This study explored how enzyme type (cellulase and pectinase), concentration, and mixing ratio influence the functional compounds and antioxidant activities of purple sweet potato (Ipomoea batatas L.). The enzyme treatment significantly impacted all measured parameters. At a cellulase concentration of 30 units, the total anthocyanin content reached 399.4 mg/100g dry weight (DW), representing a 163% increase compared to the control (151.6 mg/100g DW). Total polyphenol (1,799.7 mg GAE/100g DW) and flavonoid (475.3 mg CE/100g DW) contents also peaked under these conditions, while higher enzyme concentrations or increased pectinase ratios reduced extraction efficiency. The highest ABTS radical scavenging activity was noted at 30 units of cellulase (954.0 mg TE/100g DW) and at 80 units in a combined treatment of cellulase (2) to pectinase (1) (927.2 mg TE/100g DW), suggesting that moderate enzyme synergy enhances antioxidant release. Conversely, DPPH activity decreased with higher enzyme concentrations, with all combined treatments yielding lower results than the control. Overall, the optimal condition for enhancing both functional compound extraction and antioxidant activity in purple sweet potato was identified as a single treatment with cellulase at 30 units.

This study optimized the extraction of β-carotene and antioxidant compounds from orange-fleshed sweet potato (Ipomoea batatas L.) using response surface methodology (RSM) with ethyl lactate as a green solvent. A central composite design (CCD) was utilized to evaluate how the solvent-to-sample ratio, temperature, and extraction time affected efficiency. The regression model was statistically significant (Adj. R2=0.67), revealing that the solvent-to-sample ratio was the most influential factor, while temperature and time had relatively minor effects. The optimal conditions identified were a ratio of 12 mL/g, a temperature of 35°C, and an extraction time of 30 minutes, which resulted in a yield of 27 mg/100g of β-carotene, along with high levels of polyphenols, flavonoids, and strong antioxidant activities as measured by DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline- 6-sulfonic acid)) assays. Validation experiments demonstrated a close alignment between predicted and experimental values, confirming the model's robustness. These findings indicate that ethyl lactate effectively extracts not only carotenoids but also a wide range of antioxidants, underscoring its potential as a sustainable solvent for developing functional food ingredients.

This study assessed the processing suitability and functional potential of sweet potato paste by comparing quality characteristics across different cultivars and heat treatment methods (steaming and baking). Generally, moisture content was higher after steaming, with the ‘Bodami’ and ‘Pungwonmi’ cultivars retaining more moisture, while ‘Jinyulmi’ and ‘Danjami’ had lower moisture levels. Purple-fleshed cultivars displayed negative a* and b* values, indicating bluish hues, whereas yellow-fleshed cultivars maintained stable b* values after heating. Both °Brix and free sugar levels increased after treatment, with baking significantly elevating maltose levels and enhancing sweetness. Apparent viscosity was higher in ‘Danjami’, ‘Jinyulmi’, and ‘Bodami’, while ‘Hogammi’, ‘Hopungmi’, and ‘Sodammi’ exhibited lower viscosity. Additionally, ‘Bodami’ and ‘Danjami’ demonstrated the highest levels of polyphenols, flavonoids, and antioxidant activities, confirming their potential as valuable functional ingredients. These findings underscore the importance of selecting appropriate cultivars and heat treatments to optimize the physicochemical and functional qualities of sweet potato paste.

This study assessed dried vegetables derived from sweet potato petioles to promote the use of typically discarded aerial parts. The length (18.25 to 35.00 cm) and thickness (4.59 to 6.66 mm) of the petioles varied by variety, with ‘Hophungmi’ and ‘Tongchaeru’ showing promise for dried vegetable processing due to their longer and thicker petioles. In terms of color, ‘Hophungmi’ and ‘Shinmi’ exhibited high lightness, ‘Tongchaeru’ and ‘Hayangmi’ displayed strong redness, and ‘Pungwonmi’ had high yellowness. Rehydration rates and hardness increased over the harvest period, with ‘Pungwonmi’ and ‘Tongchaeru’ demonstrating excellent rehydration capacity. Additionally, ‘Hayangmi,’ ‘Shinmi,’ ‘Tongchaeru,’ and ‘Hophungmi’ maintained lower hardness levels, appealing to consumers who prefer a softer texture. Notably, the substantial polyphenol content (10.70 to 16.20 mg GAE/g) and flavonoid content (4.79 to 8.11 mg CE/g), along with antioxidant activity (DPPH: 1.11 to 2.14 mg, ABTS: 5.51 to 7.78 mg TE/g), indicate their potential as antioxidant-rich functional foods. This research supports the development of dried vegetable products tailored to consumer preferences.