【作者】 陈磊；

【导师】 王燕；

【作者基本信息】 湖南农业大学 ， 农业推广， 2010， 硕士

【摘要】 作为苹果生产加工大国,我国每年都会有180多万t苹果渣产生,除少部分经粗加工用作饲料外,大部分作为废弃物丢弃而导致严重的资源浪费和环境污染。苹果渣具有成本低、营养丰富、毒害物质含量低等特点,经深加工后可提高附加产值,减轻环境污染,提高企业经济效益,具有很大的发展潜力。本研究以当前苹果渣的研究现状及目前世界关于提取生物蜡、果胶、膳食纤维的技术为出发点,对苹果蜡进行提取得出最佳萃取工艺条件,并对其进行理化分析；将提取苹果蜡后的苹果渣进一步用于提取果胶,分析影响因素并优化提取工艺；最后将提取果胶后的苹果残渣进一步用于提取水不溶性膳食纤维,达到对苹果渣综合利用的目的。主要研究结果如下：1.用不同有机溶剂从苹果渣中提取苹果粗蜡,氯仿、石油醚、苯和正己烷的提取率分别为：3.58%、3.04%、2.47%和2.35%；氯仿提取物颜色较深,呈棕黄色。氯仿提取苹果粗蜡的优化工艺：质液比1：30,抽提4h后,苹果粗蜡的提取率可达3.63%,用异丙醇和丙酮精制苹果粗蜡后得到淡黄色半固态精制苹果蜡。经测定：苹果蜡的熔点为62.8—64.8℃；苹果蜡的酸价、皂化价及碘价分别为13.3mg KOH/g蜡、82.8mg KOH/g蜡、10.7g I2/100g蜡。2.首先采用果胶酸钙法测得苹果渣中果胶的含量为5.89%,然后采用超声波辅助酸水解法提取果胶,分析溶液pH值、超声时间、温度及料液比对果胶提取率的影响,得到最优的工艺条件为：A2B2C3D1,即pH为2.5,反应温度为80℃,料液比为1：25,超声时间为30min,在此条件下果胶的提取率可达到88.4%。合并所有反应得到的果胶粗提取物经70%乙醇洗涤数遍后低温干燥得到黄色的果胶产品。分析了乙醇浓度、pH值、时间对粗果胶分离的影响,得到醇析分离沉淀果胶的最佳条件是：乙醇终浓度60%,果胶提取液pH值2.0,温度4℃,静置时间4h,此条件下果胶沉析率为91.02%。3.采用中性洗涤法测定经提取果蜡和果胶后的苹果残渣含水不溶性膳食纤维为27.625%,采用超声波辅助碱法制备苹果渣水不溶性膳食纤维,分析了料液比、碱液浓度、抽提时间及温度对水不溶性膳食纤维产量的影响,得出碱提法提取水不溶性膳食纤维的最佳工艺为：A2 B3 C1 D2,即料液比为1：12,碱浓度为0.6mol/L,反应温度为35℃,超声时间为60min,在此条件下IDF得率可达到26.47%。合并所有反应得到的水不溶性膳食纤维得到乳白色产品,并测得在最佳工艺得到的水不溶性膳食纤维的持水性为95.085%,溶胀性为7.105%。更多还原

【Abstract】 As a large country of apple production and processing, China produce more than 180 million tons of apple pomace annually. Little of the apple pomace was used as animal feed, while most been wasted, causing serious resources waste and pollution. Low cost, nutrition richness, free from toxic or harmful substance is the characteristic of apple pomace. After processing, the additional value raised, enterprise’s economic benefits raised, pollution reduced, apple pomace deep-processing has great development potential. Based on the current research on apple pomace processing and the extraction technology of biological wax, pectin and dietary fiber, we study the extraction of apple wax and analysised its physical and chemical character. After extaction of apple wax, apple pomace is used for the extraction of apple pectin. Factors affecting the extraction of apple pectin was analysized and got the optimized extraction technology. The residue was further used for water-insolvable dietary fiber extraction. Main research results are follown as follows:1.Extract apple wax with different organic solvent (chloroform, petroleum ether, benzene, n-hexane) from apple pomace, the extraction ratio were 2.47%,3.58%, 3.04% and 2.35%,respectively. Substance extratacted with chloroform was tan-yellow. The extraction ratio reached 3.63% under optimized condition: mass-liquid ratio 1:30 for 4 hour. Refine crude wax with isopropyl and acetone, we got semi-solid, light-yellow refined apples wax. The melting point of wax apple is: 62.8-64.8℃;acid value, saponification value and iodine value were 13.3 mg KOH/g wax,82.8g KOH 82.8/g wax,10.7 g I2/g wax, respectively.2. Firstly, use calcium pectinate measure to detect the content of apple pectin (yield was 5.89%), then extract with ultrasonic auxiliary acid hydrolysis method. Analyzed pH value, ultrasonic time, temperature and mass-liquid ratio to the extraction of pectin. The optimum extraction conditions is:A2B2C3D1, namely, pH 2.5,temperature 80℃, mass-liquid ratio 1:25 for 30min, the yield of pectin is 88.4%. Merge all the crude pectin and refine it by 70% ethanol for several times,we got yellow products. Analyze the ethanol concentration, pH value, time to the precipitation of crude pectin, the best conditions for pectin precipitation was:ethanol concentration 60%, pH 2.0, 4℃for 4 h, the extraction ratio is 91.02% under such condition.3.Adopt neutual washing method for the determination of water-insolvable dietary fiber (yield was 27.625%). Use ultrasonic auxiliary alkali extration method for the extraction of water-insoluble dietary fiber from apple residue. Analyze the mass-liquid ratio, alkali concentration, temperature and time to extraction of water-insoluble dietary fiber, and we got the optimum condition:A2B3C1D2, namely mass-liquid ratio 1:12,alkali concentration 0.6 mol/L,35℃for 60min, the water-insoluble dietary fiber ratio reached 26.47% under such conditions. The water-insoluble dietary fiber was milky white, and the water binding capacity of the water-insoluble dietary fiber was 95.085%, and swelling capicity was 7.105%.更多还原