CAJ | 학술논문

为研究松花蛋的涂膜保鲜，该文采用纳米SiO2和TiO2分别对聚偏二氯乙烯（polyvinylidene chloride，PVDC）和聚乙烯醇（polyvinyl alcohol，PVA）基蜂蜡石蜡复合涂膜材料进行功能改性并涂膜松花蛋，测定并分析贮藏过程中松花蛋质量损失率、含水率、菌落总数、质构和颜色等感官品质指标的变化，研究其对松花蛋的保鲜效果及感官品质的影响。结果表明：在温度22℃，相对湿度75%±2%条件下贮藏12周后，与未涂膜组相比，2种膜液均显著抑制水分的散失（P<0.05），纳米改性PVDC基复合膜使质量损失率降低29.9%，纳米改性PVA基复合材料使质量损失率降低32.1%；未涂膜组松花蛋的菌落总数为涂膜组的9～10倍；2种膜液均增强松花蛋的质构（降低硬度和咀嚼性，提高黏度），显著提高质地感官评分值（P<0.05），同时显著抑制 pH 值和游离碱度的降低（P<0.05）；涂膜组松花蛋的颜色较深，风味和滋味感官评价值较高（P<0.05），还原糖和游离氨基的含量较低（P<0.05），褐变强度较强且美拉德反应中间产物的量较多（P<0.05），表明不同复合涂膜材料可增强美拉德反应，促进风味物质的产生，研究结果为松花蛋涂膜保鲜技术的应用提供理论参考。
위연구송화단적도막보선，해문채용납미SiO2화TiO2분별대취편이록을희（polyvinylidene chloride，PVDC）화취을희순（polyvinyl alcohol，PVA）기봉사석사복합도막재료진행공능개성병도막송화단，측정병분석저장과정중송화단질량손실솔、함수솔、균락총수、질구화안색등감관품질지표적변화，연구기대송화단적보선효과급감관품질적영향。결과표명：재온도22℃，상대습도75%±2%조건하저장12주후，여미도막조상비，2충막액균현저억제수분적산실（P<0.05），납미개성PVDC기복합막사질량손실솔강저29.9%，납미개성PVA기복합재료사질량손실솔강저32.1%；미도막조송화단적균락총수위도막조적9～10배；2충막액균증강송화단적질구（강저경도화저작성，제고점도），현저제고질지감관평분치（P<0.05），동시현저억제 pH 치화유리감도적강저（P<0.05）；도막조송화단적안색교심，풍미화자미감관평개치교고（P<0.05），환원당화유리안기적함량교저（P<0.05），갈변강도교강차미랍덕반응중간산물적량교다（P<0.05），표명불동복합도막재료가증강미랍덕반응，촉진풍미물질적산생，연구결과위송화단도막보선기술적응용제공이론삼고。
Pickling is one of the oldest techniques in the food preservation as it not only extends the shelf life but also enhances the flavor and acceptability of the product. Pidan is a kind of traditional pickled egg with an extremely long shelf life. Its pleasant and fragrant taste is preferred by most of the people in China, Thailand and other Southeast Asian countries. Pidan is formed by the penetration of alkali through the egg shell and membrane, which leads to chemical changes and gelation of egg proteins. Apart from the formation of gel-like texture, alkaline treatment can induce the degradation of proteins as well as Maillard reaction to turn the color of pidan into brown during the processing. However, pickling could possibly destroy the outer shell membrane of eggs, make the shell structure loose and enlarge the pores of shell, which causes water to evaporate easily through the pores and the spoilage of fresh eggs. Therefore, coating pidan with composite film is one of the most effective ways to preserve the quality of pidan. Polyvinylidene chloride and polyvinyl alcohol are 2 kinds of macromolecular polymer with gas and water barrier performance, whose emulsions are used as based material to prepare nano-SiO2 and nano-TiO2 modified polyvinyl alcohol based composite coating material and nano-SiO2 and nano-TiO2 modified poly vinylidene chloride based composite coating material. In this paper, pidans were pickled by soaking chicken eggs into NaOH/NaCl/ZnSO4·7H2O solution for a period of time and then were divided randomly into 3 groups. Uncoated pidan was chosen as control group (CK). Secondary soaking coating method was adopted to coat pidan. The coating process was that put pidan into coating liquid for 1 min, then take pidan out and blow dry, and later the above-mentioned process was carried out again. Pidan coated with nano-SiO2 and nano-TiO2 modified poly vinylidene chloride based composite coating material (Group A) and nano-SiO2 and nano-TiO2 modified polyvinyl alcohol based composite film (Group B), and uncoated pidan (CK) were stored under the same preserved condition whose temperature was 25℃ and relative humidity was 75%±2%. During the storage the physical and chemical indicators included weight loss rate, albumen pH value, free alkalinity content, moisture, texture characteristics (hardness, cohesiveness, springiness, chewiness and gumminess), chromatic aberration, brown intensity, absorbance at 294 nm, reducing sugar content, free amino content, sensory evaluation, and total number of bacterial colony, which were detected every 2 or 3 weeks to determine the pidan quality. The results showed that physical and chemical indicators of pidan in each group significantly changed (P<0.05). Two kinds of coating materials both significantly reduced moisture loss and weight loss rate (P<0.05), retarded the change of pH value, free alkalinity content and textural properties (hardness, cohesiveness, springiness, chewiness and gumminess) of pidan, inhibited the growth of microorganisms, and improved the sensory evaluation of pidan. However,a* value, brown intensity, and absorbance at 294 nm of coated pidan were higher than uncoated pidan, andL* value,b* value, reducing sugar content and free amino content were less than uncoated group, which meant the development of brown color and the production of flavor substances were enhanced because of Maillard reaction. This paper provides the reference for the application of composite film materials in the preservation of pidan.