Abstract: In order to study the effect of different grain sizes of potato flour on the quality of wheat based composite noodles which were made from wheat flour with potato flours of different grain sizes added. The results showed that with the decrease in grain size of potato flour, the water absorption of noodles during cooking decreased first, reaching a minimum value at 150 mesh grain size, and then increased. However, the opposite trend was noted for starch dissolution rate, elasticity and chewiness exhibited an initial increase and a sequential decrease, and then with maximum values being observed at 150 mesh grain size. Hardness also first increased until reaching a maximum at 100 mesh grain size, and then decreased. In addition, porosity decreased first and then increased, while the content of bound water increased first and then decreased, reaching minimum and maximum values respectively at 200 mesh grain size. In the grain size range tested in this study, the effective diffusion coefficient of water in noodles was in the range of 1.92 × 10-9-2.62 × 10-9 m2/s. The addition of potato flour with grain size equal to or slightly smaller than that of wheat flour is better for improving the quality of noodles.

Key words: potato flour, composite flour noodles, quality, particle size