Evaluation of physico-chemical and functional properties of composite flour from cassava, rice, potato, soybean and xanthan gum as alternative of wheat flour.

This work aims at examining the physical, chemical and functional properties of composite flour produced with cassava, rice, soybean flours, and potato starch and added with 0.5% xanthan gum. Nine blends of composite flours were prepared by homogenously mixing rice flour, cassava flour, soybean flour, and potato starch (RF:CF:SF:PS) in the proportions of 30:50:15:4.5, 30:45:20:4.5, 30:40:25:4.5, 30:45:15:9.5, 30:40:20:9.5, 30:35:25:9.5, 30:40:15:14.5, 30:35:20:14.5, 30:30:25:14.5. Composite flour produces were subjected to proximate, paste and functional properties analyses. The moisture content, fat, protein, ash and crude fiber of the composites were as follows: 9.37-12.07% db, 1.33-4.91%, 4.50-6.22%, 0.74-1.12% and 1.13-1.94% compared with wheat flour 13.32% db, 6.30%, 2.12%, 1.31% and 7.52%, respectively. There was no significant difference (P > 0.05) recorded for water absorption index and gelatinization temperature between nine blends of composite flours and wheat flour. Peak, set back, cooling capacity and breakdown viscocisity were: 2311.67-4423.00 cP, 1199.33-1556.33 cP, 2618.67-3415.00 cP and 992.00-2437.67 cP. The value of composite flour viscosities were higher than paste characteristics of wheat flour. The colour of composite flour showed by the L * value of chromameter were 95.71-97.10 compared with wheat flour 95.02. Hence, it was concluded that the composite flours from rice, cassava, and soybean flour, potato starch using xanthan gum had the physicochemical and functional properties which can be considered similar to wheat flour for making wheatless products. The composite flour with the proportion of rice flour 30%, cassava flour 40%, potato starch 15%, soybean flour 14.5% and xanthan gum 0.5% had the physicochemical, functional and pasting properties that comparable to those of wheat flour.