Some of the key topics at this year’s Cheese are the importance of pastures, raw milk and animal welfare, but the problematic question of starter cultures is also on the agenda. The choice between native bacteria and selected, off-the-shelf starters is not an easy one but it can contribute to preserving the sensory properties that identify a quality cheese.
Cheese 2013 will be exploring this issue in one of its Milk Workshop debates. Experts in the field will be participating in “Natural or Selected? The role of fermentation for a quality cheese,” held on Monday, September 23 at 11 am at the Slow Food stand.
The starter bacteria that convert milk sugars into lactic acid, an essential step in most cheesemaking, can be found on the cheesemaker’s hands, on the animals’ udders or on the tools used during production. However, the number of naturally present, native bacteria has decreased drastically over the past few decades due to the introduction of new materials and ultra-hygienic techniques that eliminate the bacterial flora naturally present in milk. This is a great improvement if the only aim is to ensure food safety, but a disadvantage for the sensory qualities of the final product, as it results in standardized flavors and aromas. In fact, in addition to being the ingredient that distinguishes one cheese from another, bacteria are fundamental to the process of turning milk into cheese. These days, it is common to use commercially purchased, “off-the-shelf” starter cultures to make up for the fact that the milk is “too clean.” This proliferation of commercial starter cultures is endangering the extraordinary heritage of biodiversity found in the cheesemaking world by compromising the sensory quality of products which have a long history behind them. This problem is not confined to industrial cheese production, but also affects artisanal producers, who still use traditional methods, because adding a commercial starter culture simplifies the cheesemaking process, yielding a hygienically safer and more consistent product.
Commercial starter cultures are not the only solution to this problem though; alternatives that respect traditional biodiversity and do not contribute to the standardization of flavors exist. For example a natural starter culture, a sort of “mother,” can be obtained from milk or whey. When using milk, it must come from two or three farmers and be heated to 63-65°C, then cooled to 45-48°C, the best conditions for bacterial multiplication, until the milk coagulates.
To find out more about starter cultures: