The Effect of Germination on the Physicochemical, Functional, and Nutritional Properties of Yellow Pea, Red Lentil and Green Lentil Flours
Date
2023-04-20
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0009-0008-9311-2402
Type
Thesis
Degree Level
Masters
Abstract
Abstract
Pulses have been a staple protein in many vegetarian and low-cost diets in the Middle East and Asia. In recent years, their popularity has also risen in Western diets, as more consumers are turning to plant-based proteins instead of animal derived products. Germinating pulses have been shown to improve their nutritional values in multiple ways; by increasing protein contents, improving the amino acid scores, and improving digestibility of the raw seed. In this study, yellow peas, green lentils, and red lentils were germinated for up to three days. The germinated seeds were milled into flour, and several properties of the flours were analysed, including their compositional changes, and physicochemical properties, such as water and oil holding capacity, foaming, and emulsifying properties, and protein solubility. The flour was also analysed for α-amylase activity, starch digestibility, and pasting properties. Overall, germination of pulses had significant impacts on the composition and functionality of the pulse flours. The protein content increased in flours from germinated seeds, whereas the starch content decreased. The resulting flours showed improved water holding capacity, emulsifying activity and capacity, and reduced protein solubility. The foaming capacity of each flour varied with length of germination. The lentil flours were much lower in viscosity in flours from the germinated seeds, while in yellow pea, the effects of germination did not have as large of an impact. The pasting temperature of each pulse flour was also lower than untreated flour when derived from the germinated seed. Germination had varied effects on the nutritional properties of pulses. The in-vitro protein digestibility corrected amino acid score (IV-PDCAAS) of yellow peas was highest in the soaked sample. In red and green lentils, the in-vitro protein digestibility (IVPD) decreased after germination, resulting in a decrease in the IV-PDCAAS. The starch digestibility of all three pulses was improved by germination. In all samples, the percentage of rapid digesting starch (RDS) and slow digesting starch (SD) increased after germination, while the percentage of resistant starch was highest in soaked seed samples, then decreased with germination time.
Description
Keywords
Lentils, peas, pulses, pulse flour, germination
Citation
Degree
Master of Science (M.Sc.)
Department
Food and Bioproduct Sciences
Program
Food Science