Distilled Lime Oil

#### Lime Oil, distilled. Out of an annual world production of more than 400 metric tons of **Lime**** ****Oils**, the major part by far is **Distilled Lime Oil**. There are two ways of producing a distilled lime oil: - By steam distillation of the crushed or comminuted peels, - By distillation of the acid juice from the lime fruit presses. This juice will separate into three layers during a 2-4-week storage period in wooden tanks. The middle layer is lime juice and will usually be concentrated and canned. The upper layer is good juice, pulp and lime oil. The lower layer also contains some partly dissolved lime oil. This mixture is steam distilled cautiously, and the oil in the receiver is separated. During the evaporation of the good lime juice, significant amounts of lime oil are separated, and this oil is mixed with the steam distilled oil. Obviously, the treatment in boiling water of high acidity has a pronounced effect upon the flavor of the delicate essential oil, but, surprisingly enough, most people prefer the distilled lime oil over the (hand or machine) expressed one because of its "greater similarity to natural lime flavor". Thus, the distilled lime oil is by far the most important of the lime oils. **Distilled Lime Oil **is a pale yellow or almost water-white mobile liquid of sharp, fresh, terpenelike, somewhat perfumery-fruity citrus-type odor. The oil is very volatile (poor tenacity), but shows increasing sweetness on drying out, the notes becoming more orange- like, less lemon-like. As pointed out above, the general impression is that the odor of this oil is very reminiscent of the odor of fresh limes when they are halved and squeezed. In the author's opinion, however, the odor of distilled lime oil is considerably more "paint-can- like" or harsh-terpeney than that of the scratched peel of a green lime fruit. But when a halved lime fruit is squeezed in the preparation of limeade, the very acid juice is flavored with squirts from the peel; this mixture of acid juice and peel oil has a flavor very different from that of the oil alone. The most modern method developed so far for the production of distilled lime oil uses super-heated steam and vacuum simultaneously; thus it is possible to distil halved, juice-exhausted fruits directly without adding water and at a comparatively low temperature. However, the conventional method of distilling the expressed juice from the whole fruit is still the most economical method: it requires less complicated equipment, and the operation itself requires less skill or technical knowhow. A general description of **Distilled Lime Oil **would be rather superficial since there are numerous types and qualities on the market. For flavor use, a thorough evaluation of the flavor in the end product is recommended. There is a distinct difference between the oils distilled from the acid juice and those distilled from the juiceless, chipped peels. The flavor quality of lime oil is dependant upon the content of so-called oxygenated constituents (as distinguished from the hydrocarbons = terpenes which form the bulk of the oil). Citral and some of the aliphatic aldehydes (C-8 to C-10), linalool, geraniol, terpineol, borneol and their esters supply the characteristic notes. The freshness, however, is undoubtedly due partly to the terpenes, among which limonene and natural dipentene actually have pleasant odors. Needless to say that if the oil is not fresh and if the terpenes are perceptibly decomposed or oxidized, the oil is worthless no matter how good the oxygenated components are. It seems that methyl anthranilate is found in expressed lime oil only (see the following monograph). **Distilled Lime Oil **is used as a flavoring agent in soft drinks, candy and many kinds of food products. Terpeneless and sesquiterpeneless lime oil (see this monograph) is preferred for soft drinks for its superior solubility and stability. The **Cola**- type of carbonated beverages probably absorb the majority of all lime oils. The suggested use level of **Distilled**** ****Lime Oil **is 1.00 to 8.00 mg%, and the **Minimum Perceptible **is about 0.30 to 0.60 mg%. In perfumes, the **Expressed**** ****Lime**** ****Oil**** **is often preferred since the terpeney note of the distilled oil is a note rarely wanted in perfumery. The peculiar freshness of the expressed oil has a unique effect in certain types of colognes, chypres, etc. See monographs of **Lime**** ****Oil,**** ****Expressed**** **and **Lime**** ****Oil,**** ****Terpeneless**** **and **Sesquiterpeneless.**