Effect of Different Temperature-Controlled Ultrasound on the Physical and Functional Properties of Micellar Casein Concentrate.

Bong Song,Ning Xie,Baojia Yang,Yumeng Zhang,Jiaping Lv,Xiaoyang Pang,Shuwen Zhang,Panpan Zhu

doi:10.3390/foods10112673

Abstract

Micellar casein concentrate (MCC) is a novel dairy ingredient with high protein content. However, its poor functional properties impair its potential for further application, highlighting the importance of using innovative processing methods to produce modified MCC, such as ultrasound (US). This work investigated the impact of US on the physical and functional properties of MCC under temperature-controlled and -uncontrolled conditions for different time intervals. Under temperature-controlled ultrasound (TC-US) treatment, a reduction was found in the supernatant particle size of casein micelles. Soluble calcium content and hydrophobicity increased following ultrasound treatment at 20 °C, resulting in a remarkable improvement in emulsification. However, long-time ultrasonication led to an unstable state, causing the MCC solutions to show shear thinning behavior (pseudoplastic fluid). Compared with 50 °C temperature-controlled ultrasonication, ultrasonication at 20 °C had a greater influence on particle size, viscosity and hydrophobicity. These findings indicate that 20 °C TC-US could be a promising technology for the modification of MCC.

Highlights

Ultrasound (US) is one of the rapidly developing innovative and green techniques that offer great potential for implementation in the food industry
The size of the soluble particles exhibited a slight decreasing trend from 0 min up to 30 min under controlled temperature conditions. This result was in agreement with Shanmugam et al [25], who reported 20 kHz ultrasound at 41 W could slightly reduce the particle size of pasteurized homogenized skim milk [26]
These newly formed denatured/aggregated soluble whey proteins would interact with κ-caseins present on the surface of the casein micelles or form aggregates in the serum phase, further exhibiting an increase in particle size

Summary

Introduction

Ultrasound (US) is one of the rapidly developing innovative and green techniques that offer great potential for implementation in the food industry. Compared with other techniques (microwaves, gamma radiation), sound waves are generally considered safe, non-toxic, and environmentally friendly, making the use of ultrasound highly advantageous [1,2]. Compared with high-frequency ultrasound (20–100 kHz), low-frequency ultrasound (2–10 kHz) has found application in a wide range of dairy research applications, such as inactivation of microorganisms, extraction of components from cells or tissues, acceleration enzymatic activity, and dissolution of large particles [3,4,5,6]. A rich source of nutrients, can be fractionated into a wide range of components for use in food and beverages [7,8]. The current research on the effects of US on MCC is mainly focused on the modification of redissolved

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Results

Conclusion