2338 



OLIVE 



OLIVE 



Average olives are placed in a solution composed 

 of two ounces of potash lye to one gallon of water. They 

 are left in this solution from four to not more than 

 twelve hours. When the lye has penetrated nearly to the 

 pit as shown by a darkening of the flesh, the olives 

 should be removed to a bath of pure water. With very 

 bitter olives, a second treatment with lye is often 

 necessary. Stronger lye is likely to soften the fruit too 

 much. With very ripe or soft olives, it is necessary to 

 use salt from the beginning in the lye solution. Equal 

 quantities of salt and lye may be used and more time is 

 needed for neutralization owing to the hardening effect 

 of the salt. Some picklers prefer to use a 1 per cent 

 lye for all olives and to repeat the treatment two or 

 three times. The next step is to remove the excess of 

 lye from the olives. If the olives are firm, this is most 

 economically and rapidly accomplished by soaking in 

 pure water which is changed twice a day. If the olives 

 are soft, the water should contain 2 per cent of salt. 

 As soon as no taste of lye remains in the olives, they 

 are placed in a brine composed of four ounces of salt 

 to one gallon of water. This brine is replaced in about 

 two, seven and twenty-one days with brines of six, ten 

 and fourteen ounces to the gallon. This gradual increase 

 of the strength is necessary to prevent shrinkage and 

 shriveling of the olives. 



Great care should be taken not to allow the olives 

 to come in contact with anything that will injure their 

 flavor. The vats or other receptacles used for pickling 

 should be perfectly clean, odorless, and tasteless. Con- 

 crete is the best material, but wooden receptacles 

 thoroughly treated with boiling water and soda until 

 they are sterilized and all taste of the wood removed, 

 may be used. The vats should be provided with a 

 removable wooden grating, fastened 1 or 2 inches from 

 the bottom, and a close-fitting, floating wooden cover 

 to keep all olives submerged. Each vat should be pro- 

 vided at the bottom with a wooden spigot for drawing off 

 the solutions. The thickness of the layer of olives should 

 not be more than 2 feet, or less with soft varieties. 



In pickling green olives, when a light color is desirable, 

 the fruit should be exposed as little as possible to the 

 air, especially during the extraction of the bitterness. 

 In pickling ripe olives, on the contrary, when a uniform 

 dark color is desired, the action of the air is beneficial. 

 A great improvement in this respect can be obtained by 

 leaving the olives exposed to the air for twenty-four 

 hours when making the various changes of lye and salt 

 solutions. 



However carefully the processes of pickling are|carried 

 out, the olives will keep only for a limited time. They 

 usually remain in good condition for about six months 

 when kept in a strong brine, and the best may last in 

 fair condition for a few months longer. Few olives are 

 good when kept in the ordinary way for twelve months, 

 but by heating them in sealed cans or bottles, they can 

 be kept indefinitely with as great facility as any other 

 food-product. The heating does not injure the flavor 

 and the texture, but, on the contrary, improves them. 

 Olives preserved by heating do not require such strong 

 brine, and it is only necessary to add as much salt as 

 the palate requires. 



Olive oil. 



The best oil is made by working the olives as soon 

 as they are gathered, but it is usual to dry them partially 

 first to facilitate crushing and pressing. The drying is 

 accomplished by spreading the fruit in layers not over 

 3 inches deep on wooden trays which are spread out in 

 a well-aerated shed or loft. The olives must be turned 

 daily and prevented from molding. In cool, moist 

 weather this is very difficult, and artificial driers con- 

 structed on "the same principles as those for fruit and 

 hops are sometimes used. The heat of these driers 

 should be between 120 and 130 F. Higher tempera- 

 tures produce rancidity of the oil. Artificial drying 



requires about forty-eight hours; natural drying one 

 to two weeks. The dried olives may be stored in a cool, 

 dark, dry place for some time before crushing, but the 

 sooner they are used the better the oil, especially when 

 dried by artificial heat. 



The olives are first passed through a crusher con- 

 sisting usually of corrugated rollers which disinte- 

 grate the flesh without breaking the pits. The crushed 

 mass is then put under a press of moderate power. To 

 facilitate the escape of the oil and water, the crushed 

 olives are placed in layers of 3 to 4 inches, inclosed in 

 strong cloth and separated by gratings. After this 

 pressing, the pulp is thoroughly ground, usually with 

 the pits, in an "edge-runner" mill. The ground pulp 



is then pressed 

 a second time. 

 The second 

 pressing requires 

 a very powerful 

 press and very 

 strong cloth to 

 contain the pulp. 

 The first press- 

 ing may be 

 omitted when 

 the olives are 

 dried. 



The liquid 

 which comes 

 from the press 

 contains oil, 

 water and vari- 

 ous impurities 

 both solid and 

 dissolved in the 

 water. If al- 

 lowed to stand, 

 the oil, owing to 

 its light specific 

 gravity, will 

 come to the top 

 and may be 

 skimmed off and 

 freed from float- 

 ing solid matters 

 by screening. 

 The separation, 

 however, is very- 

 slow and imperfect and is facilitated by the process 

 known as "washing." There are various devices for this 

 purpose but they all consist in mixing the press liquids 

 with a stream of pure water with continued gentle 

 agitation. Some of the devices are continuous and the 

 oil rising to the top flows off into the oil vats and the 

 water and impurities escape at the bottom. 



The oil thus obtained is more or less cloudy owing to 

 the presence of minute particles of solid matter and 

 must be made perfectly bright before it is merchantable. 

 Perfect clarification of the oil may be accomplished by 

 several successive settlings and decantations. The set- 

 tling vats may be of tin or concrete. Drawing off after 

 a settling of twenty-four to forty-eight hours removes 

 most of the solid matter. The remainder is removed by 

 two or three drawings-off , each after a settling of about 

 a month. Filtration is usually used to hasten clarifica- 

 tion. The most commonly used filtering materials are 

 cotton, pure sand and filter paper. Filtering must be 

 practised with moderation as it tends to diminish the 

 flavor. 



Only 50 per cent to 65 per cent of the oil is recov- 

 ered by the methods now in use in California. The 

 pulp with the retained oil is wasted or used as pig feed. 

 A somewhat large percentage of the oil can be recov- 

 ered by means of a centrifugal machine and the trouble- 

 some pressing and press cloths done away with. This 

 method, however, has never been adapted to an indus- 



2576. Varieties of olive. 1, Ascolano; 2, 

 Sevillano; 3, Manzanillo; 4, Mission; 5, 

 Nevadillo; 6, Frantoio; 7, Redding. (X 

 about ). 



