Dietary fiber content of dry pea, chickpea, and lentil determined using the consensus analytical method, AOAC 2011.25
Date
2017
Authors
Chen, Yiran, author
Thompson, Henry, advisor
Brick, Mark, committee member
Wallner, Stephen, committee member
Journal Title
Journal ISSN
Volume Title
Abstract
The health benefits of dietary fiber and its constituents have been well documented. However, the consumption of dietary fiber is lower than recommended levels worldwide, and the gap between actual consumption and recommended intake represents a widely unrecognized health risk. One approach to address the dietary fiber gap is to return to an ancient tradition that was abandoned in the last 50 years, i.e. the consumption of pulse crops as a dietary staple. To better advocate for an increase in pulse consumption, the determination of the fiber content of these crops using the consensus definition of dietary fiber published in 2009 and the method that conforms to that definition (AOAC 2011.25) is needed. The overall goal of this thesis was to analyze the dietary fiber content of three major pulse crops, dry pea (Pisum sativum L.), lentil (Lens culinaris L.) and chickpea (Cicer arietinum L.) using the consensus definition and method of analysis. OBJECTIVE: The objectives of this project were: 1) to measure dietary fiber content of dry pea, lentil and chickpea using the AOAC 2011.25 method, and 2) to explore relationships among fiber content, pulse genotype (cultivar) and the environment in which these crops were grown. REASERCH DESIGN AND METHOD: The pulse crops analyzed included 11 cultivars of dry pea, 13 cultivars of lentil and 24 cultivars of chickpea, each grown in two locations. Each cultivar was analyzed for insoluble dietary fiber, soluble dietary fiber, oligosaccharides and total dietary fiber content using the AOAC 2011.25 method of analysis. RESULTS: Average total dietary fiber content was 24.6% for dry pea, 20.1% for lentil, and 21.8% for chickpea. The range in total dietary fiber was from 20.1 to 30.6% among dry pea cultivars, from 17.6 to 21.6% among lentil cultivars and from 15.8 to 25.8% among chickpea cultivars. Dietary fiber content in pulse crops varied significantly by cultivar while location of production had a limited effect. CONCLUSION: The pulse crops assessed varied widely in dietary fiber content among cultivars within species indicating that breeding and selection can be used to improve pulse crops for this health beneficial trait, without concern that those improvements would be influenced by factors such as location of production. Overall, the pulse crops investigated had high dietary fiber content relative to other food crops, e.g. wheat (T. aestivum L.), corn (Zea mays L.), or rice (Oryza sativa L.), that are widely promoted in efforts to close the dietary fiber gap. Consumption of 2 to 3 servings per day of any of these pulse crops would eliminate the dietary fiber gap. The data presented also indicated that consumers can be guided to choose pulse crop cultivars that are enriched in fiber content as a way to further improve dietary fiber status without increasing caloric intake. Re-establishing pulse crops as a staple in Western diets illustrates the potential value of considering the pursuit of ancient solutions to solve 21st century challenges at the interface of agriculture and human health.