Effects of Ultrasound Processing on Physicochemical Parameters, Antioxidants, and Color Quality of Bayberry Juice

Xiamin Cao,Yongling Wang,Xiaojian Zheng,Chunfang Cai

doi:10.1155/2019/7917419

Abstract

Effects of ultrasound on physicochemical parameters, ascorbic acid, anthocyanins, polymeric color (PC), 5-hydroxymethylfurfural (HMF), browning degree (BD), color, and superoxide dismutase (SOD) activity of bayberry juice were investigated. Treatments were carried out at amplitude levels from 20 to 100% of total input power (600 W) at 20 kHz for 2–10 min. The results showed that no notable differences in pH, total soluble solids, titratable acidity, and yellowness b∗ values were found in ultrasound-treated samples. The HMF, PC, BD, and L∗ values of bayberry juice obviously increased with enhancing ultrasonic intensity and treatment time. The ascorbic acid exhibited no notable changes after ultrasound treatment at lower intensity levels for short time, while anthocyanins showed an increasing tendency. With increasing ultrasonic intensity and time, antioxidants gradually decreased. Furthermore, the SOD activity apparently increased at short-time treatment and then decreased with ultrasound processing extension.

Highlights

Bayberry (Myrica rubra Sieb. et Zucc.) is one of the most popular berry fruits in Chinese markets because of its sweetsour taste, pleasant aroma, and attractive color [1].Bayberry fruits with high content of polyphenols are considered antioxidants and demonstrated to have benecial health e ects on humans [2,3,4,5,6]
Effects of Ultrasound on Ascorbic Acid. e initial content of ascorbic acid in fresh juice was 22.82 mg/100 mL. 25.16% of ascorbic acid decreased in the samples after TP treatment, indicating that ascorbic acid was highly thermosensitive
No significant differences in pH, °Brix, TA, and b∗ values were observed in ultrasound-treated bayberry juice. e BD, polymeric color (PC), HMF, and L∗ values of bayberry juice obviously increased after ultrasound treatment

Summary

Introduction

Bayberry (Myrica rubra Sieb. et Zucc.) is one of the most popular berry fruits in Chinese markets because of its sweetsour taste, pleasant aroma, and attractive color [1].Bayberry fruits with high content of polyphenols are considered antioxidants and demonstrated to have benecial health e ects on humans [2,3,4,5,6]. Erefore, the processed products of bayberry for shelf-life extension are of high commercial and economic importance. Bayberry fruits are commercially processed into wine, jam, or juice by di erent thermal technologies for microorganism and endogenous enzyme inactivation [8]. Ese bayberry products can reach a widespread market and longer shelf-life, but they su er from losses of nutritional compounds and changes of sensory quality during thermal processing because of their heat sensitivity [4, 6]. With the increase in minimally processed and fresh food products demanded by consumers, it is necessary to develop innovative techniques which use minimal heat and maximally retain food quality [7]. Attributed to lower degradation of nutrition and quality [15, 16], ultrasound is increasingly studied for the processing of fruit juice and puree, such as grapefruit juice [17], soursop juice [16], gourd juice [18], pear juice [19], blackberry juice [20], avocado puree [21], raspberry puree [22], orange juice [23, 24], tomato juice [25], apple juice [26], and strawberry juice [27] in recent years

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Results

Conclusion