The Water Properties of Forzen Dough at Low Temperature Determined by NMR

The water properties of frozen dough were measured by NMR over the temperature range from -70℃ to 5℃.The thawing process of dough was also studied by MRI.The water in dough can be divided into two portions ,that are the half-bound water, the T2 of which is ≈ 10ms, and the deep-bound water, the T2 of...

Full description

Saved in:
Bibliographic Details
Main Authors: Wu Youzhi, Liu Baolin
Format: Article
Language:zho
Published: Journal of Refrigeration Magazines Agency Co., Ltd. 2013-01-01
Series:Zhileng xuebao
Subjects:
Online Access:http://www.zhilengxuebao.com/thesisDetails#10.3969/j.issn.0253-4339.2013.01.097
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The water properties of frozen dough were measured by NMR over the temperature range from -70℃ to 5℃.The thawing process of dough was also studied by MRI.The water in dough can be divided into two portions ,that are the half-bound water, the T2 of which is ≈ 10ms, and the deep-bound water, the T2 of which is ≈ 2ms. During freezing,the half-bound water partly form to ice and the other change to unfreezale water. The deep-bound water did not change or move. So improving the ratio of deep-bound water in dough is benefit to frozen dough production and inhibiting ice crystals generating. According different NMR data, it is confirmed that the glass transition of dough occurs at -30℃ and the ice melting at -9℃. The water in frozen dough can be classified into three parts and they are the solid ice (29.71%), the real unfreezable water (22.2%), the deep-bound water (33.81%).
ISSN:0253-4339