50 hours cold fermented bagels

RECIPE (1 bagel = 135 gr, raw) :
– Flour (14% protein) : 100%
– Water : 50%
– Brown sugar : 6%
– Salt : 2,5%
– IDY : 0,5%

3×10 minutes kneading with a 6,9L bowl-lift KitchenAid. 30 minutes rest. Shaped with rope and loop method. 2 hours proofing until float test positive. 50 hours cold ferment, covered. 20 minutes at room temp before boiling with a huge amount of diastatic barley/corn malted syrup (very bad decision, discussed below). Baked for 13 minutes at 220-240°C with steam and pizza stone.

I should have uncovered those on the last 6 hours to reduce the blisters, but I think it looks cool. Still not getting a huge oven spring with this recipe, I might add some dough improver or malt into the dough.

So I used a diastatic barley and corn malted syrup (see picture) in the boiling water, because I was out of regular barley malt syrup. I never used this diastatic syrup before, because I had bad results using some diastatic powder. I thought that the diastatic power (enzymes) would be inactivated by the boiling water. I was mistaken : The crust was WAY too chewy, almost impossible to chew. I am almost certain that it’s the syrup fault, as I never had this issue before. Huge bummer, because the bagels were good tastewise. I have 3 bottles of this syrup, and can’t figure how I’m going to use them (it’s supposed to go into the dough but I’m afraid to use it).

Do you guys have any insights regarding this issue ?