Evaluation of alkalization process in the making of chocolate substitute from durian seed waste

Previous studies have investigated fermented jackfruit seed and carob flour as potential cocoa powder substitutes, but none have been able to completely replace cocoa powder in food products. The utilization of fermented durian seed as a cocoa powder substitute has shown promise, with the ability to fully substitute cocoa powder in baked brownie production while maintaining good consumer acceptance, although the color was noticeably lighter. In the current research, various fermentation media and alkalization processes were employed with the aim of enhancing the sensory characteristics of the durian seed powder. The fermentation was conducted at room temperature for 7 days under anaerobic conditions, using different ratios of ripe durian pulp and okara (1:0, 1:1, and 0:1) added with 3% Saccharomyces cerevisiae. The alkalization process was conducted by using either 3% NaOH, 3% K2CO3 or without alkalization. All the alkalized and non-alkalized fermented durian seeds were dried, roasted at 180°C for 40 min, ground, and sieved at 200 mesh. From the sensory analysis, the optimal fermentation medium was 100% ripe durian pulp with the alkalization process. NaOH, as the alkali solution, can enhance the aroma and color of the fermented durian seed powder. The alkalized fermented durian seed that was fermented using 100% ripe durian pulp and alkalization process with 3% NaOH exhibited a chocolate aroma that was not significantly different from that of classic and dark commercial cocoa powders with Chroma value of 20.07±0.38 and °Hue of 67.72±0.45, which fall into the color range of yellow red. The alkalization process was able to enhance the similarity between the cocoa powder substitute made from durian seed and commercial cocoa powder, demonstrating the potential for utilizing durian seed waste as a cocoa powder substitute.