1 88 Journal of Agricultural Research voi. m. no. 3 



with which ripening occurs in different bunches of bananas and of the 

 rate of starch hydrolysis during ripening in relation to changes in the 

 rate of respiration. The first and second experiments were made in 

 cooperation with Messrs. C. F. Langworthy and R. D. Milner, Nutrition 

 Investigations, Office of Experiment Stations, who measured the weight 

 changes on ripening, the carbon dioxid, the water and the heat evolved, 

 and the oxygen absorbed. The composition was determined before and 

 after ripening. Green bananas selected from commercial shipments just 

 received from the West Indies were used in all cases. 



FIRST EXPERIMENT 



Six bunches of green bananas were used. They were evenly matured, 

 so far as could be judged from the comparative intensity of the green 

 color. The top and the bottom of the stem of each bunch were trimmed 

 smoothly, and all injured fruits whose pulp might have been infected as 

 a result of mechanical injury were removed. 



For analysis, six fruits were cut from each of five bunches and eight 

 fruits taken from the sixth bunch, which was larger than the others. 

 The samples were taken from the inner and the outer portions of the 

 "hands" at the top, the middle, and the bottom of each bunch, cutting 

 them off where the short stem by which the bananas are attached to 

 the stalks was most constricted. After ripening, samples were removed 

 from the same "hands" from which samples had been previously taken, 

 but they were cut from places removed from where the preceding samples 

 had been attached, in order to avoid possible effects of local stimulus 

 to adjacent fruits due to cutting. No indication of such effect, how- 

 ever, was noticeable. 



The samples of green or ripe bananas were first weighed and then 

 separated into peel and pulp. The peels of green bananas adhere closely 

 to the pulp, and appreciable losses from evaporation are unavoidable. 

 .\fter separation, the peel and the pulp were weighed, to determine their 

 respective proportions and the losses from evaporation. To express the 

 analyses in terms of the original bananas, it was necessary to correct 

 for this evaporation. To this end the loss in weight on peeling was 

 arbitrarily divided equally between the respective weights of peel and 

 pulp, and the percentages of peel and pulp were then calculated. The 

 samples of peel and pulp were ground by passing them through a food 

 chopper. 



The methods of analysis used in this and succeeding studies were as 

 follows : 



Solids were determined by evaporation in vacuo at 70° C. 



Ash and soluble alkalinity of ash were determined by the official 

 methods. • 



' Wiley, H. W., et al. OflBdal and provisional methods of analysis. Association of OSScial Agricultural 

 Chemists. U. .S. Dept. Agr., Bur. Chera. Bui. 107 (rev.), p. j8, 102. 190S. 



