Relationship between consumer preferences and the water/sugar content of sweet bean paste products

The water content, sugar content, and physical properties of five commercially available sweet bean paste products were measured and sensory evaluations were conducted. The results showed that most commercially available sweet bean products had a water content of 35 %-50 %. The higher the water content of the sweet bean paste, the harder the texture of the paste, and this leads to reduced sweetness. Because the: sweetness level perceived by consumers is influenced by the texture of the sweet bean paste, the amount of sugar to be added must be calculated based on the water content of the sweet bean paste. Generally, a higher water content disperses the sweet bean paste particles, increasing the fluidity and softness of the resulting paste. Conversely, the results obtained for commercially available sweet bean paste products was unexpected. To clarify the reasons for this discrepancy, sweet bean paste samples with adjusted water or sugar content were prepared using the same raw materials. The prepared samples were analyzed in the same manner as the commercially available products. The results showed that as the water content increased, the samples became softer and melted better in the mouth. There was no difference in texture of the prepared samples and the commercially available products. When the water content was adjusted to 40% and the sugar content was increased, the samples became softer, had a smoother texture, and melted better in the mouth. This suggests that the samples with 40 % water content, 40 % sugar content, and high palatability provide consumers with moderate hardness, better melting in the mouth, a smooth texture, and optimal sweetness when used as filling in Japanese sweets and sweetened buns. The "hardness" of the sweet bean paste and its effect on melting sensations in the mouth, texture, and moderate sweetness is an important factor affecting consumer preference. Our findings revealed a relationship between the water and sugar contents of sweet bean paste and consumer preference. In contrast, even at higher water content levels, some samples had the same hard texture as the commercially available products. The hardness of sweet bean paste is considered to be affected primarily by the extent to which the particles in the sweet bean paste are distributed. Therefore, the impact of the manufacturing process and raw materials on the hardness of sweet bean paste should be clarified further. Furthermore, the relationship between the dispersed state of the particles, the physical properties of sweet bean paste, and consumer preferences should be thoroughly investigated.