Edna Emy Kumagai

Bio: Edna Emy Kumagai is an academic researcher from Instituto Adolfo Lutz. The author has contributed to research in topics: Fatty acid & Gas chromatography. The author has an hindex of 8, co-authored 14 publications receiving 242 citations.

Determinação da diferença entre o valor real e o teórico do triglicerídeo ECN 42 para a detecção de adulteração em azeites de oliva comercializados no Brasil

Abstract: CALCULATION OF THE DIFFERENCE BETWEEN THE ACTUAL AND THEORETICAL ECN 42 TRIACYLGLYCERIDE CONTENT TO DETECT ADULTERATION IN OLIVE OIL SAMPLES COMMERCIALIZED IN BRAZIL. The difference between the actual ECN 42 triacylglyceride content in vegetable oils, obtained by HPLC analysis, and the theoretical value calculated from the fatty acid composition was applied to detect the addition of seed oils with high contents of linoleic acid to olive oils commercialized in Brazil. The results indicate that samples analyzed were probably adulterated with low commercial value seed oils, rich in linoleic acid, like soybean, sunflower or corn.

Sistematic study of benzo[a]pyrene in coffee samples

Abstract: A method for extracting and quantifying benzo[a]pyrene (B[a]P) was evaluated and improved for samples of green and roasted ground Arabica (Coffea arabica) and Conillon (Coffea canephora) Brazilian coffees. The influence of the roasting process in B[a]P formation was considered too. These samples were extracted with acetone, followed by saponification and cyclohexane extraction. The extracts were cleaned by chromatography on a silica-gel. The quantification was done by HPLC with reversed-phase and fluorescence detection under isocratic conditions. The detection and quantification limits were 0.03 µg kg-1 and 0.10 µg kg-1, respectively. The recovery ranged from 76 to 116% for concentrations between 1.00 and 3.00 µg kg-1. The values obtained for B[a]P concentrations were from 0.47 to 12.5 µg kg-1 for samples of ground roasted coffee. B[a]P was absent in the green coffee samples. The control of the roasting parameters is fundamental for obtaining a good quality product.

Comparison of gas chromatographic and gravimetric methods for quantization of total fat and fatty acids in foodstuffs

Abstract: Different methods to determine total fat (TF) and fatty acids (FA), including trans fatty acids (TFA), in diverse foodstuffs were evaluated, incorporating gravimetric methods and gas chromatography with flame ionization detector (GC/FID), in accordance with a modified AOAC 996.06 method. Concentrations of TF and FA obtained through these different procedures diverged (p< 0.05) and TFA concentrations varied beyond 20 % of the reference values. The modified AOAC 996.06 method satisfied both accuracy and precision, was fast and employed small amounts of low toxicity solvents. Therefore, the results showed that this methodology is viable to be adopted in Brazil for nutritional labeling purposes.

Ácidos graxos saturados versus ácidos graxos trans em biscoitos.

Abstract: The ingestion of saturated fatty acids can eventually bring health risks. Scientific evidence shows that the intake of trans isomer fatty acids creates a similar effect as the intake of saturated fatty acids. Brazilian laws demand only to declare on the label the content of saturated fatty acids. Several products are made by using hydrogenated vegetable fat, which is rich in trans isomers fatty acids, for example cookies, which are generally eaten by children and adolescents. The objective of this work was to compare the contents of saturated fatty acids and trans isomer fatty acids in different cookie samples and supply Brazilian authorities with information to implement laws. Twenty six samples were analyzed in six different brands. The four types of cookies tested were: wafers, salty cookies, cream filled and several sweet ones. The composition of fatty acids from the fat extracted of the cookies (Soxhlet) was determinated by gas chromatography. The contents of saturated and trans isomer fatty acids were similar in most samples, which showed a considerable percentage of the total lipids content. The results obtained will bring subsidies to reformulate the Brazilian laws, which will then demand that the content of trans isomer fatty acids, should be included on the labels of the cookie packets, and of other products with high content of trans isomer fatty acids, considering health implications.

A Review on Frying: Procedure, Fat, Deterioration Progress and Health Hazards

Abstract: For decades, frying has been a popular technique for the preparation of foods, both on domestic and industrial scales. The effects of edible oil type and frying operation conditions on the shelf-life of fried products, the deterioration progress and the health hazards of fried foods have been studied by various researchers. To achieve a clear conception of the present situation, a collection of the results obtained from previous studies about product deterioration and safety issues due to the frying process, along with related tables, are of prime importance. According to the studies, it can be concluded that a vacuum, oil replenishment, frying temperature, and time of process are the most important parameters affecting the quality of oils and fried products; hence, by controlling them, it is possible to prevent the formation of toxic compounds and loss of nutritional components to a considerable extent during frying operation. Furthermore, according to recent studies indicating significant formation of toxic compounds before the chemical indices of the oil reach the disposal point, more studies are needed to determine whether they are formed at levels that compromise safety and affect consumers’ sensory perception before the established discard points.