Sensory Evaluation of Ice Cream Made with Prebiotic Ingredients Substituted for Sugar

Adviser: Julie Albrecht Prebiotics are non-digestible food ingredients that beneficially affect the host by selectively stimulating growth and/or activity of beneficial bacteria in the colon. The project objective was to determine consumer acceptability of ice cream with prebiotic ingredients substituted for part of the sugar and to determine sensory attributes of sweetness, smoothness, and vanilla flavor. A commercial ice cream mix was made substituting 0%, 10%, 20%, or 30% of the sugar for either Fructooligosaccharides (FOS) or inulin. Sensory analyses were conducted using 95 non-trained panelists. Overall consumer acceptability and sensory attributes were measured on a 175 mm anchored hedonic scale. When 10% and 20% inulin ice cream were compared to the control (0%), no significant differences in sweetness, smoothness, vanilla flavor or overall acceptability were found (P < 0.05). The 30% inulin ice cream was significantly less sweet than the control and 10% and 20% inulin ice cream, less smooth and less vanilla flavor than the control, and less acceptable than the control and 10% inulin ice cream (P < 0.05). For 10% and 20% FOS ice cream, no significant differences were found in sweetness, smoothness, vanilla flavor or overall acceptability compared to the control (P < 0.05). The 30% FOS ice cream was significantly less sweet than 10% FOS ice cream but not significantly different than the control or 20% FOS ice cream (P < 0.05). The 30% FOS ice cream was significantly less smooth than the control, 10% and 20% FOS (P < .05). Vanilla flavor was not significantly different. Overall acceptability was significantly less for 30% FOS compared to the control and 10% FOS ice cream but not significantly different than 20% FOS (P < .05). These results suggest that FOS and inulin may be acceptable ingredients in ice cream when substituted for up to 20% of the sugar. i Acknowledgements I would like to thank Laurie Keeler, Senior Manager for Food Technology Transfer of University of Nebraska-Lincoln Food Processing Center for her technical expertise in ice cream production and David Girard, Research Technologist for his assistance during sensory evaluation. ii Table of Contents Page Chapter 1 Review of literature Health concerns 1 Functional foods may improve health 2 Probiotics 2 Understanding bifidobacterium 3 How colonic bifidobacteria are established 4 The role of bifidobacteria in human health 5 The role of prebiotics in human health 7 Bifidogenic properties of inulin-type FOS 12 FOS in infant formula …