Encapsulation of Grape (Vitis vinifera L.) Pomace Polyphenols in Soybean Extract-Based Hydrogel Beads as Carriers of Polyphenols and pH-Monitoring Devices

Abstract

In this work, novel bio-based hydrogel beads were fabricated by using soybean extract as raw waste material loaded with Lambrusco extract, an Italian grape cultivar. The phenolic profile and the total amount of anthocyanins from the Lambrusco extract were evaluated before encapsulating it in soybean extract-based hydrogels produced through an ionotropic gelation technique. The physical properties of the produced hydrogel beads were then studied in terms of their morphological and spectroscopic properties. Swelling degree was evaluated in media with different pH levels. The release kinetics of Lambrusco extract were then studied over time as a function of pH of the release medium, corroborating that the acidity/basicity could affect the release rate of encapsulated molecules, as well as their counter-diffusion. The pH-sensitive properties of wine extract were studied through UV-Vis spectroscopy while the colorimetric responses of loaded hydrogel beads were investigated in acidic and basic solutions. Finally, in the framework of circular economy and sustainability, the obtained data open routes to the design and fabrication of active materials as pH-indicator devices from food industry by-products.

Binary Hydrogels: Induction Methods and Recent Application Progress as Food Matrices for Bioactive Compounds Delivery—A Bibliometric Review

“…However, the proper selection of hydrogel building components is critical because anthocyanins may be degraded rather than protected, as observed in the studies of Kopjar et al [193], in which the fortification of anthocyaninsloaded pectin hydrogel with apple fibers caused a substantial degradation in the retention of the anthocyanins. Furthermore, hydrogel loaded with anthocyanins can also be utilized as a colorimetric pH indicator to monitor, for example, the freshness of food products [166,194,195].…”

Alginate Microbeads Containing Halloysite and Layered Double Hydroxide as Efficient Carriers of Natural Antimicrobials

“…Microencapsulation is an efficient drug delivery technique that offers numerous benefits over direct intake or conventional delivery systems; these advantages include control of the release rate, protection of the active ingredient from degradation, and targeted delivery [ 1 , 2 ]. Microencapsulation has not only proven to be successful in pharmaceuticals, medicines and cosmetics but also in the food industry, where, in addition to controlling the release rate of antimicrobials and their targeted dispensing, it can also be used to absorb harmful substances and odours and prolongate the storage of volatile compounds, as well as to provide information on the quality of the item through a ‘smart’ response [ 3 ].…”