Keywords
nutritional labeling
GC analysis
fatty acids methyl esters
How to Cite
Abstract
The present paper describes the data observed in comparing procedures for determining saturated fatty acids for nutritional labeling by GC/FID. Two procedures to prepare the fatty acids methyl esters [a cold base-catalyzed with KOH 0,2 molL-1 methanolic, and a base and acid - combined procedure (Hartman and Lago)] were compared. Also, two methods were evaluated for calculating the fatty acid concentration, expressed in grams per 100 grams of food (by means of internal standard, and by normalization of area multiplied by theoretical conversion factors). Six samples were analyzed: egg, two types of cookies, soya extract, cappuccino powder, and coffee powder. Variance analysis and Tukey test (p< 0,05%) were applied. No significant difference was observed between the methylation procedures. On the other hand, significant difference was observed in calculating both method for determining the saturated fatty acids in cappuccino and coffee samples. The results point out that it is necessary to use internal standard to quantify the fatty acids in foodstuffs, and further studies should be done to evaluate the use of theoretical factors to calculate fatty acids composition in foodstuffs containing several ingredients.References
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