Improve cheese quality with new starters.

The development of new cheeses and the acceleration of existing manufacturing procedures will result from studies carried out by six dairy research groups from European universities and industry. The consortium intends to provide the European dairy industry with tools, such as debittering and high-lysing starter cultures, that would improve the quality of cheese.

These practical tools could yield a competitive advantage over other major dairy-producing countries such as United States, New Zealand and Australia. Results from this work could also promote future developments in industries that use fermentation for the manufacture of foods other than dairy products.

Starter cultures are at the heart of this research. They produce the enzymes that contribute to the development of cheese flavor by breaking down and converting milk fats and proteins, the flavor precursors. At first, bacteria have enough energy to take the precursors inside themselves, but breaking these molecules down requires so much energy that this ability soon disappears. So, flavor development can only happen when the starters crack open, liberating the flavor enzymes into the media that surround them.

Food technologists know how to enable this break, which they call lysis. However, they do not know much about the actual mechanism by which it takes place. More importantly, scientists ignore what would happen by increasing and accelerating this process. In order to better understand starter lysis and its role in cheesemaking, several popular European cheeses such as Cheddar, Danbo and Gouda were studied both in the laboratory and at pilot scale by the research team.

Early testing carried out by the team generated some promising results. For example, highly autolytic starters were selected, and taste panels showed that adding these strains to a bitter starter improved the cheese's sensory traits. The autolytic strains were produced on an industrial scale for testing at trials.

Further information. Jeroen Hugenholtz and Wilco Meijer, NIZO Food Research, P.O. Box 20, 6710 BA EDE, The Netherlands; phone: [phone]; fax: [phone]; email: [e-mail] or [e-mail].