The Omega Horseshine is processed, has probiotics added also, will not go bad for two years, I believe.
I'm changing back to my all home cooked diet for my horses, now it makes sense with another horse. So I looked for bulk flax and found it, $32 for 50lbs, it's on order.
Boiling linseed is a royal mess! They need to be soaked overnight, then boiler for 2 hours. Gooey, sticky, Burns easily. Is used in a hot mash, or mixed into an already moist feed. In dry feed it remains a big blob which sticks to their teeth
I've done a lot of reading and all says no problem with the prussic acid.
It says grind it, a big bag full and keep it in the freezer so it doesn't go rancid.
I used to grind a day's worth and keep it in the fridge until feeding.