Citrus fruits contain a variety of functional constituents. However, in some cases, the citrus flesh lacks certain functional constituents, such as nobiletin and auraptene. During juice extraction, nobiletin is extruded from the peel of ‘Shiikuwasha’ into the juice. As a result, nobiletin becomes available in the juice. The new Citrus-Ponciruss hybrid ‘Aurastar’ contains large quantities of auraptene in both the flesh and peel. Additionally, satsuma mandarin juice, enriched with β -cryptoxanthin, was produced by supplementation with an extract of its by-product. A simple, low-cost production process for isolating β -cryptoxanthin from by-products was also developed. Development of novel products containing functional constituents is significant for farmers and agribusiness.