10942

10079

كارشناسي ارشد

علوم و صنايع غذايي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1394

دوازده، 82ص.: مصور

هاجر شكرچي زاده، مهدي كديور

اميرحسين گلي

1394/11/03

جواد كرامت، مهدي رحيم ملك

مهندسي كشاورزي

ID10079

منابع 67 چكيده انگليسي 98 ده

89 Production and Evaluation of Alginate Hydrogel Containing Lemon balm Extract as Antioxidant Compounds Delivery agent Samira Najafi Soulari s najafi@ag iut ac ir December 28 2015 Department of Food Science and Technology Isfahan University of Technology 84156 83111 IranDegree M Sc Language FarsiSupervisors H Shekarchizadeh shekarchizadeh@cc iut ac irM ahdi Kadivar kadivar@cc iut ac irAbstractNatural polyphenols are valuable nutritional compounds They are antioxidants which can scavenge freeradicals and prevent cancer and many other diseases However these natural ingredients do not have highstability during time and are very sensitive to light and heat On the other hand some of thesepolyphenols are very bitter So their use in foods or drugs is limited Encapsulation is a hopeful approachfor solving these problems Lemon balm which has phenolic compounds and antioxidant effect and alsocreates lemon aroma is a good choice to produce functional foods In this study lemon balm extract as asource of natural antioxidants was encapsulated in the calcium alginate hydrogels To optimize theencapsulation process three variables of alginate percentage calcium chloride concentration and thelemon balm extract concentration were used at three levels The results showed that maximumencapsulation efficiency was achieved in 1 84 alginate solution concentration 0 4 lemon balmextract concentration and 0 2 calcium chloride concentration The maximum encapsulation efficiencyand loading capacity of extract in alginate hydrogels were 39 5 and 14 36 mg g respectively Encapsulation efficiency and loading capacity were reduced to 26 97 and 12 83 mg g by applyingchitosan coating on the surface of hydrogels The antioxidant activity of the lemon balm extract of 0 4 and the encapsulated extract were calculated 84 5 and 36 5 respectively Release of extract in thesimulated gastrointestinal systems was investigated Results showed that most of antioxidant compoundswere released in the gastric fluid Chitosan coating reduced the release of extract from 71 59 to 51 78 indicating this coating acts as a barrier Scanning electron micrographs showed the surface structure of thealginate hydrogels FTIR spectra of hydrogels with and without lemon balm extract showed that thehydrogel did not make new connection with lemon balm extract Therefore the alginate hydrogel is asuitable material for encapsulation of active compounds Keywords Encapsulation Lemon balm extract Alginate hydrogel Chitosan

هاجر شكرچي زاده، مهدي كديور

اميرحسين گلي

جواد كرامت، مهدي رحيم ملك