7602

7074

كارشناسي ارشد

علوم و صنايع غذايي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1391

دوازده،129ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

جواد كرامت، اميرحسين گلي

مهدي كديور

19/1/92

علي نصيرپور، رحمان جهانيان

مهندسي كشاورزي

ID7074

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Abstract Oxidation is a major reason of deterioration in foods leads to reduction of nutritional value and quality The produced free radicals from oxidation increase the risk of human diseases Application of the natural antioxidants is a useful way for prevention of creation of these compounds These antioxidants not only such as BHA and BHT aren t synthetic but also promote the consumer health Nowadays edible and environmental friendly films are alternative to other packaging materials such as plastic ones These films can be used as carriers of the nutritional ingredients i e vitamins and mineral preservation materials i e antimicrobials and antioxidants and flavoring and coloring agents These additives can increase the functional and preservative properties of films The current study was designed to evaluate the antioxidant activity of essential oils EOs of clove oregano and sage herbs comparing to BHT The antioxidant activity of the EOs was investigated using DPPH 2 2 diphenyl 1 picrylhydrazyl free radical scavenging carotene linoleic acid assay and reducing power methods Different concentrations of EOs 200 400 600 800 and 1000 ppm and BHT 100 and 200 ppm were added to the soybean oil Then the antioxidant added soybean oil was stored at an accelerated storage condition to speedup oxidation 60 C 30 days Moreover the antioxidant activity of EOs was also determined by measuring their peroxide value PV and tiobarbitoric acid TBA during 30 days of storage The EOs was separately added to aqueous Hydroxyl propylmethylcellulose HPMC HPMC films were prepared from the EO added solutions the ratio of HPMC glycerol Tween 80 EO was 1 0 5 0 05 0 1 w w The control film was prepared without adding EO The mechanical optical properties and water vapor WVP oxygen permeability OP of films was also investigated Subsequently the antioxidant activities of films against soybean oil oxidation were evaluated during 60 days storage at 40 C by measuring the PV For all of tests the highest antioxidant activity was observed for clove and which was followed by BHT oregano and sage as respectively EOs was able to reduce the oxidation rate of soybean oil and showed more antioxidant effect comparing to control sample The EOs causes a significant decrease of WVP and OP of films The sage EO added films S F had lowest water vapor permeability which was followed by oregano EO added film O F clove EO added film CL F and control films CO F More effective in decreasing film OP was observed in order to O F S F CL F CO F In general addition of EO into HPMC film led to decrease of transparency tensile strength TS elongation percentage E and elastic modulus EM of the composite films The lowest TS and EM was observed for the O F which was followed by S F and CL F the CO F had highest TS and EM Moreover highest E was observed in order to CO F S F O F and CL F These films containing EOs reduced soybean oil oxidation during storage significantly CL F was more effective against soybean oil oxidation which was followed by O F S F and CO F In general the antioxidant activity of EOs added films was lower effect than direct addition of EOs into soybean oil Keywords Natural antioxidants Hydroxypropylmethyl cellulose HPMC Edible Film Essential Oil Clove Oregano Sage Soybean Oil

جواد كرامت، اميرحسين گلي

مهدي كديور

علي نصيرپور، رحمان جهانيان