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The purpose of this study is simultaneous dyeing and mordanting of wool yarns with extracted cochineal dye and aluminum sulfate to the reduction of consuming energy, water and time.

The dyeing process was optimized using the response surface methodology (RSM) approach. pH, dyeing duration and the presence of additives were chosen as variables and the color strength of samples as a response. The color characteristics and fastness attributes of samples dyed in the best condition were evaluated and compared to pre-mordant dyeing outcomes on wool yarns.

The best conditions for deep dyeing wool with cochineal dye were as follows: pH 2.5, time 110 min and the ratio of aluminum: additives 1:0 at 100 °C. Color strength of dyed wool yarns by one-bath and pre-mordant dyeing methods were approximately the same. Wool yarns can dye to the on-bath dyeing method such that the dyed samples have similar color strength and fastness properties to pre-mordant dyeing.

Wool dyeing processes that use one-bath dyeing consume less water and produce fewer effluents. As a result, this strategy conserves water and energy for a higher quality of life. The findings of this study, in general, aid environmental protection.

A novel one-bath process for dyeing wool with cochineal dye at heavy depths is introduced. RSM was used to optimize the procedure and determine effective parameters on the color strength of dyed wools. Using extracted cochineal dye and aluminum sulfate in a simultaneous dyeing technique, good color fastness qualities on wool fibers were achieved.

The aim of the paper was to study the effects of mordanting methods on the absorption behaviour of cochineal natural dye on polyamide fibres.

Iron sulphate and aluminium potassium sulphate salts were used as mordanting agents, and bottom mordanting, meta-mordanting and after mordanting methods were applied in the dyeing of polyamide samples with the cochineal natural dye. Colourimetric evaluations were carried out, and the principal component analysis was used to investigate the spectrophotometric properties of the dyed samples. Fastness properties of the dyed samples were also assessed.

The obtained results indicate that the method of mordanting has a great effect on the obtained shades, absorption behaviour and fastness properties. Based on the results, it was concluded that polyamide fabrics could be successfully dyed with cochineal and combination of dyeing with different mordanting methods, and different mordanting agents would develop the range of obtainable shades.

The textile and apparel industries have been widely criticised for their role in polluting the environment. So, the use of synthetic dyes has been limited and the use of natural dyes has increased. The literature survey indicates that there have been relatively few works investigating the dyeing of polyamide with cochineal natural dye. This research studies the effects of mordanting methods and mordant types on colourimetric and fastness properties of cochineal-dyed polyamide samples.

This research concerns making wool fabrics with dye extracted from cochineal using microwave heating. The result shows good fastness properties. To promote value addition in domestic processing and to boost rural income and employment in small-scale agroenterprises, it is necessary to promote non-polluting natural dyes, which involve inexpensive equipment and small-scale operations. The exploration of new flora can be environmentally and economically viable. Our aim is to show the feasibility of providing high-quality natural dyes extracted from insects, thus improving our environment and giving opportunities to the fabric industry to catch up with the current consumer trends towards more aesthetic fabrics and natural products.

We investigate cochineal as a natural dye using microwave irradiation under different factors such as dye extraction, the pH level of dye bath, dyeing time, dye concentration, microwave power level and mordants, and compare the results with those obtained using traditional heating. The dye extraction indicates that microwave heating is a more effective method than traditional heating. The kinetic parameters are examined to determine half-dyeing time (t_½), dye affinity (Δµ°), dye rate constant (K) and heat content (ΔH).

Wool yarns are dyed with natural colouring matter that is extracted from cochineal, turmeric and madder, and mordanted with different mordants by using the exhaustion method. Many measurements of mordanted dyed wool samples have been carried out after exposure to air and light for different periods of time in the time frame of one year in an urban area (Helwan city). The variables that are measured include changes in colour and physical properties (tensile strength, tenacity and elongation) of mordanted dyed wool samples. Also, air pollution in Helwan city is determined by studying suspended and deposited particulate matter and sulpher dioxide concentrations.

Mr. LEVENSTEIN, the President of the Society of Chemical Industry, in his address delivered at Liverpool recently, dealt very fully with the question of the commercial position of Great Britain as compared with other countries, more especially Germany, and emphasised the fact that if this country is to compete successfully with her contemporaries she must, to use the words of the Prince of Wales at the Gúildhall, “wake up.” After reviewing the chief factors making for Germany's advance in industry and commerce Mr. LEVENSTEIN says: “How are we to defend ourselves? Shall we rest content as we are or bestir ourselves and awake to the irresistible fact that continued apathy and indifference mean ruin to our national position?” This is strong language but not stronger than the occasion demands, for the statistics by which these observations are backed clearly indicate a marked decadence in the national prosperity notwithstanding the years of apparent “record” trade, which, however, cannot be regarded so favourably when subjected to detailed analysis and comparison. Mr. LEVENSTEIN'S suggestions to meet this situation are as follows: (1) The appointment of a competent and expert Minister of Commerce. (2) The nationalisation and extension of our canals and waterways. (3) A measure for greatly extending and improving our secondary education. (4) A sensible reform of our patent laws.

Everyone is extremely concerned about environmental protection and health safety due to the rise in living standards. Plant-derived natural dyes have garnered much industrial attention in food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. The present study aims to focus on the elimination of the use of synthetic dyes and provides brief information about natural dyes, their sources, extraction procedures with characterization and various advantages and disadvantages.

In producing natural colors, extraction and purification are essential steps. Various conventional methods used till date have a low yield, as these consume a lot of solvent volume, time, labor and energy or may destroy the coloring behavior of the actual molecules. The establishment of proper characterization and certification protocols for natural dyes would improve the yielding of natural dyes and benefit both producers and users.

However, scientists have found modern extraction methods to obtain maximum color yield. They are also modifying the fabric surface to appraise its uptake behavior of color. Various extraction techniques such as solvent, aqueous, enzymatic and fermentation and extraction with microwave or ultrasonic energy, supercritical fluid extraction and alkaline or acid extraction are currently available for these natural dyes and are summarized in the present review article.

If natural dye availability can be increased by the different extraction measures and the cost of purified dyes can be brought down with a proper certification mechanism, there is a wide scope for the adoption of these dyes by small-scale dyeing units.

Chocolate and cocoa are made from the “beans” or seeds of several small trees, natives of tropical America, of which Theobroma cacao (L.) is by far the most important. Cocoa beans were highly esteemed by the aborigines, especially the Aztecs of Mexico and Peru, who prepared from them beverages and foods. They were brought to the notice of Europeans by Cortez and other explorers, but were not extensively imported into Europe until the seventeenth century, about the time tea and coffee were introduced from the East. At present the world's supply comes chiefly from Venezuela, Guiana, Ecuador, Brazil, Trinidad, Cuba, Mexico, and other regions bordering on the Gulf of Mexico, being gathered in these regions from trees both wild and cultivated; and also to some extent from Java, Ceylon, Africa, and other parts of the Old World, where the tree has been successfully cultivated.

This paper is a review article which presents brief historical information about natural dyes in different historical periods in Egypt. This information will assist archaeologists, dyers, artists and conservators who seek information about ancient dyes in Egypt. For example, the data will help conservators in choosing natural dyes that can be used in producing new models of dyed textile samples that simulate the original historical ones. These models of textile samples can be used as experimental samples in conservation research and training of young conservators. Also, this information can be used by technologists to conduct comparison studies on the technology of natural dyes in ancient Egypt. The dyes are presented according to their alphabetical names in this paper. All data in this paper have been collected from references related to this topic without any changes from the researcher.

Rural Oaxaca is plagued with economic problems. There are few jobs available and ideas concerning gender often limit the work that women are able to pursue. In this chapter, we explore how rural Oaxacan women create economic opportunities. We focus on work at home that is both voluntary and remunerative, craft production, and entrepreneurial activities. We show that rural Oaxacan women are able to create unique economic niches that build upon their domestic roles and enhance the economic status of their households.

The main ingredients are soya flour, separated milk powder and oatmeal. In some mixtures vitamin concentrates are included. In theory they are admirable, but the chief objection to soup as a meal for a child is that it is difficult to get 1,000 calories into the stomach, even with a good hunk of bread. Thick soup is too filling. It is excellent for emergency use, as experience with the Ministry of Food canned thick soups has shown under “blitz” conditions. But, on bread and thick soup, a child feels full before it has eaten the 1,000 calories it is desirable to get into him. Health of children is, from all reports, whether from public, private or elementary schools, remarkably good. We were not a little worried at this time last year about the adequacy of the supply of first‐class protein for growing boys and girls. The position is now reasonably satisfactory and every effort is being made to see that what is required for development of muscle and bone shall be provided. You, Sir, have on numerous occasions emphasised your determination to see that the younger generations shall not suffer as the younger generations suffered in the last war from diet deficiencies. The spirit that has moved you to take that firm stand will be a powerful force in the post‐war period. I can foresee, and hope to live to see, the day when every child in the country shall be able to get a good nourishing meal at school if the parents so wish. There is another important aspect of this vast expansion of the school feeding programme. The proper planning of school meals is only one way in which the child will benefit. Education in the simple facts of food values will be an essential part of the school. Impressions formed in the minds of these young people will last their lifetime. That is fully recognised in America, where a big concerted drive is about to begin to put nutrition propaganda before every section of the nation. It is true that food habits of a lifetime are sometimes hard to change. Whether they are based on long‐established custom or deep‐rooted fallacies, or both, they are not readily given up by adults. No better illustration could be given than the reluctance of the mass of the people to purchase wheatmeal bread when there was a choice between that and the ordinary white loaf. On the one hand we were urged to force wheatmeal bread down the throats of the people and were assured that they would like it when they came to understand that it was good for them. At the other extreme we were emphatically told that the public actively disliked a dark loaf. My own impression, from a close study of the matter, is that the majority of people are “conditioned,” to use a much overworked word, to white bread and give little thought to other variety. They are certainly apathetic to any appeals based on food values. Most people go into a shop, ask for a loaf of bread, get a white one, as has always been the case unless brown were specifically asked for, and give no more thought to the matter. A striking example of this indifference has been provided recently in America, where there has been extensive commercial development of the manufacture of white flour “fortified” by additions of synthetic vitamins. Large‐scale production has been in progress for about a year. At first the public, stimulated by a vigorous publicity, bought the new type of bread. Sales rapidly mounted. That it was largely novelty rather than vitamins that sold the bread in the first instance appears to be shown by the steady fall in sales that has recently occurred. Had the public as a whole actively disliked bread that is not white, as we were so often assured, it would have been reasonable to expect a volume of protest when National Bread came into general use. No such reaction occurred. On the other hand, favourable comment has been widespread. The war‐time nutrition policy that aimed at improving the food value of bread either by use of long‐extraction flours or artificial reinforcement will certainly be reflected in post‐war developments. What line they will take is not yet clear. It is certain, I believe, that minimum requirements, at least in respect to vitamin B1, will be laid down. Whether particular methods of manufacture will be specified is another question. In this connection it is appropriate to mention that a new method of milling wheat has been devised as a result of collaboration in Canada between the Government Cereals Research Department, certain milling interests and an enthusiastic pioneer who is leading Canada's nutrition “drive,” Dr. F. Tisdall, of Toronto. This method yields a flour, as rich in vitamin B1 as an 85 per cent. wheatmeal and containing considerably more of other important nutrients of the wheat berry than the ordinary type of wheat flour. If there is a public taste in regard to the whiteness of its flour, and if it is of real significance, we have here what appears to be the perfect compromise because the new Canadian flour—to be known officially as “Canada Approved”—is truly white. In passing, I may add that to encourage the production of this type of flour in Canada the addition of synthetic vitamin B1 to white flour has been made illegal. But although we must admit a large measure of resistance in adults to new ideas about food I by no means share the view that it is always a matter of the greatest difficulty to change their food habits. Twenty years ago, perhaps even ten, a workman who openly drank a glass of milk in front of his mates would have had to face a barrage of appropriately phrased ridicule. America led the way with its encouragement of milk in factories. When the war broke out we were rapidly following her lead. Milk was being drunk in considerable and increasing volume in factories. People no longer stopped to stare if they saw a big, husky navvy drinking from a bottle of milk. We were told, when we tried to get vegetable salads into workers' canteens, to make good the loss of vitamin C which is almost unpreventable in large‐scale cooking, that the “hands” would not touch them. They didn't, when little or no effort was made to explain in simple terms what they were for or to serve them attractively. The conventional idea that salads can consist only of lettuce, cucumber and tomato and that they are only to be eaten with cold meat was hard to uproot. But, wherever canteen supervisors have taken even moderate pains to encourage people to try salads—and I am speaking of war‐time salads of shredded cabbage, grated carrot, potatoes, etc.—there has been a record of success. Of course, everything depends on who runs the canteen. In one factory in London it was found not only possible, but a simple task, to make a midday meal of the “Oslo” type popular in summer months, even with men doing relatively heavy work. The serving of a helping of vegetable salad as part of the meal has proved a success in a number of communal restaurants. It is invariably eaten and most people like the innovation. If it were offered as a separate item relatively few would ask for it, merely because they are unaccustomed to do so. This small helping of fresh vegetables is of very great nutritional importance. Large‐scale cooking in restaurant kitchens involves serious losses of vitamin C. Some are caused by vegetables being prepared and left soaking many hours before they are cooked, sometimes overnight. Even more serious losses occur during cooking. Finally, cooked vegetables which have to be kept hot for several hours suffer a further serious reduction in the amount of ascorbic acid. The result is that instead of providing at least 25 mg. of vitamin C, as we would like it to do, an ordinary canteen meal may contain no more than 5·20 mg., particularly in winter months. It is all very well for the nutritional expert to tell us that by taking certain precautions and modifying the methods of cooking vegetables a large proportion of this loss can be prevented. The hard fact is that it is exceedingly difficult, sometimes quite impracticable, to change the organisation and routine of a large kitchen. We know of no means of preventing loss of C when cooked vegetables are kept hot in insulated containers, as is frequently necessary. In four hours the ascorbic acid content of a helping of cooked potatoes can fall from about 6 mg. to 2 mg., and that of one of “greens” from 25 mg. to 10 mg.; losses, that is, of the order of 60 per cent. The small helping of vegetable salad overcomes the difficulty. We have found that there is relatively a small loss when fresh vegetables are shredded or grated. A helping of about 3–4 ozs. of mixed chopped cabbage, carrot, turnip and beetroot gives from 20 to 40 mg. of vitamin C: an amount ample for the average person's daily need. We are trying very hard through the medium of propaganda by the Ministry of Food and Board of Education to make the people salad‐conscious; in the hope that salads will become an accepted part of the daily meals of an increasing number of families, schools, institutions and hospitals. If the movement really gains good ground during the war period, when the choice is so restricted, it should spread rapidly when normal times come and the green‐grocer's shops show once again the rich variety of produce from home and overseas. It has been a hard, uphill fight to make “the man in the street” believe that garden vegetables are a good substitute for fruit, in the nutritional sense. I think we have made good progress, but there are many still unconverted. It is important that the truth of this matter should be widely known. Of the fruits we ate in ordinary times only oranges, grapefruit, blackcurrants, redcurrants, gooseberries and strawberries are particularly good sources of C. Apples, pears, bananas, cherries and plums are relatively poor in this respect. When most of these fruits are unobtainable, as at present, it is important to know that we can easily obtain our vitamin C from cabbage and sprouts, cauliflower and broccoli. We recently published, in collaboration with Dr. H. V. Taylor, of the Ministry of Agriculture, tables showing that a well‐cultivated allotment of the regulation size of ten rods, a mere 300 sq. yards, will provide all the vitamin C required for a family of four during each month of the year, even after liberal allowances for wastage and cooking losses. Moreover, the same crops will provide no less than half the vitamin A required by a family of that size. No stronger evidence of the immense value of an allotment could be produced. It will be a thousand pities if every effort is not made to sustain the allotment movement to the greatest possible extent after the war. After the last war the area cultivated in this manner fell rapidly as parks, building sites and other grounds were taken back for their original purpose. Of necessity, much land will have to be given up when peace comes again, but if our post‐war world, is, as Sir Stafford Cripps remarked on Sunday last, to be “consciously planned for better living conditions,” the immense national importance of allotments must not be ignored as it was in the “reconstruction” after 1918. Nor do I feel we should regard the British Restaurant as a temporary war‐time expedient. There will doubtless be a certain amount of agitation after the war directed towards their abolition.