I think making it OUT of your bread machine will help...a lot!
with all that "heavy" stuff....and only 1 T yeast....it will take a long time to rise and the machine doesn't allow for that....
Try it again, by hand....and watch it as it rises....may take up to 4 hours...maybe more.
Linda C

I'd say there are a couple of things that might help.

Add the sugar when you dissolve the yeast--it needs nourishment to get going.

I'd give it 2 rises--one before shaping, one after. The bread machine isn't going to work for a long-rise bread like this, so yes, I agree that you will almost surely get better results if you made it without using the bread machine. And I wouldn't bake it until the BREAD said it was ready (not the clock--rising times are just estimates, you really have to go by the texture, feel, look of the bread.)

Do you think so, really? The recipe calls for one rise, not two. I might add more yeast and try it again. I only have a toaster/convection oven right now. I'll report back later today.

What is the function of the vinegar?

About 15% of the volume of dry ingredients is the dead weight of the soy flour. By dead weight I mean that it has no gluten and so can't develop a structure that will support the rise; it's weight that has to be carried along. That isn't an impossible amount but it's sure not helping. If you cut it down to a quarter of a cup, that recipe would work better.

The quarter-cup of gluten flour (is that pure gluten or a high-gluten flour?) has some pitfalls too. Yes, it will aid the structure, but that gluten has to be developed, and according to some baking experts, will have to be kneaded longer. I don't know if bread machine kneading is more or less than you'd do by hand. If you do it by hand you'll have a feel for how elastic the gluten is getting. You could start in a machine and then continue by hand. You don't want the soft, sort of relaxed feel that you might want for some of the hearth breads people are baking. The yeast is more than enough.

Here's a high-protein bread I made years ago that used some soy flour. It wasn't bad, definitely not a brick.

Cornell Bread

This widely known Cornell bread is high in protein with its nutritionally enriched combination of flours. It was created in the 1940s to act as a staple in the low-cost diets of the days of war rationing. The nutritional merits are important, but what fueled the popularity of the Cornell Formula was its pleasing taste. The Cornell Bread recipe was developed by Cornell professor, Dr. Clive M. McCay (see below for details).
Cornell Formula White Bread

3 cups warm water
2 packages active dry yeast
2 tablespoons honey or sugar
3 teaspoons salt
2 tablespoons vegetable oil
6 cups unbleached flour
1/2 cup full-fat soy flour
3/4 cup nonfat dry milk
3 tablespoons wheat germ

1. In a large mixing bowl, dissolve yeast in warm water. Stir in honey, salt, and oil.

2. Combine three cups of the unbleached flour with the soy flour, dry milk, and wheat germ; add to yeast mixture. Add more flour, 1/2 cup at a time, to make dough stuff enough to knead easily.

3. Turn dough onto a lightly floured board. Knead about ten minutes or until smooth and elastic, adding flour as needed to keep the dough from sticking.

4. Place dough in a lightly oiled bowl, turning to oil the top. Cover with a clean towel and let rise in a warm place until double; about one hour.

5. Punch dough down and turn onto lightly oiled board. Divide dough into three equal portions and shape each into a loaf. Place in greased 8x4- inch pans. Cover with a clean towel and let rise until double; about one hour.

6. Preheat oven to 400. Bake 30 to 35 minutes, or until bread sounds hollow when tapped. Remove from pan and cool on wire rack.

YIELD: Three 8x4 inch loaves.

I much prefer hand formed bread. And have been baking bread since I was 12. I do have a fell for it which is lost in the machine, of course. I was being lazy to make it in the machine. I wondered about the soy flour and assumed the large amount of gluten flour was to compensate for the dearth of gluten in the soy.

I'm going to give it another go and be more patient.

I saw the Cornell recipe, too. It does look good. Can I sub white whole wheat in place of the AP? I NEED that fiber!

I agree, the high percentage of soy flour in that recipe is one of the culprits. I've made the Cornell Triple Formula bread for years and it always turns out well: into a one-cup measuring cup put 1 TB dried milk, 1 TB wheat germ and 1 TB soy flour. Fill the cup with flour - unbleached or whole wheat. Do this for each cup of flour that your recipe calls for and you will have nutritionally improved bread.

You only have 2 1/4 cups flour/soy/gluten in the recipe. One tablespoon of yeast is way more than necessary, but the large portion of soy flour is what is preventing the bread from rising. You need more wheat flour and less soy.

Cloudy is right - you need more kneading to develop the gluten than a bread machine will do. Try making your recipe with some modifications by hand, kneading for at least 10-15 minutes.

I would try half whole wheat flour and half unbleached white white. Or thereabouts. You could certainly use all ww, though.
With any whole-wheat bread, you get better results if you let the wet dough sit around a little while after you've added all the whole wheat flour and the liquid. Then, after the bran has absorbed some of the water, go ahead and add enough flour to knead the dough. Otherwise the bran often absorbs too much water from the dough.

I have a modified version of the Cornell recipe rising on the counter now. It seems to be rising nicely. If it also tastes good, I'll post a pic and the recipe.

It's much better than the previous loaves but not wonderful. I think the soy flour has a bitterness to it. Something is off. I'll keep tinkering. I ate a hot slice, maybe cooled and toasted it will be better.

Eileen:
Why don't you make a good tasting Bread that you like, and eat less???
How do you expect to get big and strong. LOL
LOU

The Cornell type breads with the soy flour were developed to add extra nutrients. If your only concern is the low carb diet, then all you need to pay attention to is that the bread is whole grain, whether that's whole wheat, rye, etc. It's still carbs, but much more healthy carbs that the body absorbs very differently from white flour carbs. You don't have to use the soy flour.

But is it the soy flour that makes it taste bitter? And was the vinegar in the Scarsdale recipe there to offset the bitterness? Or maybe it was the wheat germ? I got it from the bin at the grocery store natural foods section. It smells maybe old. Wheat germ goes quickly, I know. I'll leave out the wheat germ and use whole wheat flour. I'm on a mission!

Rancid wheat germ is bitter...nasty! Fresh wheat germ is yummy! Taste soem before you cook with it again.
Soy flour tastes "funny" for want of a better word...I find that I can't add more than 2T per cup of other flour before it tastes funny...

Yup, I'm thinking it's the wheat germ. This loaf still tastes bitter this morning. The dog will have it for breakfast. This wheat germ smells a little linseed oily and tastes the same. Not like something I want to eat. I usually buy the Kretschmer stuff in a jar.

I think soy flour has a bitter edge to it too. I know a lot of people don't think it's prominent, but I always can tell when a dish has any kind of raw soy product. I wonder if there's a way to overcome that tendency? I found this online; I have no idea if it's valid, though:

"Soy Flour, when not fully cooked will taste bitter. To avoid this toast it in a dry pan over medium heat until it's slightly darker and smells nutty. If you want to toast a large amount of flour to have on hand spread it in a cookie sheet with a lip and toast in a 250 degree oven for about an hour, stirring every fifteen minutes. As long as you have the oven going you can place a cookie sheet of soy flour on each rack."

I also found this suggestion. Again, I'm not sure if this info is correct, but it is interesting:

"Soy flour (ground uncooked soybeans) has a strong soy taste and will make nasty brownies. Soy POWDER, made from cooked soybeans, has little or no aftertaste."

Qyuote" Home-baked bread is denser than commercial so cut thin slices, then toast. Keep in refrigerator."

I think right in the recipe they're telling you in a nice way to expect bricks LOL

My adapted Cornell recipe wasn't brick like, firm, but tender. It took for freaking ever to rise, though. I'm pretty sure the wheat germ is the problem as the Scarsdale recipe had more soy flour to wheat flour and didn't taste bitter. I'm going to try again today with fresh wheat germ.

My newest loaf is much better. Yes, it was the wheat germ that made it bitter. This loaf wasn't perfect and I still need to adjust proportions and sweetness. I also over proofed it, thinking it would take longer than it did. I went to the gym! I'd like a little more sweetness than it has right now. I used whole wheat as well as white whole wheat and some AP.

I'm going to keep working at it. This loaf is at least edible. Snowy, the Yellow lab in residence, had the previous loaf as a treat. I just hope it doesn't give her awful gas!