"O IL is obtained from seeds of various sorts and from certain kinds of fruit, but the most highly esteemed oil for the table, the very queen of oils, is that which we get from the olive, the fruit of the olive-tree. This precious tree, which the ancients made the symbol of peace, fears the rude winters of the North and thrives with us only in Provence and Langue-doc, especially in the departments bordering on or near the Mediterranean. In size it is not a tall tree, usually attaining about twice the height of a man. Its head is rounded, not very dense in growth, and furnishing but poor shade; its leaves are narrow, leathery, of an ashen-green color, and do not fall in winter. In summer its sparse branches are the favorite resort of grasshoppers, which, reposing on the bark of the tree in luxurious exposure to the intense heat of the sun, indulge in unrestrained exhibition of their musical accomplishments.
"The olive is green at first. The flesh covering its hard stone, which is pointed at both ends, has the most disagreeable taste you can imagine. An unripe grape is sour, an immature pear harsh, a green apple tart; but an olive not yet fully ripened far surpasses them all in repulsive flavor. At the very first bite its unbearable acridity burns the mouth so that you might think you were chewing a red-hot coal. Certainly he had need of a rare inspiration who first reposed confidence in this unpleasant fruit and succeeded in extracting its oil, which is mildness itself."
"I once took a notion," said Marie, "to taste of an olive as it grew on the tree, and I can tell you I soon had enough of it. Goodness, what a horrid fruit! How can such sweet oil come from such bitter flesh?"
"Later when the cold weather of approaching winter comes, in November and December, olives change from green to reddish, and finally turn black. Then the skin wrinkles and the flesh ripens, losing its tartness and becoming rich in oil. That is the time for harvesting the fruit. Women with the help of short ladders gather it by hand and fill their upturned aprons, blowing now and then on their fingers, benumbed by the piercing cold of the December mornings. The harvest is piled up at the foot of the olive-tree on a cloth that has been spread there, and the picking is resumed amid interminable chattering and bursts of laughter from among the branches.
"The olives are taken to the mill, where, after being crushed under vertical millstones, they are cold-pressed. By this first pressure is obtained fine or pure oil, the most esteemed of all. Subjected to the action of hot water and pressed a second time, olives furnish a second grade of oil. Finally the residue, mixed with the imperfect olives, such as windfalls and those that are worm-eaten, yields what is known as pyrene oil, which is too ill-flavored to be used in cooking, but is useful for lighting and for soap-making. The very last residue is made into oil-cakes, an excellent fuel."
"But it isn't their oil alone that makes olives valuable," said Marie; "they are good to eat after some sort of treatment that I should like to know more about."
"Olives that are black, very ripe, and wrinkled, can at a pinch be eaten just as they come from the tree, in spite of a slight harshness of flavor that still clings to them. To remove this they are slightly salted, sprinkled with a few drops of oil, and kept in a pot, where they are stirred from time to time. In a few days they are ready to eat. Sometimes they are merely soaked in salt water.
"But however they may be prepared, black olives are never equal to green ones. The most ill-flavored olives as they hang on the tree are the best when once freed of their extremely disagreeable taste. Energetic treatment is necessary to give them the desired mildness of flavor. Recourse is had to potash, that harsh substance I told you about in speaking of ashes and the use of lye in washing. A quantity of very clean ashes is taken from the fireplace and put into water, to which is added a little lime, the effect of which is to increase the strength of the potash. Finally the clear liquid, charged with the soluble portion of the ashes, is poured over the green olives. After some hours of contact with this corrosive fluid they lose their acridity, and all that remains to be done is to rid them of the lye that impregnates them. This is accomplished by soaking them in pure water and changing the water every day until it is colorless and tasteless. By this repeated soaking nothing that the ashes had contributed is left. Lastly the olives, now a beautifully green color and an agreeable taste, are salted down in brine, which insures their preservation and corrects any undue sweetness of flavor."
"Then it is potash," said Claire, "that turns the horrid-tasting fruit into the olives we see on the table, and that I am so fond of."
"Yes, it is the potash obtained from ashes, potash alone, that subdues and softens the harsh flavor of the olive. Add this service to those that the same substance renders us when it enters into the composition of soap, glass, and washing-fluid.
"In the case of the olive it is the flesh of the fruit that furnishes the oil; but other forms of vegetation valued for their oily constituent have this in their seeds, their kernels. Leading examples are the walnut, sesame, poppy, colza, a kind of turnip called rape, and flax. Break a dry walnut, take a quarter of the meat, and hold it close to the flame of a lamp. You will see it catch fire and burn with a beautiful white flame which feeds on an oily juice that oozes out as the heat increases. Thus we find there is oil in walnuts. To extract it, we crack the nuts and take out the meats, which we subject to strong pressure. Freshly made nut-oil is pleasant to the taste and well adapted to culinary purposes; therefore it is much in demand wherever nuts abound. Unfortunately, it soon turns rancid and it contracts with age a strong and exceedingly repulsive taste.
Flowering Branch of Walnut Tree, with Fruit
"Sesame is an herbaceous annual cultivated chiefly in America and Egypt. Its seeds furnish a sweet oil having nearly the same qualities as olive-oil. Sesame-oil is not sold as such with us, but I suspect dealers occasionally mix it with olive-oil, which is much more expensive.
"Poppy-heads are full of very fine seeds which furnish a fairly good oil known as poppy-oil."
"Poppy-heads will put a person to sleep," observed Claire. "I remember once somebody made me drink some poppy-tea to put me to sleep when I was ill. Poppy-oil ought to make one sleep too."
"It is perfectly true that poppy-heads make a tea that induces a deep sleep. They owe this property to a substance called opium, which is so powerful that if you took a dose of it no bigger than a pea it would act as a deadly poison and put you to sleep forever. But this formidable substance is found only in the shell of the fruit, in the envelop of the poppy-head, and not in the seeds. Hence the oil extracted from these seeds can be used in cooking without any danger.
"Colza and rape are two varieties of turnip cultivated principally in the North. The pod-like fruit contains two rows of fine seeds under two long strips or valves that open from bottom to top at maturity. These seeds give colza-oil and rapeseed-oil, which are used for lighting and also in some of the industrial arts, but are unsuitable for cooking on account of their offensive taste.
"Linseed-oil, finally, which is used chiefly in painting, I have already told you about in one of our former talks."