[macfarlanœ] on THE ANALYSIS OF WHEATEN FLOUR 63 



The wheat crop of 1903 in the North-west was recognised as a 

 reniai-kahly good one, and as capable of being taken as a standard by 

 wliich to judge the products of subsequent seasons. The flours from 

 that crop which are described in this paper as belonging to the season 

 1903-i, gave great satisfaction to the bakers, who were able to produce 

 from them breads of excellent quality with the greatest ease. When the 

 Hours of the next crop came on the market (1904-5) they were found 

 to be troublesome to work, and to require delicate handling in order 

 to the production of good bread. During doughmaking and fermenta- 

 tion they behaved well, the sponge being light and rising readily. But 

 this favorable shewing did not continue when the loaves were introduced 

 into the oven. The expansion ceased and it even seemed as if a col- 

 lapse and a lessening of the porosity took place. With regard to the 

 flours from the crop of 1905, the disadvantages of the previous seasons 

 flours were(,not observed to anything like the same extent and they earned 

 the character of being much better, and of resembling to a greater 

 extent the flours of 1903-4, although they did not come up to the latter 

 in excellence. 



Now, if we examine the lines of figures in Table II, we find that the 

 one which most closely corresponds to the variations in the crop char- 

 acters Just mentioned, is that which gives the percentage of pure gliadin 

 from the total proteids of the flour. It will be observed that, in the 

 case of every one of the different brands, that percentage is highest in 

 the flours from the crop of 1904, the year in which they shewed the 

 greatest defects for baking purposes, and also that the same percentage 

 is lowest for the products of the pattern year of 1903. With regard to 

 the flours of last year they generally occupy an intermediate position 

 betwixt those of the two other seasons, although some of them shew th(3 

 same proportion of the gliadin to other proteids as the flours of 1903. 

 It ds ordinarily accepted that gliadin or the alcohol soluble proteids of 

 gluten are those to which its elasticity or adhesiveness are due, and a 

 high percentage of these is usually supposed to indicate a flour of 

 superior quality. According to the figures recorded in Table II, it 

 appears, however, that the higher percentage of gliadin in the flours of 

 1904 was one of the causes of their defective character. 



The average percentage of gliadin in the fluor proteids of 1903 

 according to the above determinations is 36-45. If all the other pro- 

 teids in the flour are regarded as glutenin then the proportion of gliadin 

 to glutenin is as 36-45 to 63-55. But this assumption cannot be correct 

 seeing that the water soluble proteids have not the properties of glutenin. 

 If the water soluble proteids are deducted from the total proteids, and 

 the proportion is calculated in the remainder of gliadin to glutenin, the 



