DIETARY FIBER CONTENT AND COMPOSITION OF VEGETABLES DETERMINED BY 2 METHODS OF ANALYSIS

Forty-one samples representing different forms of 12 types of vegetabl es were analyzed for dietary fiber content using the Association of Of ficial Analytical Chemists method and for fiber content and compositio n using the Uppsala method. Mean fiber content, measured by the former method was 2.1 +/- 0.9 g/100 g and by the latter method, 1.8 +/- 0.8 g/100 g. The mean soluble fiber concentration determined by the Uppsal a method was 15 % of total vegetable fiber. Insoluble fiber contained more neutral sugars than uronic acid; soluble vegetable fiber was a mi xture of uronic acid and polysaccharides containing galactose and arab inose. Cooking either had no effector increased the proportion of tota l fiber extracted as soluble fiber. Some vegetables that are frequentl y treated as similar foods in nutritional studies (e.g., potatoes and cooked greens) contained different amounts of fiber. The results indic ate that for some vegetables the source, preparation method, variety, and analytical method should be considered when daily intakes of total dietary fiber or fiber components are calculated.