Theessential oilof kumquat peel contains much of the aroma of the fruit, and is composed principally oflimonene, which makes up around 93% of the total.Besides limonene andalpha pinene(0.34%), bothmonoterpenes, the oil is unusually rich (0.38% total) insesquiterpenessuch as ? bergamotene(0.021%),caryophyllene(0.18%), ? humulene(0.07%) and ? muurolene(0.06%), and these contribute to the spicy and woody flavor of the fruit.Carbonylcompounds make up much of the remainder, and these are responsible for much of the distinctive flavor. These compounds includeesterssuch asisopropyl propanoate(1.8%) andterpinyl acetate(1.26%);ketonessuch ascarvone(0.175%); and a range ofaldehydessuch ascitronellal(0.6%) and2 methylundecanal. Other oxygenated compounds includenerol(0.22%) and trans linalool oxide(0.15%).