16 BULLETIN 452, U. S. DEPARTMENT OF AGRICULTURE. 



compared with other districts. Such little-grown varieties as Clevener 

 and Diogenes give a juice of very deep color and are desired for 

 blending in making red wines. The grape-growing districts of New 

 Jersey need further attention before it will be possible to draw con- 

 clusions of value on the quality of the crop. 



SUMMARY OF DATA ON SUGAR AND ACID FOR FIVE YEARS. 



Table 3 brings together the results for sugar and acid determinations 

 of all the varieties, with a few exceptions, examined during the five 

 years' work, 1908, 1909, 1910, 1911, and 1913. The exceptions are 

 the muscadine varieties and a number of unnamed and undissemi- 

 nated seedlings. When more than one sample was analyzed the 

 average is given. The data from which this table is compiled are the 

 same as given in the tables of Bureau of Chemistry Bulletin 145, pages 

 20 to 35, and in Table 1 of this bulletin. So far as possible the results 

 are grouped by districts for those kinds of grapes of which a considerable 

 number of samples have been examined from several districts. The 

 following groups are used: "Northern Ohio" includes the vineyards 

 along the shore of Lake Erie and the islands off Sandusky; "New 

 York" includes the Geneva, Keuka, and Chautauqua districts; 

 other northern districts, from which samples did not distinctly 

 represent any one district, are given as "Other Northern," and if for 

 the reason that only a few widely-scattered samples of a variety were 

 collected no division is made into districts the samples are given as 

 from "All Northern." Southern samples were taken from restricted 

 areas and are so grouped. 



The summary presented in Table 3 covering the five-year period 

 shows some interesting comparisons on samples which were taken 

 with care and in sufficient number to warrant the belief that 

 they represent the facts.' For instance, Catawba for northern Ohio, 

 one of the rather strongly-acid fruits, shows a very narrow range of 

 average sugar for the several years, from 18.05 grams to 20.78 grams 

 in 100 cc of juice during four years, but with a variation of acid from 

 0.709 gram to 1.155 grams in 100 cc or in acid-sugar ratios a varia- 

 tion from 1 to 15.6 to 1 to 28.6. 



Take also the example of Concord, one of tne varieties of medium 

 content of sugar and moderately low in acid. Here again the range 

 in sugar content is slight, being from 15.74 grams to 18.51 grams in 

 100 cc with an acid range from 0.466 gram to 0.757 gram in 100 cc. 

 This gives acid-sugar ratios running from 1 to 22.4 to 1 to 37.3. 



Delaware shows the most phenomenal acid-sugar ratio of any 

 variety examined. Comparing only the northern Ohio samples for 

 1909, 1910, and 1911, because these are the more representative, the 

 ratios extend from 1 to 26.0 to 1 to 43. S. Certainly the latter ratio 

 is entirely too wide for a properly balanced grape juice or for a dry 

 wine. Such low acidity endangers the keeping quality of the products* 



