Effect of spray drying conditions on the physical characteristics, amino acid profile, and bioactivity of blood fruit ( Haematocarpus validus Bakh.F. Ex Forman) seed protein isolate

Abstract

The demand for plant-based proteins has significantly increased as compared to meat-based proteins for a variety of reasons like increasing vegetarianism, meat analogs, and easy digestion. However, consumer acceptance for plant-based proteins is low due to beany taste and off-flavors. Therefore, this study aims to eliminate beany taste and off-flavors of blood fruit seed protein by probiotic fermentation and spray drying. The probiotic fermented and non-fermented protein isolate slurry samples were spray-dried at 160°C and 180°C to get a shelf-stable free flow protein powder. The probiotic count for the fermented spray dried samples at both temperatures was found less than 5 Log CFU/g; hence, the protein isolates are not probiotic in nature. The protein quality parameters of blood fruit seed protein were assessed. The results revealed that all the quality parameters were found better at 160°C, thus obtaining a superior quality blood fruit seed protein isolate. Practical applications Blood fruit seed protein is rich in essential amino acids and bioactive peptides. The essential amino acids of blood fruit seed protein are higher than the adult daily recommended allowance. The amino acids of blood fruit seed protein possess better digestibility index, digestible indispensable amino acid score and protein digestibility corrected amino acid score compared to soy protein. But the consumer acceptance is low due to its beany off-flavor. However, this study revealed that the lactic acid fermentation and spray drying reduced the off-flavor of blood fruit seed protein to a greater extent. The fermentation and spray-drying improved the overall functional properties of blood fruit seed protein isolate. Hence, the new plant protein isolate could be used as an emulsifier, a gelling and foaming agent, a humectant, and an encapsulating material for various food and pharmaceutical applications.