Roasting soybeans in a microwave for manufacturing chocolate dragées

Abstract

This study aimed to evaluate the effect of different microwave-roasting timeson different sizes of soybean grains with black tegument to achieve the best crunchiness, flavor, and hardness. Black soybean dragées– containing a soybean core coated with layers of chocolate (dragée) – were manufactured, and their nutritional value, microbiological risk, acceptability, and consumer-purchase intentions were verified. Flavor and crunchiness of the roasted black soybeans were only affected by the roasting time in the microwave, whereas the hardness was only affected by grain size. The best core of the dragéewas obtainedusing grains ofsieve size 15 (large grains) roastedin the microwave for 11 min; this core presented higher frequencies for extremely crunchy notes (56%), toasted flavor (61%), and an instrumental hardness close to that of the existing commercial product (33.17 N). The manufactured dragées did not present resistant starch, anthocyanins, and microbiological risk, and they were sensorially accepted by the tasters (mean scores of 7.77 for texture and 8.36 for appearance on a scale of 1 to 9). Thus, roasted black soybean dragéeshave a high marketing potential from technological, nutritional, and sensorial points of view.