Noodles made from blends of rice flour and pineapple stem starch: physical properties, cooking qualities, in vitro starch digestibility and sensory properties

Abstract

Noodles are generally made from rice flour, wheat flour or mungbean starch. Interestingly, pineapple stem starch (PSS), an alternative starch derived from pineapple stems as agricultural waste, has not yet been investigated for noodle production. The noodles were then prepared in different ratios of commercial rice flour and PSS (100:0, 70:25, 50:50, 25:75 and 0:100) to investigate the effects of PSS on noodle qualities and properties including physical properties, cooking quality, in vitro starch digestibility and sensory attributes. The results showed that high PSS content had a positive effect on the structure and textural properties of noodles by increasing the network structure, hardness and chewiness, resulting in good sensory quality, which could be due to the high amylose content (30.56%) of PSS. However, the optimal cooking time and the cooking loss of the cooked noodles increased with an increasing proportion of PSS. In addition, noodles with a high PSS content had a higher content of slowly digestible starch and resistant starch, which can have a positive effect on our health. Our results suggest that PSS, an alternative starch from agricultural waste, can replace rice flour to develop better-quality gluten-free noodles. Similarly, PSS-based noodles with a high resistant starch content could benefit human health by lowering the glycemic index and reducing the risk of non-communicable diseases.