Alternative Processing Options for Improving the Proteins Functionality by Maillard Conjugation

Abstract

Conjugation of the proteins with carbohydrates, occurring in the early stages of the Maillard reactions, received increased attention because of the high potential to ensure the improvement of the biological activity and functional properties of the proteins of different origins. The Maillard conjugates are conventionally formed through wet or dry heating, but the use of alternative technologies involving ultrasound, microwave, pulsed electric fields, high-pressure, or electrodynamic treatments appears to be efficient in accelerating the reaction steps and limiting the formation of toxic compounds. An overview of the mechanisms of these processing technologies, the main parameters influencing the Maillard conjugate formation, as well as their advantages and disadvantages, is provided in this paper. Different strategies employing these alternative technologies are reported in the literature: as pretreatment of the proteins, either alone or in admixture with the carbohydrates, followed by conventional heating, as a single alternative treatment step, or as a combination of heating and alternative processing. The desired functional properties of the proteins can be achieved by selecting the appropriate processing strategy and optimizing the reaction parameters. Moreover, alternative technologies can be exploited to obtain Maillard conjugates with remarkable biological activity in terms of antioxidant, antimicrobial, antihypertensive, anti-inflammatory, antimutagenic, or bifidogenic properties.

Ultrasound-Assisted Maillard Conjugation of Yeast Protein Hydrolysate with Polysaccharides for Encapsulating the Anthocyanins from Aronia

“…Thus, the GD of the conjugate prepared with dextran was higher by about 13% than the SYH:MD conjugate (Table 2). US treatment for 5 min was able to provide a similar GD with what conventional heating was able to reach it after 100 min, most probably due to acoustic cavitation that accelerated the molecular motion of the proteins, leading to the disruption of quaternary and tertiary structure of protein, which in the end promoted the exposure of reactive groups [6,21]. In addition, the energy that resulted during US exposure accelerated the grafting between reactants, as the reactive groups of SYH and polysaccharides were in closer proximity [21].…”

“…Usually, the Maillard reaction leads to the formation of organic acids, such as formic and acetic acids, and the reduction in the amino-groups of the proteins/peptides with consequences on the pH that decreases [19]. After 5 min of US exposure, the pH reached a minimum in both samples, while further exposure led to the pH increase, an indication of peptides denaturation that favoured the exposure of hidden amino groups causing the increase of pH [6]. Compared to conventional heating, the pH values of the US conjugated samples were slightly lower indicating the higher Maillard reaction rate when using US.…”

“…The Maillard reaction is a covalent glycation strategy for producing proteinpolysaccharide conjugates, and one of the most efficient methods for improving proteins functionality in terms of emulsifying, foaming, solubility, and antioxidant properties [6,7]. These properties are promoted when the Maillard reaction is performed under controlled conditions, regarding reactants characteristics, ratio between reactants, reaction temperature, and pH.…”

“…In recent years, alternative treatments have demonstrated the huge potential for replacing or complementing the conventional heating due to their ability of enhancing the functionality of proteins while limiting the formation of toxic compounds. Among them, ultrasound treatment (US) is one of the most cost-effective methods for promoting and accelerating the Maillard conjugation [6]. However, the use of ultrasound and the Maillard reaction for improving the anthocyanins encapsulation potential of milk proteins has been reported recently by [7].…”

Effect of low frequency ultrasound on lactose‐protein interactions in protein solution containing different casein to whey protein ratios

“…The lactose‐protein complex formation was found to involve Schiff's base formation between the free amino groups and lactose, which then undergo Amadori rearrangement to give enol and keto forms (Dumitrașcu et al ., 2023). These lactose‐protein complexes can be covalently linked, and with prolonged sonication, they can break, allowing for protein‐protein re‐aggregation to occur under 10 min of sonication (Chandrapala et al ., 2011).…”