RENNET-MAKING.

New Zealand Journal of Agriculture, Volume XIII, Issue 3, 20 September 1916, Page 224

RENNET-MAKING.

SAVING OF CALVES’ VELLS.

In connection with the steps taken recently by the producers’ organizations to ensure future supplies of rennet for the cheesemaking industry, demonstrations of the approved method of saving calves’ veils are being given by officers of the Live-stock Division throughout the dairying districts. The following description of the process, together with diagram, has been issued as a new edition of Bulletin No. 61, “Preparation of Calves’ Veils for Rennet-making.”

DIRECTIONS FOR SAVING THE VELL (AIR-DRYING METHOD).

The “ veil ” is the fourth or true stomach of the calf, and is used for the manufacture of rennet. Only the veils from sucking or milk-fed calves are valuable for this purpose. The veils of calves raised on grass or other solid foods are not suitable. Calves slaughtered for their veils should not be less than three or four days old.

When the calf is killed, immediately take out the veil, which in the young calf is the largest stomach of the four and connects directly with the bowel. The process is as follows :

With the open carcase lying on its back, and the operator facing the head of the calf, first find the lower end of the veil where it connects with the bowel, over the liver. Then locate the two small stomachs (‘ book ”* and “ honeycomb ”), which will be found close together attached to the upper end of the veil — book on the left and the honeycomb a shade higher up on the rightas shown in the illustration on back page. These two stomachs will be empty and only slightly larger than a -piece. Now cut the bowel, leaving a few inches

attached to the veil; lift the veil towards the chest-cavity and cut it clear, leaving the book and honeycomb attached. When the veil has been thus secured, remove the few inches of bowel by cutting immediately above the junction between the stomach and the bowel, which feels like a hard knot close to the outlet from the veil. Then expel carefully the whole, contents of the veil through the gut end by passing the veil a few times between the forefinger and thumb. Now

remove the honeycomb and other adhering parts, leaving the book still attached. Tie a string tightly round the narrow neck between the veil and book, and then cut away the latter, leaving only sufficient of it to prevent the string from slipping. Insert a tube in the gut end, blow up the veil fairly hard like a bladder, and tie securely. Remove any adhering fat and tissue, taking care not to dress too close to the veil, as by doing so it may be weakened sufficiently to permit the escape of the air, in which case the veil would be rendered useless.

Hang the inflated veils in a draughty shed or a warm dry room, but do not expose them to more heat than that of an ordinary warm room. Never hang veils in the open exposed to the sun. Where a good draught can be created it will help to dry the veils quickly, and the process should not take more than a week. They should not be left moist long enough to mould or putrefy, and care should be taken that they are not infested with maggots or insects after being dried and bundled for despatch. In other words, they should be thoroughly dried and carefully protected from flies and other insects.

. '' When a sufficient number of thoroughly dried veils have accumulated cut off the neck (which contains but little of the ferment) and let out the air; tie up the veils in bundles, and pack carefully for despatch to the collecting-depot or dairy factory as directed.

* The “ book ” is better known in New Zealand as the “ bible” or “ manyplies.”