748 EXPERIMENT STATION RECOED. 



Eleven iinheated samples kept in a fair to good condition for 11 months, but they 

 were all more or less spoiled within 32 months. Twenty samples heated to 80° C. 

 kept perfectly for 32 months, at the end of which time they were as good as when 

 made, with the exception of one sample which deteriorated slightly. 



"It may be concluded from this that heating to 80° C. (176° F.) is a sufficient 

 means of preserving ripe olives, even in weak brine, for an indefinite period in 

 hermetically sealed glass jars, provided that they are exposed to no greater changes 

 of temperature than occur in an ordinary room in Berkeley. . . . There is every 

 reason to believe that a slightly higher heating, say to 90 or 95° C, would have 

 made them perfectly secure in any climate. . . . The only objection to heating 

 noted was that it causes a diffusion of the coloring matter of the olives into the brine, 

 so that after heating the olives were lighter-colored and the brine darker than before. 

 This diffusion, however, takes place in time even with unheated olives, and at the 

 end of 32 months the unheated olives were in most cases actually lighter-colored 

 than those which had been heated." 



The results of the test indicate that Gordal, Manzanillo, Columbella, and Regalis 

 are the best varieties for home use; and that Sevillano, Mission, Picholine, Manzanillo, 

 and Gordal are most satisfactorj' for market purposes. 



Exper-iments in pickling green ol ires (pp. 13-21). — Experiments have been made to 

 determine the best methods of pickling green olives so as to preserve the green color. 

 None of the usual methods of treating ripe olives, either with comparatively strong 

 lye for short periods or with weaker lye for a longer period, was successful and in 

 pure running water the olives turned brown the quickest. This fact suggested that 

 possibly the oxygen in the air dissolved in the water might be a factor in the discolora- 

 tion. Further experiments were therefore made with weak lye solutions which had 

 been boiled to expel the air. The olives were kept in the lye solution until their 

 bitterness was neutralized. With the weaker solutions it was found necessary to 

 renew the lye several times. After neutralization they w^ere pickled with salt solu- 

 tions of gradually increasing strength as with ripe olives. By this treatment it was 

 found possible to produce green olives which retained their color for 12 months. It 

 is necessary first to find the proper strength of the lye solution to use for the variety 

 or grade of olives to be pickled. This may be done by using a series of pint fruit- 

 preserving jars containing the olives. In these should be poured different strength 

 lye solutions beginning with j per cent and increasing by 2 per cent to 3 per cent 

 solutions. When a solution is found just a little stronger than is necessary to 

 neutralize the bitter principle in the olives in 48 hours, this strength should be chosen 

 for curing the bulk of the crop. The proper strength having l)een determined, it is 

 recommended that the olives be placed in a 50 gal. barrel having a 4 or 5 in. bung- 

 hole and covered with lye. After soaking 48 hours the lye should be drawn off, the 

 olives washed quickly with 2 changes of fresh water, and covered immediately with 

 a 2 per cent brine solution. This should be rei)laced successively by 4 and 8 i>er 

 cent solutions, allowing each solution to remain from 48 to 72 hours, depending on 

 the size of the olives, and finally by a 12 per cent solution. 



"The essential part of the process is to avoid exposing the olives to the air during 

 the pickling, until all the bitterness and acid are completely neutralized by the lye. 

 After this the green color seems to be fixed, and exposure to the air does not change 

 it much, though it is well, all through the process, to avoid leaving the olives 

 uncovered by liquid any longer than necessary. 



"As different varieties of olives and even the same variety in different seasons and 

 from different localities differ very much in bitterness, the importance of treating 

 each variety separately is evident, as each will require lye solutions of different 

 strength to neutralize them. Very bitter olives, such as Mission, Sevillano, Manza- 

 nillo, and True Picholine, require solutions containing from H to 2i per cent of pure 

 potash lye, while olives containing little bitterness, such as Ascolano and Colum- 



