# Enhancing Antioxidant and Flavor of Xuanwei Ham Bone Hydrolysates via Ultrasound and Microwave Pretreatment: A Backpropagation Artificial Neural Network Model Prediction

## TL;DR

This study uses ultrasound and microwave pretreatment to improve the antioxidant properties and flavor of Xuanwei ham bone hydrolysates.

## Contribution

A novel BP-ANN model predicts optimal pretreatment conditions to enhance antioxidant activity and flavor profile of Xuanwei ham bone hydrolysates.

## Key findings

- Ultrasound and microwave pretreatment increased the degree of hydrolysis to 28.33, closely matching the model prediction of 27.69.
- UMH hydrolysates showed the highest antioxidant activity and inhibited lipid oxidation effectively.
- GC-MS analysis showed removal of bitter compounds and formation of aromatic volatile compounds in UMH.

## Abstract

This study aimed to produce the hydrolysates of Xuanwei ham bone using enzymatic hydrolysis assisted by microwave and ultrasound pretreatment. A back propagation artificial neural network (BP-ANN) model was utilized to predict the optimal conditions, which involved 15 W/g bone for 15 min of ultrasound pretreatment and 5 W/g bone for 30 min of microwave pretreatment, achieving the highest degree of hydrolysis (DH). The model predicted a DH of 27.69, closely aligning with the experimentally measured actual DH of 28.33. DPPH radical scavenging and TBARS demonstrated that hydrolysates prepared by ultrasound combined microwave pretreatment (UMH) exhibited the highest antioxidant activity and significantly inhibited lipid oxidation. GC-MS analysis revealed that the UMH showed removal of bitter volatile flavor compounds, such as o-Cresol and m-Cresol, the retention of aromatic volatile compounds, such as 2-pentylfuran, formation of new aromatic volatile compounds such as 3-methylbutanal, and the reduction in certain aldehyde and ketone compounds. Pearson correlation analysis elucidated that the reduction in aldehyde and ketone compounds was positively linked to the enhanced antioxidant capacity of UMH. The results obtained hold substantial significance for enhancing the added value of Xuanwei ham within the food industry.