Review on the release mechanism and debittering technology of bitter peptides from protein hydrolysates

Abstract

Recent scientific evidence indicates that protein hydrolysates contain bioactive peptides that have potential benefits for human health. However, the bittertasting hydrophobic peptides in protein hydrolysates negatively affect the sensory quality of resulting products and limit their utilization in food and pharmaceutical industries. The approaches to reduce, mask, and remove bitter taste from protein hydrolysates have been extensively reported. This review paper focuses on the advances in the knowledge regarding the structure-bitterness relationship of peptides, the release mechanism of bitter peptides, and the debittering methods for protein hydrolysates. Bitter tastes generating with enzymatic hydrolysis of protein is influenced by the type, concentration, and bitter taste threshold of bitterness peptides. A "bell-shaped curve" is used to describe the relationship between the bitterness intensity of the hydrolysates and the degree of hydrolysis. The bitter receptor perceives bitter potencies of bitter peptides by the hydrophobicity recognition zone. The intensity of bitterness is influenced by hydrophobic and electronic properties of amino acids and the critical spatial structure of peptides. Compared to physicochemical debittering (i.e., selective separation, masking of bitter taste, encapsulation, Maillard reaction, and encapsulation) and other biological debittering (i.e., enzymatic hydrolysis, enzymatic deamidation, plastein reaction), enzymatic hydrolysis is a promising debittering approach as it combines protein hydrolyzation and debittering into a one-step process, but more work should be done to advance the knowledge on debittering mechanism of enzymatic hydrolysis and screening of suitable proteases. Further

Advances in separation and identification of biologically important milk proteins and peptides

“…In the past, the studies have been carried out to reduce bitter taste of casein hydrolysates, which are important nutrition additives, by applying various exo-and endopeptidases and processing methods [104]. For example, specific enzymatic techniques have been applied [105,106], and exopeptidases have been used that cleaved the protein at the site adjacent to hydrophobic amino acids or cut off hydrophobic amino acids from protein terminus [107,108]. Recently, the combination of two separation techniques has been used in 2D-LC arrangement [109], that is, SEC and RPLC for the characterization of bitter peptides in casein hydrolysates.…”

Debittering of salmon frame protein hydrolysate and plastein using Maillard reaction as affected by types of sugar

“…Furthermore, liposomal encapsulation of aforementioned hydrolysates was efficient to reduce the bitterness of protein hydrolysates (Sharma et al ., 2023). Use of Maillard reaction could be one of potential ways, which not only reduces the bitterness but also is capable of imparting the better flavour with desirable caramel odour as that found in soy sauce along with umami taste (Liu et al ., 2022).…”

“…Maillard reaction is a non‐enzymatic browning reaction, which is characterised as a complicated interaction between carbonyl groups of reducing sugars and amino groups of free amino acids, peptides or proteins (Yu et al ., 2018; Liu et al ., 2022). It occurs commonly during the preparation and storage of food, and is crucial for the development of flavour in food.…”

Germinated chickpea protein ficin hydrolysate and its peptides inhibited glucose uptake and affected the bitter receptor signaling pathway in vitro

“…21 Enzymatic hydrolysis of plant-based proteins has been shown to both increase and decrease the bitter taste of the hydrolysate, depending on the hydrolysis conditions and the composition of the isolate. 22 While there is some data regarding the bitter taste of peptides and plant-based protein hydrolysates, there is limited data on the effect of its bitterness on markers of T2D in in vitro systems. It is therefore necessary to describe the relationship between bitterness and healthrelated potential.…”