Reducing fat absorption in fried foods using edible films

This thesis investigates the use of edible films to reduce the fat absorption in fried foods. The edible films studied were gellan gum, methyl cellulose and hydroxypropyl cellulose. All three films were found to reduce the fat absorption into the food by 50 to 90%. A mathematical model was developed incorporating heat, moisture and fat transfer in both the food and the film. Moisture diffusivities of the food and the film were found to be 0.33 {dollar}times{dollar} 10{dollar}sp{lcub}-7{rcub}{dollar} m{dollar}sp2{dollar}/s and 0.25 {dollar}times{dollar} 10{dollar}sp{lcub}-7{rcub}{dollar} m{dollar}sp2{dollar}/s, respectively. Fat diffusivities were found to be 0.103 {dollar}times{dollar} 10{dollar}sp{lcub}-8{rcub}{dollar} m{dollar}sp2{dollar}/s for the food and 0.604 {dollar}times{dollar} 10{dollar}sp{lcub}-9{rcub}{dollar} m{dollar}sp2{dollar}/s for the film. Thermal diffusivities were found to be 0.102 {dollar}times{dollar} 10{dollar}sp{lcub}-6{rcub}{dollar} m{dollar}sp2{dollar}/s for the food and 0.156 {dollar}times{dollar} 10{dollar}sp{lcub}-6{rcub}{dollar} m{dollar}sp2{dollar}/s for the film. Film diffusivities are for gellan gum films at a thickness of 2.0 mm during frying. The fat and moisture diffusivities of the gellan gum film were found to increase with an increase in film thickness.