COMMERCIAL CANNING OF FOODS. 49 
{nd overheated fruit is easily determined under the microscope. In the former case 
ftis rare to have more than one or two pieces in a can, and then only in occasional 
fans. When due to prolonged heating, more pieces and cans show this defect in 
pearance. 
Piums (PRUNUS DOMESTICA). 
Several varieties of plums are used in canning, the popular ones being the green 
hage, the yellow egg, and the Lombard. The Sues is gathered just as it is beginning 
turn soft, and the preliminary treatment is the same as for apricots. The California 
olums are graded for size, being run over screens having openings 32, 40, 48, and 56 
irty-seconds of an inch in diameter. They are washed, and the imperfect or spotted 
it picked out; ordinarily the plum is not peeled. The cans are then filled, some 
are being necessary in placing the plums so that the fill will be uniform. Hot sirup 
added, and the cans processed at 212° F. for from 8 to 14 minutes. 
Eifect of varying degrees of sirup on green gage and yellow egg plums. 
| Density of sirup Gross 
| 
Weight of)Weight of, Weight of} Brix Reduc- 
Sucrose. | Acidity. 
| 
(degrees). weight. po contents. | fruit. sirup. | reading. pne sugar. 
Green gage plums; 
weight of fruit, 350 
grams, No. 2 can; 
examined Oct. 23, 
1912, Apr. 11, 1913, Grams Grams Grams 
Mar. 26, 1914: Grams. | Grams. | Grams. | Grams. «| Degrees. \per 108 ce.|per 100 cc.\per 100 cc. 
695 595 328 267 8.9 4.00 1.54 0. 90 
WWEOD ss. Sicteisine 685 585 305 280 8.9 4.87 13 93 
690 590 390 200 9.3 5. 48 OL 91 
700 600 335 265 13.4 ego 1,43 94 
0) Se Se ese 700 600 330 270 1357, 7. 87 1.54 88 
700 600 340 260 13.3 9. 20 .14 92 
705 605 330 275 16.8 8. 37 4, 63 .92 
i lo eee 707 607 335 272 16.5 10. 75 1a9 91 
690 590 340 250 1657 12. 23 29 . 92 
{ 712 612 327 285 ile? 10. 75 7.50 . 93 
) 3) ase tae ea era 715 615 330 285 22.4 13. 00 4, 63 . 85 
| | 725 625 335 290 2251 17, 38 19 . 82 
735 635 320 315 26.9 11. 87 10. 80 91 
i, AUS See Ss eS 730 630 320 310 27.0 17. 00 5. 70 . 86 
730 630 350 280 26.5 22. 76 . 20 91 
742 642 305 337 32. 4 16. 75 13. 06 . 83 
Se ee oS a 737 637 305 382 32.8 23. 75 2.14 392 
755 655 360 290 31.8 26. 25 1.13 . 88 
759 655 307 348 36. 6 16. 51 16. 51 . 85 
Ot oS: 755 655 310 345 37.6 22.00 10. 93 . 78 
760 660 345 315 36. 4 30. 90 2. 02 . 92 
Yellow egg plums; 
weight of fruit, 560 
grams, No. 24 can: 
Water { 1,010 870 540 330 10.6 5. 25 . 00 1.24 
1 RRS arrears 1,002 862 525 337 10.3 5. 37 36 1.24 
1,040 900 595 325 14,1 5. 25 2.14 1, 42 
1) Set oie a ee L022 882 575 307 14,5 dado 5 fil 1.38 
1,040 900 625 275 15.9 10, 54 - 00 ES Y 
1,035 895 575 320 16.3 10. 00 5 7il 1,31 
WA See eis tee = 1,037 897 572 325 16. 2 10.5 - 48 Wey) 
1,035 895 600 295 16.8 11. 94 . 00 1,29 
1,040 900 575 325 22.0 9. 75 5. 94 . 93 
5 te Se es eee es 1,035 895 580 315 21.4 12.5 5. 23 1.19 
1,035 895 595 300 21.9 17. 90 Sali . 80 
40 { 1,065 925 530 395 25.5 17. 75 3. 56 79 
Treats). etht 1,05 910 570 340 25.9 22.10 . 00 88 
1,060 920 475 445 31.4 13. 00 9. 97 76 
BUS eee Soe ets. | 1,047 907 507 400 30. 2 21.75 Sp 79 
1,065 925 510 415 31.6 29. 22 00 76 
Green gage plums, 
30° sirup: 
400 grams. <2... - 982 842 335 507 24.0 12.0 8.77 . 67 
450 grams........ 997 857 402 455 22.5 11,2 9. 03 . 83 
500 grams........ 1,060 920 430 490 22.8 12.5 5. 22 . 84 
550 grams 1l.._.... 1,03 890 375 575 21.0 9.0 8. 82 98 
. 1 Fruit, crushed, would not drain properly. 
79258°—Bull. 196154 
