Using buckwheat starch to produce slowly digestible biscuits with good palatability

Abstract Background and Objective Due to the rapid digestibility, cooked starch can cause a high postprandial blood glucose response (hyperglycemia), one of the risk factors for metabolic diseases, such as obesity and diabetes. The objective was to understand the properties of starch that provided slow digestibility in low‐moisture baked goods. Buckwheat ( Fagopyrum esculentum Moench) starch was used to prepare biscuits with slowly digestible starch and was compared with wheat ( Triticum aestivum ) starch. Findings Buckwheat starch had higher gelatinization temperature and smaller breakdown viscosity (in pasting curve) than wheat starch. Slower starch digestion rate and higher amount of undigested starch were observed when 60% (w/w) wheat flour in biscuits was substituted by buckwheat starch than by wheat starch. The biscuits containing buckwheat starch or wheat starch also showed a structure with lower firmness than the control biscuits. Conclusion Buckwheat starch was more resistant to gelatinization and breakage during baking, and thus was less susceptible to enzyme digestion in biscuits than wheat starch. Significance and Novelty This is the first study utilizing a starch having a normal amylose content without any modification, except partial gelatinization during baking, as a source of slowly digestible starch in biscuits. Buckwheat starch not only provided slow digestibility, but also improved the palatability of the biscuits, creating a smoother and less firm texture than those made using whole grain flour.