PASTEURISATION.

New Zealand Times, Volume XXXII, Issue 7077, 15 March 1910, Page 4

PASTEURISATION.

(KEW ZEALAND AGAIN IN THE VAN. ÜBTOJ>ATH SOUTHERN PLANT AND METHOD. Not since the factory method of butter manufacture was established in this country has there been introduced a movement so far-reaching in its effect on butter quality as that of cream pasteurisation, which is revolutionising our system of manufacture, and has this season -brought -about a very gratifying advance in the standard of our export butter. Pasteurisation, of cream is not a new idea. It has long been in vogue iu the country of our great rivalsDenmark. That its value has not been appreciated by New Zealand buttermakers before is due to several causes. In tho first place it was not considered that there waa the need for it. Obviously, if a. butter can be made from non-pasteurised cream, with a clean flavour, and of good keeping quality, there is not the necessity to invoke the aid of pasteurisation, while there are many who prefer the high quality butter made from the milk of grass-fed cows to any artificially flavoured butter. on British markets, however, tho pasteurised butter of Denmark—clean and mild flavoured —is so popular that this preference hardly exists; in fact, whatever advantage the non-pasteurised butter may possess in Britain it is entirely discounted, at least so far as butfer from this distant source is concerned, by reason of its want of uniformity; and uniformity—the outstanding advantage of pasteurisation—is a market consideration of the first importance. WINKING BACK A EEPTJTATION. While there was a few years back in the argument that there was not tho need for pasteurisation—in

-' rthe days -when New Zealand batter was v made on a careful system (as much of •the moisture and other deteriorating ■'; media as possible being worked out of iy—the position, has somewhat -.-hanged 'with the use of the labour-sa... ;,' com- .. tbined churn, ami the resuming ini scuease, in moisture content Pasteurisa"±ion has, in. fact, become, imperative to the regaining of war old-time repa'tation, and while it is doing this it id afioctrng an improvement which was itoi possible of attainment under the old •system—uniformity in the general character of New Zealand butter. While the combined churn is mainly responsible • for the general adoption of aream .pasteurisation, its was ifarood on the notice of one or two fac:tories within the last few years aa the one means of correcting unsatisfactory quality. The prdnciplo really means ~ -..destroying, the bacteria responsible for fermentation "activity in the cream, -desirable or otherwise, and then by the introduction of a specially prepared culture of tne lactici acddi (the germ ~ cansittg the fermehtatKm of the , milk isugar) to give the cream a clean and natural flavour. AIMING AT THE TTNATTAINABLE. One reason, why this obviously desirable principle- was not availed of before is that leaders in the dairying world of this country in the past preached the * doctrine —sound enough, but -weak, because unattainable—that pasteurisation was a remedy for ai defect that should mot exist. As one conservative authority in the South out it, " The beet paeteurieer ia a scrubbing brush." If it were possible to daaw and handle all milk tmder ideal oonditkma and get it into the hands of the buttermaker within - a few hours, £he argument would be all rjjght, but aa theeo requirements are impossible of attainment the remedy pasteurisation! offers must be availed of. THE SOUTHERN WESSON.

A company which needed pasteurisation, perhaps more, than, amy'.other has been, one of the last to realise its advantages. This is the Taieri. and. Peninsufo Mili Supply Company, of Dunedtn. It «k>manded the assistance of pasteurisaiaan because of tho greasfc area from which it gathers its cream, bat it was loth to adopt the oorreotive treatment ■because it Relieved it possible that tho great disadvantage under which it •was labouring could bo overcome by other means. Now. however, that the company bits adopted pasteurisation it is taEing ■op the question in. a thoroughgoing manner. A plant has been installed which, • while thoroughly efiective, presents an admirable feature which must yet be«ome general in oroam and milk pastenr.ieing operations. This is the provision . of a holding chamber, or "sterilising : pot," an insulated apparatus (a jacketed .vessel of the size and external form of the pasteniTtie-r) into which the cream is . "run from the pasteuriser, .entering the 'vessel at tho bottom. Then, by means .of revolving agitators the cream is. kept - moving towards the top outlet, the essentia! fea/tnre being that the agitators can be so regulated in speed that the cream . can bo held in the vessel for about fifteen minutes, or less if needed. Thus, instead of taking the cream up to, say, 185 or 190 deg.. to make sure of effective pasteurisation, a lower decree can be omployod. say, ITStieg.. or even lGadeg.. * and by reiison of being retained for the fifteen minutes at those lower temperatures the pasteurisation is just as effec-

tivo as if tho higher degrees of heat were employed. The " T and P method has proved to bo thoroughly successful. A .proof of this is fpraished-by tho <"fl€Ct on rniik intended for city supply purposcs wiieh is pasteurised ini tho same -way. Milk drawn the previous evening, at iprobably a hundred miles distant, is pasteurised and not sent out till the day after it is received, let this wOl xomoan Bweot till tho day following that o» which "It is delivered to the consumer. Aa this milk oomes from tho cooler a slightly cooked smell can bo detected wubn standing ovor the vat, But when the milk has been standmjr in the cans for a short time, prior to these being placed in, a cool chamber, the taste is excellent—sweet and agreeable. In the oaso of the cream pasteurisation the quality of the butter being turned out this season by the big Southern company ia ample testimony to its elhcacy. For somo years Bhe quality of the ' T. and P." brand "has not been satisfactory, and last season's was so disappointing that pasteurisation was adopted on the advieo of State experts as an imperative measure. Tho result has been to bring the brand up to a very high plane, 05 ipoints being mow a common. score. A NEW PASTBITEISBE.

While satisfactory pasteurigins work is now beims: done in the "T. and P." factories, a pasteuriser is about to bo installed which, with tho capital "holder idea adopted by the company, should spell the last word in the work of pasteurising. It is an 'idea of'the Anderson Company, of Dunedin, tho Southern pioneers in dairy plant manufacture. Thanks to the proximity of his workshop to the "T. and P." factory, and the opportunities there afforded for experimental work, the former senior member of tho firm, Mr Anderson, in conjunction! with Mr Biddel, general manager of the T. and P. Company, evolved several valuable ideas in connection with factory hutteTinaking plant. Good as these have been they have-been surpassed by the pasteuriser the present head of the Anderson firm, Mr J. Hunter, one of the most popular men in the business, is manufacturing. GBEAT DRAWBACKS EEMOVED. Ono of the. great drawbacks _to effeo. tivo and economic .pasteurisation with the pasteuriser in general use is the tendency for £he milk to burn on the heating wall. Where {hia occurs the burnt caseine acts as an insulator. This not only reduces the pasteurising capacity, but has a .tendency to taint: the cream. So serious is the difficulty that two machines have had to bo installed in'some factories. The main reasons for the burning on aire that the heat is obtained by the application of live steam, and there is no provision for preventing the cream adhering to the sides of the heating chamber. The new Anderson pasteuriser overcomes both these drawbacks. Here hot water is the heating agent, the water in the jacket being brought -up to the desired temperature by means of steam, introduced through a perforated ring in the bottom of the machine. Thus the heat applied to the outside wall of the heating chamber is more uniform, and" the risk of " burning on " is, therefore, greatly reduced. The other idea, however, quite prevents damage to the cream from this cause. To ithe skies of the agitators are attached ■brushes, made the full depth of the machine, and these keep the walls of the healing chamber quite clean, thus effectively preventing 'burning eta." The new is, of course, patented. In its present form it is IrigMy praised by leading experts, who believe it will remove all drawbacks to factory pasteurisatioji eot far experienced, j Dairyman! of this island will have an appoitanity of studyinjr it for themselves at the forthcoming National DairyShow.