Tuning the aroma and flavor of plant-based proteins

Abstract: The rise in the demand for plant-based foods and beverages has motivated researchers to explore novel avenues of incorporating plant-based proteins into alternative formulations. Our research focus has been on reducing the greeny and beany off-flavors occurring in plant-based beverages (dairy alternatives). We report the application of direct steam injection, microwave-vacuum dehydration, and lactic acid fermentation methodologies as pre-treatment methods for the plant-protein isolates used in the preparation of high protein plant-based beverages. We shall highlight the methodology used to estimate the aroma intensity for process optimization purposes using a headspace GC-MS method, as well report on its' application to optimize the above food processes to maximize their potential of mitigating the plant-associated off-flavors in such formulations. A sensory analysis was also conducted to confirm the findings and report the effect of the three discussed interventions on the acceptability of the constituted plant-based beverage. Results reveal that while direct steam injection was able to remove the plant-based off-flavors, this approach introduced a cooked or burnt flavor. Microwave-vacuum dehydration was successfully able to reduce the aroma intensity, but also resulted in browning reactions due to the speedup of these reactions at 0.4-0.7 water activity, yet a high-water activity microwave-vacuum dehydration was found to the most optimal approach. Lactic acid fermentation resulted in increase in the alcohols in the aroma profile, resulting in fermented flavors, which masked the greeny and beany off-flavors without introduction of any burnt or browning-reaction related aromas. Results from our studies could be used to inform the creation of alternative beverages with high protein content.