============+=============================
| Per cent of solids.
Temperature,+----+----+----+----+----+----
° C. | 10 | 15 | 20 | 25 | 30 | 40
------------+----+----+----+----+----+----
| To be subtracted
+----+----+----+----+----+----
20 |0.55|0.56|0.57|0.58|0.60|0.62
21 | .48| .49| .50| .51| .52| .54
22 | .42| .42| .42| .44| .45| .47
23 | .34| .35| .36| .37| .38| .39
24 | .27| .28| .28| .29| .30| .31
25 | .21| .21| .22| .22| .23| .23
26 | .13| .14| .14| .15| .15| .16
27 | .07| .07| .07| .07| .08| .08
+----+----+----+----+----+----
| To be added
+----+----+----+----+----+----
29 |0.07|0.07|0.07|0.07|0.08|0.08
30 | .13| .14| .14| .14| .15| .15
31 | .21| .21| .22| .22| .23| .23
32 | .27| .28| .28| .29| .30| .31
33 | .34| .35| .36| .37| .38| .39
34 | .42| .42| .43| .44| .45| .47
35 | .48| .49| .50| .51| .52| .54
------------+----+----+----+----+----+----
Whether or not ketchup should be processed after filling into bottles
depends on the conditions under which it is bottled. If the bottled
product can be sealed at 180° F. or better a process is not necessary
and is an unnecessary expense and waste of time, besides it may
injure the color of the product. With the modern type of equipment
it is possible to fill the bottles at a temperature which obviates
sterilization. Care must be taken that the temperature of the ketchup
in the receiving tank feeding the filler does not fall too low. Care
must also be avoided in order not to fill the ketchup at too high a
temperature as it results in excessive shrinkage of the contents.
For ketchup filled at relatively low temperature a process should be
used. The process necessary will depend upon the temperature at which
the ketchup is filled and on the time that may elapse between filling
and processing. Sanitary conditions of the factory and equipment are
exceedingly important not only in relation to ease of sterilization but
also in securing a product of good quality.
In stacking ketchup it is best to stack the bottles upside down. This
tends to prevent darkening of the ketchup in the neck of bottle, a
condition known as “black neck.” It has been our experience that
wherever this condition has occurred it is due to leakage of air into
the bottles. Stacking bottles in this way undoubtedly keeps the cork of
the cap moist and makes the seal more effective.