CITKUS PECTIN 9 
Table 11. — Composition of pectin solution and powder made in the laboratory 
Composition 
Product 
Total 
solids 
Ash 
Acid as 
citric 
Total 
sugar as 
invert 
Pectin 
Pectin solution: 
Original 1 
Per cent 
3.31 
2.24 
12.49 
94.95 
89.10 
Per cent 
Per cent 
0.38 
.35 
L80 
14.40 
6.90 
Per cent 
0.80 
.13 
Per cent 
0.82 
After fermentation 
.80 
After concentration 
0.88 
7.12 
9.81 
4.20 
Pectin powder: 
Original. . 
31.00 
After alcohol extraction 
44.70 
From another lot of lemon residue, 38 kilograms of concentrated 
extract was made by freezing. This was shipped to a powdered- 
milk company, which returned about 1,300 grams of very bitter 
powder, stating that the material could be dried satisfactorily by 
their process, but that much had been lost in their apparatus. An 
analysis of this powder showed the following results: 
Moisture (per cent) 3. 62 
Acid as citric (per cent) 6. 75 
Pectin (per cent) 43. 7 
Alcohol precipitate (per cent) 52. 9 
Protein (per cent) 5. 28 
Ash (per cent) 9. 14 
Water-soluble ash (per cent) 4. 19 
Alkalinity of water-soluble ash (cc. 0.1 iV hydrochloric acid per gram) 4. 5 
Alkalinity of water-insoluble ash (cc. 0.1 N hydrochloric acid per gram)__ 6. 3 
Reducing sugars (per cent) Trace. 
Soluble P 2 5 (per cent) None. 
Insoluble P 2 5 (per cent) 0. 40 
P 2 5 in ash (per cent) 4. 3 
Apparently concentrated pectin solutions can be powdered and 
then extracted with a suitable solvent to yield a satisfactory product. 
A 60 per cent alcohol, denatured with benzol, methyl alcohol, or 
ethyl acetate, can^be employed, if care is taken to thoroughly remove 
the denaturant when drying. 
As the spraying process is expensive and as the work previously 
conducted indicated that alcohol was the most suitable substance 
for the precipitant and the washing material, an effort was made 
to devise a process employing as little of the reagent as possible. 
Upon adding a viscous sirup of pectin to 13^ volumes of 95 per cent 
alcohol, a heavy gelatinous mass was thrown down. This mass 
could be freed from the solution by pressing or centrifuging, but it 
could be washed only with difficulty. Upon dissolving the unwashed 
pectin in water and distilling oft the alcohol, however, a pectin 
concentrate having only a slightly bitter taste can be produced. 
If the pectin extract is evaporated to dryness, it becomes tough 
and brittle and sticks to the container. After reduction to a fine 
powder, great difficulty was experienced in removing the bitter 
taste with hot 60 per cent alcohol. 
It finally became evident that if the pectin solution was concen- 
trated to a thick paste, containing from 25 to 50 per cent of solids, 
a minimum quantity of alcohol would remove the bitter substance 
22805°— 25f 2 
