Characterization of flavor quality in sago starch produced by different processing methods: Insights from physicochemical, metabolomic, and sensory analyses.

Sago is a high-carbohydrate, naturally gluten-free product derived from tropical palm trees, serving as an essential staple food in many regions of Southeast Asia and the Pacific Islands. The various processing methods used to produce sago starch can influence its overall quality, including its flavor. To date, a comprehensive analysis of its flavor quality across different processing methods has not yet been conducted. This study aimed to characterize the flavor quality of sago starch by combining physicochemical, metabolomic, and sensory analyses. Sago starch samples produced using traditional, semi-mechanized, and modern methods were collected and analyzed. Principal component and heatmap analyses revealed that traditional processing resulted in lower sensory and physicochemical quality, characterized by higher off-flavor compounds, particularly organic acids, likely due to uncontrolled microbial activity. In contrast, modern processing yielded higher levels of sugars such as sucrose and fructose, associated with desirable flavor, while semi-mechanized processing produced intermediate flavor profiles, possibly due to partial fermentation. Partial least squares regression analysis identified potential key metabolites related to flavor deterioration in sago starch, including octanoic acid, 3-methylbutyric acid, and hexanal. These findings can support improvements in sago starch processing to enhance flavor quality and guide quality control strategies in the industry.