34 Journal of Agricultural Research Voi. xviii, No. i 



solubility of those acid phosphates is declared to be greatly diminished 

 in the presence of alcohol, a fact which had previously been recognized 

 by Weiss (//) and by Swanson {14, 15). Weiss found that if ground 

 barley is first extracted with 96 per cent alcohol a subsequent extraction 

 with water yields a far smaller quantity of soluble phosphorus compounds 

 than a direct water extraction. Of the total phosphoric acid in 100 gm. 

 of barley, 79 per cent was found to be normally soluble in water by 18 

 hours' extraction at room temperature with addition of toluol. If the 

 same material was first treated with 96 per cent alcohol in a Soxhlet 

 extractor for 20 hours, a subsequent extraction with water yielded only 

 45 per cent of the total phosphoric acid contained in the meal, while not 

 more than 3.66 per cent had been removed by the alcohol. Weiss seeks 

 to explain this difference by assuming that the high phosphorus content 

 of the water extract is due to the action of enzyms, which he thinks are 

 destroyed by the alcohol treatment. This explanation, however, is not 

 in harmony with the more recent findings of Adler (i, 2, j). This inves- 

 tigator has made extensive studies of the various groups of acid-producing 

 ferments which come into play when ground barley or malt is extracted 

 with water. He found that these ferments, and particularly the phos- 

 phatases, are very resistant not only to the action of the common disin- 

 fectants such as chloroform, toluol, hydrogen peroxid, etc., but also 

 to dry heat, and that their activity is not impeded by cold alcohol, even 

 if present in high concentrations. 



It does, of course, not necessarily follow that the results obtained with 

 barley by these investigators will apply, without qualification, to corn, 

 oats, or rye. However, there is a strong probability that similar con- 

 ditions will prevail in all gramineous seeds; at any rate, the results 

 obtained with barley in Germany deserve the full attention of everyone 

 who is working along similar lines with other cereals. Schindler, for 

 example, would probably have hesitated in devising his above-mentioned 

 alcohol extraction method for determining corn acidity had he read the 

 paper of Weiss {ij) which was published two years previously. 



While recognizing the impossibility of suppressing acid-producing 

 ferments by means of cold alcohol, Iviiers and Adler {11) found that a 

 brief boiling with 96 per cent alcohol completely destroys these ferments. 

 They therefore make this boiling with neutral 96 per cent alcohol part of 

 their method for measuring the original acidity of ground barley and 

 malt. During the boiling, which is done in open beakers with occasional 

 stirring, most of the alcohol is driven off, and when the material has 

 reached a doughy consistency it is allowed to cool. Distilled water is 

 then added and the mixture permitted to stand for several hours with 

 occasional stirrings and the addition of toluol. The weight of the total 

 amount of liquid is then determined, and after the liquid is filtered a suita- 

 ble aliquot is titrated with Njio alkali. Liiers and Adler are well aware of 



