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The purpose of this paper is to investigate fast pyrolysis of maple fruit as an energy sources. This could serve as a solution to the energy sources problem.

Fast pyrolysis of maple fruit (samara) was achieved in a fixed bed reactor. The pyrolysis experiments have been conducted on the sample of maple seeds to particularly determine the effects of pyrolysis temperature, particle size and sweep gas flow rate on the pyrolysis product yields.

The oil of maple fruit from fast pyrolysis has good properties to be a potential candidate as a biofuel or as a source of chemicals. In addition to being environmentally desirable, it can reduce the energy cost, e.g. that Turkey imports a majority of its energy.

The use of maple fruit for fast pyrolysis and pyrolysis conditions impact on the yields of pyrolysis liquid can be considered as novel aspects of this paper.

As a result of the changes caused by the preparation of foods gradually passing out of the home into the hands of manufacturers, there has arisen an absolute need for a complete supervision of the public food supplies. A supervision which shall place some limit upon the substitution of cheaper and inferior methods and dangerous materials in place of the standard formerly used in our homes.

The Departmental Committee appointed to inquire into the use of preservatives and colouring matters in the preservation and colouring of food, have now issued their report, and the large amount of evidence which is recorded therein will be found to be of the greatest interest to those concerned in striving to obtain a pure and unsophisticated food‐supply. It is of course much to be regretted that the Committee could not see their way to recommend the prohibition of all chemical preservatives in articles of food and drink; but, apart from this want of strength, they have made certain recommendations which, if they become law, will greatly improve the character of certain classes of food. It is satisfactory to note that formaldehyde and its preparations may be absolutely prohibited in foods and drinks; but, on the other hand, it is suggested that salicylic acid may be allowed in certain proportions in food, although in all cases its presence is to be declared. The entire prohibition of preservatives in milk would be a step in the right direction, although it is difficult to see why, in view of this recommendation, boric acid should be allowed to the extent of 0·25 per cent. in cream, more especially as by another recommendation all dietetic preparations intended for the use of invalids or infants are to be entirely free from preservative chemicals; but it will be a severe shock to tho3e traders who are in the habit of using these substances to be informed that they must declare the fact of the admixture by a label attached to the containing vessel. The use of boric acid and borax only is to be permitted in butter and margarine, in proportions not exceeding 0·5 per cent. expressed as boric acid, without notification. It is suggested that the use of salts of copper in the so‐called greening of vegetables should not be allowed, but upon this recommendation the members of the Committee were not unanimous, as in a note attached to the report one member states that he does not agree with the entire exclusion of added copper to food, for the strange reason that certain foods may naturally contain traces of copper. With equal truth it can be said that certain foods may naturally contain traces of arsenic. Is the addition of arsenic therefore to be permitted? The Committee are to be congratulated upon the result of their labours, and when these recommendations become law Great Britain may be regarded as having come a little more into line— although with some apparent reluctance—with those countries who regard the purity of their food‐supplies as a matter of national importance.

It is a well known fact that bacteria play a large part in the success or failure of the satisfactory production of dairy products, but the role of yeasts and moulds should not be overlooked. These living organisms, commonly known as fungi, are the next higher form of life in the vegetable world after the bacteria stage. Their form of growth resembles the growth of plants in that they reproduce by budding, and their spores, analogous to the seeds of plants, are the means whereby many species propagate further generations. The yeast cell is much larger than the ordinary bacterium, so that it is possible to study them with the aid of much lower magnifications. When grown on solid media the yeasts give colonies not unlike those of bacteria except that the edges of the colonies are less defined, the colonies themselves project well above the surface of the media, and their surfaces are usually of a rough appearance. A good example of mould growth is that of the ordinary “green mould.”—Yeasts usually prefer to grow on the surface of liquids, and moulds are found to grow most vigourously on solid or semi‐solid media, such as meat, cheese, butter, etc. The growth of bacteria in the media hinders the simultaneous growth of the fungi, so that it is only after the media has become too acid for the growth of bacteria that yeasts and moulds are able to grow. In support of this theory it has been found that fungi will grow on the surface of sterile milk, but ordinary fresh milk containing bacteria is not a suitable media as the fungi cannot compete with the bacteria. It is found, therefore, that only bacteria proliferate in fresh milk. However, when milk has become sour bacterial growth is arrested, and it is then that mould growth becomes perceptible. The fungi tolerate a relatively large amount of acid. Media used for their cultivation is generally standardised to a ph of about 4.5. The optimum temperature for their growth is in the region of 75°–90° F. Some species will grow at 32° F., others even below this temperature. Low temperatures are not lethal to the fungi, so that when infected products are removed from cold storage growth may occur. The temperatures required to kill them and their spores generally falls between 130°–180° F. Most yeasts are killed at temperatures above 120° F., while their spores may have to be exposed to higher temperatures.

A practical fisherman or fishmonger has no difficulty in recognising the different members of the cod family. To the layman (and most public analysts and inspectors of food and drugs are perhaps to be included in this category) the problem is less easy. But if a sample includes (or consists of) a thick sectional slice complete with skin, its identification will be assisted by reference to the following table. Special importance should be attached to the black and strongly marked lateral line of the haddock, and to the “specks” to be seen with the aid of a small lens, or even with the naked eye, on each of the scales of the hake.

The interests of Public Health in its medical aspect would seem to have always received support in the Union of South Africa. In the year 1911–12, for instance, the sum of one hundred thousand pounds was expended; in the year of the influenza epidemic three times that sum. The present rate of expenditure is in the neighbourhood of a quarter of a million. There are many public bodies who concern themselves with health conditions in the Union and they are all in touch with the central authority. The officials of the Public Health Department were eagerly waiting for this new Food and Drugs Act to become operative. The growth of industry in South Africa and its bearing on the future of the nation has been fully recognised if the statute book may be taken as a reliable guide. Thus the system of weights and measures was unified by the Act of 1923; the growth of industry encouraged by such Acts as that of the Iron and Steel Industry Encouragement Act of 1922; industrial machinery has been made to run more smoothly by the Industrial Conciliation Act, 1924, and the Wages Act, 1925. Public Health has been safeguarded by the creation of the Public Health Department and by the Public Health Act, 1919, and the Medical, Dental, and Pharmacy Act, 1928; but it was only six months ago that the Act under review came into operation, and the matter with which this Act is concerned lies at the very foundations of public health. The Bill was introduced by the Minister for Public Health on the 2nd February, 1928; and read for the second time on the 27th February. It received the cordial support of both Senate and House of Assembly. Not a dissentient voice was raised. Everyone was eager to support the urgent representations that had been made by such public bodies as the Chambers of Commerce and Industry, the Board of Trade and Agriculture, the Union Council of Public Health, and all the larger municipalities. The Bill had been drawn up after a careful study of similar Australian, New Zealand, and United States legislation. The existing Acts were hopelessly out of date. The Natal and Free State Acts had been founded on the Cape Province Act, and this in its turn on the English Act of 1875, so that legislation was over fifty years old at the time of repeal. Official figures showed that harmful adulteration might be as high as ten per cent. of the samples submitted and these figures certainly did not give a true idea of the extent of such adulteration. As to adulteration with non‐injurious substances it may be sufficient to state that 27 per cent. of butter samples taken in Cape Town contained from 11 to 6 per cent. of foreign fat. Coffee is almost a universal drink among the Dutch population of South Africa, but owing to the inadequacy of the laws the country had, in the words of a witness in Committee, become “ a dumping ground ” for coffee of such an inferior kind that it is difficult to imagine anyone who could get anything better drinking it. Nevertheless it was described by the vendors in such glowing terms as to call forth protests from the Brazilian consul. Sometimes “ coffee ” was not coffee at all. It might be “ banana skins !” Sometimes it was worse than this. Such was a consignment of coffee from Hamburg. It had been in store for more than two years, and its first use was to nourish a large population of weevils—we understand that coffee must be two years old and over before this can happen. These creatures had made such good use of their opportunity that not much was left of the original coffee. As such stuff was only fit for the rubbish destructor it went to South Africa. The bits of beans plus weevils were embedded in a clay matrix, of the proper shape, to give them coherence, baked, stained, and polished—by the way it may be said that the staining and polishing of coffee had by this time assumed the character and dimensions of a skilled industry. Fortunately at this stage of the proceedings the health authorities at Cape Town intervened. It was stated by the Minister who introduced the Bill, with some reserve, that the incidence of adulteration had reached such proportions that the commercial morality of the Union in general was beginning to deteriorate. We should think so. There was certainly little to encourage the ordinary trader to put Sunday school maxims into practice. Fortunately public patience broke down before public health. On the 1st March the Bill was read for the first time in the Senate. It went into the Committee stage on the 8th. Here the usual revelations were made. Milk had, of course, received its full share of attention. So much so indeed that the Act forbids a milk vendor to carry skim milk or water in the same cart when delivering whole milk. It also appeared in evidence that a dairyman had only to keep two or three cows, which yielded inferior milk, in his herd, water the milk of the lot and plead the cow, when prosecuted, with impunity. More than that such a cow was actually hired out to another milk vendor, whom the authorities were wicked enough to prosecute, so that he might take advantage of the peculiarities of the animal and the weakness of the law. It is said that Huxley had great faith in the elasticity of the Hebrew language in the hands of Biblical commentators, it cannot surpass our belief in the almost infinite possibilities of the cow when milk prosecutions are “ going,” but this new use for old cows had not occurred to us. An important witness stated that in his opinion the 3 per cent. minimum for fat in milk is very low, very little lower indeed than the average standard for milk in Cape Town. Cape Town milk it seems is poorer in fat than up country milk. This has been attributed to the Friesian cattle as in “ short horn ” districts, the fat percentage is always higher. Nevertheless Act No. 13, 1929, Chap. II., Part C. s. 17 (3) still declares the minimum fat content for milk sold for domestic purposes to be 3 per cent. Thus, it seems to us, a good opportunity of raising the minimum legal fat content to the great benefit of everybody has been missed. Most assuredly it will not readily recur. No doubt there would have been strong opposition on the part of the trade had any attempt been made to raise this low standard. There always has been. If we had had any doubt on the subject of trade opposition that doubt would have been removed by the following. The same witnesses stated that all the best brands of herds in the Cape Peninsular, are tested for tuberculosis which is “ very prevalent. ” He agreed that milk from tuberculous cows was “ highly dangerous to infant life. ” In reply as to whether it would not be safer to have all herds compulsorily tested, he said: “ It is a question they are afraid to tackle. ” They have been at it for the last 25 years. “ Q. What is the reason? Is it because ” tuberculosis is too prevalent in the Cape A. “ No. I think it is because it affects so many people. “ Had they started it 25 years ago there would not have been this trouble to‐day. “ During the past few years manufacturers of fruit juices and the like had written asking for particulars of food standards and enclosing copies of analyses. It had to be stated in reply that there were no food standards, but that a draft Food and Drugs Bill had been prepared and would probably be before the House during the next session. The Assistant Health officer of the Union who made this statement added, “ I have had to resort to this method of excluding adulterated food for the last three or four years and cannot carry on much longer. ” To send fruit juices to the land of fruit seems rather like sending coals to Newcastle. However, the addition of pectinous matter to preparations of fruits naturally deficient in pectin is well known, necessary, and permissible. But if this be done with the object of overloading, a jam declared to be made of one kind of fruit with a cheaper undeclared pulp it is a fraud which the Act is drawn to prevent. Chap. V. s. 42 empowers the Minister to make regulations under the Act and publish them in the Gazette. In the issue of the 28th March, p. 9, “jam” is defined. No mineral acid, flavouring substance, nor any vegetable substance save that derived from the varieties of fruits named on the label are permitted, but the jam may contain “a trace” of fruit‐derived malic, citric or tartaric acid, colouring matters as scheduled (p. 4) and added pectin not exceeding 0·3 per cent. calculated as calcium pectate. In “Fruit jelly” this may be 0·6 per cent. It is evident that without this regulation a consumer in this country of South African fruit products would have had no assurance that he was not getting synthetic products of European manufacture in South African fruit tins. As a last instance of the ease with which the law might be evaded and adulteration practiced the following may suffice. An inspector in the Cape Province asked for some “ mixed coffee. ” It was supplied him labelled “ mixed coffee ” with a verbal intimation that it contained 25 per cent. of chicory. It did, and 10 per cent. of ground acorns in addition. The conviction which followed was quashed on appeal by Mr. Justice Solomon on the grounds that acorns cost as much as chicory, that they were not shown to have been added to fraudulently increase the bulk, and that there was no evidence that acorns were injurious to health. It need hardly be said that this decision, extra‐ordinary thought thought it may seem, was in strict accordance with the letter of the law in this case, presumably ss. 6 and 7 of the Cape Province Act. Readers who may have followed us so far will probably by this time have come to the conclusion that any change in the law would have been for the better in the interests of the public health and the commercial reputation of the Union. Moreover as the instances of rascally practice that we have cited do not seem to have been at all “ out of the way, ” the successful continuance of such practice under what really amounted to legal protection would induce a belief that the people who would put up with such things must, in the words of Oriental euphemism, be “ afflicted of God ”; and belief in the existence of this unhappy state of things would have been considerably strengthened by the knowledge that at the very time they were spending thousands every year in the interests of public health, the Department of Public Health itself was almost hopelessly oppressed by the incubus of sub‐fossil legislation fifty years behind the times. That while the country was being advertised as a tourist ground and health resort no one from Cape Town to Johannesburg could be sure that any food product he might buy would not be grossly and harmfully adulterated. That while they were building up an extensive overseas trade in foodstuffs they were content to eat and to drink any rubbish that might be foisted on them. While the delay of the Government in amending the law and so putting an end to a state of things that had apparently become a sort of public scandal is hard to understand. It has taken fourteen years! We recall the action of Mr. Snodgrass in the street row in Ipswich who “ in a truly Christian spirit, and in order that he might take no one unawares, announced in a very loud tone that he was going to begin, and proceeded to take off his coat with the utmost deliberation. ”

The milk supply of our country, in one form or another, has been the subject of discussion year after year at Congress meetings. Its importance is an admitted fact, but, notwithstanding, I again venture to call attention to the matter. On this occasion, however, I do not propose to touch much of the ground already covered by former papers, but to consider the results of experiments and observations made while dealing with milk supply under the Sale of Food and Drugs Acts. For many years dairy regulations have been in force throughout the country which deal with the construction of floors and walls, and with lighting and ventilation. The owners of dairy farms in many parts of Scotland have spent large sums of money in improving their farms. Indeed, some enthusiasts have gone the length of introducing a system of heating and mechanical means of ventilation. It is only reasonable to pause and consider the practical results of these improvements, and to discover who are reaping the benefits from a milk supply standpoint. Do the owners of dairy farms receive anything like a fair return for their capital outlay? No. It is a well‐known fact that rents are on the down grade. Is the farmer of to‐day in a better financial position than formerly? No. He will tell you that the working of a “modern dairy” is more expensive than in the old steading, and that there is less flow of milk from the cows in the large airy byre than in the small old “biggin.” The price of milk is considerably less than it was fifteen or twenty years ago. At that time it ranged from 10d. to 1s. per gallon, and it is well known to you that hundreds of gallons of milk are now sent into our large cities for at least a distance of 100 miles, carriage paid, at 7½d. per gallon. In some cases the price is 9d. per gallon during the winter and 7½d. in summer. A farmer I know has a contract with a dairyman to supply him with 20 gallons of sweet milk, 16 gallons of skim milk, and 4 gallons of cream every day at an average rate of 7½d. per gallon all the year round. I have proved, by having test samples taken of the sweet milk, that it contains an average fat of 4.89 per cent. in 16 gallons. Neither the owner nor occupier of the farm can be any better off so long as such small prices prevail. Does the profit then come to the consumer? It does not.

From what was said in the previous article on this subject, it is obvious that a new profession has arisen in consequence of the passing of the Food and Drugs Acts, and of the fact that their execution is now compulsory on all the local authorities legally concerned with the matter. This profession, under the fostering influence of certain scientific and academic bodies, now includes a considerable number of individuals who, in their general culture and education, as well as in their special scientific qualifications, are at least on a par with the members of the older so‐called “learned” professions. In the course of the early development of the analytical profession, as a body, the old Society of Public Analysts was a most potent influence for good, and did, and still does under another but unfortunate name, very excellent work in collecting and publishing any additions that are made to our scientific knowledge of matters connected with the analysis and adulteration of food by the scattered workers in this country and abroad.

What proof have the public, independent of the assertions of the makers, that all the firms whose products are sold indifferently by the shopkeepers use only the best materials; or, indeed, that a large number of the articles sold are not mixtures more or less objectionable or fraudulent ? This, in effect, is the question put by a writer in a West of England newspaper, and it might be used as a text upon which to write a lengthy homily on the adulteration question and on the astonishing gullibility of the public. As a matter of fact the only evidence of the character and quality of food and other products, in regard to which there is no independent guarantee, is that which is afforded by the standing of the makers, and to some extent of the firms which offer them for sale. And this evidence cannot, under any circumstances, be looked upon as constituting proof. The startling allegations so commonly put forward by advertisers with respect to their wares, while they may be ineffective in so far as thinking people are concerned, must nevertheless be found pecuniarily advantageous since the expense involved in placing them under the eyes of the public would otherwise hardly be incurred. Many of these advertised allegations are, of course, entirely unjustifiable, or are incapable of proof. It may be hoped that the lavish manner in which they are set out, and their very extravagance, may, in time, result in producing a general effect not contemplated by the advertisers. In the meantime it cannot be too often pointed out that proof, such as that which is required for the satisfaction of the retailer and for the protection of the public, can only be obtained by the exercise of an independent control, and, in certain cases, by the maintenance of efficient independent inspection in addition, so that a guarantee of a character entirely different to that which may be offered, even by a firm of the highest eminence, may be supplied.

IN order to be able to discriminate with certainty between butter and such margarine as is sold in England, it is necessary to carry out two or three elaborate and delicate chemical processes. But there has always been a craving by the public for some simple method of determining the genuineness of butter by means of which the necessary trouble could be dispensed with. It has been suggested that such easy detection would be possible if all margarine bought and sold in England were to be manufactured with some distinctive colouring added—light‐blue, for instance—or were to contain a small amount of phenolphthalein, so that the addition of a drop of a solution of caustic potash to a suspected sample would cause it to become pink if it were margarine, while nothing would occur if it were genuine butter. These methods, which have been put forward seriously, will be found on consideration to be unnecessary, and, indeed, absurd.