Enhancing the nutritional value of traditional thai glutinous rice crackers (Khao Kriap Wow) with black glutinous rice flour

Khao Kriap Wow (KKW) is a traditional Thai glutinous rice cracker that is low in nutrition due to its primary ingredients of white glutinous rice flour and sugar. This study investigated the effect of partially substituting white glutinous rice flour with black glutinous rice flour on the physicochemical properties, nutritional composition, and consumer acceptability of KKW. Four substitution levels (10–25%) were evaluated following the selection of an optimal basic formulation. Increasing substitution levels resulted in decreased lightness (L*) and yellowness (b*), but increased redness (a*), hardness, and dietary fiber. Nutritional analysis demonstrated higher protein, fat, dietary fiber, calcium, iron, and vitamin A contents, alongside slight reductions in energy and carbohydrate levels. Sensory evaluation and consumer testing (n = 100) indicated that formulations up to 20% substitution maintained acceptable appearance, flavor, crispiness, swelling, and overall liking. Principal Component Analysis and Partial Least Squares Regression revealed positive associations between consumer preference and lightness, expansion ratio, and post-baking moisture, whereas higher nutrient density correlated with increased hardness. The 20% formulation (F3) provided the best balance between improved nutritional quality and desirable sensory attributes, demonstrating the potential of black glutinous rice flour as a functional ingredient for enhancing traditional Thai snack products.