Soup soy sauce

Guk-ganjang () or soup soy sauce is a type of Korean soy sauce ("ganjang") made entirely of fermented soybeans ("meju") and brine. It is also a byproduct of "doenjang" production. Both lighter in colour and saltier than other Korean "ganjang" varieties, soup soy sauce is used mainly in "guk" (soup) and "namul" (a seasoned vegetable dish) in modern Korean cuisine.
Names.
Soup soy sauce is referred to by many different names. In the English-speaking world, it is most commonly known as "soup soy sauce", which is a direct translation of "guk-ganjang" (). The name "soup soy sauce" is used because it is used mainly for soup ("guk") in modern Korean cuisine. Also, it is the name used by many popular soy sauce brands such as Sempio, Daesang's Chung Jung One, and CJ Cheil Jedang's Beksul. Other names for the sauce include:
History.
The earliest soy sauce brewing in Korea seems to have begun prior to the era of the Three Kingdoms. The "Records of the Three Kingdoms", a Chinese historical text written and published in the 3rd century, mentions that "Goguryeo people are good at brewing fermented soy beans", in the section called "Dongyi" (Eastern foreigners), in the "Book of Wei". Jangdoks used for soy sauce brewing are found in the mural paintings of Anak Tomb No. 3 from 4th century Goguryeo.
In "Samguk Sagi", a historical record of the Three Kingdoms era, it is mentioned that "ganjang" and "doenjang" along with "meju" and "jeotgal" were prepared for the wedding ceremony of King Sinmun in February 683. "Sikhwaji", a section from "Goryeosa" (History of Goryeo), recorded that "ganjang" and "doenjang" were included in the relief supplies in 1018, after a Khitan invasion, and in 1052, when a famine occurred. Joseon texts such as "Guhwangchwaryo" and "Jeungbo sallim gyeongje" contain detailed procedures on how to brew good-quality "ganjang" and "doenjang." "Gyuhap chongseo" explains how to pick a date for brewing, what to forbear, and how to keep and preserve "ganjang" and "doenjang".
Production.
Soup soy sauce is made entirely of fermented soybeans and brine. The brewing process also produces "doenjang", a Korean fermented bean paste.
"Meju", Korean soybean brick, is made around "ipdong" in early November. Soybeans are soaked overnight, boiled in salt water, and then pounded in a mortar ("jeolgu") or coarsely ground with a millstone. About a "doe" (≈1.8 litres) or two of pounded soybeans are chunked, compressed, and shaped into a cube or a sphere called "meju". The meju bricks are then dried in a cool, shaded area for a week to several weeks until firm. When the bricks harden, they are tied with rice straws to the eaves of the house, or put in a warm ondol room with rice straw, to ferment. In Jeongwol, the first month of the lunar year, well-fermented "meju" bricks are washed and sun-dried.
After drying, the "meju" bricks are aged in "onggi" crocks ("jangdok") with brine. Charcoal and chillies are added for their adsorbent and antibacterial properties, as well as folk-religious beliefs that they drive away evil spirits. As the fermentation progresses, the brine acquires flavour and colour. This aged brine is boiled to become soy sauce, and the rest (aged "meju" chunks) is mashed to become soybean paste.
Types.
The Korean Ministry of Food and Drug Safety's "Food Code" classifies "hansik ganjang" into two categories by their ingredients:
Depending on the length of aging, "hansik ganjang" can be divided into three main varieties: clear, middle, and dark.