Novel hybrid strategy for improving product quality of freeze-dried dumplings: different cooking methods combined with chitosan coating

Abstract

To improve the quality of freeze-dried dumplings, a novel hybrid strategy that different cooking methods combined with chitosan coating were applied in the preparation of dumplings. The dumplings, obtained according to the formula, first treated by three different cooking methods (microwave, boiling, and steaming), respectively, and then coated with chitosan with a mass fraction of 1.5%. The dumplings without coating treatment was used as control group. Results showed that, the drying time of steamed dumplings was the shortest (720 min), but its whiteness and rehydration performance were unacceptable to consumers. The whiteness of boiled dumplings was the highest, but its drying time was 90 min longer than that of steamed dumplings. The freeze-dried dumplings pretreated by microwave cooking had the best rehydration performance (rehydration rate, cracking rate of rehydrated dumplings, and rehydration loss rate) and hardness. Chitosan coating treatment of cooked dumplings was been found to have a satisfactory positive effect on inhibiting the cracking rate of freeze-dried dumplings, the cracking rate of rehydrated dumplings and the rehydration loss rate of freeze-dried dumplings. Microwave cooking combined with chitosan coating was considered to be the most suitable hybrid strategy for the production of high-quality freeze-dried dumplings.

Keywords:

• Dumplings
• freeze-drying
• microwave cooking
• chitosan coating
• product quality

Acknowledgment

We acknowledge the financial supports from the China Key Research Program (Contract No. 2017YFD0400501), Postgraduate Research & Practice Innovation Program of Jiangsu Province (No. KYCX20_1844), Jiangsu Province Key Laboratory Project of Advanced Food Manufacturing Equipment and Technology (No. FMZ202003), all of which enabled us to carry out this study.

Disclosure of interest statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.