Development and Physicochemical and Sensory Evaluation of Ginger and Turmeric Spiced Tofu as a Value-Added Soy-Based Product

The increasing need for affordable, plant-based protein sources has driven interest in developing value-added soybean products. Tofu, a soy-based product derived from Glycine max, is a protein-rich food containing essential nutrients; however, its consumption in Ethiopia remains limited due to low consumer awareness and sensory factors such as its mild flavor and pale color. This study was conducted to develop spiced tofu by incorporating ginger (Zingiber officinale) and turmeric (Curcuma longa), and to assess its sensory and physicochemical characteristics. A laboratory-based experimental design was employed, where tofu samples were prepared with varying inclusion levels (5%, 10%, and 15%) of ginger and turmeric in a 1:1 proportion, along with an unspiced control. Physicochemical parameters, including moisture content, ash content, and pH, were analyzed using standard methods. Sensory attributes such as color, aroma, taste, texture, and overall acceptability were evaluated by semi-trained panelists using a nine-point hedonic scale. Data were analyzed using one-way ANOVA followed by Tukey’s HSD test (p < 0.05). Results indicated that spice incorporation slightly decreased moisture content while increasing ash content, indicating a potential increase in mineral content. A minor reduction in pH was also observed, though values remained within acceptable ranges. Sensory evaluation showed that tofu with a moderate spice level (10%) received significantly higher scores across all attributes compared to the control, whereas higher levels (15%) reduced acceptability due to overly strong flavor. In conclusion, incorporating ginger and turmeric at optimal levels enhances the sensory quality of tofu without adversely affecting its physicochemical properties, and offers potential for developing culturally acceptable, value-added tofu products in Ethiopia.