This study shows that phenolic compounds from potato peel were
successfully extracted using subcritical water. Temperature and time
affected the extraction of phenolic compounds from potato peel. The
results also demonstrated that extraction yield increases as the
temperature increases as a result of increased solubility of phenolics
in water. In addition, higher content of gallic acid was extracted using
subcritical water compared to methanol or ethanol. The subcritical
water extraction of phenolic compounds were maximized at 180 °C
and 60 min. Above 180 °C, degradation of phenolic compounds
occurred. Subcritical water removed high amounts of phenolic
compounds from potato peels in shorter time and required about
50% less solvent (160 mL) than with methanol or ethanol extraction
(300 mL). Furthermore, by using subcritical water, it is possible to
extract different types of free and bound form phenolics from potato
peel. These compounds could be used in the food and nutraceutical
industries.