Enzymatic cross-linking of pectin in a high-pressure foaming process

Abstract

The enzyme laccase is a copper-containing oxidoreductase with the ability to oxidize a wide range of substrates, such as ferulic acid. Thus, the ferulic acid-containing sugar beet pectin (SBP) can be crosslinked through laccase-mediated oxidation. As cross-linking increases viscosity, it could be applied to stabilize SBP-containing foams. In this study, laccase-mediated cross-linking of SBP was investigated under conditions of a high-pressure foaming process. Shear, presence of CO 2 , and pressure were simulated in a rheometer equipped with a high-pressure cell. At rest, addition of laccase to SBP solution led to the formation of a stiff gel. Application of shear upon mixing of laccase and SBP solution decreased the storage modulus with increasing shear duration and shear rate. This can be attributed to the formation of a fluid gel. However, when shear was stopped before all available ferulic acid groups were cross-linked, a stronger and more coherent network was formed. Pressure exerted by CO 2 did not affect cross-linking.Additionally, this approach was tested in a stirred high-pressure vessel where SBP was foamed through CO 2 dissolution under pressure and shear followed by controlled pressure release. While pure SBP foam was highly unstable, addition of laccase decelerated collapse. Highest stability was reached when laccase and SBP were mixed prior to depressurization. At the point of foam formation, the continuous phase was thereby viscous enough to increase foam stability. At the same time, continuation of cross-linking at rest caused gel templating of the foam structure.

Latent Benefits and Toxicity Risks Transmission Chain of High Dietary Copper along the Livestock–Environment–Plant–Human Health Axis and Microbial Homeostasis: A Review

“…In addition, the enzyme laccase (EC 1.10.3.2), which is a multi-Cu oxidoreductase with the ability to oxidize a wide range of substrates, is combined with several Cu ions and synthesized by plants such as Arabidopsis . − Hirayama et al also reported that Cu is necessary for the ethylene signaling process and found that responsive to antagonist 1 ( RAN1 ) gene it acts by delivering Cu to create functional hormone receptors in Arabidopsis . Marmiroli et al.…”

Advances in Injectable In Situ-Forming Hydrogels for Intratumoral Treatment

“…Active enzymes for injectable in situ-forming hydrogels include laccases, horseradish peroxidase (HRP), transglutaminases (TGases, protein-glutamine gamma-glutamyltransferase), tyrosinase (Tyr), and lysyl oxidase coupled with hydrogen peroxide (H 2 O 2 ) to support the reaction [61][62][63][64][65][66][67][68][69]. Enzymatic-mediated crosslinking using HRP induces the binding of aniline, phenol, and its derivative tyramine in the presence of H 2 O 2 [70][71][72][73]. Enzymaticmediated crosslinking forms strong covalent bonding, with reactions occurring in less than 10 min.…”

“…port the reaction [61][62][63][64][65][66][67][68][69]. Enzymatic-mediated crosslinking using HRP induces the binding of aniline, phenol, and its derivative tyramine in the presence of H2O2 [70][71][72][73]. Enzymatic-mediated crosslinking forms strong covalent bonding, with reactions occurring in less than 10 min.…”

Effects of natural waxes on the interfacial behavior, structural properties and foam stabilization of aerated emulsions

“…Aerated emulsions have widespread applications in food products including whipped cream, ice cream and aerated chocolate, due to their large specific surface area, small specific gravity, and excellent mechanical properties from liquid to solid. [1][2][3][4] Specifically, aerated emulsions reduce the calorific value and the cost while providing the desirable luxurious texture. 5,6 However, the relatively poor stability of aerated emulsions remains a major challenge due to their inherent thermodynamic instability as well as their complex structure at multiple length scales.…”