FOOD SCIENCE ›› 2017, Vol. 38 ›› Issue (23): 263-268.doi: 10.7506/spkx1002-6630-201723042

• Packaging & Storage • Previous Articles     Next Articles

Mechanism of Crispness Deterioration for Crispy Duck Product during Storage and Transportation

WANG Ru1, CHEN Jiwang1,2,*, HU Hai1, WANG Hongxun1, XIONG Youling L.1,2   

  1. 1. College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan 430023, China; 2. Hubei Collaborative Innovation Center for Processing of Agricultural Products, Wuhan 430023, China
  • Online:2017-12-15 Published:2017-12-07

Abstract: Crispy duck legs were stored at different constant temperatures (5 and 30 ℃) and relative humidities (50%, 70% and 90%) for 0, 2, 4, 6, 8 and 10 h, respectively. Meanwhile, moisture content, water activity, shear force, and microstructure of crispy duck legs were measured. The aims were to analyze the effect of moisture migration on the crispness of crispy duck legs during storage and transportation to investigate the underlying mechanism of crisp deterioration. The results showed that during storage at 5 ℃, a decrease of the moisture content in skin was firstly presented followed by an increase, tending to a constant value after 6 h. Water activity of skin increased to reach a plateau after 6 h. However, water activity of meat first decreased rapidly from 0 to 2 h and then slowly after 4 h. Shear force of skin increased from 0 to 6 h and then decreased quickly. During storage at 30 ℃, moisture content of skin increased at first and then decreased, and the changes in water activity and shear force were similar to those observed at 5 ℃. Moisture content and water activity of skin increased with an increase of relative humidity; at the same time, shear force increased and crispness decreased. Only a few big pores in skin were observed just after being fried, and the amount of pores with smaller diameter increased with the migration of moisture. The findings indicated that temperature and relative humidity significantly influenced moisture migration between skin and meat during storage and transportation of crispy duck. The slow moisture migration rate observed at 5 ℃ resulted in low moisture content and water activity in duck. Moisture content and water activity in duck skin increased with an increase of relative humidity. Furthermore, the microstructure of skin was destroyed due to the continuous moisture migration among skin, meat, and the environment, resulting in an increase of shear force and a decrease of crispness.

Key words: crispy duck leg, crispness, moisture migration, microstructure

CLC Number: