My sourdough is SO sour....

I don't have experience with that particular starter but most starters become progressively more sour with time after you feed them (add fresh flour) as the lactobacilli do their work. My decoder ring says you probably bought your New Zealand Rye starter from sourdo.com, not from Ed Wood who I suspect you've never met face to face.

It really doesn't matter how the dough smells so much as how it tastes, how well the dough rises, and how the bread tastes after it's baked.  With some experience you can guesstimate whether a culture is active by taking a little taste of the culture and looking at it.  Bubbly is good, moderately sour but not so sour as to inhibit the yeast is good. 

If you're making rye bread, sourness is probably pretty important because suppposedly acidity moderates enzymes in the rye that would otherwise interfere with the rise.  What IS this "World Bread" you're making?

Your bread probably turned out really sour because you let the dough sit for so long. The longer it sits, the more acid the bacteria produce, which increases the sourness. If you think your bread is turning out too sour, try to reduce the time you let the pre-ferment and dough sit.

Taste, of course, is subjective. There's nothing wrong with a sour loaf if you like the taste, but don't think that the bread is supposed to taste sour just because it's sourdough. The best tasting sourdough I've made you probably wouldn't be able to guess it was a sourdough loaf. If you want to taste some great sourdough breads, find La Brea Bakery breads. You may be able to find those in a local supermarket with a bakery. Costco also sells them (at least they do in So. Cal.).

if you want a sourdough with that distinctive sour tang, ideally, there will be a hint of the sourness that blends with the other flavors to give you a nice balance. If the bread is too sour, that's all you taste. In my limited time making bread, I've managed to end up with both types of loaves, and I definitely prefer the more balanced loaf.

There are various tricks for reducing acidity/sourness. 

- Using starter that you refresh/feed at more frequent intervals, discarding more of the old starter with each feeding

- reducing temperatures (warmer temperatures reportedly promote sourness) by turning down the thermostat in your house or stashing dough in the fridge

- choosing a different sourdough culture (the Finland culture from sourdo.com seems to be low acid).

- throwing in some store-bought yeast in the final dough to boost the rise and give the lactobacilli less time to produce acidity

- adding a little sugar to the final dough to bump up the yeast's activity a bit

ph_kosel gives some good advice yet I say the only benchmark you need consider is who is eating the bread. My degree of sour is what my family and I like. A professional baker will try to satisfy his customers. Try using less chef in your build. One french method uses hot water in the build to reduce acidity. Haven't tried it. Don't get hung up on what a formula calls for. You're not baking under the same conditions,or the using same flour as the baker whose formula you're following. Though sometimes frustrating, I keep baking because it's a constant learning experience. Take a lot of notes, try taking the temp of the dough at different stages, constantly feel the dough at different stages, make small changes to see what happens. Let the dough tell you what it needs. Have fun.

Jim

I checked and found a Recipe for "world bread" in Classic Sourdoughs - a Home Bakers Handbook by Ed Wood.

It's a white flour sourdough made with made with milk and butter.  Mayhaps the "sour" that Mr. Gringogigante smelled was sour milk.