Polypeptides produced from lentils as novel fat replacers and use in improving non-fat yogurt texture
Research Poster Health & Life Sciences 2025 Graduate ExhibitionPresentation by Ishita Ghosh
Exhibition Number 18
Abstract
There is a growing consumer demand for healthier low-fat or non-fat food products. However, fat plays a crucial role in contributing to food texture and mouthfeel, and its removal often results in a loss of quality and consumer acceptability. Thus, developing effective fat replacers is essential to compensate for the loss of fat-related properties and enhance the acceptability of a low-fat or non-fat product. Plant-based proteins, such as modified legume proteins, offer a promising fat alternative due to functionalities including water solubility, water and oil holding capacity, gelation, and emulsification properties. Leveraging these attributes, this study investigates the enzymatic modification of lentil protein isolates (LPI) to produce polypeptides with enhanced functional properties for application as fat replacers in non-fat yogurts. LPI was hydrolyzed using Alcalase at varying enzyme-to-substrate ratios (1/100 to 1/2000) and hydrolysis times (2 to 240 mins), and the resulting polypeptides were characterized based on their functional properties. The enzymatic hydrolysis significantly improved the functional properties of LPI, where the extent of improvement was dependent on hydrolysis conditions. Further, selected polypeptides were incorporated into non-fat milk to form yogurt gels using 2.5% glucono-delta-lactone, and their rheological properties were compared to unfortified non-fat and whole milk yogurts. Notably, the rheological analysis suggested that polypeptide-fortified yogurts exhibited enhanced gel strength compared to unfortified non-fat yogurts and achieved textural characteristics comparable to whole milk yogurts. This demonstrates the potential of lentil polypeptides, expanding the research on plant-based functional ingredients and offering a novel approach to fat replacement.
Importance
The rising prevalence of obesity is a major public health concern, contributing to the occurrence of chronic diseases. Excessive calorie intake, particularly from full-fat products, is one of the primary factors in the obesity epidemic, increasing consumer demand for healthier low-fat or non-fat food products. However, removing or reducing fat from food products imparts inferior texture, viscosity, appearance, and flavor, leading to reduced consumer acceptability. This highlights the need for effective fat replacers that could provide some or all of the functions of fat while yielding fewer calories in low-fat food products. This research aims to create novel fat replacers that are low in calories but also cost-effective with excellent functionalities across diverse food applications.