Available at: https://digitalcommons.calpoly.edu/theses/3156
Date of Award
9-2025
Degree Name
MS in Nutrition
Department/Program
Food Science and Nutrition
College
College of Agriculture, Food, and Environmental Sciences
Advisor
Scott Reaves
Advisor Department
Food Science and Nutrition
Advisor College
College of Agriculture, Food, and Environmental Sciences
Abstract
Plant-based protein is growing in popularity and demand due to ongoing trends in health-consciousness and sustainability. Plant-based proteins are not as effective as animal-based proteins in terms of digestibility and bioavailability. Methods including complementation and fortification are used to increase plant-based protein quality. The purpose of this study was to assess protein quality of almond (AP), amino-acid-fortified-almond (AP+), and whey (WP) protein powder supplements by investigating their effects on the nitrogen balance and postprandial amino acid concentrations of healthy, college-aged females. This study was single-blind and utilized a staggered, rolling start design. Nitrogen balance significantly increased with all three supplements, with no statistical difference between each group’s effect. Amino acid profiles were measured at baseline and 60-minutes postprandial. All supplements elicited an increase in total amino acid (TAA) concentrations from baseline to 60-minutes. WP caused a significantly greater change in TAA than AP, and AP+ was not significantly different from either group. For both essential amino acid (EAA) and leucine concentrations, WP and AP+ caused similar increases from baseline to 60-minutes, both significantly greater than AP’s effect. This study highlights the effectiveness of fortifying a plant-based protein with amino acids to increase overall protein quality. Future studies will include investigation of the effect of AP and AP+ on muscle protein synthesis.