Microbiology of starter cultures

This article discusses the origins and role of starters in dairy fermentations, the ecology of starter bacteria, the classification of starter bacteria,  the types of starter culture used and concludes with some observations on artisanal cultures. The author has  provided a broader perspective on the use of starter cultures in food fermentations in the Encyclopedia of Food Microbiology. The chapter can be downloaded from Elsevier Ltd.

Ecology of starter bacteria

So where did modern starter cultures come from? Most starters in use to today have originated from lactic acid bacteria originally present as part of the contaminating microflora of milk. These bacteria have probably originated from vegetation in the case of lactococci (Sandine et al., 1972) or the intestinal tract in the case of Bifidobacterium spp., enterococci and Lactobacillus acidophilus.

Read more ...

Differences between cheeses

There are many ways in which traditional cheeses can be classified. Criteria such as country of origin, type of milk used, species of animal used to produce the milk, fat content, moisture content, texture, whether mould ripened or not, cheese making process used, moisture in the non-fat solids have been and continue to be used. These criteria have been used either singly or in combination.

These descriptive approaches are limited in that they provide no theoretical insight into why one cheese is different from another.  In other words, why is Gouda cheese different than Cheshire or what makes Emmental different than Cheddar cheese?

For many years researchers in New Zealand, the UK, Ireland, the Netherlands and elsewhere were aware that there were significant differences in the pH and mineral concentrations of the major cheese varieties. 

Read more ...

How do you get the sweetness of ice cream or gelato just right?

Ice cream and gelato manufacturers produce products with a range of favours. There are often significant variations in sweetness and hardness between flavours. This article provides an explanation of sweetness, how it is measured and how it can be controlled.

Relative sweetness and the Potere Dolcificante method are discussed and calculations are used to explain the differences. The limitations and disadvantages of using numerical values of sweetness are explained. Since sweetness and hardness are closely related the reader is also referred to the article on controlling hardness or resistance to scooping.

Read more ...