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The purpose of this paper is to investigate the quality of the frying oil used in restaurants, fast food establishments, and confectionary stores. The compliance of used frying oils with the quality standards as determined by the peroxide value (PV) and the total polar materials (TPMs) is investigated by analyzing 375 samples of oil.

The PV was measured according to the national standard procedure number 4179, while the TPM was determined using a Testo 270 cooking oil tester. Frying oils with a PV>5 mEq/kg and a TPM>25 percent were considered to be non-edible. For a comparison of groups, the Mann-Whitney and Spearman correlation tests were used, and p<0.05 was considered significant.

The maximum TPM and PV recorded for frying oils in fast food restaurants were 97.5 percent and 77.9 mEq/kg, respectively. The results also revealed that 60 percent of samples were non-edible according to the TPM, while 58.9 percent of the oil samples were non-edible because of the PV. TPM and PV correlated well with each other (r=0.99, p<0.001) and with oil replacement intervals (r=0.90, p<0.001). The relationship between the TPM and PV was stronger in the polynomial model than the linear model. The following equation was obtained: peroxide (mEq/kg oil)=0.0043 TPM2 (%)+0.1587 TPM (%)–0.6152.

Considering the current limitations in official supervision by health authority, on-site self-monitoring of the TPM using the Testo 270 cooking oil tester by sellers as a solution seems a new approach. Food stores, restaurants, and confectionary stores should be equipped with TPM analyzers to determine the quality of the frying oil and the timely replacement of non-edible oils.

The Department of Scientific and Industrial Research has released an account of the preparation of emergency rations in the form of dehydrated foodstuffs. These rations were designed and made when the result of a forced landing of an aircraft flying over polar regions may have to be faced. Having regard to the special circumstances for which the method described by the Department was designed it is perhaps not too much to say that it introduces as great a change in feeding the crews of airships as did Appert in feeding the crews of sailing ships a hundred and thirty‐five years ago. Appert's method did much to eliminate scurvy. This to prevent starvation and loss of life which the accounts of Polar expeditions have too often recorded. Dried fruits and dried vegetables have long been known and used. Milk powder and egg powder are now as well known. If these and tinned foods be regarded as ordinary rations they are too heavy and too bulky to be of use in an emergency such as may arise when a Polar flight ends in an unpremeditated grounding and the crew are left in a Polar desert to make the best they can of the conditions. It will be remembered that in May last the “Aries,” a British Lancaster airship, made a trip of some 17,000 miles. Much of this trip was in the Polar regions. The g eographical North Pole was visited and in the return journey the true position of the magnetic North Pole was ascertained in a 4,000 mile non‐stop return journey from White Horse, Yukon, to Shrewsbury. In view of possibilities an emergency ration had to be designed in which most of the food was in the form of hydrostatically compressed blocks of compounded and dehydrated foods. The compression reducing bulk; dehydration, weight; compounding ensuring variety. The rations so prepared had to be sufficient to feed nine men for twenty‐eight days. An account of the rations so prepared forms the subject of the report issued by the Department. These blocks consist of mixtures of dehydrated foods with added sweetening and flavouring materials where appropriate, so that each is a ready‐made meal requiring only the addition of water. They are fabricated into tablets of standard size (usually 2in. by 2in. by 0·9in.). They need only to be wrapped in high grade waxed films or papers and their standard size facilitates the assembly of mixed rations whilst very little space is wasted as compared for instance with circular cans. They are made by one of two processes—those containing dried foods of large particle size such as dehydrated meat or vegetables are made by compressing the mixture in a hydraulic press. The pressed block can be broken down easily in the hand. Where the particle size of the material is much finer, as with spray dried powders such as milk or egg, such compressed blocks would be very difficult to crumble, and furthermore lumps escaping crumbling would remain as unreconstituted lumps and mar the smoothness of the product. Thus they are prepared by casting the mixture hot into moulds with added molten fat. The block can be dissolved by boiling water. Many of the blocks containing milk powder may be eaten as sweets. Four kinds of menus from these blocks were prepared to relieve monotony of diet. Details of these are given in the report for four days. The total number of calories for each day ranges from 3,550 to 3,380. The weight of food per man in grammes from 715 to 704. Fat in grammes 213 to 177. Percentage of fat 30 to 25. The computed total nett weight was 393 lbs. Rations for two days can be packed in a standard four‐gallon can—gas packed if necessary—as a master container. Fourteen such cans would be necessary. These, together with immediate wrappings, would make a gross weight of 435 lbs. A most important consideration is weight. It is pointed out that the water extracted during the dehydration process would fill another seventeen cans! If light metal alloys instead of tin plate were used for the master cans a reduction of weight would be possible, but even a total weight of 435 lbs. is “very modest” compared with the weight of most emergency rations, even when the weight of master containers is excluded for the rations as drawn up provide for each man three normal meals per day. The Department refers to the theoretical aspect of the provision of a calorific level of 3,400 per day, with a total weight of 704 gms. per man. If the diet were made up of pure carbohydrate, pure fat and pure protein alone, then, using the factors 4·9 and 4 respectively as the number of calories derived from each gramme of food, a diet containing 25 per cent. fat would have an overall calorific value of 5·25 Cals/gm. a diet giving 3,400 calories, as in Day 3, would therefore weigh 647 gms. This is an absolute minimum below which it would be impossible to go. This figure takes no account of the residual water content of dehydrated foods of salt or minerals or roughage. The weight of 715 gms. achieved in practice includes, in addition to water and roughage, some 8 gms. of salt and 13 gms. of tea. It is therefore considered that, for a ration which gives three normal meals a day, it would be virtually impossible with the materials available at present to reduce the weight of the ration further. It may be added that a stove has been designed to burn motor spirit should it be possible to salvage any after a forced landing. It is considered that this type of food may be of great value for future polar expeditions. This is undoubtedly true whether aeroplanes be used as part of the equipment or not. It may be permissible to suggest that rations such as these would prove useful in land expeditions at a pinch. While in the case of a ship having to be abandoned in mid ocean the crew's chance of survival would obviously be bettered by having a supply of such concentrated rations in the ship's boats.

This research aims to evaluate the antioxidant potential of oregano extract (OE), as well as its isolated and synergistic effect when applied to soybean oil (SO) under thermal oxidation.

In order to determine the antioxidant activity of oregano extract and its synergistic effect with tert‐butylhydroquinone (TBHQ), thermal oxidation was performed using the following treatments: SO, SO with 50 mg/kg of TBHQ, SO with 3,000 mg/kg of OE, and SO with 3,000 mg/kg of oregano extract and 50 mg/kg of TBHQ (mixture). The treatments underwent heating at 180°C for 20 hours, and analyses of oxidative stability, total polar compounds, tocopherols and fatty acids composition were performed. The results obtained were subjected to analysis of variance and Tukey test for averages at 5 percent, using the program ESTAT version 2.0.

Considering the results of antioxidant activity and total phenolic compounds, it was possible to verify that the ethanolic extract of oregano has presented antioxidant potential. Furthermore, considering the results obtained in the analyses of oxidative stability, polar compounds, tocopherols and fatty acids profile, it was possible to observe that the extract has prevented lipid oxidation when added to SO.

The study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which can be considered toxic.

The purpose of this study is to evaluate the effect of the four tautomeric forms of 2-amino-5-mercatpo-1,3,4-thiadizole (AMT) absorbed on copper surface by the polar or non-polar groups. Polar group of AMT is mostly electronegative with larger N and S atoms as central atoms. 5-amino-1,3,4-thiadiazole-2(3H)-thion (AMT-c) has the highest adsorption energy and is easy to react with copper. The interaction between AMT-c and copper conforms to chemisorption, which is to be further verified by the experiment on the weight loss measurement.

Adsorption behavior of AMT as corrosion inhibitor on copper surface in oil field was studied by weight loss measurement, and the corrosion inhibition mechanism was analyzed. Reactive sites and distributions of tautomeric forms of AMT as inhibitor on Cu(100) crystal plane were calculated by density functional theory.

All atoms of AMT are in the same plane, and AMT is an aromatic ring structure by large p-chain adsorbed on the metal surface by a plane configuration. AMT-c has the highest adsorption energy and also the most stable isomerized product. The determinate locations of AMT on the Cu(100) surface are the bridge and the hollow sites using molecular dynamics. Corrosion of copper can be effectively inhibited by AMT, which is a kind of excellent corrosion inhibitor, and this property is attributed to the polar groups and non-polar groups of AMT that play a role as absorption and shielding on copper surface, respectively. Inhibition efficiency is increased with the increase in the concentration of the inhibitor. The maximum efficiency of 92 per cent is obtained for 50 ppm AMT concentration at 373 K, which is attributed to the presence of extensively delocalized electrons of the phenyl rings, planarity and the presence of lone pair of electrons on N and S atoms, which favored a greater adsorption of inhibitors on copper surface.

Corrosion of copper can be effectively inhibited by AMT, which is a kind of excellent corrosion inhibitor, and this property is attributed to the polar groups and non-polar groups of AMT that play a role as absorption and shielding on copper surface, respectively. Adsorption of AMT as corrosion inhibitor on copper surface obeys Langmuir isotherm. The interaction between AMT and copper conforms to chemisorption, which is to be further verified by the experiment on the weight loss measurement.

Existing studies about airline productivity and cost competitiveness are focusing on combination carriers, transporting both passengers and cargo in the same aircraft and with the same inputs. Scientific research about the cost structure and productive performance of all-cargo carriers is very limited. However, the importance of air cargo and express transport in our globalized economy, the high volatility of all-cargo carriers (especially since the 2008 economic crisis), and the success of integrators show the need for more scientific attention to this industry. This chapter aims at benchmarking the productivity and cost competitiveness of US integrated and non-integrated cargo carriers, based on total factor productivity and unit cost competitiveness analyses. The results unveil a positive correlation between productivity on the one hand and the size of the carrier and its average stage length on the other hand, indicating economies of scale. Correcting the results for such factors beyond managerial control and input prices allows us to measure the impact of the crisis and the consequences for the management of the individual carriers.

CELLULOSE is Nature's strong material. It is the chief constituent of cotton flax and wood. Wood can be turned into sugars by treatment with hydrochloric acid Bergius process) and by certain termites; horses and cows break down the cellulose in grass into sugar before digesting it. So it is not surprising that the cellulose polymer is built up of what are practically molecules of a glucose (“Barley Sugar”). Each β glucose unit is twisted about its axis through 180 deg.; the combination of two such units makes up that is called a cellulose unit which has the structure shown in Fig. 2. The cellulose polymer is a long, straight chain made up from these cellobiose units, and each chain probably contains about 70 such units.

The purpose of this paper is to evaluate the antioxidant activity of ginger ethanol extract in soybean oil under thermoxidation.

A total of four treatments were used: soybean oil free of synthetic antioxidants, soybean oil containing 2,500 mg/kg of ginger extract, soybean oil containing 50 mg/kg of TBHQ, soybean oil containing the mixture of natural extract, and TBHQ in the before‐cited concentration. The treatments were discontinuously submitted to plates heated at 180°C, for 20 hours. Samples were removed in the times of 0, 4, 8, 12, 16 and 20 hours of heating and they were analyzed as to their oxidative stability, total polar compounds, peroxide and conjugated diene values.

The results showed the efficiency of the ginger extract in protecting the oil against lipid oxidation. It could be concluded that ginger extract might be indicated as an additive that acts against lipid oxidation and, consequently, increases shelf life of food.

These studies may prove to be beneficial to the exploitation of natural antioxidant sources for the preservation and/or extension of raw and processed food shelf life. Therefore, they could also be applied in the area of pharmaceuticals for the protection of human life.

This study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which might be considered toxic.

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.

The purpose of this study is to formulate a new class of vehicle routing problem with an objective to minimise the total cost of raw material collection and derive a new approach to solve optimization problems. This study can help to select the optimum number of suppliers based on cost.

To model the raw material vehicle routing problem, a mixed integer linear programming (MILP) problem is formulated. An interesting phenomenon added to the proposed problem is that there is no compulsion to visit all suppliers. To guarantee the demand of semiconductor industry, all visited suppliers should reach a given raw material capacity requirement. To solve the proposed model, the authors developed a novel hybrid approach that is a combination of block and edge recombination approaches. To avoid bias, the authors compare the results of the proposed methodology with other known approaches, such as genetic algorithms (GAs) and ant colony optimisation (ACO).

The findings indicate that the proposed model can be useful in industries, where multiple suppliers are used. The proposed hybrid approach provides a better sequence of suppliers compared to other heuristic techniques.

The data used in the proposed model is generated based on previous literature. The problem derives from the assumption that semiconductor industries use a variety of raw materials.

This study provides a new model and approach that can help practitioners and policymakers select suppliers based on their logistics costs.

This study provides two important contributions in the context of the supply chain. First, it provides a new variant of the vehicle routing problem in consideration of raw material collection; and second, it provides a new approach to solving optimisation problems.

A numerical method is presented for analysis of the pneumatic forming process of axisymmetric superplastic thin shells. The governing non‐linear partial differential equations are derived from membrane shell theory, using total Lagrangian description and considering a hardening creep material model. The method of lines used in the computational algorithm, involves two steps: first the Cauchy problem in time is considered, then the boundary problem is solved by finite differences. The effectiveness of the proposed algorithm is illustrated by several examples.