ANALYSIS OF VARIATION IN CONCENTRATION OF ESSENTIAL AND NON ESSENTIAL ELEMENTS IN CANNED AND FRESH FOOD

Abstract

ABSTRACT Essential (copper, nickel and zinc) and nonessential (cadmium, lead and tin) elements were determined in canned and fresh food samples employing the technique of Flame Atomic Absorption Spectrophotometry. Food samples were purchased from the shelves of local markets of Rawalpindi, Islamabad and Wah Cantt, Pakistan. Canned food samples were analyzed to study the effect of temperature, time and pH on concentration of elements. To determine the magnitude of variation in concentration of elements in canned food, elemental analysis was performed on samples (food and medium) upon initial opening, and samples upon 4 weeks after opening. The physical observation of the canned food samples was also made to determine the internal coating (lacquer), headspace level and pH of the medium upon opening the can. The result showed that concentration of elements in canned food samples was greater than fresh food, and it increases with increasing time and temperature but decreases with increasing pH. A low concentration of elements was found related to fully lacquered cans, high pH of medium, low nitrate concentration and small headspace. The concentration of elements in each sample was compared statistically. PRACTICAL APPLICATIONS Food quality surveillance is a very important tool to develop a perspective of human health risks. The study is significant in evaluating the concentration of different elements in the food and the effect of their toxicities. This research has a very significant application at the end user level as to give information about the benefits of the fresh food over the canned food. The food industry can benefit from the study as it provides the details over the canned food about the usage and storage. It also provides background knowledge about the deadlines of storage with respect to different essential metal levels. Taking it as a precautionary measure, many of the digestive diseases and abdominal problems can be avoided in masses. Industry can benefit by it to reduce these elements to the minimum possible levels, and can search techniques to decrease the concentration of these elements. It will assist the industries to develop procedures to conserve the food in good optimal manner for best possible, healthier levels. It will stress the desirability of the establishment of tolerances for metal in all foods as a public health measure. It will create awareness in Pakistan of food science and technology. It will also aid the health and food inspectors in improving food quality and developing strategies to reduce the level of metal contamination in the food and to make it according to the WHO guidelines for food quality. This work has opened the doors to investigate the food quality in details with special reference to public health.