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The introduction of gas chromatography by James and Martin in 1952 has been one of the factors contributing to the development of precise detection and monitoring devices across the whole field of chromatography. At the same time the rapid development of solute detection devices has reflected the advances and refinement of chromatographic techniques over the last twenty years.

Advancements in real-time water monitoring technologies permit rapid detection of water quality, and threats from waste loads. Water Framework Directive mandating the establishment of Member States’ water resources monitoring, presence of hazardous contaminants in effluents, and perception of vulnerability of water distribution system to attacks, have spurred technical and economic interests. The paper aims to discuss these issues.

As alternative to traditional analyzers, chemosensors, operate according to physical principles, without sample collection (online), and are capable of supplying parameter values continuously and in real-time. Their low selectivity and stability issues have been overcome by technological developments. This review paper contains a comprehensive survey of existing and expected online monitoring technologies for measurement/detection of pollutants in water.

The state-of-the-art in online water monitoring is presented. Application examples are reported. Monitoring costs will become a lesser part of a water utility budget due to the fact that automation and technological simplification will abate human cost factors, and reduce the complexity of laboratory procedures.

An overview of applicable instrumentation, and forthcoming developments, is given. Technological development in this field is very rapid, and astonishing advances are anticipated in several areas (fingerprinting, optochemical sensors, biosensors, molecular techniques). Online monitoring is becoming an ever-important tool not only for compliance control or plant management purposes, but also as a useful approach to pollution control and reduction, minimizing the environmental impact of discharges.

The analysis and characterisation of resinous binder materials used in paint formulation has been facilitated during the last decade by the availability of such instrumental techniques as infra‐red spectroscopy, gas‐liquid chromatography and, more recently, gel permeation chromatography (G.P.C). The first two techniques mentioned are eminently suitable for the analysis of resins according to their chemical nature. Most of the binder resins used in modern paints are polymers and, therefore, such parameters as molecular weight and degree of polymerisation are important in determining the suitability of a resin for a given application. The G.P.C. technique readily provides the necessary information about these polymer parameters.

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.

This study aims to analyze the soursop and sugar apple seeds as to its composition, to evaluate the antioxidant potential of seeds extract and characterize the oil extracted from them, regarding the fatty acids profile and content of tocopherols.

To obtain the extracts, dried and crushed seeds were extracted with ethanol for 30 minutes, at a ratio of 1:3 (m/m, seed: ethyl alcohol) under continuous stirring at room temperature. Then, the mixture was filtered and the supernatants subjected to rotoevaporator at 40°C aiming to determine, by direct weighing, the yields of dry extracts.

According to the results, the soursop and sugar apple seeds constituted significant sources of lipids, proteins and carbohydrates and can therefore be used in food and feed, and offer relevant antioxidant activity of phenolic compounds. The oil seeds are a good source of unsaturated fatty acids, especially oleic and linoleic acids and they have significant amounts of total tocopherol.

Implications are the identification of bioactive compounds extracted from seeds of tropical and subtropical fruits, and to prevent certain types of diseases.

The information presented might be directly used for developing of functional foods such as fruits.

The article tries to identify new source of compounds extracted from fruits.

With the drastically changed pattern of the retail food trade in recent years in which the retailer's role has become little more than that of a provider of shelves for commodities, processed, prepared, packed and weighed by manufacturers, the defence afforded by the provisions of Section 113, Food and Drugs Act, 1955 has really come into its own. Nowadays it is undoubtedly the most commonly pleaded statutory defence. Because this pattern of trade would seem to offer scope for the use of the warranty defence (Sect. 115) in food prosecutions it is a little strange that this defence is not used more often.

The Protection of Consumers (Trade Descriptions) bill which, owing to the General Election, did not quite make the Statute Book in the last Parliament, is, at the moment of writing, passing through its readings, with every likelihood of becoming law in the near future. It has been criticised for the extent of the control to be exercised over general trading and that in “coddling the customer” it will place unreasonable responsibilities upon retailers. In fact, it is impossible to foresee just how far its provisions may extend, but there will be few who will disagree that new and more searching requirements are long overdue.

The purpose of this paper is to show how a quartz crystal microbalance modified with poly (epichlorohydrin) (PECH) is fabricated and used for detection of acetone vapor using a spin‐coating method.

Measurements are based on the frequency shifts due to the adsorption of acetone vapor on the surface of the modified electrodes. A first‐order linear time‐invariant (LTI) system model is used to simulate the sensor response.

It is found that frequency shifts are linear to the concentrations of analyte, and cycle test examination shows good repeatability. The sensitivity to acetone vapor is better than other volatile compounds. A good match result is obtained with the LTI system model.

The device performance opens a potential way for analyzing acetone vapor.

In a recent reference to changes brought about by the local government reorganisation of 1974, we criticised some of the names given to the new areas. Some of these name changes have made difficulties for those who follow from afar the doings of local authorities, as well as raising the ire of local people. Local names, however, are not the only casualty. The creation of new and larger governmental organisations rarely, if ever, results in economy and as anticipated, it was not long before the new local authorities were being directed to embrace financial stringency and all that it incurs. One such other casualty has been the loss of so many of the annual reports of local authority departments, very few now arriving at BFJ offices. In every case, the reason has been the same—severe restrictions on spending. Not that this was not necessary in many fields, but in respect of annual reports, we are convinced it was false economy. For so many of the reports, it was our pleasure to review them in the pages of BFJ. A prominent Labour politician was once heard to refer to them as “hard and dry reports for hard and dry officials”. It all depends probably on what you are looking for in them. Statistics there must be but most enforcement officers and public analysts, endeavour to keep these to the minimum, the general impression being that these are “dry”. If you are looking for trends, for comparison of the year under review with preceding years and then for comparing the results reported in one part of the country with another, where the population, eating habits, consumer reactions may be different, the tables of statistics are highly important.

DURING the period 1965 to 67, a number of aircraft accidents occurred in which fires contributed significantly to the loss of life.