096: Upcycling Polyphenols From Peanut Skin Into Foods via an Improved pH-Driven Method

Introduction

Polyphenols are bioactive compounds with numerous health benefits, including antioxidant, anti-inflammatory, and antimicrobial properties, making them valuable for enhancing the nutritional profile of food systems. However, many polyphenols are highly sensitive to processing conditions, leading to significant losses in their stability and bioactivity. Peanut skin, a byproduct of the peanut industry, is a rich source of polyphenols, yet it is often discarded, contributing to agricultural waste. Incorporating polyphenols from peanut skin into food systems not only capitalizes on their health-promoting properties but also offers an opportunity to upcycle this underutilized byproduct, reducing waste and promoting sustainability.

Methods

In this study, we refined the pH-driven method to address challenges associated with processing highly pH-sensitive polyphenols, such as quercetin, into nanoemulsions. Key optimizations included minimizing oxygen exposure and reducing processing times to preserve polyphenol stability. The improved post-pH-driven (PPD) method achieved an encapsulation efficiency exceeding 95% for quercetin, demonstrating its robustness and scalability. To illustrate its versatility, the PPD method was successfully applied to upcycle polyphenols extracted from peanut skin into nanoemulsions using a plant-based food model.

Results

Comparative analysis revealed that the PPD method outperformed the conventional water-based approach, retaining 1.8 times more total polyphenolic content. Furthermore, nanoemulsions produced via the PPD method exhibited significantly enhanced antioxidant properties, with DPPH and ABTS radical scavenging activities increasing by 3.7 and 2.8 times, respectively.

Significance

These findings highlight the PPD method's potential as a sustainable and efficient approach for integrating polyphenols into food systems. By combining upcycling of plant byproducts with improved processing strategies, this method not only enhances polyphenol functionality but also contributes to reducing food waste and promoting resource efficiency in food production.

Authors: Xiping Gong, Minghe Wang, Hualu Zhou