Government regulations recommend the use of water activity

Government regulations recommend the use of water activity

Water activity is an important property. It predicts stability with respect to microbial growth, rates of deteriorative reaction, and physical properties. The U.S. Food and Drug Administration has incorporated water activity into safety regulations. These regulations detail specific requirements and practices to assure that products are produced under sanitary conditions and are pure, wholesome, and safe. Use the table below as a reference to U.S. government safety regulations that recommend the use of water activity.

AgencyProduct TypeReference No.Last UpdateDescription
FDAFoodFSMA Sec. 10312-5-16Describes preventative actions and risk based approach to safety, identifies the need to monitor preventative controls but does not mention water activity specifically
FDAFood21 CFR part 11712-5-16Outlines the practice for Hazard Analysis and Risk-Based preventative controls, including monitoring practices for testing such as water activity (does not specifically mention water activity)
FDAFood2013 Food Code2013Food code acts as a guide for determining hazards and preventative controls as part of new FSMA regulations. The definition of potentially hazardous foods, as found under "Time/Temperature Control for Safety Food" in the 2013 food code is based on aw and pH and uses Interaction Tables A and B
FDAFood21 CFR part 1135-1-16Thermally processed foods are described as being unsusceptible to bacterial growth if under 0.85, older code that is superseded by information in the 2013 food code
FDAFood21 CFR part 110.84-4-15GMP's outlined in this section under manufacturing operations (2) indicate that GMP's can be verified by monitoring water activity of the product to make sure it stays at safe levels
USDARTE MeatGeneric HACCP Model 102-5-05Identifies water activity as the appropriate way to monitor the drying process, specifically in place of moisture-protein ration
USDARTE MeatCompliance Guidline for Jerky (Including small plants)5-27-14Identifies the need to verify water activity to demonstrate the product meets the critical control point, and it recommends aw lower than 0.70 to control mold but also references the 0.85 level
USDARTE MeatCompliance Guidline for Control of Listeria1-2014Discusses options for making sure products are free of listeria including a post lethality treatment that prevents growth (water activity can be used for this purpose, but it doesn't specifically mention it)
USPPharmaUSP 11122006Provides justification for reduced microbial testing if low water activity (below 0.60)
USPPharmaUSP 515-1-16Method for Microbiological Testing now mentions that the testing refers to only those product with a water activity higher than 0.60 and references USP 1112
ICHPharmaQ6A Decision Tree 6 and 8Oct 1999References whether the product is inherently dry such that it will not support microbial growth, then provide scientific evidence of such and microbial limits testing may not be necessary
ISOCosmeticsISO 29616-1-2010Guidelines for the risk assessment and identification of microbiologically low risk products–many references to water activity
Table 1. Thirteen government safety regulations for food, pharma, and cosmetics.

Measure water activity in 5 minutes

Not a “quick mode” reading, but a direct measure of water activity to 0.003. No calibration, no approximation.