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利用酶与亲水胶体制备混浊西番莲汁的配料及其稳定性的研究

作　者: Mugwiza Telesphore
导　师: 钱和
学　校: 江南大学
专　业: Food Science and Technology
关键词: 西番莲酶解浑浊型果汁稳定剂浑浊型果汁稳定性
分类号: TS255.4
类　型: 硕士论文
年　份: 2010年
下　载: 53次
引　用: 0次
阅　读: 论文下载

内容摘要

百香果是一种鸡蛋状热带水果,又叫紫色西番莲。西番莲产于大部分热带、亚热带及少数温带地区。从西番莲中榨取的果汁营养丰富,对人体健康非常有益。由于西番莲有独特的强烈风味以及较高的酸度,西番莲的果汁被称为是一种天然的浓缩品。通过向西番莲果汁中加糖及稀释,可以使其成为美味的饮料,同时西番莲果汁还可以与其他的饮料进行调配,制作混合型饮料。目前,果汁生产已经成为了据有竞争性的行业,因此,西番莲果汁加工者需要改进果汁终产品的质量以适应市场的需求。本研究的目的是建立一种酶技术来加工混浊型果汁,同时应用胶体以确保果汁的稳定性。主要结论如下：首先对西番莲的一些物理化学特性进行了研究,结果表明新鲜西番莲的主要成分是碳水化合物,可溶性固形物含量为17.5°Brix, pH值为3.06,同时西番莲果肉还富含维生素,矿物质以及重要的氨基酸。本研究应用表面响应处理技术法(Response Surface Methodology RSM)优化西番莲果肉的酶液化条件。最佳条件为0.0136%w／w的Pectinex Ultra SP-L与0.0024%w／w的Amylase AG XXL,温度为49℃,pH为3.8,时间为25分钟。在该条件下,西番莲果肉中的果汁得率高达95.02%,与对照样品相比,当样品浊度为724 NTU,黏度为1.84cP时,果汁产率会提高23%；当样品的浊度黏度为0.56cP时,果汁产率会下降31.63%。通过对一些影响因素的优化,可以使最终的果汁呈现出较佳的浑浊度以及稳定的色泽。本实验还对胶体如瓜尔豆胶、黄原胶、结冷胶、羧甲基纤维素钠、结冷胶与黄原胶的混合物对果汁的色泽、黏度、浊度影响进行了研究。每个样品均在室温下储存30天,同时向样品中添加不同浓度的胶体,结果显示胶体可以减缓果汁的沉淀,但并不是每种胶体都可以维持果汁稳定的胶状体系。经肉眼观察果汁的色泽及浑浊度表明0.10%w／w黄原胶单独使用,或者0.010%w／w结冷胶与0.06%w／w黄原胶混合使用可以能将浑浊型果汁稳定在令人满意的水平。最后,感官评定表明,与0.06%w／w黄原胶相比较,应用0.010%w／w结冷胶与0.06%w／w的黄原胶混合物可以更容易被感光评定成员所接受。

全文目录

ACKOWLEDGEMENTS  5-6
ABSTRACT  6-8
摘要  8-10
TABLE OF CONTENTS  10-14
LIST OF TABLES  14-16
LISTE OF FIGURES  16-17
ABBREVIATIONS  17-18
PART 1. INTRODUCTION  18-32
  1.1. HISTORICAL BACK GROUND  18-21
  1.2. PASSION FRUIT DISTRIBUTION IN CHINA  21-22
  1.3. PASSION FRUIT MORPHOLOGY  22-23
  1.4. PASSION FRUIT COMPOSITION  23-24
  1.5. PASSION FRUIT USES  24-26
    1.5.1. Food uses  24-25
    1.5.2. Medicinal uses  25
    1.5.3. Other uses  25-26
  1.6. PASSION FRUIT PROCESSING  26-30
    1.6.1. Juice extraction  26-28
    1.6.2. Cloudy juice processing  28-29
    1.6.3. Stability of fruit juice  29-30
  1.7. CURRENT PROBLEM IN PROCESSING OF CLOUDY JUICE  30-31
  1.8. RESEARCH OBJECTIVES  31
  1.9. HYPOTHESIS OF THE STUDY  31-32
PART 2:MATERIALS AND METHODS  32-44
  2.1. MATERIALS  32
    2.1.1. Raw material and chemicals  32
    2.1.2. Enzymes  32
  2.2. METHODS  32-44
    2.2.1. Juice extraction process  32
    2.2.2. Enzymatic treatment  32-33
    2.2.3. Juice yield  33
    2.2.4. Viscosity  33
    2.2.5. pH  33
    2.2.6. Turbidity  33
    2.2.7. Cloudiness  33-34
    2.2.8. Moisture content  34
    2.2.9. Total soluble solids  34
    2.2.10. Protein content  34
    2.2.11. Ash content  34-35
    2.2.12. Iodimetric determination of Ascorbic acid (vitamin C)  35
    2.2.13. Vitamins  35
    2.2.14. Mineral content  35
    2.2.15. Flavor compounds  35-36
    2.2.16. Amino Acids content  36
    2.2.17. Pectin and starch analysis  36
    2.2.18. Total and reducing sugars  36-37
    2.2.19. Titratable acidity  37
    2.2.20. Total soluble phenolic compound  37
    2.2.21. β carotene  37-38
    2.2.22. Color  38
    2.2.23. Particle size analysis  38
    2.2.24. Cloudy passion fruit juice production  38-39
    2.2.25. Stabilization of the cloudy passion fruit juice  39-40
    2.2.26. Microbiological analysis  40-41
      2.2.26.1. Determination of total plate count (TPC)  40-41
      2.2.26.2. Determination of yeast and mold  41
    2.2.27. Sensory evaluation  41
    2.2.28. Experimental design and statistical analysis  41-44
PART 3:RESULTS AND DISCUSSION  44-77
  3.1. The main composition of passion fruit pulp  44-46
  3.2. Main flavor components of fresh passion fruit pulp  46-48
  3.3. Amino acid composition of passion fruit pulp  48-49
  3.4. Processing technology of cloudy passion fruit juice and influence of variable conditions on selected quality parameters  49-62
    3.4.1. Determination of enzymatic hydrolysis parameters range  50-53
    3.4.2. Response measurement  53-62
      3.4.2.1. Juice yield, turbidity and viscosity  55
      3.4.2.2. Statistical analysis  55-56
      3.4.2.3. Effect of enzyme concentration, temperature, pH and time on yield #39 turbidity and viscosity of passion fruit juice  56-61
      3.4.2.4. Optimization  61-62
  3.5. Processing technology of cloudy passion fruit juice and its #45 behavior during the storage  62-68
    3.5.1. Composition of cloudy passion fruit juice  62-63
    3.5.2. Amino acid composition of cloudy passion fruit juice  63-64
    3.5.3. Flavor components of cloudy passion fruit juice  64-66
    3.5.4. Particle size distribution of the cloudy passion fruit juice  66-67
    3.5.5. Effect of sterilization on color  67-68
    3.5.6. Color preservation of cloudy passion fruit juice during #51 Sterilization  68
  3.6. Effect of storage conditions on certain components and #51 quality parameters of cloudy passion fruit juice  68-72
    3.6.1. Ascorbic acid, sugars evolution and color change of #51 cloudy passion fruit juice  68-70
    3.6.2. Amino acids evolution of cloudy passion fruit juice during storage  70-72
  3.7. Stabilization of cloudy passion fruit juice using different #55 Hydrocolloids  72-74
  3.8. Microbiological analysis  74-76
  3.9. Sensory evaluation  76-77
GENERAL CONCLUSION AND RECOMMENDATION  77-79
  GENERAL CONCLUSION  77-78
  RECOMMENDATION  78-79
REFERENCES  79-85
PAPERS PUBLISHED  85-86
ANNEXES  86-93

利用酶与亲水胶体制备混浊西番莲汁的配料及其稳定性的研究

内容摘要

全文目录

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