Good day all! I work at a food packaging manufacturing facility. We thermoform plastics and use compressed air to remove the items from the mold. Compressed air testing is performed in house annually per SQF requirements.
We have been running into issues with several contaminated blind plate (before and after) results for the past few years. Aseptic technique was questioned, so we had someone internal who was more experienced perform testing (he had successful results in the past) and he too had contaminated sterility blanks in his test results. The media is provided to us by the testing company each time we perform testing. The sterility blank control is never affected.
I am wondering if it is the general environment that is contaminating the blanks. Our facility is not climate controlled and we are currently in summer in central Florida. There are lots of fans blowing in the facility and the humidity is high. With this said, the highest number we've gotten on a blind plate is 25 cfu/plate TBC on the suspect testing. All others were 1-4 TBC. Much lower, but I know, not acceptable.
Could anyone provide some guidance? I feel that the issue is (1) time of year, so maybe we try winter? or (2) just bad technique and we have someone else give it a try. Maybe a vinyl cube (like a mini photo studio) when handling blanks to prevent outside air contamination??
Thanks in advance!
