Oat Milk By-Product: A Review of Nutrition, Processing and Applications of Oat Pulp

Oat milk production is increasing due to consumer demand for nutritious dairy alternatives. Oat pulp is an insoluble residue and the main by-product of oat milk production. Approximately 0.2–0.45 kg of oat pulp is generated from every 1 kg of oat milk, and an estimated 228 kilotons is produced annually on a global scale, which is projected to increase to 500 kilotons by 2030. Oat pulp is rich in protein, dietary fibre, β-glucan, lipids, and bioactive compounds, but rapidly degrades due to microbial activity, and this byproduct is currently discarded to landfills with an associated negative impact on the environment. To promote the valorisation of oat pulp, it is important to understand the nutritional profile, oat milk processing, and its current applications. This review outlines and discusses oat milk production, nutrition, functionality, and food applications of oat pulp, and then proposes research trends for the valorisation of oat pulp, including fractionation into protein, dietary fibre, starch, and bioactive-rich fractions with potential use for various purposes. Cost-effective utilization of oat pulp and similar by-products is vital in tackling both environmental issues and the escalating need for sustainable food production.