Engineering and Packaging IVV, in Germany.
“But texture, juiciness, and bite—this is
difficult.” To get a more fibrous, meat
like texture from plant-based protein,
Osen worked with other European Union
researchers to develop a way to stretch
globular plant proteins into strings and to
encourage them to cling together into fibres.
The project, called LikeMeat, targeted meat
alternatives that were satisfactory enough
to replace meat used in chicken nuggets, for
example, but might not be meaty enough to
replicate a fine steak.
The method uses a technique known as
high-moisture extrusion. Operators pour
water and powdered proteins, often soy or
yellow pea isolates, into a machine with two
long, intertwined screw like shafts extending
through controlled temperature zones. The
temperature control allows the mixture to
be heated as the screws mix and knead the
ingredients traveling down the chamber. The
plant proteins unfold, thanks to the heat, and
align in the direction of the flow as they move
through the screw. Then, at the end of the
extruder, a cooling die causes the mixture to
solidify and develop a fibrous texture. A final
step in the process shapes the mixture into
strips, crumbles, or other forms.
Details about how the processing parameters
and protein source impact the final product
texture are under wraps. But Osen and his
colleagues have experimented with boutique
proteins derived from locally grown crops like
peas, lentils, and lupin to produce vegetarian
burgers, schnitzel, and meaty pasta sauce.
Keshun Liu, a research chemist at the U.S.
Department of Agriculture’s Agricultural
Research Service, and Fu-Hung Hsieh, a
professor of bioengineering and food science
at the University of Missouri, have also worked
to develop this method, and their research
shows that disulfide bonds formed between
denatured soy proteins account for the fibrous
texture.
Both Osen and Hsieh are involved with
companies producing alternative meat
products using high-moisture extrusion. In
Germany, Osen says, there’s an interest in
eating less meat, yet there are fewer options
on grocery store shelves than in the U.S.
The California-based food producer Beyond
Meat licensed Hsieh’s high-moisture extrusion
process, and built a plant in Columbia, Mo.,
near the university. The company’s chicken
and ground beef are already available in some
stores. Food writer and cookbook author Mark
Bittman, in a column for the New York Times,
High-moisture extrusion of soy powder, wheat gluten, and starch creates strips with a
fibrous texture like meat, as in these imitation chicken strips. Image Credit: Keshun Liu.
AgriKultuur |AgriCulture
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