Relationship between Molecular Structure and Heat-Induced Gel Properties of Duck Myofibrillar Proteins Affected by the Addition of Pea Protein Isolate

Abstract

This paper investigates the relationship between the molecular structure and thermally induced gel properties of duck myofibrillar protein isolate (DMPI) as influenced by the addition of pea protein isolate (PPI). The results showed that b* value of the gels increased; however, a* value decreased with the increase of PPI content (p < 0.05). The whiteness of the gels decreased significantly with the addition of pea protein compared with 0% vs. 0.5% addition. Nuclear magnetic resonance tests showed the area of immobilized water also increased with increasing PPI addition (0–2%), thus consistent with the increased water-holding capacity (p < 0.05). The penetration force of the gels increased with increasing PPI addition (p < 0.05), while the storage modulus and loss modulus of the gels were also found to increase, accompanied by the transformation of the α-helix structure into β-sheet, resulting in better dynamics of gel formation. These results indicated the gel-forming ability of DMPI, including water retention and textural properties, improves with increasing PPI addition. Principal component analysis verified these interrelationships. Thus, pea protein could improve the properties of duck myofibrillar protein gels to some extent and improve their microstructure, potentially facilitating the transition from a weak to a non-aggregated, rigid structure.

The Impacts of Different Pea Protein Isolate Levels on Functional, Instrumental and Textural Quality Parameters of Duck Meat Batters

“…Similar results were reported in our previous study that the water-holding capacity of duck myofibrillar protein gels could be enhanced by the addition of PPI (0.5–2%), since the free water content is inversely proportional to the water-holding capacity [ 10 , 41 ]. Initially, T 2b , T 21′ and T 21 relaxation times were significantly reduced; PT 21′ and PT 21 peak ratios were increased and PT 22 was significantly reduced, respectively, which implied an increase in the immobilized water content.…”

“…Pea protein is known to be highly digestible, hypoallergenic and it contains almost no ingredients that cause intolerance, as it is gluten- and lactose-free. In addition, pea protein has good emulsification and other functional properties [ 9 ], and our recent study showed that partial addition improved the properties of duck myofibrillar protein gels and improved their microstructure [ 10 ]. The reduction of fat and its replacement with texturized pea protein was feasible, with no detrimental impact on the acceptability of dry, fermented sausages [ 11 ] and low-fat frankfurters [ 12 ].…”

Effect of Malondialdehyde-induced Oxidation Modification on Physicochemical Changes and Gel Characteristics of Duck Myofibrillar Proteins

“…As seen, three typical peaks were found, therein a peak appeared in 20 -96 ms, a larger peak emerged at 131-446 ms, and a peak existed after 800 ms. In our previous paper, DMPs gel generally showed three peaks in the fitted NMR relaxation curve, which corresponded to moderate immobilized water, immobilized water, and free water [28].…”

Effect of Malondialdehyde-Induced Oxidation Modification on Physicochemical Changes and Gel Characteristics of Duck Myofibrillar Proteins

“…Figure 6 shows the effect of malondialdehyde concentration on the changes in relaxation time (T 2 ) of the gels of DMPs. As shown in the figure, three typical peaks were found, with one peak appearing at 20–96 ms, a larger peak at 131–446 ms, and another peak after 800 ms. Our previous paper found that DMP gels generally show three peaks in the fitted NMR relaxation curves, corresponding to moderately immobilized water, immobilized water, and free water, respectively [ 28 ]. That is, T 21 represents moderate immobilized water with peaks between 20 and 96 ms, T 22 represents immobilized water with peaks between 131 and 446 ms, and T 23 represents free water with peaks after 800 ms.…”