11103

850 دكتري

دكتري

علوم و صنايع غذايي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1394

نه، 81ص.: مصور

جواد كرامت

ناصر همدمي، محمد حجت الاسلامي

علي نصيرپور، عبدالرضا حاجي پور، محسن لبافي مزرعه شاهي

1395/01/15

مهندسي كشاورزي

ID850 دكتري

چكيده 4 فصل اول مقدمه و بررسي منابع 2 4 4 مقدمه 2 4 2 نگاهي اجمالي به مراحل فرايند توليد قند و شكر از چغندرقند 9 4 2 4 استخراج قند از خالل ديفوزيون 1 4 2 2 تصفيه شربت خام 1 4 2 9 اهداف تصفيه 5 4 2 1 تهيه شيرآهك و گازكربنيك 6 4 2 5 افزودن شيرآهك به شربت يا دفكاسيون 6 4 2 6 افزودن گازكربنيك به شربت 6 4 2 7 صاف كردن 6 4 2 8 سولفيتاسيون 7 4 2 3 تغليظ شربت اواپراسيون و كريستاليزاسيون 7 4 9 تركيبات شربت چغندرقند 8 4 1 ناخالصيهاي غير قندي شربت چغندرقند 8

1Evaluation of Colorants and Color Precursors during Sugar Beet JuiceProcessing in Model Systems Using Gel Permeation Chromatography Saadi Gharib Bibalan s gharib@ag iut ac ir January 2015 Department of Food Science and Technology College of Agriculture Isfahan University of Technology Isfahan 84156 83111 IranDegree PhD Language FarsiJavad Keramat keramat@cc iut ac irNasser Hamdami Hamdami@cc iut ac irMohammad Hojjatoleslamy mohojjat@gmail comDepartment Graduate Program coordinator Mohammad Mahdi Majidi Department of Food Science and Technology College of Agriculture Isfahan University ofTechnology Isfahan 84156 83111 Iran Board Member of Kavosh Agriculture and Sugar Research Center Isfahan Iran Department of FoodScience and Technology College of Agriculture Islamic Azad University Shahre kord Branch ShahreKord Iran AbstractIn the first part of this study the degradation of two color precursors tyrosine and ferulicacid as the most and the lowest color precursors present in raw sugar beet juice respectively in different kind of model systems sucrose solution and raw sugar beetjuice via Fenton process was investigated in lab scale and industrial conditions Centralcomposite design and response surface methodology RSM were used to evaluate therelationships between degradation of the color precursors and the process parameters i e initial concentration of the color precursors solution pH dosages of Fenton s reagent and reaction time According to the statistical analysis the optimized conditions for eachvariable in aqueous sucrose solutions including an initial concentration of the colorprecursors equal to 45 0 mg L 1 were as follows reaction time 30 min pH 5 8 Fe2 dosage 1 34 mM and H2O2 dosage 53 6 mM Under these conditions 61 8 of the colorprecursors and less than 2 5 of sucrose were degraded after 30 min of reaction Thehighest decolorization efficiency of the raw juice was obtained about 55 with theaddition of 1 34 mM Fe2 and 53 6 mM H2O2 at an initial pH of 6 2 Using the sameconditions approximately 92 of tyrosine was degraded in treated juice with Fenton sreagent Gel permeation chromatography analysis confirmed that the concentration of lowmolecular weight impurities in decolorized juice was considerably reduced According tothe results Fenton oxidation process can be considered as a promising method fordegradation of the color precursors and preparation of raw sugar beet juice with low colorcontent In the second part the purification of raw sugar beet juice was investigated byFenton oxidation along with conventional lime carbonation process During Fentonoxidation particular attention was paid to the effects of different dosage of Fenton sreagent and reaction time in order to improvement the quality properties of the raw juices Analysis of pre treated juices with Fenton s reagent showed that lower color and totalphenolic content of the raw juices were achieved with an increase in dosage of Fenton sreagent at a reaction time of 30 min especially for treatment 5 Concentration of colorprecursors especially tyrosine and ferulic acid were decreased significantly afteroxidation pre treatment In following a lime carbonation process was applied for the

جواد كرامت

ناصر همدمي، محمد حجت الاسلامي

علي نصيرپور، عبدالرضا حاجي پور، محسن لبافي مزرعه شاهي