Kefir yeast technology: scale-up in SCP production using milk whey.
A three-step process to scale-up kefir biomass production at a semi-industrial scale employing whey is reported. Aerobic fermentations were initially performed at laboratory scales, in 1.5- and 4-L bioreactors, yielding 79 g/L final kefir biomass (0.89 g/g of lactose utilized), in 7 h of fermentation time. The use of whey as carbon source even in solid cultures led to the formation of a granular biomass. These results encouraged scale-up at a semi-industrial-scale pilot plant employing 100- and 3,000-L bioreactors, leading to the development of a process for granular kefir biomass production. The results validated the laboratory-scale experiments and the avoidance of centrifugal separators due to granular biomass formation. Pilot-plant operations showed kefir to be highly resistant to contamination under actual industrial conditions and no serious problems in handling of raw materials and equipment were observed. Economic analysis showed a 20% higher cost of the market price of products, with added value of up to 15.9 x 10(9) within the European Union.
Koutinas
A A
AA
Food Biotechnology Group, Department of Chemistry, University of Patras, Patras, 26500 Greece. a.a.koutinas@upatras.gr
Athanasiadis
I
I
Bekatorou
A
A
Iconomopoulou
M
M
Blekas
G
G
D000332:Aerobiosis; D018533:Biomass; D019149:Bioreactors; D001709:Biotechnology / Q000191:economics / Q000295:instrumentation* / Q000379:methods; D043302:Cultured Milk Products / Q000378:metabolism*; D008894:Milk Proteins / Q000378:metabolism*; D010865:Pilot Projects; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000378:metabolism*; D000067816:Whey Proteins
D008894:Milk Proteins; D000067816:Whey Proteins