Abstract
The seed coat of Adzuki bean, which is removed for producing Adzuki bean jam, can be dried and milled for potential use, as a food material. We studied the effects on quality of adding the powdered seed coat and konnyaku gel to the mix for baked muffins.
The average yield of the powdered seed coat was 28.8%. The water-holding capacity and oil absorption of the powdered seed coat were respectively 3 times and 1.6 times higher than those of soft wheat flour. The powder contained a large amount of such functional components as dietary fiber, mineral compound, and polyphenols. Observation of the tissue by scanning electron microscopy indicated depressions and wrinkles on the surface of the powder particles, unlike that of wheat flour. Compared with the control muffin (no powdered seed coat added), the muffin with up to 20% of wheat flour replaced by the powdered seed coat had the hue of adzuki beans, small specific volume, hard and brittle texture inside, and was more preferred in flavor, taste and overall rating. The further addition of konnyaku gel to the muffin mix at 2.2% was favorable for the baked texture and preservation characteristics.
