Improvement of physicochemical properties of food by phytocompounds-loaded nanoemulsions

Abstract

Nanoemulsions are kinetically stable colloidal systems that have improved functional properties compared to conventional emulsions. In the last decade, there has been a growing interest in the application of nanoemulsions in the food industry, due to their better stability to gravitational separation and aggregation processes, higher liquid droplet interface area and optical transparency. Furthermore, nanoemulsions can be successfully applied for the effective incorporation of bioactive compounds (BCs) such as, phenolics, vitamins, carotenoids, terpenes, and aromatic compounds. The phytocompound-loaded nanoemulsions can be incorporated into different food matrices resulting in the improvement of numerous physicochemical properties of the final products. This work aimed to give a comprehensive overview of recent developments in the applications of phytocompound-loaded nanoemulsions in the improvement of food physico-chemical properties.Physicochemical properties such as food stability, colour, texture, flavour profile, solubility, and stickiness play a key role in the food product’s sustainability, acceptability and perception. The physical properties that consumers most often pay attention are the colour and consistency of the product. Capsaicin and curcumin, very popular natural colorants, have lipophilic nature and low processing stability limiting their application. By the formation of capsaicin-loaded nanoemulsions, its droplet size and colour can be improved, enabling the use of capsaicin nanocomplexes in functional food products with sustainable colour. The addition of the quercetin-loaded nanoemulsions in the chicken pâtés showed excellent consumer acceptability in terms of odour, taste and colour and, at the same time, protects this product from lipid oxidation. Milk enriched with vitamin D3 loaded (o/w) nanoemulsions showed good stability to particle growth and gravitational separation of whole-fat milk. Moreover, encapsulation of lipophilic phytocompounds to nanoemulsions allows their incorporation into highly transparent or slightly turbid products without altering the product’s visual appearance. For example, nanoemulsions containing cinnamon essential oil and ascorbic acid improve physical stability, prevent sedimentation and delay degradation of total phenolics and ascorbic acid of cloudy apple juice. The encapsulation of various phytocompounds within nanoemulsions represents an interesting approach that offers novel solutions for their use in the modern food industry.