6 



BULLETIlSr 803, U. S. DEPARTMENT OF AGRICULTURE. 



own system. The standards in Table 1, based on the best com- 

 mercial practice, have been suggested by Bioletti.^ 



Table 1. — Standards for size grades. 



Designation. 



Size. 



Average 

 diameter 



in six- 

 teenths of 

 an inch. 



Average number per pound. 



Mission. Sevillano. Ascolano. Manzanillo 



Extra large. 



Large 



Medium 



SmaU 



Extra small 



16 

 14 

 12 

 10 

 Below 9 



35 

 52 

 82 

 135 

 ? 



33 



49 

 78 

 142 

 ? 



148 

 ? 



39 



58 

 93 



160 



Many fancy names and symbols are used to designate the various 

 grades. The graded olives are sometimes run over sorting belts to 

 be segregated for color, but this is not common. 



After being graded and sorted, the olives are taken to the pickling 

 vats. In the newer factories, these are made of concrete, about 8 

 by 3 by 2 feet. Similar tanks of redwood are also used, and some- 

 times circular tanks of redwood, about 8 feet in diameter and from 

 4 to 5 feet deep. Subject to some variation, the following treatment 

 is applied: A quantity of 1| to 2 per cent caustic soda solution, in 

 weight about five times that of the olives, is poured over the fruit, 

 and allowed to stand for from 6 to 8 hours, with frequent stirring. 

 This liquor is then drained off, and the olives exposed to the air for 

 24 hours, with occasional stirring. More of the same or a weaker 

 solution is applied for a similar length of time, and again run off and 

 the fruit aerated. This operation is performed a third time, or until 

 the caustic reaches the pit, as indicated by a darkening of the flesh. 

 The lye solution is then run off, and fresh water added to the vat. 

 The water is changed about every 12 hours until all the lye is 

 washed out. The pickler determines this by taste. Tests of all 

 commercial samples analyzed, with phenolphthalein, show the ab- 

 sence of free alkali or normal carbonates. At this point, salting of 

 the olives is begun by soaking them in solutions of brine of gradually 

 increasing strengths, of about 1, 2, and 4 per cent of salt. Factory 

 control is by means of the salometer, a hydrometer graduated in 

 hundredths from zero in distilled water to 100 in saturated salt so- 

 lution. Usually the strongest solution employed is approximately 

 15° on this scale. The olives are soaked about 2 days in each of 

 these different solutions, after which they are canned in a 3 or 4 

 per cent brine and processed in a water bath. Recently Bioletti and 

 Cruess have proposed preserving in lacquered cans or glass jars with- 

 out any liquid.^ It is claimed that the olives thus treated keep their 

 black color better than when brine is used. 



^ Calif. Agr. Exp. Sta. Bui. 263. The California Olive Association recently has adopted 

 a set of size standards. 



2 Calif. Agr. Exp. Sta. Bui. 289. 



