Evaluation of chemical composition and cooking properties of Turkish type gluten-free rice couscous

In this study, the aim was to produce traditional couscous in gluten-free form. For this purpose, rice flour (RF) and pre-treated (gelatinized) rice flour (GRF) were added in varying proportions (15, 20, 25, and 30%) to the recipe instead of gums and enzymes in order to provide the desired structure. The control sample without GRF was also produced. With the addition of GRF, the total dietary fibre (TDF) content in the couscous samples increased, and reversely the carbohydrate and energy values decreased. The GRF reduced the level of total soluble organic material (TSOM) as well as the cooking loss of the couscous samples, which resulted in lower deformability. According to the results, the gluten-free rice couscous was successfully produced with GRF, especially at a 30% ratio. Good cooking properties were observed in these couscous samples. In this context, in the addition of 30% GRF, higher water absorption and swelling volume with lower cooking loss were observed compared with the control sample. In addition, the couscous samples had higher ash, dietary fibre and fat content as well as a lower phytic acid ratio (P < 0.05). It was determined that there was significant correlation between the cooking time of the samples with the cooking loss and total soluble organic material. According to the results, the PCA showed that there were clear correlations between cooking trials (water absorption and swelling volume) and chemical composition (moisture, ash, crude fat, and TDF).