A CHEMICAL STUDY OF CRANBERRIES 93 



Samples were taken from the boxes at monthly intervals until there had 

 developed a proportion of rotten berries that rendered a variety useless for 

 further storage. Total acids were always determined in the fresh , sample, 

 but dried material was used for total sugar and dry matter. 



About three quarts Mere removed for each sample and sorted by hand. 

 The proportions of sound and unsound berries were recorded for comparison 

 of keeping quality of the varieties. Sorting by hand is more thorougii than 

 machine sorting as used for shipment. Berries just beginning to decay were 

 removed by hand but such fruit would as a rule go through the machine witli 

 the sound berries. 



The varieties differed considerably in their resistance to rot. To some 

 extent this may be a varietal quality but resistance may be overcome by the 

 presence of much disease on the bog from which the berries came. Stanley 

 was the least resistant and was two-thirds rotten by January 10, 1929. On 

 February 7 Holliston, McFarlin and Pride were more than half decayed. Cen- 

 tennial was about half spoiled, and Shaw's Success was 40 per cent bad. 13y 

 March 11 Bugle and Randall were more than 40 per cent decayed, while 

 Chipman was not over 2-5 per cent spoiled. 



The analytical data for both series of varieties are combined in Table 3. 



Centennial had distinctly the highest percentages of sugar and Center- 

 ville was next. The other eight varieties were much alike in composition. 



Changes in composition during storage were most noticeable in the per- 

 centages of sugar. Every variety showed a decrease in sugar in the second 

 sample. Centennial, Holliston and Pride continued to show a decrease until 

 they were no longer sampled. Stanley was sampled but twice. Bugle, Chip- 

 man and Randall had a final percentage of sugar nearly as high or higher 

 than the first percentage. This was probably due to the last samples having 

 been stored for a month in the electric refrigerator, which has a dry at- 

 mosphere and tends to dry any material stored within it. 



Centerville and Shaw's Success appeared to show selective decay of the 

 berries making up their respective lots. Both lots showed a wide range in 

 size of berries and to some extent variations in shape, as though the varieties 

 were not pure strains. As decay progressed the largest berries appeared the 

 least resistant. So it seems that there may have been a somewhat diff'erent 

 type of fruit at the last sampling. 



Holliston showed the most loss in sugar during storage, and this loss was 

 undoubtedly due to respiration. The variety also showed a noticeable peculi- 

 arity in its decay. A large proportion of its rejected berries while soft were 

 not rotten but had the character of smothered berries in unventilated pack- 

 ages. The HolJistons, however, were in a standard box with ventilated sides 

 like the other varieties. It appears that Holliston is a variety that perhaps 

 imdergoes respiration more actively than the other varieties. 



The losses of sugar are due to respiration within the berries, as shown by 

 this Experiment Station in some earlier work. The shrinkage in acids is also 

 due to the same cause. Furthermore, the fruit may lose water by drying if 

 stored where there is free movement of air about them. The actual rate of 

 shrinkage in lots of cranberries due to chemical change is difficult to measure 

 because any given quantity of the fruit will almost surely develoj) some decay 

 in a few days and render the losses of sound fruit uncertain. Losses in weight 

 for short periods are not large enough to overcome the errors which may oc- 

 cur in successive weighings. 



