JELLY MAKING WITH HAWAIIAN FRUITS. 
obtained from different localities. These differences have been 
attributed to variations in the composition of the guava juices, which 
variations in turn were thought to be due to the widely differing locali- 
ties and seasons, as well as to varietal differences, individual varia- 
tions in the same variety, and varying stages of maturity of the fruit 
when it was used. 
Variations due to widely differing localities and seasons. — To deter- 
mine the effect of localities and seasons upon the jelly-making qualities 
of the juices, three guava-producing areas, representing widely 
differing conditions of climate, altitude, and season, were selected 
for study. Guavas from each of the areas were obtained from time 
to time and their juices were partially analyzed. 
A uniform procedure was maintained throughout the experiment. 
In each test 5 pounds of medium ripe guavas were cooked with 2.5 
pounds of water in an uncovered 2-gallon granite-ware container. 
After the mass had been constantly stirred to prevent it from sticking 
to the container and gently boiled for an hour to effect complete 
dissolution of the partly ripe fruit, it was allowed to drain overnight 
in a double cheesecloth ba°:. Only the juice which drained through 
without pressure was used in the experiment. 
The moisture content of the fruit was determined by drying a 
pulped sample to constant weight at 100° C. Only the Brix corrected 
figures, pectin number, and acidity of the juices were determined, 
since the pectin and acid content are the only essential constituents 
for jelly making. The variations in the sugar content of the juice 
of a fruit are generally too slight to be of importance in this connection. 
Table 3 gives the effect of localities and seasons on the composition 
of guava juices. 
Table 3. — Variations in the composition of guava juices due to location and season. 
Location. 
Oct. 
Windward Oahu: 1 
Kailua 
Do 
Do 
Leeward Oahu: 3 
Manoa : Sept. 
Do ! Sept. 
Do j Sept. 22', 1921 
Do Nov. 8,1921 
Pa'olo I Sept. 8,1921 
Manoa : Feb. 2,1922 
Mountain slopes: * 
Tantalus Sept. 
Aug. 22,1921 
Sept. 19, 1921 
4, 1921 
8, 1921 
16. 1921 
Do. 
Do. 
Do. 
Jan. 
Jan. 
Feb. 
12. 1921 
11. 1922 
27,1922 
3,1922 
Moisture 
in 
guava. 
Per cent. 
81.8 
85.3 
82.6 
86. 5 
83.3 
82.3 
83.6 
87.8 
87.0 
87.5 
Juice. 
Drained 
juice. 
Brix 
reading. 
Pectin 
No. 
Aciditv 
(asHtSOO 
Cubic 
centimeters. 
1,110 
1,180 | 
1,100 ! 
1,130 I 
1,180 j 
1,185 
1,200 
1,490 
1,205 
1,150 
1,415 
1,200 
1,210 
Degrees. 
8,7 
8,0 
9.4 
8.1 
8,3 
8,1 
8.7 
6.9 
7.0 
9.2 
8.4 
7.7 
7.4 
8! 
H 
'I 
Per cent. 
0.99 
1.10 
.82 
1.50 
1.58 
1.66 
1.32 
1.39 
1.61 
1.24 
1.09 
1.16 
1.46 
1 The guavas from Kailua, Manoa, and Palolo were composite samples that were taken from ton lots of 
the fruit. Those from Tantalus were picked from only a few trees each time. 
* Elevation 100 feet, 
s Elevation 300 feet. 
« Elevation 1,500 feet. 
Table 3 shows that location has a very marked effect on the acidity 
of the juices of the guava. The proportion of acidity in the juices of 
guavas from the windward side of Oahu was less than 1 per cent, 
while in fruits from the leeward side it averaged nearly 1.5 per cent. 
The pectin content was highest in fruit from the windward side and 
lowest in that from the mountain slopes, but it was sufficiently 
