AGRICULTURAL CHEMISTRY AGROTECHNY. 209 



"The benefits to be obtained from the nse of pure yeast are more complete 

 elimination of the sugar, as indicated in the table of analysis and higher quality 

 of flavor and appearance, which were noticeable." 



A new method of handling the distillation residues of wines, Camille 

 Matignon {Chem. Ztg., 38 (1914), No. 36, pp. 386, 387).— A description of the 

 EfEront fermentation process for the utilization of wine distillation residues for 

 the preparation of organic bases, cyanids, acids (acetic, butyric, etc.), and 

 glycerin. 



Bitter principles of olives, F. T. Bioletti (California 8ta. Rpt. 191 Jf. pp. 

 197-199). — In the preparation of either green or ripe olives for food one of the 

 points taken into consideration is the removal of the bitterness. This is accom- 

 plished by prolonged soaking in water, by treatment with a caustic alkali (or 

 lye) solution, or by a combination of both. As the exact nature of the sub- 

 stances to which the bitterness is due does not seem to be well understood, nor 

 the effect on the principles by the various pickling operations, a series of tests 

 was made for the purpose of throwing some light on these points. 



The bitter principles are soluble in water, hot alcohol, and chloroform, and 

 slightly soluble in ether. In crushing olives, some of the bitterness comes out 

 with the juice and some remains in the pulp. The bitterness of olives is not 

 discharged by exact neutralization, by the presence of a slight excess of alkali, 

 by exact neutralization and heating under 15 lbs. pressure for one hour, by a 

 slight excess of hydrochloric acid and heating under pressure, by heating un- 

 treated juice under pressure, the presence of an excess of sodium bicarbonate, 

 or by fermentation with yeast. It is destroyed by using a considerable excess 

 of either sodium hydroxid or sodium carbonate, or a slight excess of alkali and 

 heating under pressure. The tests on juice alone indicated that a 2 per cent 

 potassium hydroxid solution will destroy the bitterness immediately, and neu- 

 tralization and the addition of a 0.7 per cent excess of potassium hydroxid 

 within 24 hours. Adding an excess of 0.56 per cent of alkali had little effect. 

 Owing to the resistance of the tissues of the olive to the passage of water the 

 bitter principles are not so readily removed by water alone. The resistance may 

 be diminished by soaking the olives in water containing caustic potash or soda, 

 and these when used in excess will hydrolize oleuropeine, a glucosid which ap- 

 pears to be the cause of the bitterness. 



Softening- of olives, F. T. Bioletti {California l^ta. Rpt. Wlff, pp. 199, 200).— 

 " Certain varieties of olives, and all when overripe, tend to become soft during 

 the pickling processes, especially in the lye solutions. Salt may be used in 

 conjunction with the lye to counteract this softening effect." Tests made to 

 determine the proper amount of salt to use resulted in showing that 3 per cent 

 appears to be suitable and sufficient even with strong lye solutions. 



Sizing of pickled olives, F. T. Bioletti (California Sta. Rpt. 1914, pp. 200, 

 201). — Determinations of the sizes — i. e., average diameters and corresponding 

 number of olives per pound — were made on a number of commercial samples of 

 pickled olives. The variations in each size were found to differ very much 

 with different brands of olives, the differences depending probably on the kind 

 of sizing machine employed. 



Tables giving the results of the measurements are presented. 



Olive paste, F. T. Bioletti (California Sta. Rpt. 1914, p. 200). — Certain 

 varieties of olives, and a certain proportion of even the largest varieties, are 

 too small to satisfy the popular demand for a large pickled fruit. The small 

 fruits are used for the manufacture of oil, but their value for this purpose is 

 small, although when pickled they equal or exceed the large olives in flavor. 



