What is Oat Fiber?
Oat fiber is an insoluble fiber composed of lignin, cellulose, and hemicellulose. The fiber is made from grinding oat hulls that have been separated from the oat groats (kernels).1 It is added to baked goods for its adhesive, absorbent, and textural properties.
Oats are mainly grown in the northern Midwest states in the United States. Oat hulls are a waste product created during the milling process.
Oat fiber has no nutritional value. It is 96% carbohydrate in the form of insoluble dietary fiber.2 The hulls contain 30–35% fiber, 30–35% pentosans, and 10–15% lignans, protein, and ash – the third of these is high in silicic acid.3
Research done by Kamaljit et al. replaced wheat flour in bread formulations with oat fiber. The study concluded that oat fiber could be used at 3% to 5% weight of wheat flour in bread formulas.4
The added oat fiber increased fiber content and maintained standard shelf life when compared with a 5-day control. Organoleptically, the bread with oat fiber at 5% or less earned higher ratings for acceptability from panelists. Scores were given for appearance, crust color, aroma and taste. The acceptability score for oat fiber bread was 7.79 in comparison with the control score of 7.86.4 The study looked at qualities such as baking absorption, loaf volume, loaf height, and specific volume, and achieved best results at a 3% usage rate.4
The process for commercial production of oat hulls into a dietary fiber product was patented in 1991.
The process is as follows:5
- Ground oat hulls are subjected to an alkaline digestion at elevated temperatures and pressures.
- The digested oat hulls are then filtered, neutralized, and bleached to form the desired end product.
Oat fiber added to baked goods can increase dietary fiber. Current applications include low carbohydrate formulas and gluten-free products.
Recommended usage level range is 0.5–5% flour weight.4
The FDA has additional guidelines for the use of oat fiber in baked goods:6
- Use as an ingredient in bread/pizza crust, cookies/crackers/bars, cereal (hot and cold), baby food cereal, and snacks (fried and baked) at levels ranging from 5% to 14% by weight.
- Use as an ingredient in breaders and batters applied to meat and poultry at levels ranging from 2% by weight of the total food system (breaded or coated meats) to 5% by weight of the dry coating system (breader and batter).
Oat fiber is approved by the FDA under GRN No. 261 for use as a food ingredient.6
- U.S. Food and Drug Administration. “Science Review of Isolated and Synthetic Non-Digestible Carbohydrates.” Nov. 2016, www.fda.gov/downloads/Food/IngredientsPackagingLabeling/LabelingNutrition/UCM529049.pdf.
- “Oat Fiber Nutrition Facts & Calories.” SELF Nutrition Data: Know What You Eat, http://nutritiondata.self.com/facts/custom/1443968/1.
- Decker, E., et al. “Processing of Oats and the Impact of Processing.” British Journal of Nutrition, vol. 112, 2014, pp. S58–S64.
- Kamaljit, K., et al. “Analysis of Ingredients, Functionality, Formulation Optimization and Shelf Life Evaluation of High Fiber Bread.” American Journal of Food Technology, vol. 6, 2011, pp. 306–313. DOI: 10.3923/ajft.2011.306.313.
- Ramaswamy, S. Fiber and Method of Making. US patent 5023103 A. 11 June 1991.
- U.S. Food and Drug Administration. “GRAS Notices 261 Oat Hull Fiber.” 3 Feb. 2009. www.accessdata.fda.gov/scripts/fdcc/?set=GRASNotices&id=261&sort=GRN_No&order=DESC&startrow=1&type=basic&search=oat hull fiber.