So far, those eager to bake low-carb have found a reasonable sugar
substitute (Splenda) though it does not do much of what sugar does
(chiefly it lacks gelling function). The insuperable problem is flour.
The following flour substitutes have been tried:

Soy flour - tastes beastly; requires wildly strong counter-flavour to
block taste. Little gluten. Browns very quickly.

Vital wheat gluten: very, very strong, so creates elastic or rubbery
texture

Ground seeds: used alone, no gluten. Very heavy and dense (see nuts,
below). Flaxseeds have a texture some describe as 'like snot'.

Soy Protein Powder: no gluten. Dense texture, and somewhat gritty.

Whey protein powder: carbier, and see above. hard to get in flavourless
forms, and flavoured forms taste very aritficial.

Ground nuts: make baked goods dense and heavy

Coarse bran: used alone, the result is heavy and damp. Too many carbs
for some.

A mixture of the above: I have made acceptable bread from a mix of VWG,
ground flaxseed, whey powder and coarse bran. The gluten prevents the
other ingredients from being heavy and the whey tenderises the dough so
the gluten isn't too rubbery.

Generally, the following kinds of baked goods work reasonably well:

Biscotti and cantucci, brutti mar buoni and the like
Macaroons
Wholegrain-style breads
Custards and cheesecakes (though Splenda will make cheesecake 'weep')

What doesn't work at all in my experience is cake, biscuits, muffins,
anything that requires lightness. Yes, I've made the recipes around -
many, many of them - the results were - well, let's say nuggety. There
is no low-carb equivalent of cake flour, as all the above are either
hard or utterly gluten free. But it must theoretically be possible to
combine VWG and one of the gluten-free items above in such proportions
that they equal cake flour. Has anyone had any luck in doing so?
--
Jane Lumley