Olive oil was an extremely valuable commodity in ancient Rome. It has been estimated that “adult citizens going to public gymnasiums used as much as 55 liters (14.3 gallons) of olive oil annually for personal hygiene, for consumption, as a lubricant, for lighting, for rituals and as a medicament”. Roman citizens used so much oil that local output was insufficient.
Special ships were built to transport oil, and Hispania was the largest supplier.
Different uses. The fruit (bacca) of the olive was for the most part employed for one of two purposes.
1. It was eaten as a fruit, either fresh, pickled, or preserved in various ways.
2. It was pressed so as to yield the oil and other juices which it contained. And again, the oil was employed for a variety of purposes, but chiefly :
– As an article of food.
– For anointing the body, and in this case was frequently made a vehicle for perfumes (unguenta).
– For burning in lamps.
Preserving Olives (Condere oleas, olivarum conditura, conditio).
Olives might be preserved in various ways, either when unripe (albae, acerbae), or ripe (nigrae), or half-ripe (variae, fuscae).
Green olives, the Pausia being used principally for this purpose, were preserved in strong brine (muria), according to the modern practice, or they were beaten together into a mass, steeped in water which was frequently changed, then pressed and thrown with salt into a jar of vinegar, to which various spices or flavouring condiments were added, especially the seeds of the Pistachia Lentiscus, or Gum Mastich tree, and fennel. Sometimes, instead of vinegar, inspissated must (sapa, defrutum, or sweet wine (passum) or honey were employed, and sometimes salt pickle, vinegar, must and oil, seem to have been all mixed together.
Half-ripe olives (and here again the Pausia was the favourite) were picked with their stalks and covered over in a jar with the best oil. In this manner they retained the flavour of the fresh fruit for more than a year.
Ripe olives, especially the orchitis, were sprinkled with salt, and left untouched for five days, the salt was then shaken off, and they were dried in the sun. Or they were preserved sweet in defrutum without salt.
Oil making (Oleum conficere).
The fruit of the olive tree consists of two parts, the pulpy pericarp (caro), and the stone (nucleus).
The caro or pulp yielded two fluids: one of these of a watery consistence, dark in colour, bitter to the taste, flowed from the olive upon very slight pressure; it was called Amurca and was extensively used as a manure and for a great number of purposes connected with domestic economy.
The other fluid which flowed from the pulp, when subjected to more forcible pressure, was the oil (oleum, olivum), mingled however to a certain extent with amurca and other impurities (fraces, faeces), and this was of different qualities, according to the state of the fruit, and the amount of pressure.
The finest oil was made from the fruit before it was fully ripe, and from this circumstance, or from its greenish colour, was termed Oleum viride.
A distinction is made by Columella, between the oil obtained by the fruit when green (oleum acerbum s. aestivum), when half ripe (oleum viride), and when fully ripe (oleum maturum), and while he considers the manufacture of the first as inexpedient, in consequence of the scanty produce, he strongly recommends the proprietor to make as much as possible of the second, because the quantity yielded was considerable, and the price so high, as almost to double his receipts.
The gatherings of each day (coactura uniuscujusque diei) were kept separate, and great care was taken to leave them in this state for a very limited period, for if the masses heated, the oil soon became rancid.
If, therefore, circumstances did not allow of the oil being made soon after the fruit was gathered, the olives were spread out and exposed to the air so as to check any tendency towards decomposition.
Although both ancient and modern experience are upon the whole in favour of a slight fermentation, Cato, whose great practical knowledge entitles him to respect, strongly recommends that it should be altogether dispensed with, and affirms that the oil would be both more abundant in quantity and superior in quality: “Quam citissime conficies maxime expediet”.
The olives when considered to be in a proper state were placed in bags or flexible baskets (fiscis), and were then subjected to the action of a machine consisting partly of a bruising and partly of a squeezing apparatus. The oil as it issued forth was received in a leaden pot (cortina plumbea), placed in the cistern (lacus) below the press.
The oil was finally poured into jars (dolia olearia), which had been previously thoroughly cleaned and seasoned, and glazed with wax or gum to prevent absorption, the lids (opercula) were carefully secured.
After a moderate force had been applied to the press, and a considerable quantity of oil had flowed forth, the bruised cake (sampsa) was taken out of the bags, mixed with a little salt, replaced and subjected to the action of the press a second, and a third time. The oil first obtained (oleum primae pressurae) was the finest, and in proportion as additional force was applies by the press-men (factores, torcularii), the quality became gradually worse (longe melioris saporis quod minore vi preli quasi lixivium defluxerit).
Hence, the product of each pressing was kept distinct, the marketable value of each being very different (plurimum refert non miscere iterationes multoque minus tertiationem cum prima pressura). The lowest quality of all (oleum cibarium) was made from olives which had been partially damaged by vermin, or which had fallen from the trees in bad weather into the mud, so that it became necessary to wash them in warm water before they could be used.
L’huile sert à l’éclairage, aux massages dans les thermes et à l’alimentation.
Principale graisse d’assaisonnement et de cuisson, l’olive était l’objet de soins particuliers d’autant plus qu’elle ne donne de bonne récolte qu’un an sur deux.
Les olives étaient cueillies à la main, la chair broyée à la meule et ensuite malaxée pour favoriser la formation de gouttelettes d’huile; enfin, la pulpe était soumise à pression. On procédait ensuite à la décantation du mélange d’huile et de jus obtenu.
L’inestimable denrée était ensuite versée dans des dolia, immenses jarres en terre cuite, imperméabilisées à la gomme ou à la cire et scellées afin d’éviter que le contact de l’air ne la fasse rancir.
Les olives les plus grosses étaient bonnes à manger, donc mises en conserve; les plus petites étaient propres à fabriquer de l’huile. L’adjonction d’aromates non seulement les parfumaient mais contribuait à la conservation du produit. L’olive était un aliment en soi, présent dans l’alimentation de toutes les couches sociales; elle était utilisée telle quelle, arrosée d’huile ou parsemée d’herbes.
Les différentes huiles
• Oleum viride: c’est l’huile verte, pressée d’olives au seuil de leur maturité, en octobre. De rendement médiocre, elle ne se conservait pas longtemps mais son prix de vente était avantageux.
• Primum oleum: c’est la “première huile”, celle de novembre, lorsque les olives commencent à changer de couleur; de rendement bien supérieur à celui d’Oleum viride.
• Oleum: c’est l’huile d’olives mûres, la plus abondante et la plus courante; elle assaisonne les salades, conserve les aliments et enfin c’est celle qui permet de cuisiner.