An improved wet method to process oats into fractions enriched with protein, beta-glucan, starch or other carbohydrates

Authors: Liu, Keshun

Submitted to: American Oil Chemists' Society Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/31/2018
Publication Date: 5/6/2018
Citation: Liu, K. 2018. An improved wet method to process oats into fractions enriched with protein, beta-glucan, starch or other carbohydrates. American Oil Chemists' Society Meeting, May 6-9, 2018, Minneapolis, MN. PCP2b.

Interpretive Summary:

Technical Abstract: An improved wet method to process oats into fractions enriched with protein, beta-glucan, starch or other carbohydrates Keshun Liu Abstract for American Oil Chemists Society Annual Meeting, Minneapolis, MN, May 6-9, 2018 Oat ranks sixth in world cereal production, behind wheat, corn, rice, barley and sorghum, and has relatively higher contents of oil and protein with better quality than some other cereal grains. Oat is also among very few grains that contain mixed linkage (1-4, 1-3) beta-D-glucan (BG), which is a soluble dietary fiber that has been shown to lower cholesterol levels. There is a growing interest in incorporating oat or its components (as food ingredients) into the human diet, since oat is naturally healthy, readily available and relatively inexpensive. Various methods to fractionate oats into different value-added fractions have been available, but almost all focused on enrichment with only one or two nutrients while other key nutrients were disregarded (or discarded). This presentation deals with development of a modified wet method to fractionate oats into several value-added ingredients simultaneously, with each enriched for protein, BG, starch, or other carbohydrates (CHO), respectively. Effects of NaOH concentration and solvent to flour ratio on concentration and recovery of the four main nutrients (protein, BG, starch, BG, and other CHO) were also investigated. Seeds of Lamont, a hulless oat variety, were ground into whole grain flour, defatted with hexane, and then extracted with a dilute alkaline solution. Upon centrifugation, fractions, which were enriched for protein, BG, starch or other CHO (fiber), were recovered, respectively. Wet fractions were dried in a forced air oven overnight at 60ºC. The nutrient contents in dried fractions as well as the starting oat material were then measured by official methods, respectively, while the mass of each dried fraction was measured as well. Results show that both NaOH concentration and solvent to flour ratio had significant effects on nutrient concentration and recovery in each type of fractions. The extent of the effects varied with fraction type and nutrients. Overall, the wet method, once optimized, was effective in recovering the major nutrients from oats into their respective fractions.