Kiwi starch: A novel fruit-derived starch with significantly reduced the glycemic index of noodles

Kiwi starch (KS) is the starch-based ingredient with good potential for developing low glycemic index (GI) staple food. This study evaluated the quality changes in composite flour, dough, and noodles induced by 10-30% KS substitution levels. The results revealed that KS substitution could promote water absorption and pasting of composite flour system, while enhancing the viscoelasticity and microstructural denseness of the dough. Additionally, adding KS increased hardness (181.51-193.48 g), gumminess (128.60-138.19 g) and chewiness (117.64-131.16 g) of the noodles, and decreased springiness (0.94), resilience (0.27-0.30), breaking force (46.85-69.64 g) and tensile displacement (7.41-10.69 mm). Overall, in the experimental dose range, adding KS did not adversely affect the aroma, taste, and overall acceptability of noodles, but had a negative effect on the texture. Notably, KS substitution enriched the variety of noodles while decreasing the starch hydrolysis rate and expected glycemic index (eGI). After 30% KS addition, the noodles were transformed from high GI (86.95) to medium GI food (69.46), with no significant difference in eGI against the noodles made from 30% buckwheat starch (BS) (67.69), a low GI starch ingredient that has been successfully commercialised. In summary, our findings present a possibility for developing new low GI noodles.