Page:The Olive Its Culture in Theory and Practice.djvu/171

Rh The oil of the pulp is rich and of a delicious flavor, that of the stone is dark and cloudy, that of the seed contains essential oil, while the skin in its little cells contains an essential and resinous oil in small quantities. These oils of stone, seed and skin, far from adding to the oil of the pulp, would be a serious injury if not in such small quantities. From this it is obvious that in cultivating olives for oil, the varieties with much pulp and proportionately small seeds, should be selected, as is always done in the true oil countries. The proportion of oil to berry as given by reliable authorities runs from ten to twenty per cent. in weight. The Messrs Rae of Leghorn, olive oil exporters, in their pamphlet on the olive, give fourteen to twenty per cent. and eighteen to twenty for the finest oil varieties. Mr Cooper's best result as given, was ten and twelve per cent. Mr Ludovico Gaddi, and the agricultural manager at Santa Clara College, as well, estimate that forty pounds of berries will produce one gallon of oil, which is about eighteen per cent.; but this of course refers to well dried berries. It should be said that California olive culture is so comparatively recent and limited, that reliable statistics can hardly be expected. But it may be safely asserted that certain exaggerated statements which have appeared in print, as to percentage of oil to berries, will not be verified even in this exceptional soil and climate. In view of the fact that the processes of the oil mill, are singly to "extract" the oil, the clarifying, whether by simple deposit or by passing the oil through refining material, being but a part of the general work of separating the oil from the solid and watery parts of the berry, it is evident that unless some mechanical difficulty renders delay necessary or convenient, the berries will yield a better oil if this be extracted immediately or very soon after their gathering. That this is true is now admitted by all writers of value, and by all manufacturers of the fine grades of oil. The belief that olives retained for long periods in the store house produce as good an oil, and much more than the freshly worked—a belief held by the