14 EXPERIMENTS ON PROCESSING PERSIMMONS. 



STUDY OF METHODS OF APPLYING ALCOHOL. 



The next study was undertaken to determine experimentally if 

 the alcohol which it was supposed was necessary in causing the tannin 

 to become insoluble in advance of the softening of the fruit could not 

 be applied in such a way that the humidity would be greatly reduced. 

 By using glass or metal containers so arranged that they could be 

 closed air-tight, and thus avoiding the use of wooden vessels which 

 must be soaked to be made tight, by applying concentrated alcohol 

 in several successive small charges if found necessary, and by using an 

 absorbent for water vapor, it was hoped to be able to process the 

 fruit without the intense humidity incident to the Japanese method. 

 With these objects in view, the three following experiments were 

 made. The results were surprising. It was found that persimmons 

 readily become nonastringent while remaining firm when merely kept 

 in carbon dioxid without using alcohol. 



Experiment 5. — In tins case alcohol was applied in varying amounts 

 to persimmons kept in carbon dioxid. -Five 10-inch tubulated 

 desiccators were employed as containers. Each was fitted with 

 two-holed rubber stoppers carrying delivery tubes and was provided 

 with a strip of blotting paper 24 inches long by 5 inches wide, which 

 was so placed in the upper part of each desiccator as to nearly com- 

 pletely line the sides. Okame persimmons just received direct from 

 Florida by express were used. Seventy-one fruits were divided into 

 six lots, and each lot was weighed. One contained 1 1 fruits, the others 

 12 each. The selection was so made that as far as possible each lot 

 consisted of equal proportions of specimens of different degrees of 

 ripeness as judged by color. Five lots were placed in desiccators, 

 and the sixth lot was kept outside as check. In lot A no alcohol 

 was used. In lots B, C, D, and E the desiccators were charged with 

 5, 10, 15, and 25 cc of 95 per cent alcohol, respectively, by distributing 

 it on the strips of blotting paper. After filling each desiccator with 

 fruit and closing it, the air was displaced by carbon dioxid. In 

 displacing the air in the desiccators charged with alcohol, the carbon 

 dioxid was first saturated by running it through a Reiset absorption 

 tube * containing alcohol, an apparatus consisting of a wide glass 

 tube containing silver or platinum diaphragms for " scrubbing" 

 gases. 



The experiment was begun on October 17 and the fruits were 

 examined four days later. The results were as follows: In lot A, 

 where carbon dioxid only was used, all of the fruits were firm. The 

 most highly colored specimen was nonastringent, the next in point 

 of color was also nonastringent. A fruit showing a considerable 

 proportion of green in its epidermis contained traces of soluble tannin, 

 while still more tannin was found in a more immature specimen. 



* Hempel's Gas Analysis, p. 83. 



