Produce aisLe fermented flavor
One application is to serve the pears with seared foie gras
with eel sauce and trout roe. “The more the fermented pear is
chewed, a tingly carbonated sensation is experienced,” Yoon says.
“Flavor-wise, the fermented pear is sweet and savory from salt
brine with a hint of heat from fermented Korean chili peppers.”
She also freezes the used fermenting liquid for new kimchi
bases and sautes the peppers for sauces and marinades.
Yuzuki Japanese Eatery in San Francisco claims to be the
first restaurant in the U.S. to specialize in food prepared using
koji, an ingredient that has been used for centuries in Japan.
Koji is cooked rice and/or soybeans that have been inoculated
with a fermentation culture, Aspergillus oryzae, and used to
make soy sauce, miso, mirin and sake. It can be used to ferment
vegetables, too. When koji is combined with water and salt and
allowed to ferment, it turns into shio koji, or salt koji.
“This process of natural fermentation makes food more
palatable and easier to digest, with a mild flavor enhanced by naturally occurring amino
acids,” says chef/owner Yuko Hayashi.
Koji flourishes in a hot, humid environment, as befits a mold that evolved in the
Asian tropics. The spores first take root on moist, partially or fully cooked grains
within a week, releasing proteases, enzymes that breaks down proteins, and amylases
to break down starches as they grow, converting the grain into sugar and using that
sugar to fuel koji’s growth.
The resulting koji-grain culture is then mixed into a second product, for example,
cucumbers. The rice and cucumbers are stirred daily to aerate the rice and keep the
microbes in check. The proteases and amylases transform the cucumbers into a tart,
pungent food often imbued with funky overtones. “It makes the umami come out
nicely, so you don’t need too many ingredients to make it tastier,” Hayaski says.
Another favorite Japanese fermentation style is nukadoko, a rice bran pickling
bed created by mixing toasted rice bran, water and salt, then adding vegetable scraps
that ferment for 24 hours. The scraps are removed, the nukadoko is mixed to disperse
growing lactobacillus bacteria, new vegetable scraps are added for 24 hours, and it’s
hand-mixed daily for three days. This process continues for 14 days until the bacteria
have grown in number.
Once the nuka pickling bed is properly fermented, produce is buried in the
nukadoko for as long as needed—at least overnight for small vegetables and two to
four days for large ones. The pickled vegetables are now called nukazuke. Spices and
aromatics can be added to the pickling bed to ramp up the flavor—garlic and ginger to
add depth, dried seaweed to add umami, dried apple peels or dried persimmon peels to
add sweetness, and chili peppers to repel pantry bugs.
Jami Flatt, chef de cuisine at Departure, Portland, Oregon, typically ferments
radishes, cabbage, cucumbers, rutabaga and daikon in the nukadoko style. “The result
is a tart, acidic, salty, funky and crisp vegetables full of umami,” he says.
ROB BENES IS A CHICAGO-BASED HOSPITALIT Y INDUS TRY WRITER. CONTACT HIM A T ROBBENES@COMCAS T.NE T.
aBove, ToP: Jami Flatt at Departure ferments
radishes, cabbage, cucumber, rutabaga and daikon by
the nukadoko (rice bran pickling bed) method.
aBove, Bo TToM: Ji hyun yoon at Greenriver
ferments asian apple pears, Korean radishes, peppers,
carrots, green onion, garlic and ginger in a white
kimchi base liquid.