Sensory Acceptability of Instant Noodles Cooked in a Calcium Oxide–Water Based Self-Heating Container: Effect of Reactant Proportion

Abstract:

Ready-to-eat (RTE) noodles require short but unavoidable cooking before consumption, which limits their convenience in situations without culinary facilities. A self-heating container utilizing the exothermic reaction between anhydrous calcium oxide (CaO) and water (H₂O) was developed to enable in-package cooking of instant noodles. This study evaluated the sensory acceptability of noodles cooked in a container using two reactant combinations. Noodles (60 g) cooked with 120 mL water were prepared in a single-shell container with the reactant chamber positioned below the product bowl. Two CaO:H₂O combinations, 125 g:75 mL (T8) and 150 g:75 mL (T11), previously identified as capable of attaining the target cooking temperature, were used to cook the product for six minutes; a conventionally cooked sample served as control. Color, flavor, body and texture, appearance, and overall acceptability were rated by a trained sensory panelist on a 9-point hedonic scale, and the data were analyzed using a Completely Randomized Design. The control group scored the highest for all attributes. T11 approached the control and scored significantly higher than T8 for color, body and texture, and appearance (P<0.05), while the flavor scores of the control, T8, and T11 were statistically comparable. T8 recorded the lowest scores, particularly for color (4.98 ± 0.51). Noodles cooked with the 150 g CaO:75 mL H₂O combination were rated as acceptable and closely comparable to conventionally cooked noodles, indicating the sensory feasibility of the self-heating container concept, although further design refinements are warranted.