Abstract: This study explored the effects of freezing methods on water distribution and quality characteristics of fritters. The fritters were frozen by liquid nitrogen immersion freezing (LF), spiral tunnel freezing (SF) and refrigerator freezing (RF), respectively. The moisture content and T2 relaxation time of frozen fritters were measured, and the color, specific volume, texture and sensory quality of re-fried fritters were determined. The moisture content of fritters frozen by different methods was significantly different (P<0.05), and L* value, a*value and △E were highly significantly different (P<0.01).The content of bound water in LF- and SF-treated fritters’ pulp was significantly higher than that in RF treated fritters (P<0.01), while the content of free water was significantly lower (P<0.05). LF-treated fritters had the least water migration, and it also had the largest specific volume, the best crust color, tissue softness and porosity, as well as texture, which had the closest sensory quality to fresh fritters. Therefore, LF is expected to become a new freezing technology for industrial production of fritters, which provides a scientific reference for producing quick-frozen fritters.
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