Affects of topping up on flavour

[Noetikon]

I recently brewed a robust porter (AG batch). I ended up boiling off a lot more than I hoped, and so to hit my OG target I topped it off with 0.5 gallons of water (using Beersmith's dilution tool). My question is: What affect, if any, does topping off have on flavour?

After primary fermentation the beer was rather bland. But I don't know if this was because I topped up (effectively diluting) the wort or because of the recipe itself. Any thoughts?

[brewinhard]

Topping off will dilute the gravity and the hop bitterness and flavor. When you topped off did you reach your desired original gravity per the recipe? If so, then you should have maintained the malt to hop balance you were shooting for in the first place.

[Noetikon]

Topping off will dilute the gravity and the hop bitterness and flavor. When you topped off did you reach your desired original gravity per the recipe? If so, then you should have maintained the malt to hop balance you were shooting for in the first place.

I topped up to hit my target gravity of 1.061, which was the original OG in the recipe. This helps me narrow down the source of the problem.

[Ozwald]

Which means that your hops are going to be a little light, but with a robust porter & only half a gallon of water you probably won't even notice.