INTERNATIONAL SURVEY ON DIETARY FIBER - DEFINITION, ANALYSIS, AND REFERENCE MATERIALS

An international survey was conducted to get the views of 147 professi onals in the field on the definition of dietary fiber. The survey also solicited opinions on analytical methods for nutrition labeling, qual ity control, and nutrition research. The survey finds that dietary fib er is generally defined as polysaccharides and lignin that are not hyd rolyzed by human alimentary enzymes. Support is strong for expansion o f the definition to include oligosaccharides that are resistant to hyd rolysis by human alimentary enzymes. Among techniques for nutrition la beling and quality control, enzymatic-gravimetric methods get the high est support. For nutrition research, more detailed methods such as gas -liquid chromatography and liquid chromatography were considered more appropriate. Respondents support labeling of total, soluble, and insol uble dietary fiber or total dietary fiber alone as sufficient for nutr ition labeling of food packages. However, for nutrition research, deta iled analytical methods, improvements in accuracy (i.e., closer simula tion of in vitro techniques to conditions of human gastrointestinal tr act), and improvements in precision and simplicity are suggested. Less than 20% of the participants use reference materials for dietary fibe r analysis.