بررسي اثر افزودن پودر كدوتنبل و كدو خورشتي بر خواص رئولوژيكي خمير و خصوصيات فيزيكي و حسي نان تافتون

چكيده انگليسي :

102 The Effect of Adding Pumpkin and Zucchini Powder on RheologicalProperties of Dough and Physical and Sensory Properties of Taftoon Bread Zahra Davudi z davudi@ag iut ac ir December 24 2013 Department of Food Science and Technology Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Mohammad Shahedi shahedim@cc iut ac irAbstractBread has always had a special place among the Iranian foodstuffs and constitutes the staple food of ourpeople Although bread has a significant role in supplying people s daily food needs it is not a completefood when used alone Therefore enrichment of flour and bread with vitamins minerals essential aminoacids and proteins can improve the bread nutritional value and hence its consumers diet Dietary fiber isone category of nutrients that can be used to enrich food s especially bakery products Fibersupplementation has been used to enhance the fiber content of a variety of foods ranging from cereal based products to meats imitation cheeses and sauces Numerous studies have demonstrated thebeneficial effects of fiber consumption in protection against heart disease and cancer modification ofblood lipids regulation of glucose absorption and insulin secretion and prevention of constipation Fruitsand vegetables such as pumpkin and zucchini are important sources of dietary fibers In this study inorder to produce the enriched Taftoon bread with pumpkin and zucchini the pumpkin and zucchinipowders were prepared and wheat flour was replaced with them in 5 10 and 15 levels The rheologicalproperties of the resulting dough were assessed by applying farinogeraph test extensogeraph test andextension of dough during fermentation Our results showed that the water absorption and expansion ofthe dough decreased during fermentation and the lowest magnitudes were observed in the 15 level ofzucchini and pumpkin powders respectively Furthermore it was observed that the stability time andtensile strength of the dough increased during fermentaion and the highest amounts were observed in the15 level of pumpkin and zucchini powders respectively After baking the bread from different dough chemical analyses color assessment volume staling and organoleptic tests were carried out Chemicalanalyses revealed the increased levels of ash and crude fiber in bread loaves with pumpkin and zucchinipowder substitution In addition results showed that replacing wheat flour with pumpkin and zucchinipowders caused the increase in the dough volume and staling and it was more pronounced in breadloaves with pumpkin powder substitution By replacing wheat flour with zucchini powder less increasewas observed in the dough staling and in the 5 level staling was minimal The a redness parameterof Hunter Lab system decreased in the case of zucchini powder fortified bread loaves and the b yellowness parameter of the samples containing pumpkin powder increased The result of organoleptictest indicated that the bread loaves with pumpkin and zucchini powders had better acceptability than theblank Best results were observed in the case of the 10 pumpkin powder samples Key words Pumpkin powder Zucchini powder Rheological properties Taftoon bread

داودي، زهرا

بررسي اثر افزودن پودر كدوتنبل و كدو خورشتي بر خواص رئولوژيكي خمير و خصوصيات فيزيكي و حسي نان تافتون