Investigation of sensory and instrumental methods to predict shelf-life of jelly gums

Tireki, Suzan
The main aim of this study was to correlate sensorial changes with instrumental techniques to predict shelf life during storage of jelly gums. Effects of glucose syrup:sucrose ratio, starch and gelatine content on quality and sensorial properties of jellies were investigated. Glucose syrup: sucrose ratio, starch and gelatine contents affected hardness significantly. Moisture content, water activity, total soluble solids, pH, springiness and gumminess was influenced by only glucose syrup:sucrose ratio. Moisture content changes after a week at 30°C were similar to those after 8 weeks at 15-22°C. At 30°C, the rate of change in water activity was more than double as compared to 10°C and 20°C. Formulations with glucose syrup:sucrose ratio of 1.5 were more stable in terms of pH and colour. Glass transition temperatures increased after storage. Formulation with glucose syrup:sucrose ratio of 1.5, no starch and 6% gelatine was the most stable formulation in terms of hardness and gumminess. Moisture diffusion coefficients were determined to be between 5.93×10-10m2/s and 5.46×10-10m2/s. In sensory analysis, starch content was more effective on appearance and gelatine was more effective on texture of jellies. Storage of about 8 weeks at 30°C was equivalent to storage of 52 weeks at 15-22°C when sensory taste liking was correlated with sugar profile. Therefore, 30°C could be selected for accelerated shelf life testing. Jellies with no starch, 6% gelatine and glucose syrup:sucrose ratio of 1.5 had the most stable formulation in terms of critical parameters with high sensory scores and shelf life was determined as 52 weeks. 


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Citation Formats
S. Tireki, “Investigation of sensory and instrumental methods to predict shelf-life of jelly gums,” Ph.D. - Doctoral Program, Middle East Technical University, 2017.