HIGH OR LOW MILK TEST?

Hawera Star, Volume XLVII, 20 June 1928, Page 8

HIGH OR LOW MILK TEST?

MANY VITAL QUESTIONS ANSWERED

CONCLUDING SECTION OF REPORT

Seeking New Basis of Pay-out

An Epitome of the New Knowledge Gained

The third and final section of the Hawera Dairy Laboratory’s repprt is presented to our readers below. In this the investigator examines very closely the subject of method of payout to factory suppliers in the course of a search for the most equitable basis in the interests of owners of both classes of herds, high and low testing. He has evolved a basis which has hitherto not been in operation and he recommends its adoption until such time as the high testing herds in the cheese producing districts have been replaced by low testing cows. As an alternative Mr. Veale provides a system whereby “penalties” would be imposed with a view to equalising the rate of pay-out as between suppliers of the two varieties of milk. It is recognised by the report that no absolutely faultless, system of payout can be arrived at, but the proposals submitted here are made in the belief that they will do a greater measure of justice to the low test supplier than has been done in the past. In its concluding summary the report answers briefly the questions it asked in opening, stating very definitely in what directions the cheese industry will have to look in order to get the greatest return for its labour and capital. Though doubtless there will be a reluctance in some! quarters to accept the revolutionary changes advocated by this report, which has been first made public through the columns of ‘ ‘ The Hawera Star” it will be agreed that the scientist in charge of the Federation’s laboratory has added considerably to the industry’s sum of knowledge in relation to the particular phase with which he deals — cheese-making in all its stages from the production of the milk to the sale of the manufactured article in the world’s markets.

METHOD OF PAYMENT FOE. MILK FOE CHEESE-MAKING. It has been demonstrated in the previous section from actual market returns, that low testing milk such as that from the Friesian breed is capa.ble of returning to the producer at least 2d per pound butterfat- more than the. high testing milk such as that from the Jersey breed. Under present circumstances all butterfat is paid for by a cheese factory at the same rate each isea.son, whether derived from high or low testing milk. It therefore appears that the present (system of payment for cheese milk by fat alone may be unjust, in that it fails to pay to the producer of low testing milk a fair proportion of what he earns. £ In. order to make this clear, we may imagine that the owners of the three herds concerned in this investigation constituted themselves a small cooperative dairy company, and that, an accordance with the usual procedure, nil returns were pooled, and a standard payment made per pound of butterfat. ' For the month of. September, 1926, the financial operations of this “company” for cheese alone would he made up as .follows: —

111. THE “FAT PLUS CASEIN” METHOD. This system requires the determination of the casein content of the milk, as veil as its butterfat test. The 1 two are. then added together, and the sum is used in the same way as the butterfat test- is to-day used alone, for the purpose of calculating payments. This test libs, not found favour because, there is no simple casein test, capabe of yieding accurate results, avaiable to dairymen. In spite of this disadvantage, however, the “fat plus casein” method has been given' a fantrial in New Zealand, and has been abandoned because the results secured by it were so little different from the straight butterfat system that the extra time and labour involved were not being profitably expended. IV. THE “FAT PLUS CALCULATED CASEIN” METHOD. This aims at the same principle as the preceding one, hut seeks to obviate the necessity for a casein test by calculating the casein according to the standard formula (F—3) x .4 plus 2.1 where F equal percentage of butterfat. This is, in fact, the same in effect as the first two methods cited, and lias not established itself for a similar reason, namely, because it makes the largest

The above figures are a fair sample of the workings of the “straight but-ter-fat” system of payment when fat tests are relatively widely different. They show quite conclusively that, when extremes' of high and low-test-ing milk are paid for at a uniform rate per pound of interest, the high testing suppliers are paid more than their milk is worth, and that, in consequence, the producers of low testing milk are penalised to quite a considerable extent.

proportionate increase to the supplier with the lowest butterfat test, end thus places a premium upon the practice of robbing one’s fellow suppliers by watering one’s milk.

Impossibility of Finding Exact " Method.

Finally, it must, Pe said in connection with all these modifications that not one is exact, and that their best claim is that they are somewhat nearer to doing justice to high and low testing supplier alike than is the straight , butterfat system. Of course it must be said in extenuation that no uniform system of figuring payments for cheese milk could be absolutely exact in a wide variety of cases, and that perfect justice could only be done by preserving the identity of each supplier’s cheese, selling it separately, and giving him his own net proceeds. Such a proposal is absurd and utterly imposl- - in modern large-scale manufacturing of dairy produce, and we are. therefore forced to accept any system which most nearly does justice to the great bulk of suppliers. Such a system is the straight butterfat method when the milk is all from one breed of cow, and when butterfat tests are all within 0.5 per cent of one another; but, when tests are 1 per cent or more different, and when milk from different breeds is received, the low testing suppliers are invariably paid less, and the high testing suppliers more, than their milk actually earns. The present investigation has shown that normal low testing milk is capsi hie of returning to the producer at least 2d per pound butterfat more than high testing when used for cheesemaking. Under the present straight butterfat system of payment, however, very little inducement is offered to the Jersey owner to change over to a lower testing breed, because lie will receive no extra payment for his butterfat after the change. He may, of course, change over, and comfort 'himself by the reflection that his low testing milk will now earn more for the factory and that he, as a supplier, will participate in a fraction of this benefit, but be may be somewhat annoyed to think that his neighbour, who refused to change from high testing cows, will participate equally in the benefit which he did not earn. ft is therefore obvious that some system of payment must be devised in order to offer a direct inducement to dairy farmers to change over to low testing breeds of cows for cheese-making. If this is not done, there will always be a large proportion of high testing herd owners who will, under the existing system, continue to receive more than their just dues. As an indication of tho extent to which all previous proposals for the modification of the straight butterfat system of payment have remedied the injustice done to the low testing supplier and reduced the unfair advantage given to the high testing producer, a table has been prepared showing the percentage variation from the actual realisations which results from applying the methods l already cited, to the production and actual values of tho cheese produced from the milks of the three breeds in the present investigation during the month of September, 1926.

This weakness of the butter fat system when dealing with extremes of test has been recognised for many years, and numerous endeavours have been made to devise systems of payment which would more nearly do justice alike to suppliers of low and high testing milks for cheesemaking. It has already been demonstrated in this investigation that the reason for the greater earning capacity of normal low testing milk per unit of butterfat is that each pound of butterfat derived from Friesian or Ayrshire milk is associated with a greater weight of casein than a similar unit of butterfat derived from Jersey milk, and that this greater proportion of casein increases not only the actual weight of ■the cheese, hut also its moisture-carry-ing capacity, thus resulting in a greater yield of cheese per pound' of butterfat. The various modifications which have so far been proposed, all aim at making some addition to the figures for the butterfat, with the idea, of making allowance for the casein, and thus compensating tho lower testing •varieties for their increased content of this substance.

The four most important modifications of the butterfat system so far proposed are as follows: I. THE “FAT PLUS SIX-TENTHS’ ’ METHOD, which makes* a- constant addition of 0.6 per cent to every supplier’s butterfat test before proceeding with the usual calculations for total butterfat. pay-out per pound, and income. Such a constant addition is a larger proportionate increase to the mail with the lower test, and thus jhe gains more measure of compensation for the greater yielding capacity of his milk i'p" pound of butterfat. IT. THE “FAT PLUS TWO” METHOD, which is‘similar in principle to th« above, extent that 2.0 per cent is added to the fat tost of every supplier before calculating dividends.

Both of the above are nearer to performing justice than the. Straight Bntterfat method when dealing with extremes of test, but neither method has consistently found favour or beeome permanently established, for the reason that hoth offer a premium onon watering of the milk. If a supplier lowers bis test Try the addition of water, he gains a greater proportionate advantage by the constant addition of 0.0 per cent or 2.0 per cent to the figure, and thus gains directly at the expense of liis fellow suppliers by the adulteration. In fact, a Jersey supplier who watered his milk until the butterfat test was equal to that of a Friesian, would he paid at the same rate, although the difference between the earning capacities of the normal high yielding low testing milk and the adulterated low yielding milk and water would be. tremendous.

It will be at otiioo observed that the various modified .systems of payment have, at least in the two extreme cases perpetuated the old injustices, hut have reduced them to some extent. Nevertlia less, the extent of the reduction is not satisfactory, and a considerable measure of injustice is still being meted out to. the extreme low testing breed. Am important observation is that the Ayrshire, whiiidb lies more cir less midway in test between the other two, is given its correct payment to less than 1. pier cent, of error by ailili methods including even the straight butterfat system. This serves to emphasise the point already well known, that the butterfat method of payment is as fair as man can devise for the large majority of the cases which lie within a few “points”, of the cheese factory’s average test, and that a modification is desirable only for those cases which lie widely separated at either extreme, about 0.5 above or below the average. To avoid misapprehension regarding the above 'Statements, it must be pointed out that payments for Ayrshire milkwill not invariably be correct by all methods, and that they are more or less exact in the above instances only because the Ayrshire “test”, is approximately midway between the other two. On the other hand, a single Ayrshire supplier amongst a number of Jersey 'suppliers would be: penalised quite considerably by. any uniform method of payment.

A Proposed Modification of the Butterfat System of Paying for Milk for Cheese-making. In ido.nskler.ing the results of the present investigation, it was noted, that the production of cheese, and the nett realisations for each variety of milk were much more nearly proportional to the percentage of casein than to the percentage o.f butterfat. Hence it appeared that a system of pay-out based upon the percentage of casein would be more nearly fair t'ha.n any other. The following example will illustrate the results for the month of September, imagining such a system to be put into 'operation: —■

If these results are compared with those shown in the first table for all other systems of payment for milk for oheesemakiing, it will be observed that the method of payment foa- casein alone most nearly does justice to the supplier of both high and low testing milk, and is infinitely fairer than the present method of paying for butterfat alone. It is recognised, of course, that a method of paying for eheesemaking milk by casein alone would defeat itself and would result in chaos to the cheese industry /because it would pay equally, well for skim-milk and whole milk, and j would place a considerable premium | upon skimming. Moreover, from the| purely scientific point of view, the system would be just as unsound as the butterfat method alone, because each ignores the existence of an essential portion of cheese. I

We are therefore driven to the conclusion that the only method "which has any real chance of getting near to justice will he one which takes cognisance of both .the butter-fat and the casein in the proportions in which they actually influence the yielding capacity of the cheese-making milk.

Fromi the lade of success obtained by those methods of payment which depend upon the butterfat alone, it becomes apparent that a real advance can be secured only iby the addition of a casein test. Many will at once reply that this is impracticable under present conditions. It would hardly be feasible to suggest, for example, that the needs of Taranaki in casein testing could 'be met iby tlhe laboratory already established at Haw-era, as difficulties in regard to transport, and to the huge volume of work occurring at the same period eaoh month would be well nigh insuperable.

By comparing these results with those already given for all other methods of payment, it will be observed that the “casein/fat ’ method is much hearer to doing justice than any scheme so far proposed, and in particular, is infinitely fairer to all parties than the straight butterfat system at present in vogue.

It is considered, however, that casein testing could easily be introduced into factories for a very small capital outlay, and that it could be performed by any ordinary worker, once he had been given a little instruction and provided with the necessary apparatus and chemicals. Moreover it is neither logical nor just to refuse to achieve efficiency and to make correct and just payments merely because a little extra trouble and capital outlay are involved in this advance.

I Those with a mathematical inclination | will observe that the above “casein/ fat” method is mathematically equivalent to paying on casein alone, but the system of figuring aisi proposed, presents Uie following advantages: 1. By maintaining the butterfat test, no .radical and revolutionary departure is made from the present well established system of b.uttenfat testing, and a return to the straight butterfat method would be possible, as soon as the proposed casein/fat modification had served its purpose., 2. By keeping to the fore the production of butterfat, the importance of this essential constituent of choose will continue to bo recognised. 3. By a .regular system of butterfat testing a constant check will be kept upon the tendency which might otherwise occur to part-skim the milk. If tills tendency were observed by the analyst making the fat and casein tests, lie could at once adjust the numerical value of the ratio of casein to fat returned by him, and thus allow no advantage to the supplier. 4. The percentages of butterfat and casein would be lowered by watering, and the .ratio of one to the other would remain unaltered. Thus there would be no premium placed upon the practice of watering. 5. A very slight measure of advantage, amounting to less than 2 per cent., and often to less than 1 per cent., is paid to the low testing supplier at the expense of the high testing. This would serve to make some -amends for the very good “innings” which the high testers have enjoyed for many years, and, at the same time would provide that inducement, which this investigation proves is in the financial interests of the producer of eheesemaking milk —namely to adopt lower testing breed si of cows.

Proposed New Method. The new method proposed for the. payment for milk for cheesemaking is as follows: The butterfat test as .applied exactly as usual, and the production of butterfat computed just as at present. However, instead of paying out on this weight of butterfat, the figure is modified by multiplying by the ratio of casein to fa.it occurring in the period sample of oheesema.kLng milk. The weight so obtained may be called the “production in pounds of casein,/fat” and i® used for calculating payments in just the- same way as the production iu pounds of butterfat is used to-day. The example furnished by the month of September in the present investigation will make the scheme clear:—■

6. The proposed “casein/fat method” of payment, which involves a multiplication by the ratio of casein to- fat, has a certain amount of solid foundation in fact, and is not purely empyricall. Eeasons in Support of Change. It is not considered that the proposed “casein /fat” method of payment is capable of performing perfect justice in the matter of payment for milk for ciheesemakiing, but its use is advocated at present in New Zealand and especially in Taranaki, for the following reasons :

1. It is much more just and fair in its distribution of payments between the extremes of high and law test than the straight butterfat system. 2. It transfers a slight measure of advantage toj the law testing breeds and tbus offers an additional inducement to tlieir adoption.

■ The application of the principle to the whole period of the present investigation is shown in a further table together with the numerical comparison between it and tilie straight butterfat and the “Fat plus Two”, method. The casein / fat ratio method is seen to be much nearer the truth than the straight butterfat method, and to have secured the greatest measure of exactness an the important spring and summer months- when the casein ratio' of the milk is relatively high and thus when yields and payments to the. suppliers are greatest. During these months a moderate percentage divergence from the true pay-out means a largo sum to a large supplier. From January onwards, the method does not appear to !b.e quite so exact (although it stiill continues to be nearer than the butterfat alone), but it will be remembered that divergences will not now make such an important difference in actual cash, since, yields and dividends are steadily declining. Over the whole season, the casein / fat method of payment is slightly nearer the truth than the “Fat plus 2” method but it shows this important difference that, whereas tlie ‘Fat plus 2” system perpetuates the old injustice to the low tester and the unfair advantage to the low tester, the casein /fat method reverses the. position and teiids to offer some atonement for past injustice. Only a Temporary Measure.

One final word must 'be said before closing the discussion upon methods of payment for cheesemaking milk. It must not tie supposed that this report attacks the fundamental principle of the Babcock test, or asserts that all payments for cheese-making milk by butter-fat alone are unsatisfactory and unjust. Actually the but-ter-fat test is extremely satisfactory for the large majority of the average cases which lie closely grouped around the mean test of a cheese factory, and would be quite satisfactory and fair to all parties if the same breed of milk, whether high or low testing, were involved; but it does not make a fair distribution between extremes

of high and low test when both supply the same factory. This is its chief, and perhaps its only, fault. For this reason the casein/fat ratio method of payment is advocated only as a temporary measure in order to stimulate the tendency to adopt low testing breeds of cows for cheesemaking. After the change had become general, the unmodified butterfat system of payment could once more be applied universally. An Alternative System.

It is l recognised that the proposed casein/ fat system of payment would, involve a number of drastic alterations in dairy office returns, and might prove impracticable for reasons at present unforseen connected with factory management. Ibe ends required, however, might still be served by an alternative proposal which. also might not disturb the present system of factory millk testing or pay-out. This alternative system is based upon a scheme of penalties and compensations according to whether a supplier’s milk tested above or below the factory average during each period. It is proposed to mention the alternative system here and to point out that it is possible from data which might be obtained over a number of seasons from different factories, to assess some measure of percentage penalty or campenation for every “point” in test above or below the factory average for the period. The extent of these penalties nr compensations would necessarily varyaccording to the special circumstances obtaining in individual factories, and lor this reason, attention will merely be drawn here to the possibility of applying such a system.

SUMMARY OF RESULTS OF INVESTIGATION.

In stating the aims and objects of the investigation at the beginning of this report, a number of questions were formulated concerning which answers were sought. It will now be appropriate to revert to these questions, and to answer them as briefly as possible, with little or no reference to the facts and arguments which have led to the conclusions. (1) Statistical Matter relating to Cheese-making in New Zealand. Statistics are presented, either in the body of the report, or in the appendix, showing over a whole season, typical New Zealand results for the following : 1. Percentages of fat, casein, total solids, and solids-not-fac of tlie milks ql‘ tliree breeds of cattle. 2. Gross yields of cheese per pound of butterfat obtainable from such milks. 3. Losses-of fat, casein, and total solids occurring in the whey from three varieties of milk. 4. Percentages of moisture, fat andi proteins occurring in different varieties of cheese. 5. Shrinkages of" different types of cheese during curing, and afterwards, during the voyage to England.

(2) What is the chemical analysis of the type of cheese which hest suits the export trade for which New Zealand caters and from what type of milk is it derived? Plenty of toleration is exhibited towards very diverse types of cheese, but in general, a truly white (if uncoloured) cheese showing about — Moisture 37 per cent. Fat 1... 32 per cent. Proteins 24 per cent. 1 Fat in water-free . substance' ... 50. S per cent, will give every satisfaction, provided that it is clean in flavour, “meaty”, in body, and close and smooth ift texture. Sudhi a cheese would be made from mi Ik containing from about 3.7 per cent, to 3.9 per cent of butterfat.

(3) Can cheese of varying fat or moisture percentage he readily distinguished by physical examination? Provided, that variations are not extreme in magnitude, minor fluctuations around the’mean composition of normal Cheese cannot Ibe detected with certainty by physical examination alone. Moreover errors in manufacture may produce abnormalities in body and. texture which will completely mask the normal effects 1 of a certain fat or moisture content. (4) Is the present New Zealand minimum standard of 50 per cent, of fat in the water-free substance of cheese entirely satisfactory to our buyers and entirely in our interests .?. This regulation, which at present demands a minimum of 50 per cent, in the lowest testing portion of the season operates in such a way as to require New Zealand' cheese factories to export in the autumn months large quantities of cheese which considerably exceed the minimum fat. requirements. Much of this Cheese is greasy and unsatisfactory to the trade, and is therefore an economic waste from the producer’s viewpoint. (5) Does cheese having substantially more than 50 per cent, of fat in the dry matter carry any premium over less fatty varieties ?

Well-made dbeese possessing from. 49 to 51 per cent, of fat in the dry matter is apparently quite satisfactory to the trade in its fat content, and full market prices will be given .if the body and ..texture -are good. From 51 to. 52 per cent, comments indicate that the cheese is noticeably fat and entirely satisfies every requirement. Cheese possessing from 52 to 56 per cent, of fat in the dry matter is tolerated, but it cannot consistently command any premium. Lf over 56 per cent, it becomes greasy, and is actually lowered in value. (6) Is this premium, if any, sufficient to compensate for the lower yield of cheese per pound of butter-fat derived from high testing milk ? Nio. Low testing milk, capable of yielding 10 per cent, or more cheese per pound of butterfa.t than high testing, can, with proper attention to manufacture, be made up into, cheese capable of realising fullest market prices. Producers of milk for oheesemaking are de-

priving themselves of l£d to 2d per pound butterfiat by their present adherence to high testing cows. (7) Can any variation from the straight butter-fat basis of payment vfor milk for cheese-making be devised in order to compensate the lower testing supplier for the increased yield of cheese per pound of but-ter-fat derived from his milk ? Two methods are possible : (1). By employing the ratio, of casein to. fat occurring .in the milk, but it is proposed only as ia temporary measure, in order''to accelerate a change over to low. testing cows, after which, the straight butt erf at system could once

TABLE A. [Realisations for Cheese Butterfat produced Friesian £177 3 11 2164.8 libs Payout per pound of Ayrshire 65 11 8 843.S lbs butterfat-—18.5207-d. Jersev 115 1 61 1628.3 lbs (ISTo' allowance made for whey — butterfat oi • for costs of £357 16 4 4636.9 lbs manufacture.) Incomes ■paid to three suppliers:— Friesian 2164.S x 18.5207d ==t £107 1 0 = £10 2 14 or 5.7% * underpaid. Ayrshire S43.S : x 18.5207d =i £05. O 3 — 9 5 or 0.7% underpaid. Jersey 1628.3 : x 18.5207d =/ £125 13 1 = £10 11 61 or 9,2% overpaid. £357 16 4

1 TABLE B. - APPLICATION OF VARIOUS METHODS OF PAYMENT FOR THE MONTH OF SEPTEMBER. Straight Fat t 2 Fat t G-10th Fat t Fat i Average Butter-fat Casein 'Calculated Fat Test Casein for month Friesian — 5.7% - 2.5% — 4.4% — 3.3% - 4.4% 3.472% Ayrshi re - 0.7% - 0.2% - 0.5% t 0.02% - 0.4% 3.756% Jersey ' t 9.2% t 3.9% t 7.1% t 5.0%' t 0.9% 4.430% - = underpaid 1 ==• overpaid

Pries ian TABLE 0. 02,350. 2.40 .1400.42 £077 3s 14 d Ayrshire 22,402 2.4.0 557.81 £05' 10s 30,707 2.00 054,38 £115 Is Sd Jersey 64 d 3008.01 £357 10s 4d Payout per Ob of Casein = 28.5433d. Pries ian INCOMES ON THIS BASIS: 1490.4 x 28.5422 = £177 10 4 = 10/24 or 0.4% Ayrsh ire overpaid 557.8 x 2S.5433 — £00 0 10 = 15/2 or 0.1% Jersey \ overpaid 054.4 x 28.5433 = £013 10 2 = £1 11 44- or 0.4% underpaid

TABLE T>. Production of Patio of Production of Pealisations Bui tor-fa t (Casein to Casein/fat from cheese Fat in milk Friesian 2104.8 0.092 2104.8 x .092 = 149S.041b £177 3 14 Ayrshire 843.8 o.oot 84 3.8 x .004 — 500.281b £05 1 1 8 Jersey t (128.3 0.587 1028:3 x .587 = 955.811b £115 1 04 3014.131b £357 10 4 Payout, per lb of Casein/fat = = :2S.4914d. INCOME'S ON THIS EASES: Friesian 1498.0 :x : 28.4914 = £17(7 10 9 =•. 13/7-1 or 0.4% overpaid Ayrshire 5GO.3 x : 28.4914 ; = £00 10 3 II CO o overpaid Jersey 955.8 : c 28.4914 — : £113 9 4 =i £1 12 24 or 1.4% underpaid