From Beijing to Tokyo, there's no accounting for different pastes
Although the flavour of fermented soya bean paste varies according to where it's made and is used differently in each country, all pastes are high in umami.
The 'fifth taste' combines the Japanese words of umai (delicious) and mi (taste). It was the name coined in 1907 by Japanese chemistry professor Kikunae Ikeda to name the flavour-enhancing qualities of kombu (giant sea kelp). The flavour enhancer (which he developed into monosodium glutamate) was derived from glutamate acid, a naturally occurring amino acid that can be found in many high-protein foods such as fish, shellfish, dairy products and some vegetables, as well as fermented and aged products including cheese, soy sauce and shrimp paste. Among them, fermented soya bean paste is one of the food products with a very high level of the meaty savouriness.
All fermented soya bean pastes start off the same. Soya beans are cooked, then mixed with other ingredients such as wheat, barley or rice before being left to ferment. Brine is added to the thick mass, which is left to ferment further. During fermentation, large amounts of free amino acids are released due to the high protein content of the soya beans, which, when combined with brine, results in a highly umami product. The liquid turns from clear to dark brown and is filtered from the bean paste solid mass and is then used as soy sauce.
The differences in taste, aroma, texture and colour - and hence, the different uses in cooking from country to country - lie in factors such as how long the paste is fermented, other ingredients added, the amount of salt used, and the temperature and humidity.
'Doenjang can be categorised by year,' says Tiffany Fung Mei-yan. 'The longer it is fermented, the darker the colour and the sweeter the taste, which makes it good for preparing meat or soup. A shorter fermentation means doenjang with lighter colour and taste, and makes it more suitable for making [lighter] soup.'
Other varieties of Korean soya bean paste include cheonggukjang, which has whole soya beans, and gochujang, in which chilli is added, giving it a spicy, pungent flavour, and which is commonly used in stews. Many commercial firms use alternative methods, including chemicals, to speed up fermentation, but Chau Wing-cheong of Tai Ma Sauce Company says the results aren't as good. 'There's no way mass-production and machines can create tasty min si zeong,' he says. 'It's all about the weather, the right timing and using high-quality ingredients such as soya beans from Canada and salt from Australia.
'Our min zi zeong stands [above others because of] the time it takes and the amount of sun, which is crucial for its dark brown colour and intense fragrance,' Chau says. 'It takes at least 13 months of sunlight and regular stirring to enhance the taste and consistency.'