Momentum - The Magazine for Virginia Tech Mechanical Engineering Vol. 4 No. 2 Summer 2019 | Page 12

Before beer ever reaches a frosty
pint glass, the hops in it are often
dried. But it’s not so straightfor-
ward: once picked, hops may mildew
if not dried within 24 hours. Dried
too much, the quality deteriorates.
At worst, the essential oil-contain-
ing crop can spontaneously combust
during processing or storage.
A team of mechanical engineering
students have developed a low-cost
drying solution for the finicky crop
— and they’re providing it open
source to growers everywhere.
Hops driers, called oasts, are like
kilns for fresh, wet hop cones,
which are harvested from perennial
vining plants during a one-month
season late in the summer. While
large-scale farms often have access
to oasts capable of drying thousands
of pounds of hops, options for local
growers are slim.
As part of a larger hops grant,
the Virginia Agricultural Council
funded a mechanical engineering
senior design project at Virginia
Tech to develop an oast capable of
being powered with only 120 volts,
built using off-the-shelf materials,
and costing no more than $4,000.
Over the course of two semesters
and under the direction of principal
investigator Holly Scoggins and
research manager Daniel Jackson
of the School of Plant and Environ-
mental Sciences in the College of
Agriculture and Life Sciences, the
team designed, built, and tested an
oast capable of drying about 300
AN OAST FOR
LOCAL
BREWERS
ERICA
CORDER
COLLEGE OF
ENGINEERING
pounds of hops in 24 hours.
"This partnership between CALS
and the mechanical engineering
capstone program has been reward-
ing for all involved,” Scoggins said.
“Daniel has carefully communicated
the issues involved as well as facil-
itated construction. These talented
students have responded to the
challenges every step of the way.
We can't wait to fire this oast up at
harvest time."
Other open-source plans for oasts
exist, but according to Alexandra
Ringer, senior design team member,
the plans presented an opportunity
for improvement.
Jackson manages the hops re-
search yard at the Virginia Tech
Urban Horticulture Center. The