BACKGROUNDAmidst the rising trend of healthy eating, there is a surge in demand for low‐fat food options. Within the realm of fat substitutes, modified proteins have shown the most effective ability to replace fat due to their nutritional attributes and functional properties. This study focused on the development of a fat substitute for low‐fat whipping cream using the conjugate of ultrasonic mung bean protein and mung bean starch.RESULTSOur findings revealed that the emulsifying properties and solubility of the conjugates were significantly superior to those of mung bean protein alone (P < 0.05). This enhancement was attributed to a smaller particle size, depolymerization of protein molecules and increased total sulfhydryl content, especially the conjugate formed by 60 min ultrasonic mung bean protein and mung bean starch (UMBP60+MS). Incorporating UMBP60+MS as a fat substitute at a 10% ratio in the formulation of low‐fat whipping cream resulted in a product with enhanced apparent viscosity, superior environmental stability, and commendable sensory characteristics. Moreover, the fat digestion rate was significantly reduced by 13.5% with the 10% substitution. This 10% substitution also endowed the whipping cream with the most desirable β′‐type crystal morphology and the most stable three‐dimensional network structure. An intimate encapsulation of fat globules by the conjugate was observed using cryogenic scanning electron microscopy.CONCLUSIONThe UMBP60+MS conjugate emerged as an effective fat substitute in whipping cream, providing significant contributions to addressing health concerns in the food industry. © 2024 Society of Chemical Industry.