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♦ Liquid lost from jars during processing is caused by:
(1) packing the jars too solidly or overfilling them;
(2) an insufficient exhaust period;
(3) air being exhausted too vigorously during the 10-minute venting period;
(4) a variation or sudden reduction of pressure in the canner; or
(5) failing to tighten the screw bands according to the manufacturer’s
directions.
If liquid is lost during processing, do not open the jar to replace the liquid.
Loss of liquid will not cause spoilage, but the food above the liquid will
discolour. If at least half of the liquid is gone, place the jar in the refrigerator
and use the food within 3 days.
♦ Food spoilage or jars not sealing is caused by:
(1) failing to follow exact timetables and recipes;
(2) failing to wipe the sealing edge of the jar clean before placing the lid on;
(3) having foods, seeds, or grease lodged between the lid and the jar;
(4) using jars which are nicked, cracked, or have sharp sealing edges;
(5) failing to tighten screw bands according to the manufacturer’s
directions; or
(6) turning the jars upside down while they are cooling and sealing.
If a jar does not seal, refrigerate it and use the food within 3 days. Otherwise,
reprocess or freeze the food within 24 hours. Freeze or repack using new
lids. Reprocess for the full recommended processing time.
♦ Flat sour, a type of food spoilage, is caused by canning overripe food or
allowing precooked food to stand in the jar too long before processing. It
may be prevented by using fresh food and properly processing, cooling, and
storing food. Flat sour shows no indication of spoilage until the jar is opened.
Discard the contents.
♦ The black deposit sometimes found on the underside of a lid is caused by
tannins in the food or hydrogen sulfide liberated from the food by the heat of
processing. This does not indicate spoilage.
♦ Mold can form only in the presence of air. Therefore, the jars are not sealed
if mold is present. Discard the contents.
01785 4033-017A CUL English weighted gauge induction canner.indd 18
01785 4033-017A CUL English weighted gauge induction canner.indd 18
12/13/19 10:34 AM
12/13/19 10:34 AM