013649:Taste