盐水浸泡腌制过程中鸭蛋壳裂的成因

Study on the Causes of Duck Egg Shell Cracking During Brine Curing Process

研究了用盐水浸泡法腌制过程中,鸭蛋盐分含量、蛋重、蛋壳比重、蛋壳厚度、气孔数、气室直径、单位面积蛋壳脆性、强度和蛋壳截面微观结构的变化。结果表明,5周内,随着盐分含量的增加,鸭蛋重从61.85 g增加至63.16 g;蛋壳比重、蛋壳厚度均无明显变化,气室直径稍有变化;气孔数从24.93个/0.25 cm2减少至10.40个/0.25 cm2;蛋壳脆性和强度分别从445.2N和1461.2N降至240.6N和446.1N;蛋壳强度从44.504 N降至34.452 N。鸭蛋蛋壳比重低于10%、蛋壳厚度低于0.355 mm、蛋形指数在1.380～1.460低强度范围内腌制期间易裂壳。腌制5周后,蛋壳截面纹路多、有不规则断层;裂壳蛋的壳截面显粗糙、有不规则断裂,乳突排列不均,壳膜结构松散。鸭蛋壳裂的产生是由新鲜鸭蛋壳质量决定,盐水腌制破坏了蛋壳的微观结构和脆性、强度,并对壳裂起到了促进作用。

During the duck egg brine immersing process, changes in salt content, egg weight, eggshell relative weight, eggshell thickness, pore shell cross-section microstructure number, chamber diameter, eggshell were studied. On the 5th weeks after fragility and hardness per unit area and eggsalting, with the salt content increasing, the duck weight increased from 61.85g to 63.16g; eggshell weight, eggshell thickness had no significant changes; a slight change in chamber diameter; pore number was reduced from 24.93/0.25cm2 to 10.40/0.25cm2. Eggshell fra- gility and hardness per unit area was reduced from 445.2N and 1461.2N to 240.6N and 446.1N respectively. Egg force decreased from 4. 538kgf to 3. 513kgf. Duck eggshell relative weight was less than 10%. Eggshell thickness was less than 0. 355mm. Egg shape index was between 1. 380 and 1. 460 which was in the low intensity range. The egg- shell were very easily to crack. After 5th weeks of salting, there were some lines and irregular fault on eggshell cross- section. Cracked egg shell had rough cross-section with some irregular fracture, papillae arrangement was uneven, eggshell membrane was loosen. The conclusion is that duck eggshell crack is caused by quality of fresh duck eggshell, and the brine curing processing destroyed the shell microstructure and fragility, and hardnes.