Perilla frutescens var. crispa (Red Shiso) is a cultivated variety of the herbaceous plant Perilla frutescens in the mint family, Lamiaceae, distinguished by its deep red to purple foliage and strong aromatic profile. The species name frutescens comes from Latin, meaning “becoming shrubby,” reflecting its bushy growth habit, while the varietal epithet crispa means “curled” or “wavy,” describing the leaf margin texture. The common name “shiso” (紫蘇) derives from Japanese, where it originally referred to purple-leaved perilla, emphasizing its traditional culinary and medicinal significance in East Asia.

Red shiso is primarily associated with Japan, where it has been cultivated for centuries, though related varieties are also found in China and Korea, and it has influenced regional herb usage throughout East Asia. As a food source, red shiso leaves are used both fresh and processed. Fresh leaves serve as a garnish, flavoring for rice, salads, and pickled dishes, while the leaves are also commonly used to impart color and flavor to umeboshi (pickled plums), vinegar, jams, and beverages. Its pigments, anthocyanins, provide the distinctive red-purple color and act as natural antioxidants. Red shiso has also been valued in traditional medicine for its aromatic and anti-inflammatory properties.

Chemically, red shiso contains a rich profile of bioactive compounds, including rosmarinic acid, luteolin, apigenin, perillaldehyde, and anthocyanins such as shisonin, which are responsible for the red coloration. These compounds contribute antioxidant, anti-inflammatory, and antimicrobial effects, making red shiso both a culinary and functional plant. The leaves are aromatic due to essential oils dominated by perillaldehyde, which is heat-sensitive and partially volatile during cooking, while anthocyanins are moderately heat-stable and provide both color and potential health benefits.