Comparative physical examination of various citrus peel essential oils

Abstract

Physical parameters of various citrus peel essential oils were determined in this study. Essential oils from the peels of Kinnow (C. reticulata, var. mandarin), Fewtrell's early (C. reticulata, var. tangerine), Malta (C. sinensis var. malta), Mousami (C. sinensis var. mousami), grape fruit (C. paradisi) and eureka lemon (C. limon) were extracted by applying cold expressing method. Eureka lemon had the highest peel portion i.e. 45.0%. Similarly, Malta peel had the highest oil yield i.e. 1.21%. Physical evaluation of oils delineated that Fewtrell’s early peel oil had the lowest specific gravity i.e. 0.841, whereas, highest refractive index and optical rotation were found in Grape fruit (1.472) and Malta (93.257) oils. Similarly, the lowest evaporation residue (3.122%) has been observed in Grape fruit peel oil. All the essential oils were found soluble in different ratios, ranging from slight haziness to clearly soluble in 95% alcohol. Flavor of these oils was also evaluated through olfactory method. Eureka lemon and Mousami peel oils had the pleasant sharp and strongest flavor followed by kinnow, Fewtrell’s early, Malta and Grape fruit.