adding sugar to your fermenting wort...

"Chemically" it's exactly the same. You're producing alcohol and CO2. Just like when you bottle prime. The difference is that the CO2 in your fermenter can equilibrate with the atmosphere over time, whereas in the bottle it's trapped.

 

Some add sugar to the boil. Same concept, it's just to add an element of sanitation. I don't have a personal preference most of the time and I'm willing to add it to a 5%+ beer just as table sugar from the jar. I've done this with maybe 5 batches. No issues yet.

 

Adding sugar a few days into the primary fermentation will boost ABV / lower FG.

 

Is that inherently different from adding during the boil? I have my own ideas, but what say you?

 

Nope. The same.

To the OP, the difference is in the mass being used. 5 oz of sugar is about 42*5/16 = 13 points of fermentables added to a 5 gallon batch, or less than 3 pts added to your OG, just outside the margin of error (which I consider on a homebrew hydrometers +/-2)

 

One of the guys at the LHBS suggested I add belgian candi sugar to my saison a few days after fermentation begins because the sugar is like junk food to yeast. They will consume the easiest to digest sugars first and then could 'crap out' on the more complex sugars.

 

While that is true, it is generally only a concern if you have a large proportion to simple sugars in a higher gravity wort, something like a BGSA or a tripel. The yeast won't get "lazy" from only 5% addition in a 1.050 wort.

 

Terrible analogy. Who eats a grew big meal and then has room for junk food? I also think your shop guy and everyone else who repeats this with no evidence are off their collective rocker. If you're using a normal amount of sugar, say up to 20%, it wil not effect the quality of your fermentation, at least not in my experience. Duvel, Gavroche, and other highly chaptalized commercial beers all add the sugar(s) to the kettle. The only commercial beers that are further chaptalized after the initial fermentation are bíere de brut and other high kinda stuff that exceed 20-25% fermentable from simple sugar.

 

An ever increasing number of Americans? I do agree though that with reasonable simple sugar proportions there's no need to add late. I'd say his analogy was fine, but reflected a condition not encountered with most recipes.

 

With simple sugars (which really don't contribute flavors), it would be about the same either way. Some sugar sources (like honey) that do contribute flavors/aromas would do better added to the fermenter than the boil. If the Candi Sugar you're talking about is a dark sugar, it might be better to add to the fermenter.

 

Jamil also suggested adding sugar late on the Belgian Tripel episode of CYBI. I don't have the link handy but I believe his specific recommendation was to add the sugar when attenuation was 3/4 complete.

I tried that technique in my last tripel (warning: n=1) and was disappointed with the result. All of the beautiful Wy3787 aromas disappeared overnight and only ethyl acetate remained. In my case I reserved 2.5 lbs of cane sugar and 0.5 gallons of water from my original recipe. After reaching 3/4 of my expected FG, I boiled the sugar and water for 20 mins, cooled to fermenter temp, and added to the fermenter. I tried not to splash, but my guess is that oxygen got into the beer during this transfer, and since the yeast were past their growth phase they could not clear it.

 

Used to wonder about that myself...too.

Consider it a 100% fermentable fivehourenergy booster shot aimed directly at lowering FG.

 

Sugar doesn't caramelize during a long boil unless you get your wort down to a gooey paste and raise the temperature of that we'll past boiling. I have no clue where people get this misconception from. You do get melanoidin production during long hard boils, but not caramelizatikn!

 

I almost posted the same comment, but he did say caramel 'flavour' (not necessarily caramel itself). Melanoidins can taste caramelly.

 

Fair enough, but the exact same comment? Man I type poorly on my phone