Flaked rye vs. rye malt

LHBS is out of rye malt (and other grains), and having trouble with their supplier. I don't want to order a huge order to make online shopping worth the $. How does the taste of rye malt vs. flaked rye compare? Local health food store caries flakes. I am making a Belgain roggenbier targeting abour 35% rye, 10% pils, 50% Munich, 5% specialty 1.048. It will be a starter for a strong Belgain that I want to get brewing soon. I am brewing next weekend. Any input on flavor or other characteristics that differ would be appreciated.

I would guess that the flavor wouldn't be too terribly different if you were using it as 10% or less of the grist. However, the results will likely differ wildly if you substitute flakes for malted grain as 35% of your grain bill. Malted rye tends to have a fairly high diastatic power, but flaked rye has none. Munich malt has enough at least enough diastatic power to convert itself, but I doubt you'll get very complete conversion if you count on it as the only real source of enzymes. Flakes tend to be high in protein, so you probably want to avoid using them in large quantities like you are suggesting. Also, using a large amount of flaked grain like that may increase the likelihood of a stuck sparge (though even malted rye has a propensity for sticking a mash anyway).

You are going to have to add some enzymes or boost the percentage of Pils and do a long mash. A protein rest would also be a good idea.