【作者】 李春莉；

【导师】 郑为完；

【作者基本信息】 南昌大学 ， 粮食、油脂及植物蛋白工程， 2008， 硕士

【摘要】 本论文主要研究了以麦芽糊精和代可可脂为原料制备耐酸型微胶囊粉末油脂的配方和工艺,并检验了耐酸型微胶囊粉末油脂的品质,同时研究了其在酸性果汁饮料中的应用,具体研究结果如下:1.建立了耐酸型微胶囊粉末油脂的乳化体系。在众多乳化剂中,通过筛选实验确定了变性淀粉55-1479和阿拉伯胶复配作为耐酸型微胶囊粉末油脂的乳化剂,包埋效果最好。通过单因素实验确定了两种乳化剂的配比和用量。采用喷雾干燥法制备的结果表明,其复配比例为2:1,用量分别为10%和5%时,微胶囊产品包埋率最高。优化了产品的微胶囊化工艺。实验采用二相乳化法,乳化温度70～75℃,均质压力30MPa,均质2次;喷雾干燥小试工艺参数为:进风温度185℃,出风温度95℃,进料量为22.0mL·min^-1,气流压力0.10Mpa。2.检验了耐酸型微胶囊粉末油脂的品质。结果表明:产品表面油含量低（1.05%）、包埋率高（96.5%）,水分含量在2.5%以下,密度在0.5g·cm^-3以下,溶解性能良好,粉末细腻,颗粒分布均匀,颜色为乳白色,气味纯正,无异味。各项理化指标均符合微胶囊质量指标,冲泡时复原乳状液均匀,无表面油、无粒子挂壁现象,放置24h后复原乳状液仍保持稳定。微胶囊产品包埋率及复原乳状液的粒度分布情况在180天的储存期内基本没有变化,产品微胶囊化效果好,乳化稳定性高。测定在180天的储存期内耐酸型微胶囊产品及其原料油的过氧化值和酸价变化。实验表明:代可可脂在考察的180天时间内,过氧化值经历了上升到下降的过程,发生了酸败;而耐酸型微胶囊粉末油脂在考察的180天时间内,过氧化值变化很小,仅有微弱上升;代可可脂的酸价在考察的180天时间内上升了19.73个单位,而微胶囊产品酸价只上升了4.82个单位。说明所研制的微胶囊成膜材料性能好,能有效的保护芯材,阻止其与空气中的氧气、水等接触,产品耐贮藏,保质期长。检验了制备的粉末油脂的耐酸性,经盐酸（无机酸）、柠檬酸（有机酸）、抗坏血酸（还原性物质）试验,研制的粉末油脂耐酸性能优越,可以满足在酸性饮料的应用。3.研究了耐酸型微胶囊粉末油脂在酸性饮料中的应用。将耐酸型微胶囊粉末油脂添加到果汁饮料中,调配出一款酸性仿乳果汁饮料。其中果汁类型选用苹果汁,添加量为50%,酸味剂为配比为乳酸:柠檬酸:苹果酸（W/W）=5:4:1的混合酸,添加量为0.3%,粉末油脂的添加量为10%,蔗糖添加量为8%。各感官指标均达到要求。测定自制酸性仿乳果汁饮料的沉淀率及其随时间的变化,发现其沉淀率变化不大,说明此饮料的稳定性好。更多还原

【Abstract】 The formula and process of acidproof powdered oil prepared by using maltodextrin and cocoa butter substitute as raw materials were investigated in this paper. Also, the microcapsule quality was tested and its application in acidic jucie beverage was studied. The main results were as follows:1. The emulsification system of acidproof powdered oil was established. Among many varieties of emulsifiers, it was determined by experiments that the microencapsulation effect was best with modified starch 55-1479 and arabic gum as emulsifier of acidproof powdered oil. The proportion and quantity of two kinds of emulsifiers were decided by single factor experiment. It was showed that the microencapsulation effieiency of product prepared by spray drying technique was highest when the emulsifier proportion was 2:1 and the additions were repectively 10% and 5%.The microencapsulation process was optimized. Applying two phase emulsification techinique, the temperature of emulsification was 70-75℃, homogenizing pressure was 30Mpa and homogenizing twice. The optimum technological conditions of spray drying were as follows: inlet air temperature 185℃, outlet air temperature 95℃, feeding rate 22.0mL·min^-1, air pressure 0.10Mpa.2. The microcapsule quality was tested. The results showed that: the oil amount on the surface was low （1.05%）, but the product had a high rate of embedded （96.5 percent）, moisture content of powdered oil was under 2.5%, the powder was exquisite and uniform, its color was ivory, the smell was pure with no peculiar smell. All physical and chemical indexes were qualified to the quality standard of microcapsule. The recovery emulsion was uniform with no surface oil and practicles linking to the wall. After standing for 24 hours, it remained stable. The microencapsulation efficieny and particle size distribution of recovery emulsion varied little during 180 days storage time, the microencapsulation effect was good and emulsion stability was high. The investigation on the changes of peroxide value and acid value of microcapsule product and cocoa butter substitute claimed that: the peroxide value of cocoa butter substitute in the 180 days first rose then dropped and rancidity had happened; however, that of acid proof microcapsule powdered oil just had little rise during those days. The acid value of cocoa butter substitute rose 19.73 units and the microcapsule product only rose 4.82 units. It was indicated that because the property of microcapsules’ film material was so good that it could protect the core material effectively from contacting with the oxygen, water and others in the air, the prepared microcapsule had a long shelf life.The acid resistance of prepared powdered oil was inspected. According to the results of hydrochloric acid（inorganic acid）, citric acid（organic acid） and antiscorbic acid（reducibility material） test, it was known that the properties of prepared powdered oil were excellent, which could satisfy the application in acidic drinks.3. The application of acid proof powdered oil in acidic beverage was investaged. Powdered oil was added to juice drink, then a kind of acidic milk-like juice beverage was produced. Apple juice was selected as juice type, its addition was 50%, acidity agent was complexed lactic acid, citric acid and malic acid, the proportion was 5:4:1, and the addition was 0.3%; the addition of powdered oil and sucrose was respectively 10% and 8%. Each sensory index meeted the certain requirements.The precipitation rate and its variations with time were determined. It was discovered that the precipitation rate changed little, which showed that the stability of the drink was good.更多还原