MISCELLANEOUS 



407 



removal to air the sprouts return to the original pH, but there is no increase 

 in the ascorbic acid content. The CO 2 has a similar effect at all tempera- 

 tures from 2° to 27° C (36° to 81° F) and the fall is greater m the buds than 

 in the sprouts. Since, as shonii by the curve, even low concentrations of 

 CO2 cause a marked destruction of ascorbic acid, no doubt the accumulation 

 of CO 2 due to respiration in the packages during shipping and marketing 

 leads to a great loss in the vitamin C content of the sprouts by the time 



10 



I4. 

 O 



o 

 c 



UJ 

 Q. 



z 



UJ 



o 



>- 



X 



o 



a 



o 



< 



m 

 a 

 o 

 o 



10 



< 



ii. 



o 



eb 



2 



PERCEJMTAGE OF CARBON DIOXIDE 



Figure 162. The effect of CO2 on the ascorbic acid content, rate of respiration, and 

 pH of asparagus tissue during storage of 24 hours at 22° C (72° F). The oxygen uptake 

 is mg of O2 per 100 g of tissue. 



they are sold. This curve shows that the oxygen absorption rate (mg of 

 O2 per 100 g of tissue) of asparagus sprouts is reduced by CO 2, a fact 

 mentioned above. 



Carbon dioxide ^" causes marked reduction in the ascorbic acid content of 

 green bananas with four days' storage at 19° C (66° F); 60 per cent CO2 

 gives 66 to 85 per cent reduction, even 16, 24, and 40 per cent give great 

 reductions and concentrations of 3 to 5 per cent cause 10 to 20 per cent 

 reduction. Carbon dioxide has little effect on the ascorbic acid content 

 of fruit in the yellow ripe stage. At any stage of ripening where CO2 

 causes a reduction, the ascorbic acid rises back to normal some time after 

 the fruit is removed from the CO2; also fruit kept in CO2 from the green 

 stage to complete ripening ended up with about the same ascorbic acid 

 content as fruit brought to the same stage of maturity in air bearing no CO2. 

 Carbon dioxide caused the juice of bananas to become more alkaline by 0.2 



