Orange Oil, Bitter, concentrated

#### Orange Oil, Bitter, concentrated. For use in flavors, particularly in liqueurs and carbonated beverages, the natural oil of bitter orange offers some disadvantage because of its high content of monoterpenes (over 90%). The monoterpenes produce unpleasant off-flavors (with weak alcohol), and they are not soluble in low-proof alcohol, let alone in water. Many larger consumers of bitter orange oil for flavors will produce their own concentrates according to their special needs. A so-called *ten-fold** ***Bitter Orange Oil **is quite common, and offers a "happy medium" between the terpeneless-sesquiterpeneless oil on one side and the natural oil on the other side. Ten-fold bitter orange oils are commercially available. Concentration can be obtained by vacuum distillation, or by a combination of vacuum distillation and extraction with weak alcohol (see chapter on **Terpeneless Oils**, Part One of this book, and **Lemon Oil**, **terpeneless **in Part Two of this book). It is also possible to vacuum-concentrate the oil to about one-tenth of the original weight. chill the residual oil, freeze out the waxes, filtrate the concentrated oil and extract the wax with weak ethyl alcohol. After evaporation of the alcohol (and water), this extract is added to the concentrated oil. The resulting mixture is adjusted to a certain concentration (according to special requirements by the manufacturer or the user) by the addition of selected fractions of oil from the vacuum distillation. This concentrated oil is dark orange or yellowish-brown, but it is soluble in 70% ethyl alcohol in the proportions most often required. Complete deterpenation (see **Lemon Oil, terpeneless**) produces an almost water-white oil. Terpeneless, Sesquiterpeneless **Bitter**** ****Orange**** ****Oil**** **is an extremely powerful flavor material, and its good stability makes it useful in all kinds of aqueous foods, candies, beverages, liqueurs, etc. It represents only about 3% by weight of the natural oil, but it is not 33 times stronger in flavor effect. The "lift" from the monoterpenes and their refreshing topnotes are effects which are lost in the terpeneless oils. However, the concentrated (e.g. ten-fold). partially deterpenated oils are much more popular and almost equally stable flavor materials.