What are you using to measure blood sugars? Some meters are sensitive to some of the sugar alcohols such as Malitol, Sorbitol etc Some meat products have added Malitol. I am aware of some brands of faggots that are guilty. Also, it is often added to gravies. I had this problem as a T2D where pork sausages from one supermarket spiked me, but when I changed to a different and cheaper shop, the problem resolved. Same with the faggots - supermarket ones spike, butcher made ones do not. recently a portion of sliced roast beef in gravy spiked me. Normally I can eat a full on beef curry, full of diced beef, without any problem.
Also beware of garden peas in the frozen sections. These are often doctored to make them tender sweet and kiddy suitable. Ditto sweet corn. again, my choice of supermarket nowadays seems offer undoctored.
But I am T2D on orals, so my experience may not read across to yours.