Wheat is a member of the grass family, and
if you like bread, cake, or crackers -- at least, the kind with wheat in them -- then
you’re already a fan. We use about 550 million metric tons of the
stuff a year. And these days, farmers and researchers are
noticing a rising demand for the return of different kinds of wheat -- partly because
specialty foods are becoming more popular, but also because they’d make our crops more
diverse. Specifically, people are interested in hulled
wheat, which is similar to the kinds of wheat that were grown in ancient times, like spelt,
emmer, and einkorn. Which is why, on January 13th, a research
team based out of the University of Hohenheim in Germany published a study comparing the
nutritional value of these ancient grains to the bread and durum wheats most people
eat today. And it turns out that if we want to start
producing more of those older kinds of wheat, we’ll probably need to develop them a bit. Hulled wheats are the ancestors of modern
wheat, but there’s at least one big difference: the grains of hulled wheats are encased in
a hard hull. That hull is made from glumes -- tough chaff
that protects the grains. It’s almost like the shell of a nut, but
it’s also really hard to get off. Modern bread and durum wheats, on the other
hand, are free-threshing wheats -- meaning, when you harvest them, the grain separates
from all the un-useful stuff pretty easily. Whereas the hulled spikelets of spelt, emmer,
and einkorn need to be dried, heated, or milled before you can break open the hulls and get
to the good stuff. So it’s not hard to see why we switched. Hulled wheat is just more work. But those hulls also protect the grain from
fungus and diseases. And hulled wheat can grow in less hospitable
climates, especially colder and less fertile mountain regions, where modern wheat can struggle. Plus, if some wheat-destroying superdisease
ever wipes out all of our modern wheat crops, it would be nice to have a backup plan or
two. So, to get the best possible data on these
older wheats compared to the newer ones, the team conducted field trials at four different
locations in Germany -- by growing 75 different varieties of wheat in each place. There were 15 varieties for each of the five
main types of wheat. Maybe unsurprisingly, the wheat varieties
we use today outperformed their ancient counterparts in pretty much every way. Grain yield, or “how much food we got out
of each plot,” was significantly higher for modern wheats. The yield for spelt, emmer, and einkorn were
37, 52, and 65% lower, respectively. The hulled wheats also grew about 30 centimeters
taller, which is not good. Taller wheat doesn’t mean more grain, because
the grain only grows on the top. But taller wheat runs a much higher risk of
breaking in a strong wind -- and the bent stalks are much more difficult to harvest. And that higher growth was after reducing
the amount of nitrogen-rich fertilizer given to the hulled wheats. Nitrogen-rich fertilizer being what makes
grass plants grow even taller. But how good is the grain they did get? Quality of wheat grain is partly determined
by its protein content. Nitrogen-rich fertilizers also improve the
plants’ protein yields, so it’s hard to compare the ancient wheats with the modern
wheats directly, since they didn’t receive the same amounts. But even with less fertilizer, the ancient
wheat actually contained more protein than our modern wheat. But not so fast, because not all protein is
created equal. Modern wheat has been bred to produce extremely
high quality protein. The protein in the hulled wheats didn’t
contain nearly as much gluten, which is the stuff that gives you all that energy after
biting off a hunk of bread. That said, alternative baking methods, and
more refined methods of farming, might improve the nutritional yield of hulled wheats. So: are hulled wheats better than modern wheat? Not really, but that isn’t too surprising. I mean, we switched to modern wheat for a
reason. But more options for delicious bread are nice,
and it’s likely that we can get better grain results with more practice. Selective breeding could someday give us shorter
plants with better protein and higher grain yields. So it’s probably worth developing these
ancient grains so we can bring them back on a larger scale. If you love SciShow and you want to share
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