I don’t know of any food to prevent bloat. You haven’t mentioned the breed or weight of your dog. If you want to be absolutely sure do a gastropexy. I know many American Akita owners who do the procedure and with some of the monthly allowance you would be willing to pay for food, the procedure would be well worth it.
You may know that bloat is extremely painful. In horses, they call it colic.
https://vcahospitals.com/know-your-pet/gastropexy
About foods…
https://www.petmd.com/blogs/nutritionnuggets/jcoates/2012/may/how_to_feed_dogs_at_risk_for_gdv-16454
Years ago, Dr Larry Glickman at Purdue did a health survey with Akitas and probably other breeds. One result of that stuudy was that dogs of a certain stature were 200 times more likely to have bloat with raised bowls, water or food.
https://www.vin.com/apputil/content/defaultadv1.aspx?pId=11165&meta=Generic&id=3848657
I have a Shiba now and I am cautious, though I haven’t had a dog bloat.
I hope you’ll find the right solution for your dog and that it makes you rest easier.
Keep up with the research.
Best, B
