Physical properties, palatability, and mastication of breads with different compositions of soy protein isolate and soybean soluble polysaccharide

Breads with different compositions of wheat flour (WF), soy protein isolate (SPI), and soybean soluble polysaccharide (SSPS) were prepared, and the relationships between their physical and nutritional properties, mastication, palatability were investigated and tests on elderly and young human subjects were conducted. Bread mixed with only SPI (SP1) showed a reduced specific volume and was hard, possibly making it difficult for elderly individuals to swallow. When 10 g of SPSS was added to the mixture (SP2), the bread improved in specific volume, became soft and moderately hard, and was as palatable as regular bread (control; without SPI and SPSS) for younger and older people. However, when 20 g of SSPS was added (SP3), the adhesiveness increased and palatability was impaired. In addition, SP2 bread required increased number of chews and chewing time compared to that required for control bread in older people but the difficulty of swallowing was similar for both in the sensory evaluation. SP2 bread can increase the intake of protein and dietary fiber and increase the number of chews without affecting palatability, and SPI and SSPS mixed bread was considered useful for maintaining the chewing ability and nutritional status of older people.