Physicochemical properties of commercial semi-sweet biscuit

This study was performed to provide information about the physical and chemical characteristics of commercial semi-sweet biscuits and to ascertain the key characteristics of commercial semi-sweet biscuits (rich tea type), in terms of starch properties, such as gelatinisation, pasting, granule crystallinity and morphology, and to compare the magnitudes of changes of physical characteristics (diameter, thickness, weight and bulk density) for selected brands. A total of 10 rich tea biscuits from different brands were bought locally and were measured for physical and chemical characteristics. The three-point bend test showed that a biscuit with lower fat content was harder than a biscuit with normal fat content, except for sample B. Starch gelatinisation properties show that To, Tp and Tc were higher than for wheat flour whereas ΔH was lower than for wheat flour. X-ray results showed that commercial biscuits still retained their crystallinity but at lower intensities than native wheat flour. Microscopy observations revealed that some of the granule birefringence of commercial biscuits can still be observed under polarised light. Different brands of biscuits showed different physical and chemical characteristics.