Synergistic Effect of Laccase and Sugar Beet Pectin on the Properties of Concentrated Protein Emulsions and Its Application in Concentrated Coconut Milk

Abstract

Concentrated coconut milk (CCM), a raw material from coconut products, is extremely unstable because of its high oil content (>30%). In this study, three model emulsions—primary emulsions stabilized by coconut proteins only, secondary emulsions stabilized by the conjugation of sugar beet pectin (SBP) and coconut protein, and laccase-treated secondary emulsions—were prepared to investigate the effects of different factors (coconut proteins, coconut proteins + SBP, laccase-treated emulsions) on the stability of model emulsions and the application of this method to real CCM. The stability of the emulsions was evaluated based on their interfacial tension, zeta potential, particle size distribution, rheological properties, and the assembly formation of SBP and coconut protein at the oil–water interface. Results showed that addition of SBP or laccase can increase the viscosity and reduce the interfacial tension of the emulsion, and the effect was concentration dependent. Zeta potential of the emulsion decreased with the increase of protein (from −16 to −32 mV) and addition of SBP (from −32 to −46 mV), and it was reduced when laccase was added (from −9.5 to −6.0 mV). The secondary emulsion exhibited the narrowest particle size distribution (from 0.1 to 20 μm); however, laccase-catalyzed secondary emulsions showed the best storage stability and no layering when the laccase content reached 10 U/100 g. Confocal laser scanning microscopy (CLSM) revealed that protein was adsorbed on the oil–water interface and SBP distributed in the continuous phase could undergo oxidative crosslinking by laccase. These results show that the stability of the concentrated emulsion can be effectively improved by adding SBP and laccase.

Preparation and Characterization of a Modified-β-Cyclodextrin/β-Carotene Inclusion Complex and Its Application in Pickering Emulsions

“…The sample was stored at room temperature for 1 week to observe the stratification of the emulsion. The creaming index (CI, %) was calculated as follows: 25 = × CI (Height of the serum layer/Total height of the emulsion) 100%…”

Applications and immobilization strategies of the copper-centred laccase enzyme; a review

“…Laccase has found application in food industry as a food additive for stabilization of beverages, wines and beers [ 266 , 267 , 268 ], clarification of fruit juices [ 269 , 270 , 271 ], baking [ 272 , 273 , 274 , 275 ], sugar beet pectin gelation [ 276 ], and improvement of food sensory parameters [ 277 ]. It is also used in the detection of phenolic compounds in beverages, wines and beers [ 278 ], as well as bioremediation of food industry waste water.…”

Circular Economy Approaches in the Palm Oil Industry: Enhancing Profitability through Waste Reduction and Product Diversification

“…Anaerobic digestion technology has revolutionized the way palm oil mills manage POME, turning it into biogas and contributing to a more sustainable energy landscape [134,135]. The extraction of bioactive compounds from palm oil and its by-products has paved the way for the creation of high-value functional ingredients, while biobased chemicals and green cosmetics have emerged as sustainable alternatives in various industries [136][137][138][139][140][141].…”