390 FIELD AND GARDEN PRODUCTS 



In this connection it must be borne in mind that within certain 

 limits an increase in moisture content results in a decrease of the 

 weight per measured bushel. In the samples used in these investiga- 

 tions the average decrease in weight per bushel was 1.34 pounds 

 as compared with an average increase in moisture content of 1.79 

 per cent. 



The average decrease in the weight per bushel due to the addi- 

 tion of moisture during the process of bleaching was 1.34 pounds; 

 however, this decrease in weight per bushel was not sufficient to 

 prevent the oats from being given a higher grade on account of the 

 improvement in appearance after bleaching. 



Odor Before and After Bleaching. Commercial oats, as they 

 reach the grain markets, vary greatly in quality, condition, and 

 color. The odors range from a natural odor common to oats when 

 harvested under favorable conditions down through a series of odors 

 acquired from various weeds, the most common of which is the rag- 

 weed, and from different kinds of damage, such as "ground dam- 

 age," mold, heat damage, etc. 



The sulphur bleaching of oats changes these odors and gener- 

 ally removes or overcomes them entirely, leaving a strong sulphur- 

 ous-acid odor when the oats are freshly bleached. The odor of sul- 

 phurous acid has a tendency to disappear, especially as the oats be- 

 come drier. The absence of the odors commonly found in natural 

 oats usually arouses suspicion that they have been bleached ; there- 

 fore, in order to supply the desired 1 odor and to make the detection 

 of sulphur-bleached oats difficult or impossible by physical examina- 

 tion, it is a common practice to mix unbleached oats with bleached 

 oats. The mixed grain is seldom questioned as having been 

 bleached ; nevertheless, a trace of sulphurous acid remains and may 

 be detected by subjecting the grain to a simple, qualitative, chem- 

 ical test. 



Germination Reduced by Bleaching. As bleached oats and 

 barley are frequently selected for seeding purposes because of their 

 exceptionally bright appearance, germination tests were made of 

 both grains before and after bleaching in order to ascertain whether 

 or not the vitality is affected by the bleaching process. The results 

 of these tests are given in the following table; 



