Liquid rennet extract. Soxhlet gave an easy and simple way to prepare a permanent rennet extract, which can be advantageously used in any cheese factory.
Dried and decayed abomasum are carefully cleaned of meat parts, cuts into small pieces (about 1 cm2) and covers it with water, counting on 100 g abomasum 1 l of water. Apart from water, we give each one 100 g abomasum 50 g table salt and 40 g of boric acid, then leave the mixture on 5 days at room temperature, stirring from time to time. After 5 days are given for every liter of water used again 50 g of table salt and ceed or filter the mixture through filter paper. WITH 1 1 of the mixture will then give approx 800 cm3 of the filtrate, which complements to 1 l pouring 200 cm3 of a 10% common salt solution saturated with boric acid (so much boric acid is being given, until it stops dissolving). Now the rennet is ready. Its power weakens slightly in the first two months, then it is determined and amounts to approx 1 : 10 000.
In this case, a germ-free rennet is obtained. A good rennet extract should be clear and only have a weak one, but a pleasant fragrance. Fresh abomasum extract is cloudy and contains a lot of undesirable mucus (mucins).
The rennet should be stored in tightly corked dishes in a cool and dark place, as the rennet enzyme breaks down slowly with air and sunlight, hence it loses its power.
Who cares about a very strong rennet lift, this one can get it, changing stomachs during maceration twice or three times.