RECENT WORK IN AGRICULTURAL SCIENCE 



AGRICULTUEAL CHEMISTRY— AGROTECHNY. 



Eiochemical changes in cotton seed in storage, J. B. Rather (Arkansas 

 Sta. Bui. 125 (1916), pp. 3-18). — Studies are reported of the changes in stored 

 cotton seed with reference to the loss of vitality and the availability from the 

 standpoint of the cotton-seed-oil mill and the live-stock feeder. 



The fat in ground cotton-seed was found to hydrolyze rapidly into fatty acids. 

 This hydrolysis may amount to 85 per cent of the fat in three weeks. 



In cotton-seed from seed cotton gathered dry and stored for three weeks in 

 a common farm cotton house and in a cotton-oil mill seed house in lots of 4,500 

 and 7,500 lbs., respectively, no appreciable changes except a reduction in the 

 moisture content occurred. Dry cotton seed stored in a common farmhouse in a 

 3,000-lb. lot in a pile 12 by 12 by 4 ft. did not deteriorate during the period of 

 oil-mill operation. A slight loss of moisture in the samples caused correspond- 

 ingly small increases in the percentage of protein and fat. The free fatty acids 

 in the fat and the total acidity of this seed did not increase to any significant 

 extent. Cotton seed stored in an oil-mill seed house in a 5,000-lb. lot in a 

 pile 12 by 12 by 6 ft., dried out in storage and then heated. During heating 

 the free fatty acids in the fat increased from 2.26 to 11.89 per cent, and the 

 total acidity from 28 cc. of normal alkali per kilogram of seed to 91 cc. A slight 

 protein hydrolysis was observed. 



The free fatty acids in the fat of samples of fresh cotton seed at the time of 

 picking was less than 2 per cent of the fat, and the total acidity of the seed was 

 about 26 cc. of normal alkali per kilogram of seed. It is deemed probable 

 that the increase in the free fatty acids and in acidity is due to heating and 

 not to aging of the seed. Cotton seed stored in lots of 1,000 lbs. did not de- 

 teriorate in storage. 



It is indicated that in extreme cases of heating the carbohydrates, fats, and 

 proteins of the stored seed are attacked, and analytical data submitted show 

 that the hydrolysis of the fat may reach 70 per cent and that of the protein 35 

 per cent. When cotton seed heats the fats decompose the most readily, and it 

 was observed that this msiy take place to a considerable extent before the otlier 

 constituents begin to undergo change. The acidity of fresh cotton seed is re- 

 garded as due only partially to fatty acids from the fat, but it is pointed out 

 that in heated seed the content of free fatty acids is as great as, or greater 

 than, is necessary to account for the total acidity. It is concluded that unless 

 cotton seed heats badly the meal made from it will be as valuable for feeding 

 as meal made from unheated seed, but that the oil from even slightly heated 

 cotton seed is worth considerably less than oil from fresh seed. 



Note on American charlock oil, H. S. Bailey and L. B. Burnett (Jour. 

 Indus, and Engin. C'hem., 8 (1916), No. 5, p. Jf29). — The authors report the 

 physical and chemical constants of the expressed oil, the ether extract, and the 

 petroleum ether extract obtained from pure charlock (Brassica arvensis) seed. 

 It is indicated that the oil can be used in soap making and possibly in cheap 

 paints. Its value for food purposes has not been investigated. 

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