1920] AGRICULTURAL, CHEMISTRY AGROTECHNY. 807 



Experimental data are reported indicating that tlie application of a vacuum 

 as described above is preferable to heating as a means of deaerating the molasses. 

 The individual accidental error in the density determination of molasses with 

 this apparatus is shown to be within 0.1° Brix and, therefore, considerably 

 less than hitherto atttainable. 



Factors determining the keeping quality of cane sugar, N. and L. Kope- 

 LOFK (Louisiana Stax. Bnl. fiO (1U20), pp. S-63, fig. 1). — This bulletin includes 

 the reports of a series of investigations on the deterioration of sugar by molds. 

 Mo.st of these studies have been previously noted from other sources as follows : 

 (1) Do Mold Spores Contain Enzyms? (E. S. R.. 42, p. 336) ; (2) The Invertase 

 Activity of Mold Spores as Affected by Concentration and Amount of Inoculum 

 (E. S. R., 42, p. 803) ; (3) The Effect of Concentration on the Deteriorative 

 Activity of Mold Spores in Sugar (E. S. R., 42, p. 803) ; and (4) Effect of Vary- 

 ing the Amount of Inoculum and Concentration on the Deterioration of Sugar 

 by Molds (E. S. R.. 43, p. 507). 



The general conclusions drawn in the above studies are summarized in part 

 5, entitled The Present Status of the Problem of Sugar Deterioration. In this 

 iittention is also called to the recently reported determinations by Kopeloflf 

 and Perkins of the deterioration of Cuban raw .sugars in storage (E. S. R., 43, 

 p. 616), and a chart is presented by means of which it is possible to predict the 

 keeping quality of sugar from the standpoint of infection by molds. In this 

 chart moisture ratios are plotted as abscissas and mold spores per gram as 

 ordinates. The fields in which no deterioration, slight deterioration, and 

 marked deterioration may be expected are appropriately differentiated. 



[Cider investigations], O. Grove {Univ. Bristol, Ann. Rpt. Agr. and Hort. 

 Research Sta., 1919, pp. l.'t-22; also in Jour. Bath and West and South. Counties 

 Soc.. 5. ser., llf (1919-20), p. 106-llS). — Experimental studies on cider making 

 (luring the year 1918-19 are reported in the following papers: 



Cider making experiments for the season. 1918-19. — As a means of increasing 

 the output of cider in seasons of scarcity and high prices of fruit, the following 

 method was tested : 



After pressing the apples in the usual way the pressed pomace was broken 

 up and mixed in an open vessel with enough cold water to cover. After soak- 

 ing lor 24 to 48 hours the pomace was pressed again and the expressed juice 

 mixed with the juice of the tirst pressing and varying amounts of sugar, either 

 in the form of a sirup or added directly. 



The fermentation of the diluted juice proceeded normally but at a slightly 

 lower rate. Details are given of four mixed variety ciders, two single variety 

 ciders, and one perry prepared in this way. It is stated that although these 

 ciders and perry were not of as good quality as the average pure juice products, 

 most of them were quite palatable. 



Some experiments on ropiness in cider. — Eight pint bottles of cider were in- 

 oculated with two drops each of a pure culture of the bacillus previously found 

 to be the cause of ropiness in cider (E. S. R., 40, p. 414). The inoculated and 

 control samples were kept at 15* C. and examined at intervals for over a year. 

 No trace of ropiness in the inoculated samples was discovered for nearly a year, 

 when all but one developed the disorder, as did two of the controls. 



The relation between the rate of fermetitation and the content of nitrogenous 

 m<itter in apple juice. — To study the relation between the rate of fermentation 

 and the amount of nitrogen present in the juice, the juices from six varieties 

 of apples were placed in 125 gm. quantities in Erlenmeyer llasks which, after 

 sterilization, were provided with fermentation locks closed with sulphuric acid. 

 After inoculating the juice in each flask with a trace of pure yeast the flasks 



