Encapsulation of grape seed bioactives using food by-product matrices

Overview

This research proposes a novel encapsulation approach to fortify beverages with bioactive compounds derived from grape seed by-products. The technology leverages fibre, polyphenols, and minerals extracted from grape seeds using supercritical fluid extraction (SCFE) to produce dry powders soluble in polar solvents. By encapsulating these bioactives within polysaccharide and protein matrices sourced from food by-products, the solution addresses key challenges in functional beverage development, including thermal stability, pH tolerance, and preservation of sensory characteristics.

The approach builds on prior work with olive seed by-products, including fibre powders, oily extracts, and xylooligosaccharide (XOS) prebiotics, extending the encapsulation methodology to grape-derived bioactives rich in catechin, epicatechin, resveratrol, quercetin, and essential minerals.

Technical specifications

Core encapsulation approach:

• Utilises β-glucans and proteins with filmogenic properties extracted from food by-products as encapsulating agents
• Targets bioactive compounds including antioxidants, polyphenols, and essential oils sensitive to temperature, pH, and digestive conditions
• Designed to maintain bioactive integrity through thermal processing at 90°C
• Preserves organoleptic characteristics of the fortified end product

Grape seed bioactive profile:

• Polyphenols: catechin, epicatechin, resveratrol, dihydroxybenzoic acid, quercetin
• Minerals: calcium, potassium, magnesium, sodium, phosphorus, iron, zinc, copper, manganese
• Processing via supercritical fluid extraction (SCFE) before or after extraction
• Output format: dry powder soluble in polar solvents

Prior validation basis:

• β-glucan has been previously tested as an encapsulating agent to improve prebiotic stability under gastrointestinal conditions with satisfactory results
• Established expertise in encapsulating olive seed fibre, oily extracts, and XOS prebiotics

Technology readiness level

This research is at an early-to-mid stage of development. The encapsulation methodology draws on validated prior work with β-glucans and food by-product matrices, including demonstrated stability improvements for prebiotics under gastrointestinal conditions. Future validation will focus on assaying polysaccharides and proteins with filmogenic properties for encapsulating grape-derived bioactive extracts, with particular emphasis on maintaining stability against environmental stressors including temperature, pH, and digestive conditions. The goal is to ensure bioactive agents reach their site of action intact, enabling functional beverage applications.