Optimization of sugar-free konjac gel texture containing erythritol-sucralose sweetener for producing healthy jam

The understanding of textural characteristics of gels, which replace for sugar with sugar substitute, is essential for designing gel-based healthy food products.This research aimed to investigate the changes in textural characteristics as well as to optimize the gel condition of sugar-free konjac gel using the response surface methodology.A central composite rotatable design was implemented to determine the texture profile analysis, including the hardness, cohesiveness and springiness.Two independent variables, comprising different levels of konjac flour-to-xanthan ratio (25:75 to 50:50 w/w) and erythritol-sucralose (ES) concentration (0.2-2.5% w/v), were studied.Konjac gels showed an increase in all textural characteristics when increasing the konjac content, while a slight change was induced by ES.The optimized konjac gel condition was tested for its characteristics and acceptability as pineapple jam, during the storage for 30 days at refrigerated temperature (10-12°C).The low-sugar jam made with ES was acceptable and showed its overall acceptability score in a moderate preference.Both sucrose and ES jams were firmer and brighter during storage.After refrigeration for 30 days, both products showed lowered liking scores for some sensory attributes; however, they were microbiologically safe.