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The purpose of this paper is to analyse the content and some synthetic food colourants, total fats, nitrate and nitrite in both advertised foods (AF) and serum and urine samples of children (8 to 12 years) and their impact on childrens’ diet and health.

Analysis of the content of the AF was done by watching the three Egyptian children’s channels (ECC) for 38 hours. Amaranth, Indigo Carmine, Tartrazine, nitrate and nitrite were analysed in all AF and in serum and urine specimens of children. However, total fats were only analysed in the advertised processed meats and in the restaurant dishes. Lipid profile was also estimated in children.

The AF accounted for 46-54 per cent of the total advertisements presented. The advertised restaurant dishes were predominantly high in fats, 63 and 55 per cent in restaurant dishes and processed meats, respectively. Tartrazine was the only food colourant found in soft drinks and jelly powders measuring 0.2-15 µg/ml and 25-125 µg/g, respectively. The average levels of total nitrate and nitrite were higher than the acceptable daily intake of the Egyptian and WHO limits (125 mg/kg). Urinary Tartrazine and serum and urinary total nitrate and nitrite were significantly higher in the viewers’ children for the ECC and at borderline for lipid profile compared to non-viewers’ children.

The most harmful effect of these advertisements is the cumulative effect of AF that undermines progress towards a healthy diet for children. AF may expose children to non-communicable disease in the future.

The local policy context requires action to set clear rules for children’s food advertising and monitor processed meat products to tackle exceeded levels of nitrate and nitrite.

This is one of the first studies to analyse colourants, fats, nitrate and nitrite in AF and in the serum and urine of children. This research shows a large number of AF (1,112) in the ECC for 38 hours with statistically significant increase of Tartrazine, nitrate and nitrite in AF (p<0.0001) and in biological fluids (p<0.05).

The curing of pork for the purpose of manufacturing bacon and ham is fundamentally a process of salting that was originally used merely as a method of preservation. A century and a half ago the curing of pork was done on the farm or in the home. To‐day, practically all the bacon and ham consumed is mass‐produced in factories, and the concern of manufacturers is to obtain the best standard products by the simplest means. The report that follows is not concerned with those factors in the quality of the product that can only be standardised by control of the conditions under which the pig is reared and of its treatment immediately before slaughter, such as the conformation and composition of the carcase. It is concerned only with those factors that are definitely due to the process of curing, namely, the cured flavour, the production of the red cured colour of the lean meat and the even distribution of salt. It is now well known that the production of the red colour is due to the interaction of a nitrite, such as potassium or sodium nitrite, with the haemoglobin of the meat, which yields a pigment, nitroso‐haemoglobin, which is more permanent than haemoglobin. On the other hand, it is known that such nitrites may have harmful effects upon animals, if taken indiscriminately into the alimentary system, so that the view generally held is that the amount of nitrite in staple foods should be as low as possible. In the traditional method of curing, nitrite is not added to the curing salt. Nitrate (saltpetre) is added. The fact that the red colour develops is due to the action of certain bacteria in reducing a portion of the added nitrate to nitrite. In this indirect method of introducing nitrite into the cure, the amount of nitrite in the product when it is finally consumed depends upon many variables, and cannot be easily or strictly controlled. The traditional procedure of adding nitrate is still the basis of commercial practice in this country ; in fact, the addition of nitrite is illegal. The traditional method of curing on the farm or in the home has, however, been modified in one very important way in the modern factory. Traditionally, dry salts were used. To‐day, the usual method employed in factories is salting by immersion in tanks of pickle, combined with the forcible injection into the carcase of a solution of common salt and saltpetre. Two advantages have been gained by this change ; first, a milder cure, containing a relatively small and fairly evenly distributed amount of salt, and, secondly, speed and economy. From the points of view both of the consumer and of the manufacturer, a number of questions emerge from this review of the present situation in this country. Thus, it may be asked : (1) Does nitrate contribute in any essential way, in addition to serving as a source of nitrite, to the process ? Does it, for example, contribute essentially to the cured flavour or to the keeping properties of the product ? (2) Similarly, do bacteria contribute in any essential way, in addition to acting as agents in the production of nitrite ? (3) How far are the temperature, time and acidity determined in tank‐curing by the need for controlling the type of bacterial flora and its activity ; and what advantages could the manufacturer obtain if the need for the bacteria and for the control of their activity did not exist ? (4) Would the elimination of the nitrate and the bacteria from the process help toward obtaining more uniform and lower amounts of nitrite in the finished product ? It has therefore been felt essential to carry out the experiments described in this report, although it may appear at first sight that they cover similar ground to that traversed as long ago as 1925 in the U.S.A. under the auspices of the Bureau of Animal Industry of the United States Department of Agriculture and of the Institute of American Meat Packers. There is, however, a basic difference in the aims of the two pieces of work. The American work, conducted on an extensive scale in a number of packing houses, was a successful demonstration that the direct use of sodium nitrite in American cures was commercially practicable, and had many operative advantages over the traditional method, which relied entirely for the production of nitrite on the bacterial reduction of nitrate. As regards the product, it was found to be at least equal in all respects to that produced by the older method. The work was not designed to elucidate the mechanism of curing, i.e., to isolate the factors responsible for the production of the cured flavour and, in fact, no steps were taken to eliminate the factor of bacterial action. The results did, however, show that the presence of nitrate, as such, was not essential for the flavour of American bacon and hams. The aim of the present work has been twofold : to determine the relative importance of the various factors responsible for the production of the cured flavour ; and to determine whether the direct use of nitrite in English cures, which are very different from those used in America, would give a satisfactory product, as judged by English standards. The first objective is not only of scientific interest, but is fundamentally related to the second. If a clearly defined factor can be shown to be responsible for the production of the cured flavour, any consequential modifications in English commercial practice that may suggest themselves can be viewed and developed on a scientific and not an empirical basis. The work therefore included a critical comparison between, first, current procedure in the factory, based on the traditional process of adding nitrate and depending on bacterial activity for the production of nitrite ; secondly, nearly sterile procedure in which both nitrate and nitrite were added in addition to sodium chloride ; and thirdly, nearly sterile procedure in which only nitrite was added. Other aspects of curing were also investigated, including the rate at which the freshly‐slaughtered pig is cooled, the action of heat on the nitrite in bacon, the minimal desirable amount of free nitrite in bacon, the bacterial flora of pork, bacon and mature tank‐pickle and the amounts of salt and nitrite in commercial bacon. The results of the experimental cures, as will be seen, establish a strong presumption that the characteristic flavour of bacon is due to the action of sodium chloride and nitrite on the flesh, and that the presence of nitrate and microbial action during pickling and maturation are not essential. The work also raises, but does not settle, other important issues. For example, what is the process by which nitrite is lost in the meat, other than by combination with haemoglobin, and what are the effects of temperature, time, acidity, etc., upon the rate and extent of this process ; does the presence of nitrate in the tissues appreciably retard or inhibit the growth of putrefactive anaerobes? These problems are now being investigated, but in the meantime it seems undesirable to defer publication of the results already obtained. What is the immediate practical upshot of the work ? The basic principles of the curing of bacon can be taken as fairly established, and they do point to the possibility of recasting current practice in this country in a way that would give the curer really effective control over the quality of his product, so far as it is determined by the actual process of curing. But it would be premature at this stage to attempt the radical changes in method that are implied. Before that could usefully be done it would be necessary to carry out a comprehensive series of experiments on a larger scale, and with an adequate range of raw material (i.e., carcases), in order to establish how far the results obtained on the small scale are reproducible in the factory. The question of this further work is under consideration.

Green leafy vegetables (GLVs) are important components of a balanced diet especially in developing countries where the major requirements of micronutrients are met. However, GLVs also contain significant amounts of oxalate, nitrate and nitrites, whose role in the human diet is constantly changing. The current study explored the behavior of nitrate, nitrites and oxalate in lactic-fermented GLVs with an intention to develop functional foods based on them.

Selected strains of beneficial lactic acid bacteria were used for the controlled fermentation of GLV, while an identical portion was subjected to spontaneous fermentation. The nitrate and nitrites were monitored spectrophotometrically, while oxalate contents were quantified by both titrimetric and by high-performance liquid chromatography throughout the duration of fermentation.

More than 90 per cent of individual constituents studied remained intact in the GLVs paste after the six-day controlled fermentation period. However, there was significant difference between the controlled and spontaneously fermented samples in terms of oxalate, nitrate and nitrite contents.

Controlled lactic fermentation although superior in all other aspects may not be able to lower the anti-nutrients present. The advantages of spontaneous fermentation vis-à-vis controlled fermentation are discussed. The work will bring out the importance of the beneficial effects of GLVs and the effect of lactic fermentation.

Fumes, grit, dust, dirt—all have long been recognized as occupational hazards, their seriousness depending on their nature and how they assail the human body, by ingestion, absorption, inhalation, the last being considered the most likely to cause permanent damage. It would not be an exaggeration to state that National Insurance (Industrial Injuries) provisions, now contained in the Social Security Act, 1975, with all the regulations made to implement the law, had their birth in compensating victims of lung disease from inhalation of dust. Over the years, the range of recognized dust disease, prescribed under regulations, has grown, but there are other recognized risks to human life and health from dusts of various kinds, produced not from the manufacturing, mining and quarrying, &c. industries; but from a number of areas where it can contaminate and constitute a hazard to vulnerable products and persons. An early intervention by legislation concerned exposed foods, e.g. uncovered meat on open shop fronts, to dust and in narrow streets, mud splashed from road surfaces. The composition of dust varies with its sources—external, atmospheric, seasonal or interior sources, uses and occupations, comings and goings, and in particular, the standards of cleaning and, where necessary, precautions to prevent dust accumulation. One area for long under constant scrutiny and a subject of considerable research is the interior of hospital wards, treatment rooms and operating theatres.

Considerable attention has been paid in the last few years to a class of compounds called ‘Nitrosamines’ which could be formed in foods as the result of a reaction between nitrites and amines. In certain species of laboratory animals under specific conditions, some of these nitrosamines have been shown to be carcinogenic. Food scientists have had to look at the use of nitrites in foods and have had to establish whether there is any possible danger in their use

Further research is being conducted to assess the appropriate levels of nitrate, nitrite and N‐nitroso compounds in the diet. So far, there is insufficient evidence to show what levels are dangerous. A report on these compounds has reviewed previous research, and the main findings indicate that dietary nitrate intake in Britain is in line with other Western countries. More information and research is needed about levels in cured foods and additives, in order to assess the possibility of harmful effects.

The weather in the Arabian Gulf region constitutes an environment that is corrosive to carbon steel. In the Gulf region, atmospheric corrosion is aggravated further by the high salinity of Gulf sea‐water. In addition, sulphur dioxide and deposits from combustion products tend to make the atmosphere in the Gulf region even more corrosive. Various inhibitors are reported in the literature that can help in the prevention of metal corrosion in aqueous environments. Among these, sodium dihydrogen orthophosphate, sodium benzoate, sodium nitrite and sodium nitrate were obtained and the effectiveness of certain corrosion inhibitors on carbon steel specimens was examined in a simulated atmospheric corrosion environment containing 2% NaCl and 1% Na₂SO₄ with various inhibitor concentrations. Test specimens were prepared from locally produced carbon steel reinforcing bars. It was found as a result of the test programme that treatment of the steel with 10 or 100mM sodium dihydrogen orthophosphate for one day at room temperature resulted in the best inhibition of corrosion. The results also demonstrated that inhibitors such as sodium benzoate and sodium nitrite were only similarly effective, as was sodium nitrate. Plans further study to examine the inhibition performance of sodium dihydrogen orthophosphate under actual atmospheric conditions.

There are a number of environmental concerns which periodically catch the headlines and subsequently fade from sight, not because the problem has been solved but because the issue has ceased to be news. A recent example of this media ephemerality involved reports that the water supplies of some parts of the country were ‘seriously’ contaminated with nitrogen (in the form of nitrate); that the problem was caused by chemical fertilisers and getting rapidly worse: and that the EEC was taking action to stop it. And yet, within a few days, nothing more was mentioned.

The article reports on the extension of a previous pilot study on denitrification of water in a demonstration plant: the results showed that four reference loads of nitrate (0.45, 0.80, 1.15 and 1.45 kg nitrate‐N per m⊃3 per day) were successfully controlled by the treatments suggested: biodenitrification in a biological reactor using a carbon substrate (sucrose).

This study aims to describe the development of a battery-operated portable colorimeter for on-site determination of water quality in aquaculture.

A simple and economical colorimeter is built using light sources of different wavelength and a light-dependent resistor combined with an electrical circuit. The whole system was fabricated as to fit into the pocket or palm for easy handling. The developed portable colorimeter was calibrated for estimation of nitrite. Further, the performance of developed portable colorimeters was compared with the commercially available colorimeter.

Three colorimeters with different light sources were developed and calibrated for determination of nitrite in water. Among them, colorimeter with yellow light source exhibited higher potential for determination of nitrite in the range of 0.5–3.5 ppm. Further, the results of the developed colorimeter are comparable with the commercial colorimeter.

The portable colorimeter developed in this study exhibits potential for determination of nitrite in aquaculture. Determination of nitrite at low concentrations is important for assessing the quality of culture as well as wastewater in aquaculture industry. The accuracy, portable nature, economy and simple operation of these portable colorimeters offer opportunity for on-site determination of water quality parameters in aquaculture.