BioRen® Dried Calves' Vells

BioRen® Dried calves' vellsDried rennet stomachs have the longest tradition in cheese production – they therefore could be called the original rennet. If it is assumed that cheese production commenced around 4500 BC, cheese-makers have been procuring and drying stomachs and then using them to produce rennet for more than 6000 years. The industrial production of rennet only commenced around 160 years ago. This shows how natural rennet is inseparably linked to cheese as a product.

Some regions still require dried calf vells for the production of certain types of cheeses. To this end, the company dries selected vells from young New Zealand milk-fed calves. These are washed by hand, tied and inflated and dried as gently as possible in special air chambers.


Hundsbichler's rennet stomachs are only produced with raw materials procured from selected and monitored abattoirs in New Zealand and Australia. The stomachs used are exclusively from "first grade bobby vells". The raw materials are deep frozen when they arrive at the company. On arrival, they are defrosted and subjected to a preliminary selection process. They are then thoroughly washed, tied, inflated with air and dried very carefully in drying chambers with circulating air. This drying process is followed by a second selection run and finishing.

Quality and packaging units

Only top quality dried rennet stomachs are produced. They are available singly or in bundles of 12.

Natural rennet
is profitable
because it delivers
the highest possible
cheese yields.


Several stomachs are bound together into a firm roll and cut into small slices. The slices are then put into containers with liquid whey for overnight incubation at a slightly elevated temperature of around 30°C. The liquid is then filtered through cloth so as to remove all solids. The rennet strengths or the required quantity of rennet stomachs is empirically determined by a spoon test. If necessary or desired, natural rennet powder or natural rennet extract is added to set the correct coagulation time.

Further developments

The positive effect of dried rennet stomachs on cheese qualities and yields is beyond dispute. However, it is also certain that this classical natural product is difficult to use and requires great care. This is why the company developed its natural rennet liquid paste. This paste contains all the positive components of rennet stomachs and even more as it offers the benefits of simple handling, storage and reproducible application.


Dried rennet stomachs contain the entire spectrum of enzymes and bacteria that profound cheeses demand. Better taste, shorter maturation times and maximum cheese yields are the greatest benefits that this product provides. Hard cheeses, for example, Emmental, Bergkäse (mountain cheese), Gruyere etc., are the classic types of cheese that gain from this product. The variety of natural enzyme complexes contained only in natural rennet, guarantees the best possible cheese yields and taste. Over millions of years, evolution has developed these enzymes to perfection. Consequently they cannot be reproduced by man-made coagulants. This is something that Darwin would have readily confirmed.