NEW FACTORY PROCESS

Wanganui Chronicle, Volume LXXXIII, Issue 19512, 15 February 1926, Page 9

NEW FACTORY PROCESS

RECOVERY OF MILK SOLIDS. \ DAIRYING ADVANCE. SPECIAL TREATMENT OF WASTE. Further details concerning the process invented by Mr 11. N. McLeod, of Frankton, for substantially increasing the value of dairy produce by extracting from 10 to 13 per cent, more solids from the milk than can he, done by ordinary methods, reveal how important the invention is, states the Hamilton correspondent of the “New Zealand Herald.” The process saves valuable solids in whey and butter-milk which have previously been regarded as waste matter, and converts these solids into additional food by cheaply and effectively incorporating them with fullcresm milk cheese, which, by the addition. is also increased in nutritive value and is exceedingly pleasant to the, palate. Where it has been placed on the market the new cheese has become highly popular. It is stated to be a scientific fact that the quantity of solids left in skim milk and butter-milk is three times greater than the quantity of butter-fat taken out. To convert these waste solids into additional cheese has been Mr McLeod’s object, and he has had considerable success. It is estimated that if the system is fully developed in [New Zealand a gain of £6,000,000 annually will be given to the dairy tryOutline of the Process. The plant consists of a pump and a prccipitor, so called because it brings about the precipitation of the fine curd. The buttermilk or whey is pumped from the churn or vat into the precipitor, and steam, registering up to 320 degrees, is applied at high pressure. The liquid is then regeneratively cooled and passed through an extractor. Solids in the form of very fine curds are retained, and are incorporated in the next day’s make of cheese. The solids from butter-milk have a bright white appearance, and are like white of egg, while the solids from whey are pink in colour. Some idea if the value of the process may be gleaned from the fact that of 12.70 per cent, of solids in whole milk, 9.40 per cent, is retained in the butter-milk. Butter is represented by about 3.30 per cent. The proportion of butter to the buttermilk is about as 40 is to 60. By applying the McLeod process half-a-pound of solids can be, obtained from a gallon of butter-milk. Mr McLeod’s invention was the result of investigations made in Southland with a view to finding some means of doing away with the pollution caused in streams by whey. An Authoritative Report.

Reporting on the process, Mr H. AV. Lawrence, F.1.C., F.C.S., who was 18 years with the Royal Agricultural Society, England, gives the following interesting information: —“The whey obtained as a by-product of cheese-mak-ing and subsequent separation to remove the remaining butter-fat, contains a considerable quantity of solids, amounting to approximately half the quantity originally in the milk. Whole milk contains an average of 12.5 per cent, total solids, which consists of milk fat, casein, lactalbumin, milk, sugar and mineral matter. In the process of making cheese most ot the fat and casein are removed, while the small quantity of fat remaining in the whey is almost entirely removed by the separation in a milk separator. The whey thus obtained still contains so: 6.6 per cent, total solids comprising milk sugar, casein, lactalbumin, some of the mineral matter a, d a very small quantity of fat. In' other words the protein remaining in a typical whey amounts to, roughly, between one-sixth and one-seventh of the total solids removed from cheese, or, if an average milk contains 3.4 per hundred of total protein, 2.6 parts, or roughly threequarters of the total, -re removed in the curd from cheese, while 0.8 parts, or roughly one-quarter of the total remains in the whey. The object of the McLeod patent whey apparatus is to extract further solids from the whey

by precipitation. As a factory process it is simple and economical.” Dealing with the technical aspects, Mr Lawrence further states: “The results prove that the process extracted 0.55 per cent, of the protein, which together with the sugar, ash and fat precipitated with it, would amount to 0.7 per cent., which is equal to mor" than .10 per cent, of the cheese solids extracted from a typical milk.’’