توليد اولئوژل با استفاده از زيست پليمر‌هاي زانتان و ژلاتين به روش توليد كف

چكيده انگليسي :

Oleogel production using biopolymers of xanthan and gelatin by foam templated method Maryam Abdollahi Maryam abdollahi@ag iut ac ir December 26 2018 Department of Food Science and Technology Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language Persian1st Supervisor Sayed Amir Hossein Goli amirgoli@cc iut ac irAbstractIn recent years following the unfavorable effects of saturated and trans fatty acids on humanhealth a new method of producing oleogel to create a structure in liquid oils which allows thereplacement of solid fat with this network without changing the texture of the product has beenconsidered The use of biopolymers to structure liquid oil according to the nutritional value ofmany polymers is a promising solution However many food polymers are inherentlyhydrophilic Hence indirect methods such as foam templated approach have been investigatedto produce oleogel in non thermal process The present study was done in three parts Firstly solutions were prepared at different concentrations of gelatin 3 and 5 and xanthan gum 0 0 1 and 0 2 and their physical properties were studied Further the physical properties ofcryogels at different concentrations were also evaluated followed by freeze drying of solutionsand forming the porous structure of cryogel The results showed that the presence of xanthansignificantly increased the solution viscosity whereas it did not show any significant effect onoverrun and foam stability Also an increment in the biopolymer concentrationsincreased network density and firmness of cryogel but did not show a significant effect onmoisture sorption during the time The oil sorption capacity of cryogels demonstrated that thepresence of xanthan gum and network compact could affect the oil absorption of samples sothat the samples containing xanthan gum with low network density absorbed oil up to 50 timesof their own weight In second part due to determined characteristics the oleogel containing3 gelatin and 0 2 xanthan was selected as the best sample and used for complementary testssuch as microstructure colorimetric FTIR rheology storage stability and oil binding capacityat different temperatures The results obtained from microstructure and spectroscopy studiesexhibited that hydrogen bonding originated from biopolymers was effective in formation ofsemi crystalline structure of oleogel In addition the oleogel showed thixotropic behavior 60 structural recovery and desirable gel strength at temperatures below 100 C Also the oleogelcan protect edible oil from oxidation reactions within 2 months of storage In the third section enriched vitamin D oleogel was prepared and vitamin stability during 45 days of storage atdifferent temperatures 25 and 40 C and vitamin D release was investigated using highperformance liquid chromatography The results showed that the presence of biopolymersnetwork in short terms of storage had no significant effect on vitamin D stability while it canaffect the controlled release of vitamin in comparison with oil According to the results gelatinand xanthan gum oleogel prepared in a non thermal way can be used as a replacement of solidfats and carrier of bioactive compounds in food products Key Words Xanthan Gelatin Cryogel Oleogel Oxidative stability Rheology Release 64

عبداللهي، مريم

توليد اولئوژل با استفاده از زيست پليمر‌هاي زانتان و ژلاتين به روش توليد كف

زانتان , ژلاتين , كرايوژل , اولئوژل , پايداري اكسيداتيو , رئولوژي , رهايش