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Aloe vera gel has nutritional and therapeutic properties due to presence of bioactive components. The aim of this study is to investigate the effect of pasteurization and storage time at different temperatures on some bioactive components of Aloe vera gel juice.

Aloe vera gel juice (Aloe barbadensis Miller) was pasteurized at 90°C for 1 min and stored up to 30 days at 4 and 25°C. The effect of pasteurization and storage time on glucomannan, vitamin C, DPPH inhibition (percent) and color of the juice was evaluated.

The results showed that pasteurization reduced vitamin C content and antioxidant activity 16% and 57%, respectively. During storage at 4 and 25°C, vitamin C and glucomannan contents reduced from 84.47 to 54.96 and 46.82 mg vitamin C/100 g dm and from 2.11 to 1.77 and 1.71 g/L, respectively. DPPH inhibition (percent) and Browning index (BI) increased significantly at both storage temperatures, which was more intensive at 25 than 4°C.

This paper is believed to be the only one which investigates the effect of thermal pasteurization and storage time at different temperatures on some bioactive components of Aloe vera gel juice.

Supercritical carbon dioxide (sc-CO₂) is a promising novel treatment that might be used in the food industry, such as sc-CO₂ pasteurisation and sc-CO₂ drying. Before sc-CO₂ treated foodstuffs may be introduced to European market, they have to be authorised according to novel food regulation. Therefore, the purpose of this paper is to give an overview of available literature data on sc-CO₂ treated fruits and vegetables, which might be used for novel food authorisation.

The paper is based on literature data available via Science Direct, EBSCO and Wiley concerning sc-CO₂ pasteurisation and drying of fruits/vegetables. Studies performed on animal foodstuffs were manually excluded, while articles related to novel foods and legislation were included in the study.

Database search resulted 34 articles related to microbiological and compositional/nutritional changes in sc-CO₂ treated foods. Obtained data indicated that sc-CO₂ pasteurisation is effective in inactivating microorganisms in liquids, while no general conclusion on the microbiological quality of sc-CO₂ pasteurised solid foods or sc-CO₂ dried foods could be made. Available literature data showed that sc-CO₂ pasteurisation did not result in significant compositional/nutritional changes in liquids, while for sc-CO₂ pasteurised solid foods or sc-CO₂ dried foods, one is not able to make common conclusions due to insufficient research data. Therefore, additional research and case-by-case study for each treated food have to be prepared.

This study is original to the extent that it brought together available information on sc-CO₂ pasteurised and dried foods, needed the novel food application.

Jambolan has be used as a diabetes-treatment aid, and it has become quite popular; studies have been carried out over the years on this fruit because it presents high activity against superoxide anion and hydroxyl radicals due to the bioactive compounds that may play an important role against oxidative stress. No studies have been reported on the effects of pasteurization on the bioactive compounds of jambolan tropical juice. The paper aims to discuss these issues.

For evaluation of the effects of pasteurization on jambolan juice bioactive compounds, a complete compound and rotational experimental design was carried out by varying temperature (80–90°C) and time (45–75 s). The bioactive compounds (total phenolic, total anthocyanin and antioxidant activity) and the enzymatic activity of enzymes (enzymatic browning) were assessed.

The study of bioactive compounds in the pasteurized juice of jambolan, showed that the total phenolics (TP) and ABTS antioxidant activity presented statistical significance (p<0.05). The action of enzymes causing enzymatic browning was only observed in the standard sample. The optimization of the pasteurization process with the maximum bioactive compound retention was 91.65°C for 69.45 s. The optimal point found is in agreement with studies on thermal treatment that recommend using short times at high temperatures for better retention of food constituents.

The incidence of chronic diseases in humans has increased significantly over the years, some bioactive phytochemicals present in fruits may help against these diseases, so the production of tropical jambolana juices can help to nourish and regulate the consumer health. Therefore, studying the maintenance of bioactive compounds present in this product could be an alternative for the production of healthier foods.

At the invitation of Miss Olga Nethersole, founder and honorary organiser of the People's League of Health, a number of medical and science councillors and official members of the League met at luncheon at Claridge's Hotel, London, on October 18th, to welcome the members of the newly appointed Veterinary Council. The speeches which followed dealt with the campaign of the League for a safe milk supply, and the part which veterinary science, in conjunction with the other interested professions, might play in attaining the desired end.—Prof. T. J. Mackie, D.P.H., of the Department of Bacteriology, Edinburgh University, said that the formation of the new Veterinary Council was a significant event in the history of the League. It emphasised the absolute necessity of enlisting the co‐operation of the veterinary profession in the campaign for human health. If we were to guard our own health we must pay due respect to the health of our domestic animals, and particularly those from which we received our essential foods, such as milk. It was common knowledge to both the medical and the veterinary profession that our milk supplies, collectively speaking, were not safe, and that, in fact, they might carry a constant menace to the public health. Milk‐borne tuberculosis dominated the whole question of our milk supplies. It must be remembered, however, that tuberculosis was only one of the milk‐borne infections. There were others such as diphtheria, enteric fever, scarlet fever, and undulant fever. Yet there was distinct apathy, and sometimes antipathy, to the simple measures that would regulate this state of affairs. The League were to be congratulated on having performed a valuable public service in their critical survey of the question of bovine tuberculosis, and bringing out in fair relief the essential facts in regard to tuberculosis of animal origin in human beings. Some of the facts in the report could not be too often and strongly repeated. In England and Wales, for instance, it had been shown that every year the bovine type of tuberculosis bacillus caused at least 4,000 new cases of human tuberculosis and at least 2,000 deaths. And seven per cent. of the ordinary samples of vended milk contained this organism. He could speak feelingly, for in Scotland they had rather more than their share of tuberculosis of the bovine type in the human subject. When one reflected on all that had been done in various ways for the improvement of public health, it seemed almost incredible that food was being sold daily with a seven per cent. and sometimes a 14 per cent. chance of it containing a germ capable of producing a crippling or even fatal disease without any warning to the public. If tuberculosis were not an insidious disease, but an explosive epidemic, even if its incidence were not so high, these conditions would not have been tolerated so long as they had been. The veterinary profession recommended the eradication of disease from herds as the fundamental remedy. It was the fundamental remedy, but even the highest grade tubercle‐free milk might carry a very dangerous infection, and, in any case, he did not think the objects which the veterinary profession had at heart, and with which he sympathised, and compulsory or universal pasteurisation on the other hand, were mutually exclusive. He did not see that pasteurisation would set back the clock of progress against the eradication of tuberculosis in the herds. The problem was an urgent one. The eradication of the disease from dairy cattle must proceed slowly and against difficult obstacles, and they could not wait. It was estimated that, if the eradication of tuberculosis were continued at the present rate in this country, it would be 400 years before we reached the stage that had been reached in America. Even if it were expedited, it must remain a relatively slow process. He could not understand those individuals who were content to tolerate the continuance of bovine tuberculosis in the human being in the hope that some day a raw tubercle‐free milk might be universal. Our agricultural and public health organisations were doing the people an injustice in their tacit sanction of the ordinary raw market milk. If they were not prepared to countenance compulsory pasteurisation, at least in the large communities, the only alternative was an official designation of that milk, which would make it clear to the public that it was not free from potential danger. He sometimes wondered what would be the effect of such an official designation if there were displayed in the retail milk shops an official notice stating to the public that such milk was not free from diseases dangerous to human subjects, and that they were warned not to use it without previous sterilisation. He was sure that if that were done the problem would very soon solve itself. Some Local Authorities were pressing hard for powers of compulsory pasteurisation. He thought the League might very well carry on the campaign by educating public opinion and influencing Parliament to that end. If the Government Departments were not willing to move in the matter and take action, then the public must be informed in the clearest possible terms what the position was. The League, in tackling the milk problem by its own methods, had a magnificent opportunity of making a great contribution to the important cause for which it stood.—Professor J. Basil Buxton, of the Institute of Animal Pathology at Cambridge University, said that pasteurisation could not by any means dispense with the necessity for clean milk. They must produce clean milk, however much or however little they might cook it or otherwise treat it afterwards.—Professor Gaiger, President of the Royal College of Veterinary Surgeons, said that they had an enormous job in front of them if they were going to make our milk free from the germ of bovine tuberculosis.—Sir Leonard Hill said that if we could get the people on the right diet we should enormously diminish the amount of disease. Of all the foods milk was one of the most important, and we ought to make the supply safe. Pasteurisation should be made compulsory at once.—Major D. S. Rabagliati, Chief Veterinary Inspector to the County Council of the West Riding of Yorkshire, told the gathering of the important work carried out by his Local Authority, who were the pioneers in the veterinary inspection of cows. He maintained that even if there were compulsory pasteurisation that was no reason why they should not have a clean supply of milk.

Quality specifications Egg products, which are used extensively in the baking and confectionery industries, are pasteurised to kill any food‐poisoning salmonellas that may be present. In the UK there is a statutory requirement to pasteurise whole eggs for at least 2.5 min at a temperature not lower than 64.4°C. There is no statutory requirement for the pasteurisation of egg albumen (egg white), but treatment for the same period at a temperature not lower than 57.2°C is common practice.

The recent debate in the House of Lords showed that the official plans for milk of better quality, set out in the White Paper three years ago, are only slowly being put into effect. A more active policy was, however, promised by Lord Ammon when labour and plant made it possible. Farmers have come to accept the view that a safe milk supply depends both upon the improvement of animal health and on the heat‐treatment of milk. Some recent figures issued in the Monthly Bulletin of the Ministry of Health show what the pasteurisation of milk has already achieved in reducing the number of deaths among young children from abdominal tuberculosis, a form of the disease which is generally due to tubercle bacillus of bovine origin. In 1921, in the administrative county of London, 136 out of every 1,000,000 children died from this disease. In 1944 the corresponding figure was six. In rural areas the rate in 1921 was 252 and in 1944 still sixty, or ten times the London rate. The London figures for 1944 show a reduction to one‐twenty‐third of the 1921 rate, while for rural areas the reduction is only about one‐quarter. These figures suggest a high degree of correspondence between the increase of pasteurisation and the decrease of mortality from abdominal tuberculosis. In 1944 99 per cent. of London milk supplies was pasteurised; and though more milk has been treated in rural areas and in urban areas outside London during the past twenty years, nothing like the London standard has yet been generally reached. Large towns such as London are at one disadvantage in regard to milk safety in that they receive their supplies in bulk, and samples, before pasteurisation, show a high degree of infection. To this extent rural areas might be expected to have better figures. That they do not would appear to be proof of the greater safety provided by pasteurisation. In the House of Lords debate Lord Rothschild estimated the annual casualties from raw milk contaminated by bovine tuberculosis germs as between 7,000 and 8,000. The case for speedier progress with the provision of pasteurisation plant will be generally endorsed. This development under the auspices of the Ministry of Health needs to be supported by a vigorous effort by the Ministry of Agriculture to build up the health of dairy herds. The problems involved in establishing clean areas, beginning with isolated districts and extending them gradually until in ten or fifteen years' time the whole country is clear of tuberculosis and contagious abortion, were recently discussed in these columns. The Milk Marketing Board, the producers' organisation, has now declared its support for a national drive to clean up the dairy herds; and the Government are assured of general support when a comprehensive plan for ensuring safety in milk is put forward.

In the June issue of THE BRITISH FOOD JOURNAL reference was made to a recently issued Report by the Ministry of Health upon the subject of bovine tuberculosis. In that Report the pasteurisation of cow's milk is referred to as a means of reducing the resulting human infection, and it is stated that “milk so treated appears to retain its valuable food properties practically unimpaired.”

The endeavour that is being made at the present time to rouse public interest in the extremely important question of the purity of the national milk supply is one that deserves unqualified praise. It is in no spirit of carping criticism that it is here pointed out that the partial and unofficial remedy by which it is proposed to diminish the risk to the consumer may in itself be indirectly a means of continuing what has become a grave public danger. No reasonable doubt can exist that pasteurization as a method of dealing with large quantities of milk in bulk and from all sources will be of considerable use. It will certainly tend, if carried into effect to the extent and in the way suggested, to greatly lessen the risk that consumers run at the present time. It will prevent a large amount of disease that arises from the consumption of impure milk. But such a method, however admirable and philanthropic in conception and sound in theory, is one that by no means answers all, or even a part of, the large number of important questions connected with the subject. The general public and honest milk dealers will, it is to be hoped, benefit by the new milk legislation that is proposed by the Local Government Board and by the London County Council. The public, however, is very apt to be caught by a phrase, and may, therefore, think that “milk pasteurization” is the beginning and the end of all that need or can be said on the subject. It is likely that the foundation of depots for the preparation and supply of pasteurized milk will blind its eyes to the fact that the evils which have rendered the establishment of such places necessary remain untouched. Indeed, the very fact that milk depots of this kind are at work may be used by interested persons as evidence that all hygienic requirements have been complied with, that for this reason veterinary considerations may be ruled “out of court,” and that the necessity for further legislation of a more fundamental and drastic kind no longer exists. The agitation that is taking place at the present moment is no new thing. For many years past the matter has engaged the most serious attention of those experts whose business it is to investigate and, as far as they are permitted, to control the quality of the milk supplies of both our town and country districts. For example, a perusal of the annual reports of the Local Government Board that have been issued since that Board was instituted in the early seventies, will satisfy any one, who takes the time and trouble to read them, that Public Analysts have from time to time animadverted in terms more or less strong on the poor quality of the milk supplied, and that even if the field of inquiry be limited to what may be called purely analytical standards the difficulties of the case are enormous, even if they be looked at from the best and the most hopeful point of view. At the present moment we are more concerned with the equally important hygienic aspect of the question. Local self‐government, while conferring a large amount of autonomy on administrative units, has naturally resulted in an almost entire absence of any definite national system that can deal with the important subject of food supply generally and milk supply in particular. At the present time it is left to the local authority to decide whether it will or will not apply for powers from the central authority—the Local Government Board—to put into force regulations under the Dairies, Cowsheds, and Milkshops Order, though in cases where this has been done the benefit to all concerned has been marked, and the necessity for such action demonstrated. The subject of the milk supply divides itself, roughly speaking, into three branches, which may be referred to under the headings of Production, Carriage, and Sale, though it is evident that no sharp line of demarcation can be drawn. With regard to all of these the law is either defective or nonexistent. Under the present “system” prosecutions are mostly instituted against persons of whom it is alleged that they have knowingly sold milk from which fat has been abstracted or to which water has been added, but even here “the difficulties connected with the administration of the Sale of Food and Drugs Acts in the case of milk have been a constant subject of discussion between the officers of local authorities and the Board's Inspectors.” What these difficulties are are well known to all who are brought into contact with the administration of the Food and Drugs Acts, but any one can satisfy himself as to them by reference to, say, the last annual report of the Board of Agriculture in this respect, keeping in mind, at the same time, the fact that only one aspect of the case is there dealt with. Under the heading of Production brief reference may be made to the subject of the cow and her surroundings. Much evidence exists which shows the urgent need for expert and unbiassed hygienic and veterinary inspection of all dairy farms, cowsheds, and cows. In much that has been recently written on the subject of pure milk in the daily press, it is somewhat remarkable to note that while the dangers that arise from drinking raw milk derived from tuberculous cows has been rightly insisted on, comparatively little reference has been made to the importance of cow and cowshed inspection. It is unfortunately the case in too many instances that the owners of cows are content to house the animals in sheds under conditions that are usually, though wrongly, thought to be fit only for pigs. This, of course, leaves entirely out of the question the fact that the animals themselves may be tuberculous or otherwise diseased, and therefore a source of most serious danger to the public health. With regard to carriage of milk it may be pointed out that the modern city draws its supply of milk from all over the country, and that this means a rail journey of frequently some hours' duration. Our modes of transporting and handling milk have not, however, kept pace with modern requirements. The frequently Arcadian simplicity of the methods in vogue would appeal the more strongly to lovers of the picturesque if they did not lead so often to the introduction of filth of all kinds into the milk cans. Lastly, regarding the sale of milk from retailer to consumer, the public itself is largely to blame for the objectionable practice of adding colouring matter to the milk. A general impression is abroad among the poorer, and therefore it may be presumed the more ignorant, consumers, that milk is not genuine unless it be what is called “cream coloured.” Hence the introduction of annatto or some less innocent substance. For the frequent presence of such substances as formaldehyde, boracic acid, and other “preservatives” no excuse of any kind exists. Such practices are simply means but too often resorted to of masking incipient putrefaction induced by tardy and uncleanly methods. At the same time, these dangerous chemical preservatives make the “food” more difficult of digestion, with results to young children and persons in weak health that are too obvious to need comment. In addition to all this the milk may be subjected, of course, to adulteration of the usual kind. Hence the present position is that against defective methods of production and sale, out‐of‐date methods of transport, absence of any national and compulsory system of inspection and control, and a law that is either deficient or hopelessly tangled, a semi‐philanthropic method is proposed which, though probably sound and admirable in itself, is almost certain to be used by the unserupulous as a means of preventing the important problem of our milk supply being attacked in the only way in which there is reasonable hope of success—that is, by an appeal to the cow and its surroundings. Unless the method of pasteurization be recognised as a useful but still a subordinate means of dealing with an already contaminated substance, it is more than likely that tinkering and generally unsatisfactory legislation will be resorted to, and that as a result of this the state of the milk supply will remain very much as it is at present.

Shelf‐life of cultured milk products is longer than milk but it is still limited. Shelf‐life of cultured milk products could be enhanced by adopting various techniques. The purpose of this paper is to describe how the longer shelf‐life thus attained would extend the market reach and would be economically beneficial to both producers and consumers.

Attempt has been made to enlighten the various techniques such as bacteriocin (nisin, Microgard^TM, natamycin, etc.), lactoperoxidase‐thiocyanate‐hydrogen peroxide system (LP‐system), high pressure treatment, post‐production heat‐treatment (thermization, microwave heating), ultra‐violet (UV) irradiation, carbonization, etc.

Application of more than one bacteriocin may be advantageous to minimize the possibility of survival of microflora resistant to a particular bacteriocin. Pasteurization, being more detrimental to dietetic properties of cultured milk products than thermization, its application is not suggested as a method of preservation. Microwave heating may be better than conventional pasteurization.

Conjugated application of various techniques would be more efficacious in extending the shelf‐life of cultured milk products. Extension in shelf‐life of cultured milk products would be economically beneficial for producers and consumers.

It is estimated that in this country alone no less than 2,000,000 tons of food annually is destroyed by reason of the depredations of rats and mice. Neither powers nor organisations existed at the outbreak of war. which were adequate for the purpose of preventing wastage, which, under war conditions, became intolerable. That there was on the Statute Book the Rats and Mice (Destruction) Act, 1919, cannot be denied, but no authority existed for the control of destructive insects and mites in foodstuffs. The powers and duties vested in local authorities under the Rats and Mice (Destruction) Act were of little avail and it was allowed to fall into disuse without alternative provision being made. The control of these several groups of pests has for some years past been dependent on the powers derived from the Defence Regulations and continued under the Supplies and Services (Transitional Powers) Act. The profession of the rat catcher is an old and universal one. In 17th century Italy the “ professional ” was recognised by his long pole bearing a square flag on which were representations of cats and mice; the Chinese equivalent bore a sign depicting a cat in a bag. An accepted method of destruction quoted in The Book of Days is one attributed to the Irish, who believed that they could rhyme any beast to death, and in particular the rat. Another prevalent notion was that rats had a presentiment of coming evil and always deserted in time a ship about to be wrecked, or a house about to be flooded or burned. In 1854 it was seriously reported in a Scottish provincial newspaper that the night before a town mill was destroyed by fire the rats belonging to the establishment were met migrating in a body to a neighbouring field. A more scientific approach is now being made to the problem. In August, 1947, a meeting was held in London to discuss the world‐wide problem of losses as a result of damage by insects, fungi and rodents, and to consider the steps to be taken to reduce such losses. Embracing a general consideration of the problem of infestation control, the meeting, convened by Dr. L. E. Kirk, head of the Plant Industry Research Branch, Agriculture Division, F.A.O., covered many phases of the subject, ranging from the economics of the problem to the toxicity of new synthetic insecticides. Accepting the principle that efficient prevention and control of food infestation was essential to the conservation of the world's food supply, the meeting recommended that:—