1 94 ANNUAL REPORTS OF DEPARTMENT OP AGRICULTURE. 



A general comparative study of the mold flora of the foodstuffs 

 subjected to inspection has been begun, carefully distinguishing acci- 

 dental organisms present as resting spores and those active in pro- 

 ducing changes in the substrata. 



The study of the effect of storage on bottled waters has shown that 

 B. coli, B. typhosus, and B. dysenteriae inoculated into bottled 

 mineral waters do not multiply, except the first two, which, in some 

 instances, increased slightly during the first two days of storage. 

 This was followed by a decrease in numbers. In a water practically 

 free from dissolved solids, B. coli persisted in greatly reduced num- 

 bers for more than six months. A yellow micrococcus, multiplying 

 rapidly, was found to be due to air contamination. The manner in 

 which commercially bottled water changes its flora in one to six 

 months was studied in considerable detail. Bulletin No. 369, " Bac- 

 teria in Commercial Bottled Waters," was issued. The results of a 

 comparison of bile with lactose buillon for determining the presence 

 of B. coli in water were also published. 



The United States Public Health Service has been assisted by the 

 Bureau of Chemistry in making sanitary surveys of oyster beds. 

 The results of a study of the preparation for and the transportation 

 to the market of oysters, of a comparative study of bacteriological 

 methods for the examination of oysters, and of a comparative bac- 

 teriological examination of oyster-shell liquor and oyster meats have 

 been prepared for publication. 



In cooperation with the Bureau of Animal Industry a manuscript 

 has been prepared showing that one member of the group of molds 

 known as Aspergillus niger produces 10 times as much oxalic acid 

 as others, without accompanying differences in structure. 



It has been found that the common molds Penicillium camemberti 

 and Aspergillus niger produce substances reacting with ferric chlo- 

 rid like phenols, a matter of significance in detecting moldiness in 

 foods. It has also been found that the so-called salicylic acid re- 

 action of the Japanese distilled liquor, sake, is in reality due to 

 an acid formed by the mold used to ferment the rice from which 

 sake is distilled. Mold products of this type may be mistaken for 

 preservatives such as salicylic acid. 



An as yet undetermined species of ergot was discovered in cara- 

 way seed. 



Anti-neuritic substances. — A variety of synthetic compounds 

 have been made and tested physiologically. Several have been found 

 to possess anti-neuritic properties similar to natural " vitamines." In 

 collaboration with the United States Public Health Service a crys- 

 talline anti-neuritic product was isolated from yeast and some evi- 

 dence obtained regarding its identity. A study of the nutritive and 

 medicinal value of cod liver oil and extracts thereof was begun. One 

 paper has been published and three nearly completed. 



Cereals — Flour. — Studies have been made upon the grading of 

 flour and upon the determination of grades of flour with especialref- 

 erence to the bleaching of flour. It has been found that the particles 

 of various sizes in flour differ in chemical composition and in baking- 

 qualities. The work on flour substitutes has been continued, and a 

 report on the determination of moisture in bread has been made. 

 Chemical studies have been made upon the changes that take place in 

 the deterioration of oats and in the bleaching of inferior oats. 



