5 replies to this topic

[Jackson Tsang]

Any hazard in risk assessment?
Suppose it is direct food contact. I would like to add in the assessment but can't think of any

[Charles.C]

Any hazard in risk assessment?
Suppose it is direct food contact. I would like to add in the assessment but can't think of any

 

Dear jackson Tsang,

 

A few CPB possibilities are -

 

chemical cross-contamination from the Nitrogen

physical / chemical / microbiological cross-contamination from the system / personnel / environment

microbial growth of pathogens in whatever you are processing

 

Rgds / Charles.C

[Jackson Tsang]

Many thanks. Charles

[MWidra]

There is non-food grade liquid nitrogen as well as food-grade.  The risks of using non-food grade would be that any minute impurities could be a hazard, either chemical or biological, to the food.  To remove that risk would be to only use food-grade liquid nitrogen.  Since any pathogen that happens to be in the liquid nitrogen will be perfectly preserved and would start growing once it thawed out, you would need to be careful to use the food-grade quality.

 

Also, please remember that there is a very important risk to your employees when you use liquid nitrogen.  The expansion rate when liquid nitrogen warms up and turns into a gas is 694 to 1, so there is a great risk of explosions as the nitrogen is being contained and used.  Never put it into a vessel that is not approved for liquid nitrogen, and if there is a safety valve, make sure that it is never turned off.  There are some very graphic photos of tanks that blew apart when the safety valve was shut off, I guess to stop the loss of material.  There always needs to be a place where the gas will bleed out of the vessel or system, for safety's sake.

[Dr Vu]

_{Do u get CoA for the nitrogen?}

 

_{here is  possible hazards as per our CFIA}

 

 

_{GAS FLUSHING
Type of Hazard                     Name of Hazard
B                          Pathogen growth due to improper amount of CO2
B                         Growth of pathogens due to inappropriate vacuum of air volume /
pressure of gas (e.g.: CO2) in Modified Atmosphere Packaging (MAP)}

 

_{C                        Chemical contamination due to use wrong gas}

[Charles.C]

Dear Jackson Tsang,

 

Perhaps i should have added that -

 

Assuming you are using (a) an approved supplier of, food contact intended, Liquid nitrogen, (b) that yr prerequisite hygiene SSOPs are properly implemented, © that yr freezing time is adequately rapid (which it probably is) -

 

then all the hazards i mentioned should be insignificant.

 

Rgds / Charles.C