TLDR;
This video explores the traditional and modern methods of soy sauce production, highlighting the significant differences in time, ingredients, and flavor. It contrasts the 6-month fermentation process using koji mold with the 48-hour chemical hydrolysis method.
- Traditional soy sauce relies on a lengthy fermentation process using koji mold, soybeans, wheat, salt, and water.
- Modern, cheaper soy sauce uses hydrochloric acid to break down soybeans in a matter of hours, with additives to mimic the flavor of traditionally made soy sauce.
- Most people can't distinguish between the two in blind taste tests, which is why the faster, cheaper method dominates the market.
INTRO [0:00]
The video begins by introducing soy sauce as a common condiment, questioning whether the soy sauce at restaurants is real, considering that real soy sauce takes six months to make through the fermentation of soybeans and wheat in wooden barrels, unlike the 48-hour chemically produced versions. The video aims to explore the real soy sauce production process, what happens during the six months of fermentation, and why the fake stuff tastes similar.
HISTORY [1:04]
Soy sauce originated in China over 2,000 years ago as a method of preserving food using fermented fish and salt. In the 7th century, Buddhist monks began creating vegetarian versions using soybeans instead of fish. From China, soy sauce spread to Japan, Korea, and Southeast Asia, where it is known as showyu in Japan and ganjang in Korea. The basic process involves soybeans, wheat, salt, water, and time.
THE PROCESS [1:46]
The key ingredient in traditional soy sauce production is koji (Aspergillus oryzae), a mold also used in making sake and miso. Koji breaks down the proteins and starches in cooked soybeans and roasted wheat, creating enzymes that convert complex molecules into amino acids, sugars, and flavor compounds. The traditional process involves soaking soybeans overnight and steaming them until soft, roasting wheat until nutty, crushing it, and then mixing the soybeans and wheat while warm before adding koji spores. This mixture is spread in shallow trays and left in a warm, humid room for three days to allow the koji mold to grow. The koji is then mixed with salt water to create moromi, which is poured into wooden barrels and left to ferment for six months to three years. During fermentation, enzymatic breakdown and microbial fermentation occur simultaneously. Enzymes from the koji break down proteins into amino acids and starches into sugars, creating umami flavor, primarily from glutamic acid. Lactic acid bacteria and yeasts grow in the salty environment, producing more flavor compounds like esters, alcohols, and organic acids. The moromi transforms from thick and pastel-like to liquid and dark mahogany. After fermentation, the liquid is pressed out, filtered, and pasteurized to stop fermentation, resulting in raw soy sauce.
THE REVEAL [4:54]
The cheaper, faster method of producing soy sauce involves chemical hydrolysis. Soybeans are mixed with hydrochloric acid, which breaks down the proteins in hours instead of months. This process skips fermentation and koji. The result lacks the depth and complexity of traditionally fermented soy sauce. To compensate, producers add corn syrup for sweetness, caramel coloring to darken the mixture, and sometimes a small percentage of real fermented soy sauce to improve the taste. This type of soy sauce is called HVP (hydrolyzed vegetable protein) soy sauce.
VERSATILITY [6:34]
Most people cannot distinguish between real and HVP soy sauce in blind taste tests, especially when mixed with other ingredients. Real fermented soy sauce has a smoother, more complex flavor, but the difference is not always noticeable. HVP soy sauce dominates the market because it is cheaper and faster to produce. Real fermented soy sauce can cost up to five times more. To identify real soy sauce, check the ingredient list for soybeans, wheat, salt, and water. The presence of hydrolyzed soy protein or hydrolyzed vegetable protein indicates the chemical version. In Japan, premium bottles are labeled "hono," indicating traditional brewing with koji. Price is also an indicator, with real fermented soy sauce typically starting around $8 to $10 per bottle.
OUTRO [7:18]
The video concludes by revisiting the initial scenario of using soy sauce at a sushi restaurant. Viewers now understand the differences between traditionally fermented soy sauce and the cheaper, chemically produced version. They are encouraged to consider the process behind soy sauce production and to look for differences on the label when purchasing soy sauce.
