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THE question could well be asked as to why load controlled high strain fatigue tests should be performed, particularly when so much of the current research employs strain control? The answer is simple: a load controlled high strain fatigue environment was discovered, and a test programme subsequently initiated to provide data that could be applied to future designs. Besides, what more realistic way of testing is there? Fundamentally, most structures, or elements thereof, sense load only during a working life; strain is merely a resulting effect.

Generally speaking a “new” loaf is demanded and the baker who cannot deliver “new” loaves loses trade. But what is a “new” loaf? From the point of view of the chemist this question has formed the subject of innumerable investigations. A definition of a “new” loaf demands an understanding of “staleness” and the staling of bakery products is a subject of great complexity. The old idea was that it was entirely a question of the “drying out” of the bread, but cereal chemistry has proved that such a solution, namely the prevention of “drying out,” is only of partial efficacy; in fact “staleness” is caused by a change in the starch of the flour which is inherent in it and cannot be prevented by precautions which maintain the moisture content at a certain figure. The investigation of this type of staling has occupied the attention of many famous chemists, but the full explanation has not yet been obtained. Mass production has demanded many studies in that aspect of science known as “physical chemistry.” An example can be found in the preparation of certain sauces. Those of you who have made mayonnaise sauce know that to beat the olive oil into the mixture is fraught with difficulties. By means of the fork, used as a beater, the oil is distributed in very small particles through the mass of liquid, so that every globule of oil is separated from every other one. If the action docs not proceed properly the system breaks down and the mayonnaise “turns” and is spoiled. The manufacturer has to prevent this “turning,” not in a few pints but in hundreds of gallons. It is the chemist who has enabled him to do this and to manufacture with success those scores of salad‐dressings which are so delectable and the purchase of which relieves the housewife of so many hours of work and so much arm‐ache. An example of some interest is concerned with smoked salmon, which normally is a very variable product, whether it be the highly salted variety of the northern climes or the much less salted kind which has found favour in this country. The production of a lightly salted product is far more difficult than the more salted variety because much smaller changes in salt content become more noticeable. These small differences are so obvious to the confirmed smoked salmon eater that he detects not only the differences between one grade and another, but also the differences of salt content that occur in different parts of the same side of fish. It has fallen to the chemist so to change the methods of production of the lightly flavoured variety that the distribution of salt through the fish is even and the flavour therefore constant. This study of smoked salmon is only an example of the very big problem of standardisation, standardisation demanded by the consumer—and it follows that the big manufacturer must produce goods of standard flavour and appearance. Science steps in and gives the manufacturer those controls which enable him to produce, day in and day out, that standard range of article, whether it be ice‐cream or toad‐in‐the‐hole, Worcester sauce or cheese cakes, roast beef or jelly crystals. Modern science has introduced a new factor into our conception of what food should be. In the past it was only necessary to ensure that food should be “pure and wholesome,” by which was meant—in general terms—digestible and without any harmful constituents, be they natural or adventitious, bacterial or otherwise. So long as food complied with this broad definition everyone was satisfied. But biochemists and physiologists have demonstrated the importance of other factors, salts and vitamins, and it is necessary to consider the new situation thus created because it may be that the treatment of food to retain those substances may make it necessary to change preconceived notions. It may be that “palatability” may be affected, palatability which includes taste and appearance and odour. The whole subject is so complicated and, notwithstanding the enormous amount of work carried out, so little understood that no one as yet can be dogmatic, no one can state what are the optimum amounts of vitamins required by ordinary persons to keep them in good health. Having, however, decided the amount required, are we to try to preserve such quantities as occur naturally, or are we to fortify the food which we cat by added synthetic or even by purified natural vitamins? A further important consideration is whether the degree of maturity of, say, fruit in relation to maximum vitamin content coincides with optimum palatabilty. Certain it is that information gradually being accumulated on the importance—in many cases vital importance—of the minor constituents of foodstuffs leads to the conclusion that, to ensure the presence of all valuable minor constituents—be they known or unknown—the foodstuffs must, as articles of diet, be ingested almost in their entirety. This is probably an extreme view, for, in many cases, the result would be a product of reduced palatability or appearance, or, what is probably more important, “different,” and people do not like their food to be abnormal, i.e., to differ from their preconceived notion of what it should be. Nevertheless an “improvement” in the method of production, put into practice by the food manufacturer with the best intentions, may possibly result in a lowering of the dietetic value of the food, as, for example, by mechanical removal of an important part (the classical example being polished rice), by heat treatment, by oxidation or by materials added during cooking. The minor metallic constituents of food are gradually being revealed in their true importance. Copper, zinc, and iron are now known to be of importance. It is probable that every baby is born poor in calcium but rich in iron; milk, the natural food of the infant, is rich in calcium. It is only in the last few years that it has been shown that green vegetables as usually cooked are of very little real value. Cooking green vegetables in water containing sodium carbonate results in the almost complete destruction of the Vitamin C, and the discarding of the water removes the extracted salts. A green product certainly results but of greatly reduced nutritional value. On the other hand, it would appear that little destruction of vitamin activity takes place when the canning of vegetables or fruits is properly controlled. Sherman has said that attention to mineral salts and vitamins will lead to “buoyant” as distinguished from merely “passable” health. It is obvious that education of the public is essential if an intelligent use is to be made of the knowledge being gained by chemists and allied scientists. It is a most important fact that methods are being developed to assay foods for vitamins by chemical means. Biological feeding tests are obviously unsuitable for control purposes but, as the chemical identity of the vitamins becomes more clarified, chemical tests will become available for their determination. It is obviously the duty of the medical services of the country to guide the public as far as is possible on questions of nutrition. When such guidance becomes effective, the food producer will not be slow to see that his goods are up to the standard necessary, adding one more burden to the already loaded back of the chemist concerned with food production.

The question whether grape juice may or may not be preserved with sulphur dioxide is one which arises occasionally as a result of a certain ambiguity in the wording of the First Schedule of the Regulations. It is not a matter of opinion, as some would hold, but a matter of law, and, as such, should be fully appreciated by the legal advisers of local authorities, if not by Public Analysts. Item 4 of the First Schedule of the Regulations states that “Unfermented grape juice and non‐alcoholic wine made from such grape juice if labelled in accordance with the rule contained in the Second Schedule to these Regulations” may contain 2,000 parts of benzoic acid per million of grape juice and does not admit of the presence of the addition of any sulphur dioxide. The Second Schedule prescribes that, if the proportion of benzoic acid present in grape juice exceeds 600 parts per million, it shall be labelled with a declaration to that effect and also with the words “and is not intended for use as a beverage.” Item 5 of the First Schedule of the Regulations states that “Other non‐alcoholic wines, cordials and fruit juices, sweetened or unsweetened” may contain either 350 parts of sulphur dioxide per million parts of preparation or 600 parts per million of benzoic acid. Normally one would infer from this that grape juice to be used as a beverage falls under Item 5 of the Regulations, but that, if for some special reason it is not to be so used, it is permitted to contain up to 2,000 parts per million of benzoic acid provided that it is labelled to the effect that it is not to be used as a beverage. It should be noted that Item 4 does not read that grape juice and non‐alcoholic wine made from it may contain 600 parts per million of benzoic acid, but that, if labelled in accordance with the rules contained in the Second Schedule, it may contain 2,000 parts of this preservative. If grape juice were only allowed to contain benzoic acid as a preservative and if sulphur dioxide were prohibited under all circumstances one would have thought that Item 4 of the First Schedule would have been drawn up to indicate this, but no such indication is given at all. At the time that the Preservatives Regulations were issued it was fully recognised that sulphur dioxide was employed as a preservative in grape must. Whilst the Departmental Committee was considering the matter of preservatives and colouring matters the Ministry of Health issued a Report on Public Health Subjects, No. 24, entitled “Report on the Composition of Commoner British Wines and Cordials (Alcoholic and Non‐alcoholic),” by Dr. G. C. Hancock, C.B.E., one of the Medical Officers of the Ministry, together with a Report by the Government Chemist on the Examination of Samples. In the introduction Dr. G. Newman, the Chief Medical Officer to the Minister of Health, writes : “The most important of these materials are preservatives, and Dr. Hancock mentions the considerations which underlie the use of these substances in the manufacture of British wines and cordials. As, however, the question of preservatives and colouring matters in foods is being considered by a Departmental Committee of the Ministry he has made no specific recommendations relating to the use of these substances.” On page 4 at the end of the sixth paragraph Dr. Hancock refers to grape juice or must and says : “It is sent here in a highly concentrated form and is usually ‘sulphured,’ i.e., treated with sulphur dioxide in order to inhibit fermentation during transit.” Among other information placed at the disposal of the Departmental Committee was Dr. Hancock's report and in the Final Report of the Committee, also issued in 1924, paragraph 57 states: “Sulphurous acid and sulphites are extensively used in beer and alcoholic wines, to some smaller extent in non‐alcoholic beverages, and in preserving fruits and fruit juices, dried fruits, gelatine and sausages. … In the case of beer, wines, fruit and fruit juices the introduction comes partly from the treatment of the vessels of preparation and storage, partly from the materials used and partly from the actual addition of preservative in the course of manufacture or treatment for storage.” When considering the question of alcoholic wines, Foreign and British in detail, the Committee stated their opinion in the following words (para. 144): “Foreign and British wines are by no means closely related products. The former are the naturally fermented produce of the grape, while the latter are rarely derived from fresh fruit and are far more commonly prepared from a basis of dried fruits, rhubarb or imported grape must, fermented after the addition of sugar and flavouring materials, such as dried ginger‐root, orange peel, alcoholic essences or foreign wines. Considered from the point of view of preservatives, however, they have two features in common, (a) that the alcoholic content is very similar in each, (b) that sulphur dioxide is the preservative which is usually favoured (in addition to the alcohol present) to prevent secondary and other undesirable fermentations and sourness.” Instead of making any suggestion that the use of sulphur dioxide should be prohibited in grape must, the Committee draw their conclusion in paragraph 147 in the following words : “Our conclusion is that while in general preservatives should be unnecessary in alcoholic wines of ordinary strength, there may be circumstances which render the entire elimination of preservatives impracticable for the present. We think, however, that no other preservatives than sulphur dioxide should be permitted, and that this substance should not be present in amounts exceeding 3 grains of sulphur dioxide free and combined per pint (343 milligrams per litre).” This recommendation was adopted in the Draft Statutory Order issued in February, 1925, but, when the final Order was published, the quantity of sulphur dioxide permitted had been increased to 450 parts per million, making the law in this country agree with that already adopted in France. The recommendation made by the Departmental Committee was put forward after the Committee had commented on the fact that British wines are largely prepared from “imported grape must.” It seems remarkable that the Committee should have expressed the opinion that sulphur dioxide is used for sulphuring the casks, that sulphur dioxide is permitted in the completed wine, if it is not allowed to be present at intermediate stages, and that a Regulation was made by which benzoic acid only could be present in the unfermented grape juice, if this is not permitted to be present in the fermented alcoholic wine. When benzoic acid has once been added it cannot be eliminated and, as recognised by the Departmental Committee, benzoic acid is undesirable from the fermentation aspect. Had there been any intention to prohibit the presence of sulphur dioxide in unfermented grape juice, the Regulations would have rung the death‐knell to the manufacture of British wines, which have been produced in increasing volume during the last twenty years. Further, if there had been any intention to prohibit the addition of sulphur dioxide to grape juice, one cannot but express surprise that the importation of such juice has not been suppressed long ago by the Customs Authorities, since Section 8 (1) of the Regulations lays the responsibility for the control of Imported Articles of Food on the Officers of Customs and Excise and, through them, on the Government Chemist. The failure of the Government Chemist to condemn grape must containing sulphur dioxide cannot be due to his ignorance of its presence because the chemical analyses for Dr. Hancock's Report were carried out by the Government Chemist, and on page 58 of the Report No. 24, to which reference has already been made, analyses are given of two French musts containing 360 and 302 parts of sulphur dioxide per million respectively and of an American concentrated must containing 63 parts of sulphur dioxide per million. If we now look at paragraph 153 of the Final Report of the Departmental Committee we find that the matter of preservatives in certain non‐alcoholic beverages is dealt with in the following words: “We consider that sweetened and unsweetened fruit juices, syrups, cordials, non‐alcoholic wines and articles of similar composition such as certain well‐known proprietary cordials, are peculiarly liable to develop moulds and to ferment, owing to liability to exposure on the consumer's premises between the first opening and final consumption, and we think that on this account they may under present trade conditions need the addition of a small proportion of preservative. We therefore suggest that the presence either of benzoic acid up to 5 grains or of sulphur dioxide up to 3 grains per pint might be considered.” These recommendations were adopted in the Draft Rule and Order, issued in February, 1925, and there was no reference in this Draft indicating that grape juice was to be treated in any manner distinct from other fruit juices. The introduction of Item 4 in S.R. & O. 1925, 775, came as a complete surprise to everyone and the general surprise felt was mentioned by Mr. C. A. Mitchell (now Dr. Mitchell) in a paper read before the Medico‐Legal Society on Tuesday, April 20th, 1926, with the Rt. Hon. Lord Justice Aitken in the chair. Mr. Mitchell made the following statement: “The fourth item in the Schedule is one at which one can only stare and wonder how it ever came there. According to this regulation unfermented grape juice and non‐alcoholic wine made from it, may contain the enormous quantity of 17 grains of benzoic acid per pint, provided that it is labelled in accordance with Schedule II. I am fairly familiar with the cases which have been brought into Court during the last 20 years, but I cannot recall an instance of a non‐alcoholic wine (labelled or unlabelled) containing an amount of preservative equivalent to this quantity of benzoic acid.” Mr. Mitchell then proceeds to explain that the most probable reason for the introduction of this item into the rule is that it is intended to apply to non‐alcoholic sacramental wine, which is not to be used as a beverage, but which is taken a little at a time and is expected to keep for long periods, when the bottle has once been opened. This is, in fact, the position so far as I am aware and there was never any intention of any restriction on the use of sulphur dioxide in the ordinary way as a preservative in unfermented grape juice so long as the amount present did not exceed 350 parts per million.

The President of the Board of Agriculture has introduced in the House of Commons his long‐promised Bill for preventing the sale of butter containing large amounts of water, and the proposed measure appears to have been received with general approval on both sides of the House.

The annual report of the Food Investigation Board which has just been issued contains much information relating to the cold storage of meat which is of interest. The Engineering Committee has offered some valuable suggestions on the means of improving refrigerating plant. Particular attention has been given to the condition known as “Black Spot,” which is caused by a fungus and develops in cold stores. This hardy fungus will grow at 5 deg. Cent. below freezing point. It is possible that even this temperature may not represent the lowest at which growth can take place. Spores—or seeds—of this fungus retain their vitality for six months under cold storage conditions, after which they are still able to develop normally at ordinary temperature. There was much “Black Spot” on meat coming from the Southern hemisphere during 1918–1919. It has been ascertained that this was due to the prolonged cold storage necessitated in 1917–1918 by the war. As conditions become more normal the duration of storage will be so short as to prevent the development of the pest. On the other hand, it is known now that fluctuations of temperature are dangerous, because the fungus flourishes best at 0deg. Cent., and also because fluctuations alter the humidity of the cold store and cause snow to fall. The flakes of the snow carry the fungus into the meat. The fungus is thought to come from the stock yards and slaughter‐houses. It is not, however, so far as is known, poisonous to human beings and produces no poison in the meat. Meat so affected need not, it is thought, be condemned as unfit for food unless putrefaction is also present. The fruit and vegetable committee is now investigating the storage of English apples. This is a complicated problem involving questions of humidity, temperature, time, soil, and packing. The results obtained so far suggest that a temperature of 1 deg. Cent., is better than higher temperatures. With a humidity of 85 per cent. saturation at 1 deg. Cent. or 3 deg. Cent. no shrinkage of the apples has been observed. Marked shrinkage occurred with a humidity of 60 per cent. saturation at 5 deg. Cent.

Mr. H H. Bagnall, B.Sc., F.I.C., Public Analyst for the City of Birmingham, comments in his annual report on the work done at the City laboratory and on the still apparent need for standards and definitions of food, and of legislation to enforce their application in manufacture or in shops. Of the 5,472 samples taken in the city under the Sale of Food and Drugs Acts 4 per cent. were found to be adulterated, but he observes that misdescription of articles of food is much more common than actual adulteration. The number of samples taken during the year was larger, and the variety greater, than in any previous year. About 140 different varieties of foods and drugs were examined, and few, if any, foods were not sampled. It was reassuring to learn that the Minister of Health was considering the introduction of legislation on the lines of the recommendations submitted in 1934 by the Departmental Committee which enquired into the working of the law as to the composition and description of articles of food other than milk. Ice‐cream was a case in point. In fifty‐one samples taken, the fat content varied between less than 2 per cent. and 19 per cent. Roughly, the samples were of two classes. Those containing less than 4 per cent. were bought mainly from carts in the streets of parks, and were probably the products of smaller makers; those with more than 8 per cent. were manufactured on a large scale by a few well‐known firms. “It is obvious something is wrong here,” Mr. Bagnall reports. “Apart from any question of price, ice cream is, or should be, a valuable article of food, and the purchaser should have some means of knowing what to expect when he asks for it. At the moment he may get a substance which approximates to frozen custard (not made with eggs !) or he may get a really first‐class product containing a considerable amount of cream. The position is similar with respect to a number of other products, particularly compounded articles; and the beneficial effect of legislation in such matters is clearly shown in the case of condensed and dried milks. This kind of governmental interference with manufacture used to be thought of as grandmotherly legislation; but, when one remembers the sort of statement, bearing no relation to the contents, that used to appear on tins of condensed milk, one cannot but feel that there may be some virtue in these departures from laisser‐faire methods. At any rate, no one would wish to return to the old haphazard days when condensed milk was simply what the manufacturers chose to make it. It is curious that the law is far more careful that the composition of feeding stuffs sold for the use of cattle should be made known to the purchaser than that articles sold for human consumption should be sold under a guarantee of quality. If I buy, say, cotton cake for feeding cows, the vendor is bound to give me an invoice stating the amounts of oil, protein and fibre contained in it, and severe penalties are entailed if false statements are made. If I buy an infant's food, however, there is no compulsion on the part of the maker to give particulars regarding its composition. In fact, the label may contain statements entirely at variance with the analysis, but which, nevertheless, are of too vague a character to become the subjects of police court proceedings. It is surely as important that the mother of a child should know something of the composition of the food she uses as that a farmer should know the food value of his cattle cakes, and it is to be hoped that legislation on such matters may not be unduly delayed. The misdescription of articles of food is a much more common thing than adulteration. Under modern conditions of inspection and sampling, it simply does not pay manufacturers and retailers to risk the cruder forms of adulteration and substitution, but the wide use of advertising as an aid to sales, often leads to the use of exaggerated statements regarding the quality and food value of articles of diet. We are all familiar with the extraordinary claims put forward on behalf of particular foods of well‐known composition which seek to show that they possess unique properties not shared by other similar foods. It is often impossible for the food analyst to check such statements, and the public is deceived into thinking that a superior article is being obtained. Often it is only in the advertisements relating to the article in question that one finds these exaggerated statements, and when a tin or packet is bought it is found that the label gives a much milder description of the contents. Under the present law only statements appearing on the label can be made the subject of legal proceedings. It is desirable that false claims appearing in advertisements should also be brought within the scope of food and drug legislation.” During the year a number of samples of pasteurised milk were examined by the “phosphatase test.” Of 112 samples, fifty‐eight were efficiently pasteurised; in thirty‐six cases some technical error had occurred during the process, such as imperfect temperature or time control, or a small admission of raw milk; and in the remaining eighteen cases there was evidence of gross negligence. The samples were taken at selected times and places thought likely to yield abnormal figures, so that too much weight should not be given to the fact that about 48 per cent. of the samples did not pass the test.”

The Dominion of New Zealand is not, at present, an exporter of canned fruits. The canned fruits which are made are made for home consumption. So far as the export trade of fruit is concerned the New Zealand growers have mainly concerned themselves with raw apples and to a smaller extent with pears. Everyone knows that the Dominion extends over a small range of low southern latitude; that it has a sunny and equable climate; a rainfall well distributed over the year; a variety of excellent soils. It will, in a word, grow almost anything, a fact that has not altogether proved to be an unmixed blessing. Up to 1876 its hundred thousand square miles of area was divided into nine provinces; after that date by the Provinces Act, 1876, the country was divided for administrative purposes into counties with powers of local self‐government. The central government, at Wellington, is responsible for the Acts referred to in this article, these Acts being applicable to the whole of the Dominion. Such legislative measures as have been passed in relation to the fruit industry have for their main object the development of fruit orchards, chiefly those of apples at present. In the year 1930–1, 3,539 tons of fruit were used in the making of jams, jellies, canned or bottled fruits and “other products.” The value of the fruit canned or bottled was £45,763, as against £165,655 for jams and jellies, and £119,104 for “other products” in the same period. This works out roughly to about 14 per cent. The Orchard Tax Act† (No. 25, 1927) provides for special taxation for the development of the fruit‐growing industry and the protection of orchards from fireblight.‡ Under Section 3 of the Act any fruit grower with 120 or more trees in his orchard shall pay one shilling for every acre or part of an acre. The minimum yearly tax under this section shall be five shillings. The term “fruit” includes apples, pears, quinces, oranges, lemons, peaches, nectarines, apricots, plums and cherries, and any other kind of fruit which may subsequently be declared by the Governor‐General in the Gazette. This is a good list of fruits and illustrates as well as anything of the kind can the great possibilities of New Zealand as a fruit‐growing country. Lemons are an important crop in North Island. Much of the lemons consumed in New Zealand are home grown, but it is desired to make the Dominion self‐supporting in this respect. The Poorman Orange, according to the New Zealand Journal of Agriculture, is becoming popular as a substitute for imported grape fruit. Oranges it seems have been cultivated with success since about 1875, as well as citron, lime and lemon in the neighbourhood of Auckland. Thompson (Naturalisation of Animals and Plants in New Zealand, 1922) quotes a remark by an officer of the brig “Hawes” in December, 1928, that he saw a few orange trees that had been introduced with success. The same author remarks that apples, pears, and, according to Major Cruise (1820), peaches had been introduced by the missionaries. It was about this time that missionary enterprise, which would appear to have been somewhat badly needed, made its appearance.

It is seven years ago since I first took up the estimation of dirt in milk samples; there had been numerous complaints about dirty milk sold in Chester, and the Public Health Committee asked me if it would not be possible to estimate the dirt, so that proceedings could be taken against the milk sellers.

The number of investigations and investigators of vitamines seems to be increasing in geometric proportion, yet the sum total of our knowledge accumulates but little. The reason for this interest may be found in the unusual though well‐deserved concern aroused by the new light thrown on the all‐important problem of nutrition. Research has been stimulated as never before, and it is to be feared that workers have plunged ahead with great enthusiasm for the broader aspects of the subject and with but insufficient attention to the finer technical points. There is urgent need for more intensive and less extensive research if we are to arrive at a final understanding of the nature of the vitamines and their rôle in nutrition. A brief survey of the facts and a consideration of the present status of the subject may not be out of place.

In consequence of inadequate accommodation at our present address, the Editorial and Publishing Offices of the British Food Journal will be removed to more commodious offices at