Help me understand this OG math

I’m brewing the NB Belgian Strong extract kit soon and I thought for fun I’d run the recipe through Hopville. I was surprised to see the OG estimates differ so much. NB predicts 1.081 and Hopville 1.074. That’s about 1% ABV, not exactly a rounding error.

7lb Golden Light DME @ 43ppg
2lb Clear Candi Sugar @ 32ppg
Steeping of 1/4lb each of Belgian Caramel Pils and Belgian Biscuit Malt.

As far as I can research, the ppg values above (from Hopville) are accurate. Hopville only estimates one additional point from the steeping.

Any idea where the difference lies?

The difference is in the values used by NB for the DME and the sugar, plus perhaps they assumed a little more contribution from the 0.5 lb of steeping grains.

Ok…but I thought the ppg values for Breiss DME and Candi Sugar were fairly well understood?
Also, I can understand some efficiency assumption differences for the steep, but this recipe only has half a pound of grain. Shouldn’t make that much difference.

Hopville assumes 43ppg for the DME and 32ppg for the sugar, which is in line with what I found elsewhere.

I had stopped measuring my OGs since I was lead to believe as long as you topped up to 5 gallons you would hit what the kit estimated. I’m scheduled to brew this guy next weekend so I guess I’ll see what I end up with (and yes, I’ll shake the carboy until my arms fall off before sampling :slight_smile: )