Indeed, we will use 2541g. The products we intend to export are clearly LACF and one or two that are borderline acidified. However, they all are processed, sterilized (overkill) and aseptically filled in the same manner like I described. Thanks for your input. I will start up discussions with our Process Authority. My main aim is to steer away from FSMA as much as possible as it does not (fully) apply to aseptic LACF.
I do have one concern: if we file the borderline products as LACF and the FDA comes back to us and states that it has to be filed as acidified we have a major delay in product launch. Can I get your view on this one more time....? I appreciate that I can finally ask these things with someone actually based in the US :-)
In summary, you would still use water activity and pH to determine your first course of action when making the product. If when formulating, the water activity is less than 0.85, you don't need to file. However if it is greater than 0.85, you would look at your pH. If it is less than or equal to 4.6 naturally, you don't need to file. If it is above 4.6, then you need to file. Based on the information given, your water activity is probably going to be fairly high, so then you would look at your pH. Your pH is borderline, so then you would need to file (regardless of whether it will be critical to the process).
After that point, you would be looking at the different FDA Forms. One form is for the retort method, one form is for the acidified method (acidifying a food and adjusting fill temperatures), water activity/formulation control method (adding an ingredient to bind to water), and then the form for low acid aseptic systems. You're using UHT and filling into tetra cartons, which tells me: 1. It isn't the retort method. 2. You aren't adding any acid to lower the pH, so this wouldn't be the acidified method. 3. You're not adding any ingredients specifically to bind to water (at least that I'm aware of). Therefore, the best choice you have and what looks to be suited to your product is the form 2541g for low acid aseptic systems.
Our process is simply acidified foods. We adjust pH to a certain level, and fill at a certain temperature. I can't necessarily comment to the low acid aseptic systems, but from a process of elimination standpoint, form 2541g is what I would suggest. Hopefully there are some others on here that have more experience with UHT and can confirm. You could also go about directly contacting the LACF group at the FDA to find out exactly what form you should use, if you have significant time constraints.
I hope this helps!