Faeze Karami, Mehran Alami, Hoda Shahiri Tabarestani, Alireza Sadeghimahonak,
Volume 16, Issue 87 (5-2019)
Abstract
Cookies and biscuit might be included in the list of gluten-free products for patients with celiac disease However, most gluten-free bakery products are commercially based on pure starch, blend of maize starch and gluten-free flour, and protein which lead to dryness and sandy state of the final product. In this regard, there is a strong need to develop gluten-free cookies that are technologically complete as well as economical. The main purpose of this study was to investigate the functional properties of flours and different ratios of millet flour and rice flour (50:50, 25:75, 15:85, 0: 100) in the preparation of gluten-free cookies. Physicochemical properties of millet grain (moisture, fat, protein, ash, and fiber), flour (water absorption, oil absorption), and cookies (diameter, thickness, degree of expansion, color, and stiffness) were also investigated. The results showed that replacing rice flour with higher levels of millet flour led to an increase in water holding capacity (WHC) and decrease in oil absorption capacity (OAC), significantly (p<0.05). Higher amounts of millet flour showed a significant linear relation with degree of expansion in the cookies (p<0.05) and lightness (L*) of the samples decreased due to increased protein content and Millard reaction. Moreover, higher replacement of rice flour with millet flour in the cookies resulted in higher hardness and cooking loss but lower water activity and lightness(L*). The highest overall accessibility rate was for a cookie containing 15% millet flour
Faeze Karami, Mehran Ahami, Alireza Sadeghi Mahoonak, Hoda Shahiri Tabarestani,
Volume 16, Issue 88 (6-2019)
Abstract
Today, production and improvement of the quality of gluten-free products for Celiac patients are one of the major challenges in the food industry. Physical modification methods such as heat-moisture and microwave treatments can be used to improve the performance of flour and gluten-free products in the baking industry. The goal of this study was to investigate the effects of heat-moisture treatment at three relative humidity (RH) levels of 10, 15, 20% at 90 and 110 °C, to improve the quality of grain millet, and different ratios of of millet flour: rice flour (50:50, 25:75, 15:85) to be used in the formulation of gluten-free cookie. In this regard, physicochemical characteristics of millet (moisture, fat, protein, ash, fiber), flour (water absorption, oil absorption, color) and cookie (diameter, thickness, spread ratio, color, texture) were investigated. The results showed that the heat-moisture treatment had a significant effect on water holding capacity and oil absorption capacity of the samples (p<0.05), in a direct and reverse trend, respectively. Using flour from treated seeds in the gluten-free cookie improved baking loss, water activity, texture parameters, and sensory acceptance. By increasing heat-moisture treatment, the amount of baking loss, water activity and hardness of cookies decreased. Heat-moisture treatment had a significant effect (p˂0.05) on the spreadability and color of the cookies. Increase in the intensity of the treatment led to higher spreadability and darker color with high redness value The Sensory evaluation also showed that texture scores were high for most cookies made from treated millet flour, but the cookie obtained from the 25% replacement level of millet flour under 90 °C and 10% moisture content had the lowest score in the texture.
