【作者】 刘会珍；

【导师】 高振江；

【作者基本信息】 中国农业大学 ， 种植业， 2005， 硕士

【摘要】 该文以产后12小时的鲜鸡蛋为试材,以不同保鲜工艺的选择为主要研究过程,分析了常温条件(25℃,相对湿度60～80%)贮藏鸡蛋品质指标的变化情况,并研究了涂膜处理对不同蛋龄鸡蛋品质变化的影响,以期为鸡蛋保鲜工作提供理论和技术依据。 鸡蛋在常温条件贮藏,其品质指标变化分为4个等级:鲜蛋、次鲜蛋、陈旧蛋和散黄蛋,贮存6天,品质由鲜蛋降为次鲜蛋,15天品质趋于陈旧蛋,25天出现散黄蛋,30大散黄率达60%以上。鸡蛋常温贮存的保鲜期为6天左右。 5种消毒方法对蛋壳表面细菌的杀菌效果差异显著(P<0.05),优劣次序为:开水浸烫>甲醛熏蒸>过氧乙酸熏蒸>高锰酸钾浸泡>过氧乙酸浸泡:只有开水浸烫法具有保鲜作刚,适宜实际应用的消毒方法为过氧乙酸熏蒸和甲醛熏蒸。 3种不同性质的保鲜剂处理鸡蛋,保鲜效果差异极显著(P<0.01),优劣次序为:液体石蜡>聚乙烯醇>壳聚糖。常温条件贮存30天,壳聚糖处理组次鲜蛋率100%;聚乙烯醇处理组鲜蛋占50%,次鲜蛋占50%:液体石蜡处理组鲜蛋率100%。 通过对比不同保鲜工艺对鸡蛋品质指标的影响,得出最优保鲜工艺为液体石蜡直接涂膜,该组鸡蛋在常温条件贮藏30天,其品质相当于对照组贮藏6天的鸡蛋品质,失重率为0.73%。相对密度为1.067,蛋黄系数为0.37,蛋白系数为0.71,蛋白pH值为8.01。 研究了涂膜保鲜对不同蛋龄鸡蛋品质指标的影响,结果表明:蛋龄越短,鸡蛋越新鲜,贮藏过程中品质指标变化越缓慢,贮藏后的效果也越好,涂膜保鲜的最佳蛋龄为0～3天。更多还原

【Abstract】 Fresh eggs layed within 12 hours were selected as materials. A series of experiments were conducted toresearch the change of fresh indexes. Choice of different preservation technics was the central contentof this paper. Effects of preservation with film on different age of eggs were analyzed.Exterior and interior quality of eggs were studied at normal temperature. The results showed that freshegg become hypo-fresh after 6-day storage at 25℃ and 60%~80% of relative humidity, banality eggsafter 15-day storage, dispelling yolk eggs after 25-day storage, the rate of dispelling was exceeding 60%after 30-day storage.Disinfected shell eggs with peroxid acetic acid, formaldehyde, potassium permanganate and boilingwater. Effects of sanitizing were significantly different (P<0.05) .Dipping eggs in boiling water was thebest, suffocating was better, dipping was the worst. When eggs were stored for 20 days, the method withboiling water prevented egg quality descending ,but others couldn’t. The best sanitizing methods weresuffocating with peroxide acetic acid and formaldehyde.Effects of three preservation agents were significantly different (P<0.05) . The chitosan-treated eggswas the worst with 100% hypo-freshness; followed by polyvinyl alcohol with 50% freshness and 50%hypo-freshness ; the paraffin-treated eggs had almost the freshness of 100% after 30-day storage. It wasfound that the characters of agents were determined effect of fresh-keeping.Eggs were sanitized with peroxid acetic acid, coated with three different agents . The results showedthat the best preservation technics was coated with liquid paraffin. The paraffin-treated eggs had almostthe freshness of 100%, with only weight losing rate 0.73%, relatively density 1.067, yolk coeffient 0.37,albumen coeffient 0.71, the value of pH 8.01 after 30-day storage, equal to the control freshness only for6 days under the same conditions.Adopting eggs of 0-day, 3-day, 6-day, and 10-day, after coated with paraffine, it was found that theshorter eggs age was, the fresher eggs was, the more slowly egg quality descended, the better effect offresh-keeping was. The best egg age of preservation was 0~3 days.更多还原