Identifying micro contamination in blown products of milk (UHT)

Hi Guys!

does anyone here have expertise in Tetra Pak packaging and related issues?

We have blown products of Milk filled in Tetra Pak (UHT) produced within one minute after the event stoppage. When we did direct microscopy we found bacteria in curd milk thus there was a contamination.

We check all - the packaging, fillers, swab after CIP, and the products after that "one-minute". Surprisingly, all were fine and met the limits. 

What else do you think guys the other problem?

thanks!

Hi, Rener.

Coming from same operation, here are some questions that I might share with you.

1. Why did you stop and how long did you stop? Are the factors to maintain sterility still intact during this stoppage?

2. How many packaging you tested for leaks and how many packaging test did you make? Usually its 4 type. Since you are also using Tetra I assume you have the same number of type of packaging check.

3. For the 1 minute, how did you establish that sampling or disposal window? for the event sample, how long from the splicing did the curdling occurred? You may have too small window (but 1 minute definitely is long). You may want to check your splicing practice (for GMP consideration).

4. How is the overpressure for both the filling machine and your room? Your room should have higher pressure relative to other rooms and your filler must have overpressure relative to your filling filling room.

5. How is the concentration of your peroxide? And other related factors for packaging sterility (e.g. air slice etc).

6. Is the packaging still available for the sample that you have curdling? have you checked for pinholes? For the microbial growth, you may want to ID just to help you with the cause.

7. Normally if it is event sample, I would not go for CIP, depending if there is CIP just before the event. Usually there is a pattern in the batch if it is based on CIP but since you only say after the event, I will not go there.

8. If all seems ok during your investigation and normally this would be the last thing I would really go to, how is the sampled handled or stacked with other samples before analysis?

Thanks