Scientists classify foods based on particular characteristics. Foods such as vegetables, milk, meat, and seafood are considered
“low-acid foods” because they have naturally low acid levels. The
acidity of a food can relate to its safety and should be a concern for food
Low-acid foods have pH (acid) values greater than 4.6 and water
activity (aw) greater than 0.85. Low-acid foods are important
because when they are processed and placed into sealed/air-tight containers such
as cans, pouches, or jars, and not stored under temperature control, they can
allow the growth of Clostridium botulinum, the organism that causes
The foods can be made safely when processed with proper heat or
acidification. Low-acid food products must receive prior
evaluation and approval from the Food and Drug Branch (FDB) to determine the
need or acidification or thermal processing. Certain food
products, such as herbs or vegetables in olive oil, can only be manufactured
safely by the addition of an acidifying agent.
Low-acid foods are regulated by FDB’s Cannery Inspection
Program. Low-acid food processors (canneries) must comply with
California and federal requirements. Canneries are required to operate under a
valid Cannery License that is renewed every two years. Canneries engaged in
general food processing activities must also operate under a valid Processed
Food Registration (PFR). Canneries that need a PFR are not
required to pay both license fees, however canneries must pay costs associated
with cannery inspections.
Information about the PFR requirements can be found on the PFR website.
Information about the requirements for operating a cannery can be found