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In the first article in this series, the author dealt with general classification and composition of oils, fats and waxes, and this went on to discuss the properties of drying and non‐drying vegetable oils. In this second part, the properties of animal and fish oils, fats and waxes will be considered.

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.

Parts 1 and 2 in this series appeared in our April and May issues respectively, and dealt with general composition and properties of these oils, fats and waxes. The next and final part will cover testing.

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.

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.

Oleochemicals can be made from the components of renewable animal, marine and vegetable oils and fats. This oleochemical group of products is a large one, comprising fatty acids, glycerol and numerous derivatives of these including fatty alcohols, fatty esters, and nitrogen‐, phosphorus‐and sulphur‐containing materials. Polyoxyalkylated end products from the above, from heavy metal and water‐soluble soaps, epoxidised chemicals, polymer components, and the quarternary ammonium compounds are found. The oleochemicals of interest to the lubricants manufacturer are those which function in some specific manner. Anti‐corrosive, anti‐oxidant, anti‐squawk, anti‐stick, anti‐sludge, anti‐wear detergent, dispersant and oiliness agents, pour point depressants and viscosity modifying materials, are examples.

Although this series was concluded in our August issue, by the following further contribution has been received from Mr. Griffiths. This article can be read independently from the previous four, but nevertheless, we think should be included in the series.

If more was known of this, our oldest Colony, and its famous fisheries, public interest would now, at the present crisis, be turned to it.

In order to evaluate the effectiveness of the corrosion prevention practices applied to agricultural equipment manufactured and used in Nigeria, it is necessary to identify the various corrosion prevention methods and specify the contribution and the efficiency of each method to corrosion protection. This paper outlines the basic corrosion prevention methods used in practice and attempts to evaluate the effectiveness of their use in relation to agricultural service in Nigeria. The results of this study indicated the use of oils, fats, waxes and lubricants on metal parts, spraying with gasoline on corrosion‐sensitive parts constituted the majority of applied corrosion protection in industries where the equipment is manufactured and/or used. The study concluded by giving practical recommendations that are essential for improving corrosion prevention in the Nigerian agricultural industry.

The purpose of this study is to compare the oxidative stability of non‐hydrogenated cottonseed oil with that of the partially hydrogenated oils commonly used as a deep‐fat frying medium by the restaurant industry when used to prepare French fries in order to reduce trans‐fatty acids.

Stability characteristics of non‐hydrogenated cottonseed oil and two hydrogenated oils, canola and soybean, were evaluated in deep‐fat frying applications. French fries were analyzed for total polar compounds, and the oils were analyzed for iodine, peroxide, p‐anisidine and totox values, and free fatty acids.

Canola and soybean oil had significantly lower iodine values than cottonseed oil. Free fatty acid values were not significantly different among the oils (0.256 per cent oleic acid). Initially cottonseed oil had higher peroxide, p‐anisidine, and totox values compared with canola and soybean oil. However, as days of frying increased, values trended closer together. Total polar compounds were similar. All oil types were comparable in terms of their stability characteristics under the conditions used in this study.

Research with additional food product and under more stressful conditions would be beneficial.

Hydrogenation increases trans‐fatty acid content. Consumption of trans‐fatty acids has been associated with increased risk of heart disease. Non‐hydrogenated cottonseed oil may be a viable alternative to popular hydrogenated oils currently used in the restaurant setting.

Restaurants are being pressured by health officials to choose healthier oil. This research article can help restaurants make an informed choice.