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Manufacturers show a growing tendency to remove the skin from all fruits and vegetables before drying. Because of custom or the type of skin, some kinds, notably prunes and apricots, however, are rarely peeled. Peeling may be done by hand or by specially designed machines. Many types of knives, with straight, curved or guarded blades, and hand‐operated cutting machines are obtainable for peeling, trimming, coring and otherwise preparing the material to be dried. Machines for peeling and coring both apples and pears in one operation are available. Friction or rotary mechanical peelers are particularly well suited for handling roots and tubers. All peelers of this type depend upon the rasping effect of rough surfaces of cement, corundum, etc., forming some part of the lining of the peeler, when the product is rotated rapidly within the cylinder by a moving bottom. The material is introduced at the top and discharged by a side door. These machines are usually equipped with water sprays, which wash off the dirt and the particles of skin removed by the peeler. Other types make use of an open flame which chars the skin so that it can be brushed or washed off. Several types of lye peelers are available. All depend upon immersion in or spraying with hot (190°–200° F.) lye solution. The length of treatment must be determined for each batch of fruit. It should be long enough to permit the ready removal of skin by water sprays or by rubbing, but must not injure the flesh of the product being peeled. Following the peeling, the fruit or vegetable must be inspected and all remaining skin removed with trimming knives, especially adapted to different products. Lye is used to check the skins of prunes and grapes in order to facilitate drying. The fruit is in contact with the hot lye solution long enough to break the skin by many minute fissures or checks, but not long enough to loosen it. The concentration and temperature of the lye bath are similar to those for lye peeling. After the lye treatment the fruit is carefully washed to remove all traces of the lye bath before further processing. Fruits are sliced, cubed, shredded, or left whole. Vegetables are sliced, cubed, shredded, or chipped. The cutting is done by hand or by some one of the numerous machines on the market. Some of the machines consist essentially of rotating knives or cutting surfaces operated by hand or by power. In others the cutting surfaces are stationary and the product is forced against the blades. Special machines for cutting beans are made. In the most satisfactory type of cubing machine the slices are cut, carried to a die, and forced through by a plunger. Manufacturers find it desirable to pit or seed stone fruits, as pitted or seeded fruits dry more rapidly and sell more readily than those from which the pits or seeds are not removed. Machines for pitting, seeding and paring most fruits are for sale by food‐machinery manufacturers, but the greater part of dried fruits are pitted by hand. After the raw material is prepared in the desired form, no time should elapse before traying and subsequent treatments preliminary to its being placed in the drier. No definite rule can be given for determining the quantity of material to be placed on a unit area of tray surface. Experience will soon show the operators how much will insure even, rapid drying. Many of the larger fruits must be trayed only one layer deep. Overloading trays must be avoided. Trays should be light but capable of withstanding strain, and they should permit a maximum exposure of the materials. Trays of the type most often seen have a spreading surface formed either of wire screen or wooden slats held firmly in a narrow but rigid wooden or metal frame. Many of the trays now in use have been employed in sun or other drying. If new trays are made, the one‐man tray, about 2½ to 3 feet square, will be found to be the most convenient. Wooden‐slat trays can be more cheaply constructed than wire‐screen trays, but they have a high rate of upkeep. These trays, however, are not affected by sulphur fumes or fruit acids, for which reason they are preferred for most fruits. The trucks for conveying loaded trays are of two general types. In one a skeleton frame is provided with cleats, upon which the trays rest. The cleats are from 2 to 4 inches from centre to centre above one another. These trucks are made of various combinations of wood or angle iron. The other, which may be called the stack type, has a low floor supported by wheels 3 to 5 inches in diameter. The trays are piled or stacked one above the other, and the desired space between them is maintained by the raised sides of the trays. Various alterations may be made for convenience in handling and loading. The original method of preparing fruits and vegetables for drying consisted in washing, peeling when desirable, cutting, and traying. By this method most dark‐coloured materials made fairly presentable dried foods, but light‐coloured fruits and vegetables did not. The attempt to overcome this difficulty led to the introduction of blanching, or processing, and sulphuring. The blanching, or processing, agent is usually steam or hot water, which helps the product to retain its natural colour. In the steam treatment the material is subjected to live steam for the required period. In blanching by hot water, the temperature is maintained at 190° F. to the boiling point, depending on the material being treated. As a rule, steam blanching is preferred to blanching in liquid, because the loss of soluble constituents of the food is less, a better flavoured product results, and the use of steam is ordinarily more convenient. Light‐coloured fruits (apricots, peaches, pears, and at times grapes and figs) are sulphured in order to prevent discolouration during and after drying and to facilitate drying. Sulphuring plasmolyzes the cells and makes permeable the semipermeable cell membrane, thus facilitating the diffusion of water from the interior to the surface. When the general plan of operation makes it desirable, the fruit on trays is sulphured in an enclosed chamber, provided with an entrance for the sulphur gas and an exit for a draught. The chamber is usually large enough to hold one to two loaded trucks. Preferably the sulphur is burned in shallow pans stacked one above the other in zigzag formation. This method gives a large quantity of sulphur dioxide in a comparatively short time. Sometimes a sulphur stove is placed outside the chamber and the sulphur fumes are carried into the chamber by flues. Sulphuring should always be as light as possible to accomplish the desired results. The type of equipment best adapted to any particular use depends upon several factors. If the products are to be dried for home or farm use, then the equipment should be as simple as possible. If the dried material is to be prepared in large quantities for sale to the public, then the type of equipment will depend to a great extent upon the nature of the product desired. To meet these needs many devices have been originated and patented, so that all phases of drying are well covered. Materials can be dried more rapidly and at lower temperatures in vacuum than at atmospheric pressure. Such foods as are extremely susceptible to damage by heat are more safely dried in vacuum. However, vacuum driers are seldom used in large‐scale operations on the usual commercial grades of dehydrated fruits and vegetables. The apparatus is too expensive and usually the advantages gained are not sufficient to compensate for the added cost of equipment and operation. Enzymes are not inactivated by evaporation alone, and it will be found desirable in many cases to inactivate them by blanching or by other means if vacuum drying is used.

The purpose of this research is to develop an environmentally friendly antimicrobial dyeing of cotton fabric from the root of Euclea racemosa. Textile phytochemical finishing is in high demand worldwide because of its low toxicity, low pollution, ease of availability, renewability, pharmacological effects and non-carcinogenic properties, as well as its multifunctionality, rapid process stages and potential health benefit.

The cotton fabric was dyed with aqueous extracts of Euclea racemosa root dyes. Dyes were extracted for 20 min at pH 7.43 at room and boiling temperatures with material-to-liquor ratios (MLRs) of 1:5, 1:10, 1:15 and 1:20, altering one variable at a time, and the cotton fabric was colored using a post-mordanting procedure at 50°C with an MLR of 1:20. Using a properly cleaned Petri plate, the colored samples were tested in vitro for antibacterial activity. A spectrophotometer was used to assess color strength and shade depth, as well as wash fastness and annual rubbing fastness tests for both wet and dry.

L* = 36.29, a* = 58.56, b* = 32.46 and K/S = 0.51 were the CIELAB values for dye extracted at boiling temperature. L* = 47.14, a* = 42.23, b* = 49.61 and K/S = 0.38 were the CIELAB values for dye extracted at room temperature. The wash and rubbing fastness of the dyed samples were outstanding and the dyed cotton fabrics were found antibacterial against Gram-negative bacteria Escherichia coli.

Dyes derived from the E. racemosa root could be used to develop a new antibacterial cotton fabric dye.

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.

Attention has often been directed to the fact that much unwrapped bread becomes dangerously dirty by the time it is consumed, and there is now a considerable body of opinion in favour of making the wrapping compulsory. The hygienic advantages of this are unquestionable; for although a loaf may be of a high standard of purity on leaving the factory, there are ways by which much contamination may occur subsequently. There are dangers, beyond the control of Sanitary Authorities, arising from contamination by dirty hands, clothing, baskets and carts; the dust from streets, doorsteps and window sills; and from the organisms of disease harboured by apparently healthy “carriers” of infection; and very often pieces of crust are given to little children to bite upon, in order to aid the development of their teeth and gums.—Dr. G. H. Dart (the Medical Officer of Health for Hackney) has recently emphasised the fact that there is much typhoid and paratyphoid fever, and other disturbances of health, which occur without any source of infection being traced; and he maintains that it is a reasonable assumption that some of this infection results from our failure to adopt measures for safeguarding the cleanliness of bread. From a small investigation upon five loaves, it was found recently that four of them yielded bacteriological results that testified to gross contamination—a number of streptocococci, staphylococci and coliform organisms having been found upon each of the four loaves. It will not be disputed that the value of the precautions adopted, even in the most hygienic bakeries, may be greatly discounted by the failure to protect the bread from contamination in its subsequent passage to the consumer; and it seems—to say the least of it—inconsistent, to provide against the contamination of meat (as by the 1924 Meat Regulations)—an article of food which is cooked before consumption—and to ignore the contamination of bread which is eaten as delivered to the purchaser. That bread can be wrapped without loss of flavour and at little cost has been demonstrated in America and by some bakers in England. In a useful paper by C. H. F. Fuller, B.Sc, A.I.C., Research Laboratories, Messrs. J. Lyons & Co., Ltd., which appeared in the last issue of the Journal of the Royal Sanitary Institute, attention is drawn to the fact that it is possible, by the employment of a waxed paper wrapping, largely to eliminate moisture loss from the loaf, and thus to secure a loaf which remains longer in a palatable condition, owing to delay in the onset of staling; but before wrapping, the loaf must be cooled until the centre attains a temperature not far beyond that of the outside air, in order to avoid the occurrence of “sweating,” i.e., deposition of moisture on the crust and inside of the wrapper. He also refutes the contention that the wrapping of bread necessarily leads to the absorption of foreign flavours from the wax or paper; for trouble from these causes is avoidable if suitable measures are adopted. Indeed, the whole subject of bread wrapping has been submitted to a close examination by a number of investigators; and in general there is agreement among them that no deleterious effect upon the quality of the bread results, and that the public would benefit from the resulting improvement in cleanliness, freshness and palatability. The hygienic considerations in reference to bread apply also to all exposed food which is not washed, peeled, cooked or treated in same way which removes dirt or renders it safe for consumption. The obvious remedy for the dangers involved by our neglect is to press for legal powers to enforce the necessary precautions and to educate public opinion upon the need for these.

The investigation here reported was undertaken to determine certain physical principles and their application to dehydration problems in general. The project was not carried to the point where it was possible to consider the modifications necessary for the different varieties of fruits and vegetables. Factors leading to the deterioration of dehydrated products and the relation which the condition of the fresh material may bear to this deterioration are important phases of the problem not here considered. Spoilage of raw food is due principally to the growth of moulds and bacteria. This growth does not occur when the soluble solids are sufficiently concentrated through the reduction, by drying or by other means, of the water present in foods. Even if they are not killed, the moulds and bacteria remain dormant and harmless in the absence of a suitable medium for their growth. Changes in composition, flavour and appearance, however, may also be brought about by the action of the enzymes present in practically all foodstuffs. As these natural catalytic bodies are not always inactivated by the treatment which stops mould and bacterial action they must be considered in working out methods of dehydration. The outstanding advantage of drying as a method of preserving foods is that the weight and bulk of the products are greatly reduced, thus making possible economy in storage and transportation. The production cost of dehydration compares favourably with that of canning. Dried fruits and vegetables are almost as convenient for use in the home as the fresh products. They need no peeling or other preliminary treatment, and soaking and cooking can often be combined. Only the quantity required need be used when the package is opened; the rest will keep in good condition for a reasonable time. “Dried,” “sun‐dried,” “evaporated” and “dehydrated” are the terms most commonly used to describe dried products. Dried indicates drying by any means; sun‐dried indicates drying without artificial heat; and evaporated implies the use of artificial heat. Evaporated refers more particularly to the use of artificial heat in driers depending for their air circulation on natural draught, while dehydrated implies mechanical circulation of artificial heat. The commercial dehydration of fruits has reached a more advanced stage of development than has the commercial dehydration of vegetables, owing largely to the fact that the public is familiar with sun‐dried and evaporated fruits, whereas it knows comparatively little about dried vegetables. During the World War 8,905,158 lbs. of dehydrated vegetables, divided as follows, were shipped to the United States Army overseas: Potatoes, 6,437,430lbs.; onions, 336,780; carrots, 214,724; turnips, 56,224; and soup mixture, 1,860,000. In the years immediately following 1919 the drying of vegetables declined rapidly, and for the last 10 years or more production has been compartively small. To be successful, a dehydration plant must be built where fresh materials are plentiful and reasonable in price. A diversity of products makes possible an operating season long enough to keep the overhead expenses down to the minimum. The products dried, however, should be limited to those for which a ready market exists. The only satisfactory method of operating is to contract for a sufficient acreage to take care of the needs of a plant at a price which will permit both the grower and the drier to make a profit. Material to be dried must be carefully sorted so as to be free of mould, decay and other defects that would lower the grade of the finished product. The stone fruits (apricots, peaches, cherries and plums) must be sufficiently firm to permit mechanical pitting without tearing. Where they are prepared by manual labour they must not be so soft as to stick to the trays. Apples and pears must not be so soft as to crush in the coring and peeling machines. Berries, cranberries and grapes are usually dried whole. Fruit that needs trimming must be avoided, as it not only adds to the cost of operation, but also lowers the grade of the final product. Vegetables, such as beans (snap), cabbage, carrots, celery, corn, parsnips, potatoes, pumpkin, spinach, squash and turnips, are sliced, shredded, diced or cut in desired pieces before drying. Dehydration does not improve the quality of fresh fruits or vegetables, nor does it provide for the satisfactory use of unsound products. At best the process can only conserve the original constituents of the foods, minus replaceable water. Careful handling reduces labour and waste. Bruised tissue is especially susceptible to discolouration and decay. Individual pieces prepared from good stock are more uniform and attractive than those from heavily trimmed stock. Raw materials should be as carefully washed and cleaned for dehydration as for table use. Much of the washing machinery used in canning is suitable for use in dehydration plants. A rotary cylindrical washer equipped with a water‐spraying system is very satisfactory for washing many types of products. Soft or easily broken fruits and vegetables may be washed by passing the trayed material between several sprays of cold water. The segregation of fresh fruits and vegetables according to size facilitates both the preparatory handling and the drying. One type of grader consists of a perforated metal plate, 3 by 10 feet, or larger. The perforations are in sections of varying size, and the plate is inclined and mechanically agitated in order to insure an even flow of the material in one direction. The product is separated according to size by being passed through the perforations. Perforated plates are also used in stacks. Several plates, each stamped with holes of a uniform size, the holes varying in size with each plate, are set one above the other, with 6 inches or more between plates. They are arranged so that the holes are progressively smaller from top to bottom. Another grader sorts out easily rolling materials according to diameter. As a mechanically driven cable rolls the materials along an opening that increases in width, the product falls through and is collected according to size. A grader based on the same principle passes the product down a chute the floor of which consists of rollers placed at increasingly greater distances apart. As the product rolls along the chute it is separated in progression according to size.

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.

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

Few will complain that 1974 has not been an eventful year; in a number of significant respects, it has made history. Local Government and National Health Services reorganizations are such events. This is indeed the day of the extra‐large authority, massive monoliths for central administration, metropolitan conurbations for regional control, district councils corresponding to the large authorities of other days; and in a sense, it is not local government any more. As in other fields, the “big batallions” acquire greater collective power than the total sum of the smaller units, can wield it more effectively, even ruthlessly, but rarely appearing to take into account the masses of little people, the quiet people, who cannot make themselves heard. As expected, new names of authorities are replacing the old; new titles for departments and officers, ambitious and high‐sounding; a little grandiose for the tongues of ordinary folk. Another history‐making event of 1974, in the nature of a departmental transfer but highly significant for the course of future events as far as work in the field is concerned, was handing over of the personal health services—health of expectant mothers, babies, children, domiciliary midwifery, the school health services and their mainly medical and nursing personnel—from local health authorities to the newly created area health authorities. The public health departments over fifty years and more had created them, built them up into the highly efficient services they are. If anything can be learned from the past, new authorities are always more expensive than those they replace; they spend freely and are lavish with their accommodation and furnishings. In their first few months of existence, the new bodies have proved they are no exception. News of their meetings and activities in many areas is now scanty; even local newspapers which usually thrive on Council news—or quarrels—seem to have been caught on the wrong foot, especially in the small towns now merged into larger units. The public are relatively uninformed, but this doubtless will soon be rectified.

The purpose of this study is to investigate the effect of lemon juice on the survival of Salmonella Enteritidis and Escherichia coli in cig kofte (raw meatball).

Cig kofte samples were inoculated one by one with both bacteria at high inoculum levels and were treated with different doses of fresh lemon juice (2, 5, 10 and 15 ml) for 10 seconds, 30 seconds, and 1, 5, 15, 30 and 60 minutes.

Treatments of lemon juice for different exposure times caused reduction ranging between 0.1 and 1.7 log CFU/g for Salmonella Enteritidis and 0.1 and 2.1 log CFU/g for E.coli. Results showed that lemon juice caused slight decrease in Salmonella Enteritidis and E.coli as an immediate inhibitor, but this effect increased with concentration and time.

This is a research study to provide information on the effectiveness of lemon juice which is squeezed generally before eating cig kofte, on the presence of the surface flora to strengthen the hygienic quality of the product. Inactivation effect of lemon juice on Salmonella Enteritidis and E.coli may give a practical and easy way of providing food safety for cig kofte.

Scurvy was at one time one of the most wide‐spread diseases, especially among seamen on long voyages. Little was known about the causes or treatment of the disease, but in 1753 James Lind showed that it could be prevented and cured by eating fresh fruits and vegetables. Captain Cook in his voyages made full use of this discovery to keep his crew in good health. In 1842, Budd suggested that scurvy was the result of ‘abstinence from vegetables and fruits’, but it was not until 1907 that this was demonstrated in practice, when Hoist and Frölich produced experimental scurvy in guinea pigs by using a restricted diet. In 1932 the active factor, ascorbic acid, was isolated in a pure form from lemons by Zilva and found to be identical with a compound obtained by Szent‐Györgyi from cabbages and adrenal glands in 1928. Finally, Haworth and Hirst identified the structure of ascorbic acid or vitamin C, which was synthesised in the same year by Reichstein and others.