Establishing the function of proteins on the rheological and quality properties of 1 rice based gluten free muffins

8 The incorporation of proteins has been long established in the bakery industry to obtain 9 enriched products, but they also take active part on the making process of sweet baked 10 goods. This study was focused on assessing the role of proteins on the rheology and 11 quality of wheat free muffins by using rice flour. Six rice based formulations were used: 12 one without added protein (No-Protein) and five with different protein sources: soy 13 protein isolate (SPI), pea protein isolate (PPI), egg white protein (EWP), casein(C), and 14 for comparing purposes vital wheat gluten (VWG) was included. Proteins effects were 15 established by evaluating the rheological behaviour of batters measuring the storage 16 modulus (G′) and the loss modulus (G′′), and the technological characteristics of the 17 muffins obtained (specific volume, colour, and texture). The addition of SPI, PPI and C 18 significantly (P<0.05) increased G′, but this was not modified in batters containing 19 EWP. Casein and EWP increased the specific volume of the muffins. SPI did not have 20 effect on hardness, springiness, cohesiveness, chewiness, and resilience of the muffin, 21 while PPI containing muffins were softer and springier. The overall results indicated 22 that both the rheological properties of the batters and the technological characteristics of 23 the muffin are dominated by the presence of the type of protein used in the 24 formulations. Therefore the source of protein included in the formulation is fundamental 25 to ensure the proper texture and other technological properties of these products. 26