@Ulfhednar
Thanks for pointed out that I hadn't been clear in my previous post. You are right, I should have specified that there is no added preservatives in processed milk, however lactic acid only present in fermented milk and does not present in thermal-processed milk since it require LAB (Lactic Acid Bacteria) to convert lactose into lactic acid. Regarding Clostridium, while it is indeed can exist in thermal-processed milk, there's actually no case of natural food-borne botulism in thermal-processed milk have been reported. Furthermore, In my previous post I was thinking about heat-stable psychrotroph such as Pseudomonas fluorescens, Pseudomonas fragi, Micrococci, and Streptococi rather than Clostridium botulinum since it is more of a prevalent threat in bottled or canned food. Lastly, I agree with you about maintaining sanitary and hygiene as an important aspect for the safety and quality of a food products. I hope you are doing well on your work, especially in these tough time.
From: Aspiring food scientist
p.s.
Milk is naturally alkaline with pH around 6.5 to 6.7.
My uni is quite good tbh, our undergraduate program for Food Science and Technology have been certified by IFT and IUFoST 😁
Reference:
https://aem.asm.org/content/76/10/3293
https://www.uoguelph.ca/foodscience/book-page/ph-0#:~:text=The%20pH%20of%20milk%20at,range%20of%206.5%20to%206.7.