Effect of formulation on rice noodle quality: Selection of functional ingredients and optimization by mixture design

• Modified rice flour was satisfactorily applied to produce laminated rice noodles.
• Gelatinized rice flour and starches conferred rice pasta a good mechanical behavior.
• Synergistic effects among functional ingredients could be verified by mixture design.

The aptitude of seven functional ingredients was evaluated by applying the tensile strength test on cooked noodles. Each formulation included the functional ingredient; modified rice flour obtained by planetary ball milling; and water. Gelatinized rice flour and its blends with gelatinized corn starch; xanthan gum; and guar gum provided a satisfactory mechanical behavior. Pasta formulation was optimized by mixture design, which included seven combinations of gelatinized corn starch, xanthan gum and guar gum. Each combination (8.5%) was blended with modified rice starch (86.7%) and gelatinized rice flour (4.8%) as dry ingredients. Synergistic effects between gums could be detected. Optimum mixture (7.8% gelatinized corn starch, 0.7% guar gum without xanthan gum) obtained by maximizing strain at break (17.9%) and simultaneously minimizing cooking loss (13%) also showed satisfactory values of water absorption (58.7%) and stress at break (31.5 kPa). The capacity of gelatinized rice flour and gelatinized corn starch to induce starch network formation was enhanced by the pre-gelatinized character of modified rice flour. The use of gums in pasta formulated with thermo-mechanical modified rice flour could be significantly reduced by substituting them partially with gelatinized corn starch, without reduction of noodle quality.