Effect of potato flour on quality and staling properties of wheat-potato flour bread.

To elucidate the impact of potato flour (PF) on quality changes and staling characteristics of the composite bread from wheat-potato flour (WPF), the physicochemical (specific volume, colority, sensory value, texture, and viscosity) properties, and staling (X-ray diffraction and water migration) properties of bread were investigated. The quality of composite bread was comparable to wheat bread when addition level of PF at 20%, but decreased when the addition level increased to 30% or more, and became unacceptable at 50%. A chewy mouthfeel and an elastic and none-crumbly texture were observed on composite bread, which had higher hardness than wheat bread, and could keep on both longer linear distance and higher linear force during compression test. It indicated that such new parameters other than hardness should be introduced to coordinate with the texture quality of composite bread. During storage, the higher addition level of PF significantly decreased crystallinity of composite bread and slowed water migration rate from the crumb to crust, suggesting that PF had antistaling effect on composite bread, which was further emphasized by the fact that the setback value of the WPF decreased with the increase of PF addition.