Feb. 34, X919 



Apple-Scald 



203 



Apples stored in higher percentages of carbon dioxid than those given 

 in figure 11 soon developed a disagreeable alcoholic taste, but if they 

 were removed after a few days' exposure to the gas they were found to 

 have but little, if any, of this objectionable taste and to have developed 

 a decided resistance to scald. The results of two experiments of this 

 sort are given in Table IV. The apples were Grimes of the lot described 

 in the legend of figure 7. 



In the first experiment the taste of the apples was slightly affected 

 by the exposure to carbon dioxid, but in the second experiment the 

 apples exposed to carbon dioxid had as good a taste as those held 

 continuously in moist chambers. In both cases the treated apples 

 developed color in storage very much more slowly than the untreated. 

 It would seem from the 

 results that the carbon 

 dioxid had produced a 

 very decided inhibition 

 of the activities of the 

 apple, and thus led to 

 scald prevention. 



OXYGEN 



In the experiments 



r 



Fig. 6. — Graphs showing the eHect of temperature on appel-scald at the 

 end of s, 7, 9, II, 13, 16, and 19 weeks. The dotted graphs showthe 

 amount of scald that was evident after removal from storage at 

 the end of the given week and holding the apples at 20° C. for 3 days. 

 The apples were from heavily irrigated Grimes trees at Wenatchee, 

 Wash. They werepirkedonSeptcmbcr27, shipped to Washington, D. 

 C. , in iced pony refrigerators, and the experiment started on October 3 . 



with carbon dioxid re- 

 ported in figure ii the 

 oxygen of the air was 

 usually slightly below 

 normal, but with the ex- 

 ception of (c) and (d) 

 under B there was never 

 a deficiency of more than 

 I or 2 percent. With(c) 

 the average carbon di- 

 oxid content of the air 

 after the first two weeks 

 of the experiment was 6 per cent and the average oxygen content 8 per 

 cent, while with (d) the average carbon-dioxid content for the period v/as 

 14.5 per cent and the average oxygen content 6.9 per cent. In both cases 

 any pressure or suction was prevented by a small U -tube opening closed 

 with oil. The results given in figure 1 1 give no evidence that these 

 deficiencies in oxygen had any tendency either to increase or decrease 

 the amount of scald. The apples seemed normal at the end of the experi- 

 ment, with the exception of a very faint trace of an aromatic musty flavor. 

 In an earlier paper ' experiments were reported indicating that slight 

 increases (increasing the percentage from 21 to 24) in the oxygen content 



1 Brooks, Charles, and Coolev, J. S. effect op temperature, aeration, and humidity on jona- 

 THAN-spoT AND sc.\LD OF ^\PPLES IN STORAGE. In Jour. Agr. Research, v. ii, no. 7, p. 287-318, 23 fig., pi. 

 33-33. 1917. Literature cited, p. 316-317. 



98356°— 19 2 



