Fermented spicy cabbage known as kimchi It is a staple of Korean cuisine traditionally made in an earthenware vessel called OngiThese days, most Korean households have kimchi refrigerators for that purpose, but on a commercial scale, kimchi is made by mass fermentation in glass, steel, or plastic containers. made with these modern contraptions of the same quality as traditional fermentation methods? mania You would argue otherwise, and the Ongi now have the science to back up that claim.
It turns out that the porosity of the ongi walls helps the most desirable bacteria grow during the fermentation process. recent papers Published in the Journal of the Royal Society Interface. “I wanted to find a secret sauce that Ongi makes kimchi delicious.” Co-author David Hu said Georgia Institute of Technology. “So we measured how the gas evolved while the kimchi was fermenting in the jar, something no one had done before.”
Handcrafted clay vessels known as ongi have long been used by Korean chefs to ferment food. Ganjang (soy sauce), gochujang (chili paste), and Dunjan (miso), kimchi. Slice the cabbage or radish into small, uniform slices and sprinkle with salt as a preservative. Salt draws out moisture and inhibits the growth of many unwanted microorganisms. Then dry excess moisture and add seasonings, including sugar. This will further help bind any remaining free water in. Finally, place the salted cabbage in an airtight canning jar and let it sit at room temperature for the next 24-48 hours. The jars are sometimes “burped” to release the carbon dioxide formed during the fermentation process.
S. Kim and David Hu, 2023
However, there are many types of kimchi, and winter kimchi was traditionally made in large quantities to preserve the season and stored in the ground in large pots. i got you Kimchi fermented in Ongi for more than a month has significantly higher growth of desirable salt-loving lactobacilli than kimchi fermented in plastic or steel containers, producing undesirable lactic acid bacteria that can impart a foul odor to the final product. Delayed the growth of aerobic bacteria. Ongi becomes more sour, antioxidant effect According to Hu, kimchi others.
Wanting to learn more about the relationship between the material properties of ongi and the growth of bacteria during kimchi fermentation, Hu and his team turned to fluid dynamics for guidance. They purchased a large Ongi from a village on Jeju Island, South Korea, tall and wide enough to add an airborne carbon dioxide sensor. Ongi is traditionally made by pounding raw mud (made of water, silt, and clay) and picking up pebbles. The clay was then shaped into long bars and the final jar was shaped on a spinning wheel before drying.In the final step, he fired the ongi in a kiln for a day before cooling. The authors point out that this particular ongi is not glazed, which may hinder translucency.
Hu othersFirst, scanning electron microscopy and CT scanners were used to examine the pore structure of the imitation bark. We then tested the permeability of Ongi by observing how water evaporates from the container over time. Next, they experimented with the actual fermentation process by making their own kimchi.Three trials were done using purchased ongi and sealed glass jars. are equipped with carbon dioxide and pressure sensors, which is an important feature of fermentation, so changes in carbon dioxide were measured and compared.
