Jackfruit seeds are an underutilized waste in many tropical countries. This work demonstrates the potential of roasted jackfruit seeds to develop chocolate aroma. Twenty-seven different roasted jackfruit seed flours were produced from local jackfruit by acidifying or fermenting the seeds prior to drying and then roasting under different time/temperature combinations. The chocolate aroma of groups of four flours were ranked by a sensory panel (n = 162), and response surface methodology was used to identify optimum conditions. The results indicated a significant and positive influence of fermentation and acidification on the production of chocolate aroma. SPME/GC-MS of the flours showed that important aroma compounds such as 2,3-diethyl-5-methylpyrazine and 2-phenylethyl acetate were substantially higher in the fermented product and that the more severe roasting conditions produced 2-3 times more 2,3-diethyl-5-methylpyrazine, but less 3-methylbutanal. Moisture, aw, pH, luminosity, and color were also monitored to ensure that these properties were similar to those of cocoa powder or cocoa substitutes.
Keywords: SPME/GC-MS; chocolate aroma; jackfruit seeds; sensory analysis; waste utilization.