FOODS HUMAN NUTRITION, 861 



digested in 3.19 hours fruui Ijleaehed rtoiir. iiud iu 2..'I1 hours from unbleached 

 Hour. The time of digestiou in pancreatic solutions of the l)alved gluten and 

 iif the bi'ead was iu favor of the unbleached product. The experiments made 

 with the keeping quality of bread made from bleached and unbleached tlour 

 demonstrated the antiseptic effect of the bleaching agent. 



" It has been demonstrated that when the diazo or like action took place, the 

 acid acted upon the gluten of the flour changing its comi)osition so that nitrogen 

 gas was given oft" when the flour was treated with an acid." 



Effect of bleached flour extracts on rabbits, E. F. Lado and II. L. White 

 (Nortli Dakota 8ta. Spec. Bui. !), iip. 15-26). — The authors have tested the 

 effects on rabbits of alcoholic and aqueous extracts of bleached and unbleached 

 tlour. 



Quotations from their conclusions follow : 



" There are produced in flour, as the results of artificial bleaching, toxic 

 bodies. . . . Alcoholic extracts prepared from unbleached flour a Ad fed to rabbits 

 did not affect them. Alcoholic extracts prepared in the same manner from 

 commercially bleached flour and fed to the rabbits in the same way caused 

 their death within a few hours. Alcoholic extracts i)repared from overbleached 

 dour in the same manner and fed in the same way to rabbits caused their im- 

 mediate collapse and death. 



"Aqueous extracts i)repared from overbleached flours when fed to rabbits 

 caused their immediate collapse and death. Alcohol and aqueous extracts from 

 overbleached flour, when neuti'alized with sodium bicarbonate, and fed to rab- 

 bits, caused the death of the rabbits in a short time, demonstrating that it was 

 not the acidity that produced the death of the rabbits. 



"In preparing aqueous extracts all nitrite reacting material disappeared; 

 hence, the death of the rabbits, in this case, must have been due to the presence 

 of other toxic material than that <tf nitrites." 



Experiments on the spoilage of tomato ketchup, A. W. Bitting ( U. aS*. Dept. 

 Agr., Bur. Chem. Bui. 119, pp. 31, pis. 2, figs. 5). — Experiments on the manufac- 

 ture of tomato ketchup without chemical preservatives under factory conditions 

 and- upon a commercial scale are reported. In addition, experiments with 

 sodium beuzoate and the household preservatives salt, sugar, spices, vinegar 

 and acetic acid, and oil were also made, as well as studies of Penicillium in 

 ketchuij. It is stated that the product obtained when ketchup was made with- 

 out preservatives was of excellent consistency, flavor, and color, and the results 

 in the author's opinion prove " that such a ketchup can be made and delivered 

 to the consumer in perfect condition ; the product in question having already 

 stood 10 mouths, unopened, without showing the slightest indications of 

 spoilage. . . . 



"The formula employed regularly in the factory where the exj)eriment was 

 conducted was used, but other recipes could be ada[)ted without changing the 

 character of special brands." The precautions observed in the manufacture of 

 such a product are given iu some detail. These were, in brief, the use of clean, 

 whole, rii)e fruit and high-grade salt, sugar, vinegar, and spices, thorough cook- 

 ing, use of sterilized bottles, and care and cleanliness at every step. 



While some of the condiments used had a limited antiseptic value, they are 

 only of incidental value for this purpose. 



"The spoilage of ketchuj) after opening depends more upon the temperature 

 of the jtlace in which it is keiit than on any variation in the manner of proces- 

 sing. Fresh ketchup held, after oiiening, at a temperature of !)r>° F. kept for 

 .'") days (jii an average without any trace of mold api»earing; at 72° it kept for 

 <> days; at 67° for 8 days; about 4(5° (refrigerator), 14 days; and at from 

 y()° to 60° for 27 days. These figures represent the time at which the first 



