Partmann W, Wedler A
Z Ernahrungswiss. 1979 Sep;18(3):191-208. doi: 10.1007/BF02020600.
Only a few and contradictory results are available on the storage stability of hard boiled eggs which are of considerable importance for institutional feeding. Therefore four storage experiments on about 500 hard boiled eggs each were carried out and chemical and sensorial changes occurring during storage investigated. The one-day-old eggs of the same origin were boiled for 17 minutes under standard conditions and subsequently stored in air at a relative humidity between 73 and 85% at 4 degrees C (experiment No. 1), at 20 degrees C (experiments No. 2 and 3) and in pure carbon dioxide at 20 degrees C (experiment No. 4). Immediately after boiling, the eggs used for experiments No. 3 were dipped into coloured resin for egg shells (natural Manila-Kopa; dissolved in ethanol and stained with "Acillantechtgrün). Losses in weight during storages were distincly lower in the lacquered eggs than in the non-lacquered samples otherwise treated in the same manner. The weight decrease caused by the loss of water was extraordinarily high in pure CO2 and is due mainly the the decrease of the pH in the egg whites caused by the uptake of CO2. A few days after boiling the concentration of the free amino acids reached approximately the same level in albumen and yolk and remained practically constant over the following 3 weeks. For the breakdown of lecithine in yolk determined according to Grossfeld and Peter, a "deterioration quotient" of 6, like in unboiled eggs, was fixed as the limit value for unspoiled condition. Accordingly a possible storage time of 3 to 4 weeks resulted for the eggs stored at 4 degrees C and for the eggs treated with stained resin. The non-lacquered eggs stored in air or in CO2 at 20 degrees C reached the critical value in about 10 days. From the vitamins A, B1 and B2 only vitamin A showed considerable losses during storage. On the basis of the microbiological (3) and chemical findings and of the sensorial evaluation of colour, consistency, odour and taste of egg whites and yolks, the following storage times were determined for eggs in the quality class "saleable" requiring an overall rating not lower than 6 (satisfactory): 14 to 16 days, for non-lacquered eggs stored at 4 degrees C and for lacquered eggs at 20 degrees C whereas 5 days were found to be the maximum storage time for untreated eggs stored at 20 degrees C. If boiled eggs are stored in pure carbon dioxide at 20 degrees C, a distinct quality loss is observed already after a few days.
对于机构供餐而言至关重要的煮鸡蛋的储存稳定性，目前仅有一些相互矛盾的结果。因此，进行了四项储存实验，每项实验约有500个煮鸡蛋，并对储存期间发生的化学和感官变化进行了研究。将同一天产的、来源相同的鸡蛋在标准条件下煮17分钟，随后分别在4℃（实验1）、20℃（实验2和3）的空气中以及20℃的纯二氧化碳中（实验4）储存，相对湿度保持在73%至85%。实验3所用的鸡蛋在煮后立即浸入用于蛋壳的彩色树脂中（天然马尼拉-科帕；溶解于乙醇并用“Acillantechtgrün”染色）。在相同处理方式下，涂漆鸡蛋在储存期间的重量损失明显低于未涂漆的样品。在纯二氧化碳环境中，因水分流失导致的重量下降非常高，这主要是由于蛋清中pH值因二氧化碳的吸收而降低所致。煮后几天，蛋清和蛋黄中游离氨基酸的浓度达到大致相同水平，并在接下来的3周内基本保持不变。对于根据格罗斯费尔德和彼得的方法测定的蛋黄中卵磷脂的分解情况，将“变质系数”为6（与未煮鸡蛋相同）确定为未变质状态的极限值。据此，在4℃储存的鸡蛋以及用染色树脂处理的鸡蛋可能的储存时间为3至4周。在20℃空气中或二氧化碳中储存的未涂漆鸡蛋在大约10天内达到临界值。在维生素A、B1和B2中，只有维生素A在储存期间有相当大的损失。根据微生物学（3）和化学研究结果以及对蛋清和蛋黄的颜色、稠度、气味和味道的感官评估，对于质量等级为“可销售”（总体评分不低于6分，即满意）的鸡蛋，确定了以下储存时间：在4℃储存的未涂漆鸡蛋和在20℃储存的涂漆鸡蛋为14至16天，而在20℃储存的未处理鸡蛋的最长储存时间为5天。如果煮鸡蛋在20℃的纯二氧化碳中储存，几天后就会观察到明显的质量损失。
