Causes and Control of Culture-Related Flavor Defects in Cultured Dairy Products

Research publications on culture-related flavor defects in fermented dairy products are reviewed. Bitterness and fruity off-flavor in Cheddar cheese, caused by the production of bitter peptides and ethyl esters of fatty acids respectively by starter bacteria, are discussed. Lack of diacetyl flavor in Cottage cheese, cultured buttermilk and sour cream is viewed as a major flavor defect in products being marketed today. Cultures may destroy diacetyl by com,erting it to acetoin and in the case of Cottage cheese, culturing of the dressing with flavor organisms is recommended to enhance flavor, Harsh or green flavors in fermented products caused by excessive acetaldehyde production may be controlled with starter strains high in alcohol dehydrogenase (aldehyde reductase) or by ensuring that high populations of Leuconostoc are present by adding them as concentrates. For yogurt, however, Technical Paper 3160 Oregon Agriculture Experirnent Station.