Search results

Cooking can adversely affect chemical characteristics of edible oils. The purpose of this paper is to determine biochemical changes due to cooking in commonly used Indian fats and oils through an experimental study.

Changes in chemical properties of various edible oils [Indian ghee (clarified butter), hydrogenated oil, coconut oil, mustard‐rapeseed oil, groundnut oil, soyabean oil, cottonseed oil and sunflower oil] were studied. Oils were subjected to various cooking methods (shallow frying, sautéing, single deep frying and multiple deep fryings) using an inert substance. Peroxide content was estimated as index of fatty‐acid oxidation, free fatty acids, iodine value for determination of fatty‐acid unsaturation and trans‐fatty acids at baseline and after cooking using colorimetric and gas‐liquid chromatography methods. Three samples were analyzed for each process (n = 144). Significance of change was determined using t‐test.

There was a significant increase in peroxide content (mEq/L) of Indian ghee from 1.83±0.03 at baseline to 4.5–6.6 by different cooking methods, hydrogenated oil (0.45±0.07 to 1.7–8.5), coconut oil (1.01±0.01 to 3.2–9.2), mustard‐rapeseed oil (0.90±0.01 to 2.1–5.3), groundnut oil (0.96±0.01 to 1.9–3.7), soyabean oil (0.86±0.02 to 1.9–3.4), cottonseed oil (0.71±0.01 to 2.9–6.4) and sunflower oil (1.09±0.01 to 2.3–10.2) (p<0.05). Free fatty acid content (g/100 g) was in undetectable amounts in all the fats at baseline and increased in Indian ghee (0.16–0.22), hydrogenated oil (0.09–0.23), coconut oil (0.09–1.39), mustard‐rapeseed oil (0.07–0.19), groundnut oil (0.09–0.18), soyabean oil (0.06–0.12), cottonseed oil (0.09–0.22) and sunflower oil (0.08–0.13). Trans‐fatty acids increased from 0.1% at baseline to 14.5% after sautéing and shallow frying and 15.8–16.8% after deep frying in hydrogenated oils (p<0.01). The iodine value decreased, indicating a decrease in unsaturated fats, insignificantly. The largest amount of oxidation was observed by shallow frying and free‐fatty‐acid formation by multiple deep frying. Hydrogenated, coconut and sunflower oils were the most susceptible to oxidation and soyabean oil the most resistant. Single deep frying caused the least changes in chemical composition of various fats and oils. Indian cooking practices significantly increase the peroxides, free fatty acids and trans‐fatty acids in edible oils and fats. Single deep frying appears to be the least harmful method and soyabean oil the least susceptible to degradation.

The paper offers an experimental study to determine biochemical changes due to cooking in commonly used Indian fats and oils.

The purpose of this paper is to speak about the production of biodiesel from waste cooking oil which serves as an alternate fuel in the absence of conventional fuels such as diesel and petrol. Though much research work was carried out using non-edible crops such as Jatropha and Pongamia, cooking oil utilized in bulk quantity is discarded as a waste. This is reused again as it contains more of esters that when combined with an alcohol in presence of an enzyme as a catalyst yields triglycerides (biodiesel).

The lipase producing strain Rhizopus oryzae and pure enzyme lipase is immobilized and treated with waste cooking oil for the production of FAME. Reaction parameters such as temperature, time, oil to acyl acceptor ratio and enzyme concentration were considered for purified lipase and in the case of Rhizopus oryzae, pH, olive oil concentration and rpm were considered for optimization studies. The response generated through each run were evaluated and analyzed through the central composited design of response surface methodology and thus the optimized reaction conditions were determined.

A high conversion (94.01 percent) was obtained for methanol when compared to methyl acetate (91.11 percent) and ethyl acetate (90.06 percent) through lipase catalyzed reaction at oil to solvent ratio of 1:3, enzyme concentration of 10 percent at 30°C after 24 h. Similarly, for methanol a high conversion (83.76 percent) was obtained at an optimum pH of 5.5, olive oil concentration 25 g/L and 150 rpm using Rhizopus oryzae when compared to methyl acetate (81.09 percent) and ethyl acetate (80.49 percent).

This research work implies that the acyl acceptors methyl acetate and ethyl acetate which are novel solvents for biodiesel production can also be used to obtain high yields as compared with methanol under optimized conditions.

Describes a study to measure the quality of service provided by food‐poisoning surveillance agencies in England and Wales in terms of the requirements of a representative consumer ‐ the egg producing industry ‐ adopting “egg associated” outbreak investigation reports as the reference output. Defines and makes use of four primary performance indicators: accessibility of information; completeness of evidence supplied in food‐poisoning outbreak investigation reports as to the sources of infection in “egg‐associated” outbreaks; timeliness of information published; and utility of information and advice aimed at preventing or controlling food poisoning. Finds that quality expectations in each parameter measured are not met. Examines reasons why surveillance agencies have not delivered the quality demanded. Makes use of detailed case studies to illustrate inadequacies of current practice. Attributes failure to deliver “accessibility” to a lack of recognition on the status or nature of “consumers”, combined with a self‐maintenance motivation of the part of the surveillance agencies. Finds that failures to deliver “completeness” and “utility” may result from the same defects which give rise to the lack of “accessibility” in that, failing to recognize the consumers of a public service for what they are, the agencies feel no need to provide them with the data they require. The research indicates that self‐maintenance by scientific epidemiologists may introduce biases which when combined with a politically inspired need to transfer responsibility for food‐poisoning outbreaks, skew the conduct of investigations and their conclusions. Contends that this is compounded by serious and multiple inadequacies in the conduct of investigations, arising at least in part from the lack of training and relative inexperience of investigators, the whole conditioned by interdisciplinary rivalry between the professional groups staffing the different agencies. Finds that in addition failures to exploit or develop epidemiological technologies has affected the ability of investigators to resolve the uncertainties identified. Makes recommendations directed at improving the performance of the surveillance agencies which, if adopted will substantially enhance food poisoning control efforts.

The purpose of this paper is to identify technological challenges and innovative solutions in each of the food production philosophies in the food service sector, namely: industrial cuisine, fast food and fresh food.

The paper reviews industry reports on cooking equipment and preparation techniques. Conceptual links are made with possible future developments as well as operational/strategic advantages they represent.

Innovation in food preparation commands multi‐disciplinary approaches stemming from engineering and food science. Industrial cuisine would benefit from automation, units with intensive heating, robust food product design and shelf‐life extension; fast food from reduced oil absorption by food, better cooking oils, automation and short frying time; and fresh food from rapid cooking, visually appealing serving units and analytical instrumentation for testing raw produce. Future innovations may originate in the field of robotics, food engineering and laboratory equipment design including miniaturisation and portability of units. Sophistication in product development can be achieved through application of the principles of molecular gastronomy in combination with computer modelling.

Managers can conceptualise their operations in terms of the philosophies presented in the paper. Technological innovation is critical to sustain competitiveness (cost leadership and differentiation). The list of underpinning disciplines in food production can be used by educators wishing to enhance their programs with fundamentals supporting innovation.

Food preparation philosophies are presented in the light of impacts on food sensory and microbiological quality, nutritional value and operational efficiencies. The possibilities for future innovation stemming from developments in other technologically advanced fields are identified.

At the commencement of this decade, leaving behind the “striking seventies”, we christened it the “anxious eighties”, for there was a profound disquiet and uncertainty among most of the population, a fear that things were going to get worse, but they could have hardly expected the catastrophic events of the year 1981. The criteria of quality of life are its richness, grace, elegance; by the promise it contains; inspiration and purpose, hope, determination (to survive, to make certain that the evildoer is not permitted to succeed), love of one's country — pro patria, of other days.

This study aims to update the information on the current status of micronutrient fortification for iron, zinc, folic acid and vitamin A in mandatory fortified food vehicles such as cooking oil, wheat and maize flours in Tanzania.

A cross-sectional study was conducted in five regions to analyze the adequacy of micronutrient fortification in mandatory fortified food vehicles. Samples of fortified edible oil (n = 19), wheat flour (n = 12) and maize flour (n = 5) were sampled conveniently from local markets and supermarkets. Samples were analyzed for vitamins (vitamin A and folic acid) and mineral (iron and zinc) content using high-performance liquid chromatography and microwave plasma-atomic emission spectrometer, respectively. Compliance acceptable ranges between the minimum and maximum levels for each nutrient were used as a basis for compliance.

The results showed that 83.3% and 80% of wheat and maize flour samples, respectively, complied with iron fortification standards (p = 0.05). Only 25% of wheat flour samples and 40% of maize flour samples were within the acceptable ranges for zinc fortification (p = 0.05). Nearly 17% and 20% of wheat and maize flour samples, respectively, were within the acceptable ranges for folic acid fortification (p = 0.05). Moreover, about 10.5% of the analyzed cooking oils were adequately fortified with vitamin A (p = 0.05). Except for iron in wheat and maize flours, the levels of other micronutrients in mandatorily fortified foods were out of acceptable ranges.

Mandatory fortification is still far from the established standards, and this calls for a review of the current fortification strategies regarding standards, training, monitoring and enforcement in Tanzania.

The purpose of this paper was to investigate the lubricity of palm biodiesel (PB)–diesel fuel with plastic pyrolysis oil (PPO) and waste cooking biodiesel (WCB).

Three quaternary fuels were prepared by mechanical stirring. B10 (10% PB in diesel) fuel was blended with 5%, 10% and 15% of both PPO and WCB. The results were compared to B30 (30% PB in diesel) and B10. The lubricity of fuel samples was determined using high-frequency reciprocating rig in accordance with ASTM D6079. The tribological behavior of all fuels was assessed by using scanning electron microscopy on worn steel plates to determine wear scar diameter (WSD) and surface morphology. The reported WSD is the average of the major and minor axis of the wear scar.

The addition of PPO and WCB to B10 had improved its lubricity while lowering wear and friction coefficients. Among the quaternary fuels, B40 showed the greatest reduction in coefficient of friction and WSD, with 7.63% and 44.5%, respectively, when compared to B10. When compared to B30a, the quaternary fuel mixes (B40, B30b and B20) exhibited significant reduction in WSD by 49.66%, 42.84% and 40.24%, respectively. Among the quaternary fuels, B40 exhibited the best overall lubricating performance, which was supported by surface morphology analysis. The evaluation of B40 indicated a reduced adhesive wear and tribo-oxidation, as well as a smoother metal surface, as compared to B20 and B30b.

Incorporation of PPO and WCB in PB–diesel blend as a quaternary fuel blend in diesel engines has not been reported. Only a few researchers looked into the impact of PPO and WCB on the lubricity of the fuel.

This paper aims to review the chemical composition and industrial benefits of oil extracted from dikanut kernels.

Several literatures on chemical composition of dikanut kernels, methods of oil extraction from dikanut kernels and chemical composition of oil extracted from dikanut kernels were critically reviewed.

The review showed that proximate composition of dikanut kernels ranged from 2.10 to 11.90 per cent, 7.70 to 9.24 per cent, 51.32 to 70.80 per cent, 0.86 to 10.23 per cent, 2.26 to 6.80 per cent and 10.72 to 26.02 per cent for moisture, crude protein, crude fat, crude fibre, ash and carbohydrate contents, respectively. The methods of oil extraction from dikanut kernels include soxhlet extraction method, novel extraction method, enzymatic extraction method and pressing method. The quality attributes of dikanut kernel oil ranged from 1.59 to 4.70 g/100g, 0.50 to 2.67 meq/Kg, 4.30 to 13.40 g/100g, 187.90 to 256.50 mg KOH/g and 3.18 to 12.94 mg KOH/g for free fatty acid, peroxide value, iodine value, saponification value and acid value, respectively. Also, the percentage compositions of oleic, myristic, stearic, linolenic, palmitic, lauric, saturated fatty acids, monosaturated fatty acids and polyunsaturated fatty acids ranging from 0.00 to 6.90, 20.50 to 61.68, 0.80 to 11.40, 0.27 to 6.40, 5.06 to 10.30, 27.63 to 40.70, 97.45 to 98.73, 1.82 to 2.12 and 0.27 to 0.49 respectively. The results showed that dikanut kernels has appreciable amount of protein, carbohydrate and high level of fat content while oil extracted from dikanut kernels have high saponification value, high myristic acid and high lauric acid.

There are scanty information/published works on industrial products made from oil extracted from dikanut kernels.

The review helps in identifying different methods of extraction of oil from dikanut kernels apart from popular soxhlet extraction method (uses of organic solvent). Also, it helps to identify the domestic and industrial benefits of oil extracted from dikanut kernels.

The review showed that oil extracted from dikanut kernels could be useful as food additive, flavour ingredient, coating fresh citrus fruits and in the manufacture of margarine, oil creams, cooking oil, defoaming agent, cosmetics and pharmaceutical products.

In Somerset samples of all kinds submitted and examined amounted to 1,880. Out of these, 1,666 were taken under the Food and Drugs Act, 1898, and the Statutory Rules and Orders issued by the Ministries of Health and Food and the Public Health Acts. It may be observed, though the fact is but too well known to. all those who are officially concerned with the administration of the Acts referred to above, that the number of Rules and Regulations is now very large. This number, by the very nature of the conditions that gave rise to them, will certainly increase. It follows that though the number of samples submitted may not increase, the work in connection therewith will certainly do so. Thus out of forty‐one samples described as either adulterated or incorrect, about half were incorrectly labelled. If this were only a matter of name and address the error or omission could be easily put right, but claims may be made by the vendors that cannot be substantiated. This is left to the Public Analyst to decide. Thus: “Should not bear a reference to scrofula”; or “‘Double strength’ has no meaning”; or “Should not be described as a ‘Cocktail’.” The Public Analyst has the double duty of correcting all sorts of verbal inaccuracies or exaggerations, and carrying out an analysis, often of a most complex description, and then interpreting the results of that analysis. Out of 689 milks examined, 72, or 10·4 per cent, were adulterated, against only 4 per cent in 1946. “This apparent increase in adulteration is probably due to the fact that a large number of samples were taken as a result of complaints received from milk factories.” Cow fat content was in some cases directly traceable to the large proportion of Friesian cows in the herd. The farmers were recommended to introduce into their herds cows of a breed giving milk with a higher proportion of fat. The old fault of bad mixing was responsible for some other prosecutions. Thus 8·67 per cent of fat at the top of the churn and 2·70 at the bottom at the time of delivery. The Report observes that a substance called Ground Almond Substitute should correspond to some extent with ground almonds. This remark was suggested as a result of examining a sample of the alleged substitute. It had a slight odour and flavour of almonds, but no further resemblance to almonds. The 4·2 per cent of fixed oil was mainly derived from the wheat—85 per cent—and the soya flour—15 per cent—of which it was composed. As flour costs 3d. a lb., and soya flour 10½d. a lb., it is pointed out that the cost of this mixture would be 4½d. a lb. It was sold for 2s. a lb. We are glad to note that the magistrate's view of the swindle was a £5 fine. As it might be used raw for cake icing or marzipan, the result of ingesting this rubbish would probably bring about digestive troubles in young children.

This study aims to improve the performance and to regulate the harmful emission from the diesel engine. For this purpose, palm oil biodiesel (POBD), waste cooking biodiesel (WCBD) and animal fat biodiesel (AFBD) are used for examination.

The transesterification process was followed to convert the three raw oils into biodiesels and the experiments are conducted at various loads with fixed 25 rps. Diesel as a reference fuel and three neat biodiesels are tested for emissions and performance. By training the experimental results in an artificial neural network (ANN), the best biodiesel was predicted.

The biodiesels are tested for significant fuel properties with the American Society for testing and materials standards and observed that kinematic viscosity, density and cetane number are recorded higher than diesel fuel. The fatty acid composition (FAC) from chromatography reveals the presence of unsaturated FAC is more in POBD (70.89%) followed by WCBD (57.67%) and AFBD (43.13%). The combustion pressures measured at every degree of crank angle reveal that WCBD and AFBD exhibited on far with diesel fuel. Compared to diesel fuel WCBD and AFBD achieved maximum brake thermal efficiency of 31.99% and 30.93% at 75% load. However, there is a penalty in fuel consumption and NOx emissions from biodiesels. On the other hand, low carbon monoxide, unburnt hydrocarbon emissions and exhaust smoke are reported for biodiesels. Finally, WCBD was chosen as the best choice based on ANN modeling prediction results.

There is no evident literature on these three neat biodiesel applications with the mapping of ANN modeling.