Nonenzymatic-Gravimetric Determination of Total Dietary Fiber in Fruits and Vegetables

Open Access
Publisher Website
Google Scholar
Abstract
Most gravimetric methods for total dietary fiber (TDF) determination require the complete removal of starch and the partial removal of protein with various combination of enzymes In buffers at different pH values and at temperatures much above ambient condition. A hydrolysis step Is crucial In dietary fiber analysis of samples, such as cereals and legumes, which contain appreciable amounts of starch. However, many vegetables and most fruits contain very little or no starch, and they are often eaten uncooked. It would be unnecessary to use high temperatures and enzymes on these types of samples. Initially, we found that hexane and dilute alcohol extractions of a few selected fruits and vegetables gave residue weights comparable to those after enzymatic treatments. We were able to show later that simply suspending the samples in delonized water for 90 mln at 37°C and then adding 95% ethanol also yields TDF values similar to those obtained from other published methods. Comparison data obtained by using variations of the AOAC/TDF method are presented for 10 fruits and vegetables.

This publication has 0 references indexed in Scilit: