Asian noodles typically have high glycemic index, and an unbalanced diet heavily laden with carbohydrates has been linked to weight gain and obesity. Shirataki noodles from Japan is made from konjac glucomannan (KGM) and water and is widely known for its multiple health benefits and ability to promote satiety. However, it imparts negligible nutritional value due to its low energy content. In this study, the feasibility of making low calorie, gluten-free Shirataki noodles with improved nutritional value was shown by adding green banana flour (GBF), an underutilized subproduct of low commercial value and significance in the food industry. The optimal KGM-GBF noodles (with 6% w/w KGM, 35% w/w GBF) had 27% lower total energy content, 13% lower carbohydrate content, 5.4% higher fiber content, 2% higher ash content, and 80% hardness (as measured by texture profile analysis) when compared to commercial yellow alkaline wheat noodles. Multiple regression analysis showed that KGM level was a more influential factor than GBF level on the hardness of cooked KGM-GBF noodles (P < 0.01). The compatibility of GBF with KGM in noodle making lay in GBF's high gelatinizing and pasting temperatures, which allowed optimal KGM hydration during dough formation to develop the primary network structure in the noodles. Through this study, the potential of GBF as a functional food ingredient in product processing and nutrition enhancement was demonstrated. PRACTICAL APPLICATION: The addition of green banana flour can improve the nutritional value and sensorial properties of konjac (Shirataki) noodles. This offers a gluten-free and low glycemic index alternative to wheat and starch noodles currently available commercially. A novel method of noodle-making to create KGM noodles, without the use of high alkalinity, was developed.
Keywords: functional food; green banana; hydrocolloids; physical properties; starch.
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