The rind seems to be the least important part when we eat cheese. We even usually discard it, and there is sometimes some doubt as to whether it is edible.
However, rind plays a very important role in the preparation and final quality of the food, because it helps to preserve the fermentation processes that take place in the mass, while at the same time protecting the cheese from major external problems such as contamination.
Natamycin and other food preservatives are applied to cheese rind to ensure that it performs its protective role against external contamination due to fungi and yeasts, and at the same time it does not interfere with or change the organoleptic characteristics of the end product.
There are almost as many types of cheese rind as there are varieties of product. The rind is formed during as the cheese ripens, as the exterior of the cheese naturally becomes a physical medium for microscopic moulds and yeasts. The increasingly dense coloured layer is visible to the naked eye, and contrasts with the more or less whitish tones of the inside of most cheeses. However, if this external colonisation is not brought under control, there is a risk of invasion and contamination of the manufactured product. This is why the application of food preservatives such as natamycin on the outside of the cheese is so important, and the amount allowed by the current legislation must always be used.
Types of rind and their composition
Rinds must perform the important task of ensuring that the cheese is of the highest quality from the time it leaves the store to its point of sale, which is why one or more ingredients are used in the rind.
The following table summarises the treatments that can be applied to the surface of the cheese and which create the rind:
An example of microorganisms in rind other than internal fermenting agents are the white moulds that are used to coat cheeses like Brie and Camembert, which have an edible white rind which also complements the flavour of the internal mass of these varieties of cheese.
Paints are applied to the outer part of the cheese, in the form of a packaging film insulating the pieces of some cheeses. This rind may be composed of gums, celluloses and waxes, or it can consist of paraffins. As not all products applied to rind are edible, the final cuts of cheese include the warning “inedible rind” when this is necessary, to remind consumers to remove that part of the cheese when they consume it.
The combinations of treatments generally applied in industry are summarised in the table above. Combined applications of microorganisms and paints together with food additives such as Natamycin provide a shell that is also protected against unwanted contamination.
As it does not affect the characteristics of the end product, Natamycin can be added to natural and artificial rinds.