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Freezing Efficiency and Quality Attributes as Affected by Voids in Plant Tissues During Ultrasound-Assisted Immersion Freezing

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Abstract

Voids, filled with air, in plant tissues, can attenuate ultrasound, resulting in weakening the effectiveness of ultrasound during immersion freezing. The effect of voids on ultrasound-assisted immersion freezing (UF) in selected plant tissues, apple, radish, and potato was investigated in the present study. The freezing time and quality attributes of firmness, drip loss, total calcium content, and total phenolic content were investigated in apple, radish, and potato samples treated by normal immersion freezing (IF) and UF. The results showed that the more the percentage voids in the plant tissues, the lower the effectiveness of the ultrasound treatment. The total freezing time reduction (%) due to UF was a power function of the volume of voids (%): y = 0.018x−1.057 (R2 = 0.994). Ultrasound at 0.62 W/cm2 (28 kHz) resulted in the best firmness and lowest drip loss in potato, while no significant (p > 0.05) differences in quality attributes were observed between IF and UF in apple samples. These findings indicated that UF was more effective in freezing fruit or vegetables with a highly dense structure.

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Funding

The authors are grateful to the National Key R&D Program of China (2017YFD0400404) for its support. This research was also supported by the Collaborative Innovation Major Special Projects of Guangzhou City (201604020057), the Agricultural Development and Rural Work of Guangdong Province (2017LM4173), the International and Hong Kong–Macau–Taiwan Collaborative Innovation Platform of Guangdong Province on Intelligent Food Quality Control and Process Technology & Equipment (2015KGJHZ001), the Guangdong Provincial R & D Centre for the Modern Agricultural Industry on Non-Destructive Detection and Intensive Processing of Agricultural Products, the Common Technical Innovation Team of Guangdong Province on Preservation and Logistics of Agricultural Products (2016LM2154), and the Innovation Centre of Guangdong Province for Modern Agricultural Science and Technology on Intelligent Sensing and Precision Control of Agricultural Product Qualities.

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Authors and Affiliations

  1. School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China

    Zhiwei Zhu, Zhubing Chen, Qianyun Zhou & Da-Wen Sun

  2. Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China

    Zhiwei Zhu, Zhubing Chen, Qianyun Zhou & Da-Wen Sun

  3. Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, China

    Zhiwei Zhu, Zhubing Chen, Qianyun Zhou & Da-Wen Sun

  4. Food Refrigeration and Computerized Food Technology (FRCFT), Agriculture and Food Science Centre, University College Dublin, National University of Ireland, Belfield, Dublin 4, Ireland

    Da-Wen Sun

  5. Shenzhen Dejieli Refrigeration Technology Co., Ltd., Gongming Street, Guangming District, Shenzhen, 518106, China

    Haiyang Chen

  6. Chengdu Rodbol Machinery Equipment Co., Ltd., Deyuan Town, Pidu District, Chengdu, 611730, China

    Yongjun Zhao

  7. Foshan Suk Precision Machinery Co., Ltd., Luocun Town, Nanhai District, Foshan, 528226, China

    Wenqing Zhou

  8. Guangzhou Yuelian Fisheries Refrigeration Engineering Co., Ltd., Daban Industrial Zone, Panyu District, Guangzhou, 511490, China

    Xianguang Li & Hongzhun Pan

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  1. Zhiwei Zhu
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  2. Zhubing Chen
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Correspondence to Da-Wen Sun.

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Zhu, Z., Chen, Z., Zhou, Q. et al. Freezing Efficiency and Quality Attributes as Affected by Voids in Plant Tissues During Ultrasound-Assisted Immersion Freezing. Food Bioprocess Technol 11, 1615–1626 (2018). https://doi.org/10.1007/s11947-018-2103-8

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