BUTTER MAKING

Wanganui Chronicle, Volume LXXXIII, Issue 19828, 30 April 1927, Page 21 (Supplement)

BUTTER MAKING

IMPROVEMENT OF CREAM

DEODORISATION PROCESS. The deodorisation of cream by vacuum process, was the subject of an address delivered by Mr A. F. Neilson (general manager of the Pihama 1 Dairy Co.) at a meeting of factory 1 managers held at New Plymouth 1 recently. The system outlined marks a new era in butter making, and its use ‘ as a factory unit ensures uniformity of quality and simplifies the work of the factory manager. Mr Neilsen pointed out that two of the chief difficulties with which the i factory manager had to contend in the ' manufacture of butter were:—(a) The ! I bacteria life with which the cream was so often contaminated before it reached s tho factory, and (b) the feed flavours which appeared to be more or less pre--1 valent in all pastures. Tn so far as the • first difficulty was concerned a great deal had been done by the present farm ' dairy instruction system, as well as the farmers themselves in an honest endeavour to improve their methods of 1 working. Pasteuriser Also Used. >• It had to be accepted that the use ■ of the pasteuriser in conjunction with [ the deodoriser was firstly an economi- • cal necessity as a preheater, and . secondly an insurance against life pro- . ducing germs which might not be destroyed at the lower temperatures em- . ployed in deordorisation. Thp control of feed flavours and r other volatile impurities, which were outside the scope of pasteurisation, had ■ become an established fact in treat- [■ ment under vacuum, by which process the manufacture of a uniformly high - grade butter was now very much sim- . plifled. In the deodorisation of cream, care should be exercised in the intensity of ’ the treatment which should be varied according to the quality of the cream. Treatment, Mr Neilsen said, was varied . by:—(1) Quantity of cream fed to the I machine; (2) amount of steam applied. Finest quality cream could be fed to the deodoriser at. the rate of 1006 ’ gallons per hour, first grade at 700 gal- . ions per hour, and second grade at .300 to 100 gallons per hour. With careJ I'ul handling there should be very little . j difference in the three classes of cream , j after treatment. The capacity could b e > reduced to 100 gallons per hour if desired ami the steam so regulated as to ’ give precisely th e same treatment as at the higher rate of feed. At .1,000 gallons per hour the cream would get six minutes treatment, at 700 gallons 8L- minutes, and at 400 gallons , per hour 14 minutes. From the time il. I entered the machine until it was discharged, the cream was subjected to vigorous boiling (from 6 to 15 minutes), travelled from 1:} to 11 miles, and was distributed over an area of 200 square feet at an average depth of one inch. When the machine was working at a low capacity of say 300 or 400 gallons per hour the result was a high degree of concentration, up to 25 or 33 ” per cent., so that a corresponding dilution of the cream before treatment was necessary otherwise it would be inconi voniently thick for churning, and the i resultant butter might, have a con densed milk flavour which was not de- [ sirable. It was found that rather less neutralising agent was required than that pre- ) scribed in the table issued by the Dairy ■ Division, which was no doubt due to the cream being subjected to violent 1 ebullition during treatment. Whey Cream Treated. AVTiey cream was handled similarly to second grade cream, i.e., it was diluted with water or buttermilk and given an intensive treatment. The water after passing through the condenser had a ‘ pronounced whey flavour, indicating 1 that this undesirable flavour in whey • butter had, to a great extent been elim- ’ inated after the cream had been dcl odorised. One special feature in the deodoriser was the absolute consistently even tern- ’ perature at which the cream was discharged from the machine, no matter how irregular the temperatures might be at the inlet pipe. Cream gaining ad- ’ mission at .130 degrees Fahrenheit came in contact with the steam jacket of the deodoriser, and as the distance • of travel was so great, and tho time • it was retained at its greatest capacity was six minutes, it was brought up to the common temperature of the mass and began to boil long before it reached the outlet pipe. That entering ' at 206 degrees Fahrenheit being 26 degrees higher than the boiling-point of the cream in thp. machine, immediately gave off its latent heat and automatic--1 ally followed its course to the outlet, boiling the while at ISO degrees ■ Fahrenheit. I The best results were obtained at a ’ vacuum of just under 15 minutes with ■ a corresponding boiling point of 180 degrees Fahrenheit. I’he eiriiciency of the machine was reduced as a deodoriser when the cream • was fed to it at a temperature below ; that of the boiling-point at which it was regulated, as it was functioning • partly as a pasteuriser in raising the • temperature of such cream, and consequently a. shorter deodorising treat- ’ ment followed. Advice On Working. The vacuum was regulated by means of a “snifter valve” which was set similar to a steam safety valve and worked inversely to it. If the vacuum were allowed to rise suddenly the boiling point would be reduced and a consequent sudden demand on the con- _ denser might cause it, to choke and the cream would boil over, in which case the attendant would have to break vacuum. The snifter valve, however, was perfectly balanced and instantly ; admitted the air required to hold the , vacuum within the prescribed limit. In conclusion Mr Neilsen pointed out i that with the deodoriser, like the pasteuriser, no efforts should be spared to improve and keep improving the quality of the raw material as no mcchaniI cal device ever evolved would be able to redeem milk or cream which had