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Dimensional accuracy analysis of wax model created by room temperature vulcanization (RTV) silicone rubber molding to be used in investment casting is presented. The purpose of this paper is to discuss the effective parameters of dimensional accuracy in RTV tooling technique.

After producing a pattern by stereolithography (SLA) and then creating the RTV silicone rubber mold by the SLA pattern, dimensional accuracy of wax models produced by RTV tool are analyzed. Design of experiments (DOE) using the Taguchi approach is used for analysis and determination of optimum condition.

Experiments show that the dimensional accuracy in RTV technique is as accurate as in traditional molding. Hence, RTV tooling technique can be used in investment casting. Using Taguchi approach based on DOE, it was realized that the optimum condition to achieve acceptable accuracy is 35°C for mold temperature, 85°C for wax temperature, and −0.5 barG for vacuum pressure.

RTV silicone rubber mold is a useful alternative of metallic mold to produce wax patterns for investment casting. It has benefits such as reduction in production lead‐time and cost, compared with traditional metallic mold.

A case study for research of dimensional accuracy of wax patterns created by RTV silicone rubber mold had not been attempted as such. In addition to reduction in production lead‐time and cost, the dimensional accuracy of wax patterns using RTV tooling technique are as accurate as in traditional technique.

The purpose of this paper is to determine the physicochemical properties of oil produced from Roselle seeds.

The oil was produced from the seeds by mechanical expression and the physicochemical properties of the oil determined using the AOAC methods.

The values of the physicochemical properties of oil from Roselle seed are saponification value 126.2, iodine value 111.2, viscosity 22.5 cp, refractive index 1.4472 and specific gravity 0.9558. The peroxide value varied between 6.0‐9.3 and 5.9‐9.0; and free fatty acid, 0.435‐2.300 and 0.510‐3.311 for fine and coarse samples, respectively. These values compared favourably with standard values, indicating that the oil extracted is edible.

The properties are useful in determining the suitability of the oil from the Roselle seeds as edible oil or for other industrial purposes.

Extraction and purification of Hypophthalmichthys molitrix fish oil by urea complex formation were made at −5, +1 and +5 ^○C, respectively. Omega‐3 polyunsaturated fatty acids (PUFA) have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia. Starting with the hypothesis that the observed low cardiovascular morality could be related to marine diet, which contains omega‐3 PUFA.

Fish oil was extracted by Bligh and Dyer method from the muscle tissue and after, the PUFA concentrates produced by urea complexation and the oil samples were stored at −70 ^○C. The observed results show that the rate of omega‐3 extraction has been increased while saturated and long chain monosaturated fatty acids decreased during this process.

Eicosapentaenoic acid (EPA) has a higher tendency to form urea adducts than the other two major n‐3 PUFAs, especially at low temperatures. The optimum temperature for maximum recovery of EPA is about 1 ^○C. The amount of extracted omega‐3 in H. molitrix oil were 20.58 per cent wt of total extracted oil and by subsequent purification increased to 68 per cent wt at 1 ^○C, 36.82 per cent wt at +5 ^○C and 22.53 per cent wt at −5 ^○C of total extracted oil.

Omega‐3 PUFA have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia. Starting with the hypothesis that the observed low cardiovascular morality could be related to marine diet, which contains omega‐3 PUFA. In order to reduce the risk of cardiovascular diseases, emphasis has now been placed on the increased consumption of fish and fish products which are rich in PUFA.

The amount of extracted omega‐3 in H. molitrix oil were 20.58 per cent wt of total extracted oil and by subsequent purification increased to 68 per cent wt at 1 ^○C, 36.82 per cent wt at +5 ^○C and 22.53 per cent wt at −5 ^○C of total extracted oil. Due to the low price of H. molitrix in comparison to other ocean fish sources, as well as, its availability in all seasons, higher level of ω3‐fatty acids, H. molitrix species has a good potential for ω3‐fatty acids production by extraction and subsequent purification.

The animal and vegetable oils, fats, and waxes provide vital raw materials for a large number of industries. Soap, paint, foodstuffs, textiles, leather, and linoleum are but a few of the diversity of products which employ one or more of this large class of natural bodies.

Previous articles in this series appeared in our April, May and July issues and covered General Composition and Classification, Identification, and Testing respectively. This series will be enlarged to include more detailed information and will shortly be published in booklet form.

Fruits and vegetables, being good source of energy, health promoting and protecting compounds with unique taste and flavor, are attracting consumers since ages. These horticultural produces start deterioration just after harvest; therefore, their proper storage is must during transportation and storage to retain maximum quality parameters and for good market value. Best storage conditions are required to prevent growth of micro flora and to maintain the nutritional values of harvested produce. Retailers and processors in every corner of world want to move toward the cheaper ways to increase the shelf life and texture of horticultural crops for better consumer preference. The purpose of this paper is to make consumers and researchers aware about different post harvest malpractices in fresh fruits and vegetables.

Lot of chemicals like colors, artificial ripening agents, sweeteners and waxes are applied on surface of horticulture produce to siphon off money from consumers, and these have adverse health effects directly or indirectly. Various regulatory agencies have launched various programs, acts and laws for monitoring and avoiding such unhealthy ways. Regulatory bodies launched training programs also for the food handlers and consumers to ensure the food safety from farm to fork.

This paper will throw light on different malpractices followed by retailers to manipulate the quality which causes adverse health effects and to create consumer awareness regarding such malpractices.

The paper emphasizes on current malpractices followed by retailers to mislead the consumers about fruits’ and vegetable’ quality by using sweeteners, colors and other chemical. On prolonged consumption, such substances lead to major health issues such as attention disorder.

The long controversy that has waxed furiously around the implementation of the EEC Directives on the inspection of poultry meat and hygiene standards to be observed in poultry slaughterhouses, cutting‐up premises, &c, appears to be resolved at last. (The Prayer lodged against the Regulations when they were formally laid before Parliament just before the summer recess, which meant they would have to be debated when the House reassembled, could have resulted in some delay to the early operative dates, but little chance of the main proposals being changed.) The controversy began as soon as the EEC draft directive was published and has continued from the Directive of 1971 with 1975 amendments. There has been long and painstaking study of problems by the Ministry with all interested parties; enforcement was not the least of these. The expansion and growth of the poultry meat industry in the past decade has been tremendous and the constitution of what is virtually a new service, within the framework of general food inspection, was inevitable. None will question the need for efficient inspection or improved and higher standards of hygiene, but the extent of the organization in the first and the enormous cost of structural and other alterations to premises in the second, were seen as formidable tasks, and costly. The execution and enforcement of the new Regulations is assigned to local authorities (District, Metropolitan and London Borough Councils), who are empowered to make charges for inspection, licences, etc., to recoup the full costs of administration. The Government had previously promised that the cost of this new service, which when fully operative, will be significant, would not fall upon the already over‐burdened economies of local authorities. The figure of a penny per bird is given; in those areas with very large poultry processing plants, with annual outputs counted in millions of birds, this levy should adequately cover costs of enforcing the Regulations, but there are many areas with only one of a few small concerns with annual killings of perhaps no more than 200,000 birds—this much we know from perusing annual health reports received at the offices of this Journal—and the returns from charges will certainly be inadequate to cover the cost of extra staff. The Regulations require the appointment of “official veterinary surgeons” and “poultry meat inspectors”, both new to local government.

At the passing of the Fair Trading Act, 1973, and the setting up of a Consumer Protection Service with an Office of Fair Trading under a Director‐General, few could have visualized this comprehensive machinery devised to protect the mainly economic interests of consumers could be used to further the efforts of local enforcement officers and authorities in the field of purity and quality control of food and of food hygiene in particular. This, however, is precisely the effect of a recent initiative under Sect. 34 of the Act, reported elsewhere in the BFJ, taken by the Director‐General in securing from a company operating a large group of restaurants a written undertaking, as prescribed by the Section, that it would improve its standards of hygiene; the company had ten convictions for hygiene contraventions over a period of six years.

THE most common animal fats include materials such as tallow, mutton, and lard oil. Their compositions and properties vary with the particular rendering or recovery methods, type and extent of refinement. Waxes such as beeswax may be considered a special classification of animal fats.

Viewing the last dying embers of 1984, the Orwel‐lian year of Big Brother and some of its not‐so‐far off the mark predictions, the unemployment which one cannot help feeling is more apparent than real, it is hardly surprising that the subject of Poverty or the so‐called Poverty arise. The real poverty of undernourished children, soup kitchens, children suffering at Christmas, hungry children ravenously consuming free school meals has not, even now, returned.