Abstract: In order to shorten the production period of preserved egg, intermittent pressurization was used to develop a rapid curing device. In the curing tank, pressurized and depressurized was under the control of a pressure control program. The permeation of alkali from the curing solution into eggs was accelerated at high pressure. Conversely, when the pressure inside eggs was lower than that outside eggs at low pressure, the leakage of water, H2S, NH3 and CO2 generated in eggs was accelerated, thereby being beneficial to further permeation of alkali into eggs and accelerating the ripening of preserved eggs. Based on a comprehensive evaluation of free alkalinity in egg white and yolk, the hardening rate of egg yolk and sensory characteristics, the optimum curing conditions were determined as follows: the optimal alkali concentration was 5%, the high pressure 180 kPa and the low pressure were held for 40 min and 12 min, respectively, and the curing time was 206 h. By using the process, the production period could be shortened by up to 22% as compared with the traditional process. Thus, the production efficiency was considerably increased. All curing time, low pressure holding time, high pressure holding time, alkali concentration and high pressure level had a significant effect on the quality of preserved egg (P＜0.05). The process parameters could be ranked in decreasing order of their importance as follows: curing time, low pressure holding time, high pressure holding time, alkali concentration and high pressure level. Among them, low pressure holding time was the most important factor affecting free alkalinity in inner egg yolk.

Key words: duck eggs, intermittent pressurization, production cycle, quality