Physicochemical properties and sensory evaluation of gluten-free cookies made from fermented adlay (Coix lacryma jobi L.) flour using Rhizopus sp.

Native adlay flour lacks the characteristics that give it grittiness when applied to food products, which can be improved by flour modifications using the fermentation method. This study aimed to evaluate the characteristics of new gluten-free cookies made from native and modified adlay flours and compare them to those made from wheat flour. Adlay flour was modified by fermentation using various Rhizopus sp. inoculum concentrations: 0.5%, 1%, and 1.5% (w/w). The modified adlay flour using 1.5% (w/w) Rhizopus sp. inoculum was selected for application in making gluten-free cookies because of its most suitable characteristics, including lower pasting temperature, resistance to retrogradation, good thermal stability, and favorable functional properties such as high swelling volume, solubility, and water and oil absorption capacities. In making cookies, the treatments were the type of flour used, namely native adlay flour cookies (NAFC), modified adlay flour cookies (MAFC), and wheat flour cookies (WFC) as a control. All cookies were made using the same recipe; the only difference was the type of flour used. The results showed that MAFC has higher fat and crude fiber however lower protein content than WFC. The MAFC was not significantly different (p >= 0.05) from WFC in hardness and fracturability. The sensory evaluation showed that MAFC did not have significant differences (p >= 0.05) in texture, mouthfeel, aftertaste, and overall acceptance compared to WFC. Fermentation modification of adlay flour can eliminate grittiness in gluten-free cookies.