16 
BULLETIN 47, HAWAII EXPERIMENT STATION 
Sugar ratio for grape jelly. — Table 20 shows the results of running 
a jelly series on each of the juices given in Table 19. 
Table 20. — Results of varying proportions of sugar, pectin, awl acid in grape jelly. 1 
JUICE A. 
Sugar 
ratio 
Length 
of 
time 
re- 
quired 
for 
Weight 
of 
jelly. 
cook- 
ing. 
Mia. 
Gms. 
3 
342 
2* 
378 
H 
432 
5 
481 
6 
536 
7 
608 
Pro- 
por- Total 
tion sugar 
of in 
sugar jelly, 
added. 
Spe- Boil- 
cific ing 
grav- tem- 
ity pera- 
"°C. tures. 
Pec- 
tin 
in 
jelly.* 
Acid 
in 
jelly. s 
Consistency. 
Taste. 
P.ct. 
43.8 
52.9 
57 
62.4 
65.3 
65. S 
7.9 
P.ct. 
52.4 
60.6 
64.6 
68.4 
70.7 
70.6 
1.21 
1.25 
1.27 
1.27 
1.29 
1.28 
°C. 
102.0 
103.0 
103.5 
104.0 
105.5 
105.5 
P.ct. 
0.83 
.76 
.66 
.60 
.53 
P. ct. 
0.98 
.89 
.78 
.70 
.63 
.55 
Finn; tender Too tart. 
do , Tart. 
do Excellent. 
do Do. 
Mellow; lacks body 
do 
Rather sweet. 
Sweet. 
.TCTCE B. 
3 
l 4 
n 
5 
4 
4 
5 
366 
421 
445 
52.7 
54.6 
59.4 
07.4 
61.4 1 
61.5 1 
65.3 ] 
73.0 
1.25 
1.25 
1.27 
1.29 
103. 
103. 5 
104.0 
105.0 
0.82 
.63 
.55 
.52 
1.04 
.81 
.70 
.67 
Firm; tender 
do 
do 
Mellow; lacks body. 
Tart. 
Excellent. 
Do. 
Rather sweet. 
JUICE C. 
4 
3 
222 
45.0 
53.9 
1.22 
103. 5 
O.SO 
1.05 
i 
6i 
266 
58.4 
63.8 
1.26 
104.5 
.66 
.88 
1 
5* 
327 
61.2 
67.2 
1.27 
104.5 
.54 
.71 
li 
6 
375 
66.7 
71.9 
1.29 
105. 
.47 
.62 
Firm: tender. 
....do 
....do 
. 62 Mellow: lacks body . 
Too tart. 
Excellent. 
Do. 
Rather sweet. 
1 These jellies were left exposed to the air. All jellies having a sugar ratio of less than 1 developed mold. 
Those having a sugar ratio of 1 or more did not develop mold in 3 weeks' standing. No crystallization 
occurred in anv of the lots. 
8 (Pectin number of juice X0.222X245) divided by (weight of jellyxlOO). 
3 (Per cent acid in juice X245) divided by weight of jelly. 
From Table 20 it is evident that (1) the maximum sugar ratios of 
juices A, B, and C are 1£, li, and 1, respectively: (2) the minimum 
proportion of pectin necessary to produce a jelly with sufficient body 
is about 0.56 per cent of the jelly; (3) the acidity of grape juice is 
probably never the limiting factor in jelly making, since the best 
flavors were produced with acidities of from 0.7 to 0.85 per cent of 
the jelly; (4) the jelly either lacks body or is of a mealy, granular 
texture whenever the total sugar in grape juice is about 67.0 per cent 
or over, and mold is likely to develop when the total sugar is less 
than about 60 per cent; and (5) the maximum sugar ratios of the 
grape juices, as determined by the above table, are about one-fourth 
lower than is given in the guava pectin table for the same pectin 
numbers. 
NOTES ON JELLY MAKING FROM THE ISABELLA GRAPE. 
Grape jelly is characterized by its very tender texture. Over- 
cooking guava jelly results in a tough, hard consistency, but over- 
cooking grape jelly causes an apparent breaking down of the pectin, 
which becomes a soft, granular mass. Grape jelly should not, there- 
fore, be overcooked. 
