54 STUDIES OF AMERICAN BARLEYS AND MALTS. 



But it is not always enough to know the weight per bushel and the 

 weight per 1,000 grains in order to properly select malt. One should 

 also determine other factors, such as mellowness, percentage of ger- 

 mination, water, protein, and extract, the color, odor, impurity, and 

 the diastatic power, etc., basing the decision on all of these results. 



From the entire study it is very evident that the variation in cli- 

 matic conditions throughout the country, the difference in soil, the 

 different methods of cultivation and rotation practiced all have 

 their bearing on the characteristics of barley, and from the great 

 variation in composition it is safe to assume that the United States 

 can produce barley of the first rank, whether 6-row T or 2-row varieties 

 be grown. As the climate varies greatly from one locality to another, 

 and such conditions exert the greatest influence on the quality of the 

 crop, care should be taken to select the seed and locality according to 

 the type of barley desired. For example, moist climates and localities 

 where plants have long periods of growth, especially between the 

 stage of flowering and maturity, generally produce a low-protein 

 barley. In such localities it would generally be impossible to grow 

 barleys rich in protein. 



CHANGES IN COMPOSITION DIKING MALTING. 



One of the most interesting and instructive series of results ob- 

 tained in this work relates to the changes which each constituent of 

 the barleys underwent during malting. This is shown in Table IV. 

 These figures were obtained by analyzing the malts, and then calcu- 

 lating the malt analyses to the basis of the corresponding barleys by 

 multiplying the results of the malt analyses by the factor obtained 

 by dividing the weight of 1,000 grains of malt by that of 1,000 grains 

 of barley. This factor averages about 89, but as a rule the fac- 

 tor found by actually weighing the barley and the amount of malt 

 obtained therefrom on a laboratory scale was used. In several cases. 

 however, the factor 89 was used in the conversion of the malt figures 

 to the basis of the barley. This was the case wherever the results 

 showed that an apparent error had been made, or where a sample 

 of either the malt or barley had been lost before the weight per 1,000 

 grains was obtained. The loss in malting a barley is due to the loss 

 of soluble constituents and respiration of carbonic acid and to the 

 formation of the radicles. On the other hand, there is a slight gain 

 in weight due to the fixation of water during the conversion of starch 

 to sugar, and possibly also to the hydrolysis of the proteins/' The 

 losses on malting were then calculated by dividing the difference be- 

 tween the percentage of each constituent in the barley and in the 

 malt (calculated to the barley basis) by the percentage of that con- 

 stituent in the barlev itself. 



" Lonir. .1. Amer. Them. Soc.. 1907. '2U: I".*:,. 



