High pressure control of protein structure and functionality

Abstract

Purpose -This article aims to consider the use of high pressure processing in order to gain functional advantages through proteins structure control. High pressure processing has been used to produce high-quality food with extended shelf life and could also be used to modify foods functionality. Design/methodology/approach -The effect of high pressure on protein structure and functionality is looked at and comparisons are made with heat effect in places. b-lactoglobulin and whey proteins are mainly taken as examples.Findings -A controlled partial protein unfolding through mild high pressure processing could lead to a range of intermediate molecular structures. These are distinct from the native and completely unfolded structure and have been referred to as molten globules. The partly unfolded molecular states, hence, are postulated to have increased functionality and could be interesting for the food industry. Originality/value -The opportunity and challenges represented by these theoretical elements are discussed. In particular, the effect of protein concentration and aggregation is emphasised.

Enzymatic hydrolysis of anchovy fine powder at high and ambient pressure, and characterization of the hydrolyzates

“…The elution profiles of 120 g L −1 AFP suspension after the treatments at ambient pressure and 300 MPa without enzymes were mostly similar, with two major protein peaks eluting at 10 and 16.5 min. However, minor peaks eluting at 13–15 and 20–23 min were found in the case of the blank treated at 300 MPa, which seemed to indicate that the high‐pressure treatment slightly modified the structure of dissolved proteins of AFP suspension via controlled partial unfolding, followed by aggregation of the resultant molten globules . As can be seen in Fig.…”

“…However, minor peaks eluting at 13-15 and 20-23 min were found in the case of the blank treated at 300 MPa, which seemed to indicate that the high-pressure treatment slightly modified the structure of dissolved proteins of AFP suspension via controlled partial unfolding, followed by aggregation of the resultant molten globules. 26,27 As can be seen in Fig. 3, the retention time (RT) of peptide peaks decreased greatly with the enzymatic hydrolysis of AFP suspension at ambient pressure and 300 MPa.…”

Preparation and Characterization of a Hypoglycemic Complex of Gallic Acid–Antarctic Krill Polypeptide Based on Polylactic Acid–Hydroxyacetic Acid (PLGA) and High-Pressure Microjet Microencapsulation

“…With a further increase in humidity, GA-AKP-Ns combined with water molecules in large quantities, causing the PLGA to degrade and preventing it from providing a dense hydrophobic layer. This phenomenon can be improved by adjusting the ratio of polymers in PLGA [27]. In summary, the nanocapsule structure improves the hygroscopic stability of the raw material.…”

“…With increasing pressure, the molecular loading energy in the system became too high, accelerating Brownian motion and reducing emulsion stability, which affects the embedding effect. In addition, high pressure may have altered the peptide structure, causing peptide molecules to polymerize with each other [27], hindering binding with PLGA and reducing peptide embedding efficiency. In conclusion, the optimal choice was a jet pressure of 150 MPa.…”

Influence of pH on viscoelastic properties of heat-induced gels obtained with a β-Lactoglobulin fraction isolated from bovine milk whey hydrolysates

“…Proteins converting to the molten globule state usually show little change in the secondary structure and, hence conserve native-like far-UV spectra. However, b-Lg is an exception and shows a strong change in the secondary structure upon conversion to the molten globule state (Aouzelleg, 2014).…”