SC - flour, sugar and fat in the medieval diet?

[Decker, Terry D.]

Despite Jacob's assertion that flour was not bleached, xanthophyll, the
carotenoid pigment which gives freshly milled flour a light yellow tint,
oxidizes naturally as flour ages.  Aging flour improves the quality of the
gluten.  If medieval flour was aged, then it was bleached.  What Jacob is
probably referring to is chemical "bleaching," which are actually techniques
to quickly "age" the flour.

I have a little difficulty with medieval flour being higher in fiber
components than modern flour because of the milling technology, especially
if you are talking stone milling.  The grain is the same, so the ratio of
nutritive to non-nutritive components is the same.  The grain is crushed to
a powder between two stones.  The percentage of the grain crushed to powder
depends upon the hardness and the closeness of the stones.  Optimal
extraction of flour from grain with a stone mill is about 85 percent, and
average extraction was about 75 percent (if 14 pounds of "chisel" per bushel
is any indicator).  We can get better extraction rates from stone milling
now with man-made stones and laser dressing, but those don't predate Jacob's
work. 

Jacob may have been comparing medieval stone milling with modern roller
milling.  Roller milling has a much higher extraction rate and provides more
useable flour for the same amount of grain.  In the case of wheat, it also
strips the vitamin rich germ and actually reduces the nutrional value of the
flour when compared to stone ground flour.

The cheapest brown breads were made from unbolted flour, which means the
bran and the large particles of unground grain remained in the bread.
Almost all modern flour is sieved, which leaves more of the nutritive
components in the same volume of flour.  It may be this fact of which Jacob
was thinking when he made the comment, but the decision to bolt or not bolt
is an economic choice rather than poor quality technology.

Bear


> Um, _6,000 Years of Bread_ states that the flour was not bleached, but
> also claims that due to the poor quality of the milling 
> techologies, the
> flour of the middle ages tended to be very high in non-nutritive (i.e.
> fiber) components-- to the detriment of the health of those 
> who ate the
> breads made of poorer flour. It's peculiar to think of it in 
> this day and
> age, but apparently there was _too much_ fiber in medieval breads?
> 
>  -- 
> Jadwiga Zajaczkowa, mka Jennifer Heise