Tamari and shoyu sauce by Bertyn is a traditional, artisan soy sauce.

We distinguish three qualities of soy sauce. Bertyn uses the highest quality for its bio seitan: a traditionally brewed soy sauce prepared with craftsmanship. The second quality is naturally brewed soy sauce and the third is the totally inferior non-brewed soy sauce which is often found in supermarkets at a very low price.

For its spelt and Manitoba seitan, Bertyn uses the traditionally brewed artisanal organic soy sauce.
Bertyn uses two varieties for its soy sauce: shoyu (soy sauce with rye) and tamari (soy sauce without rye).
The tamari used by Bertyn is a rare rye-free soy sauce brewed according to a 500 year old recipe. Yoshio Aoki, the current 4^th generation tamari brewer, takes pride in his traditional recipe and the techniques of his ancestors: fully organic ingredients, hand-made soy bean koji, a high proportion of soy beans vs. water and a long maturing process in cedar casks.

The shoyu sauce is prepared following an ancient Japanese recipe. Whole soy beans are cooked and mixed with broken rye. The mixture is then enriched with Koji, a culture of fungi mould spores of the Aspergillus Oryzae. This process takes three days, after which the mixture is set to ripen in cedar casks or ‘kegs’ at surroundings’ temperature during 15 months. The sap is manually pressed from the cloths that contain the brew. (dixit Serge)

This process does not involve chemistry or chemicals; nature can have its course. Less than 1% of all soy sauce manufactured in Japan today, is produced in this artisanal way.

The long ripening process – via fermentation - in wooden casks creates the natural protein “glutamic acid”, ensuring a rich and delicious aroma. A complex of sweet and umami (typical of glutamic acid) is the end result of this traditionally brewed, artisanal soy sauce, highly appreciated by connoisseurs.

umami, savory, savoury, umami means ‘good flavour, good smell’

Umami: during an investigation into the strong flavour and smell of seaweed bouillon in 1908, Kikunae Ikeda discovered the umami flavour. He was the inventor of the flavour imitator and enhancer ‘monosodium glutamate’ (MSG), developed via a chemical process and later patented. In a chemical form it is often used in yeast extracts, soy extracts, protein isolates, hydrolysed vegetable proteins, hydrolysed yeast and autolysed yeast. This chemically produced flavour enhancer creates negative side effects such as headaches, migraine and asthma, which do not occur from the natural product.

Naturally brewed soy sauce.
Most soy sauces are no longer brewed the traditional way. There are two key differences between soy sauce from large enterprises in Japan, the EU and the U.S., and the superior traditionally brewed artisanal soy sauce.

1. The first apply a faster fermentation process by using degreased soy proteins instead of entire soy beans. This degreased soy flour is the residue (the press cake) of the soybean oil industry, whereby the soybean oil is obtained from the soy beans by use of the volatile yet toxic hexane. What remains is a degreased flour that may contain traces of hexane.

2. Automated koji production is sped up by applying high temperatures in plastic or metal tanks and will take only 3 to 6 months.

The majority of higher quality Japanese brands follow this method.

The result misses the finishing touch in flavour and smell and is less easily digestible. However, it is still much better than non-brewed sauce.

Non-brewed supermarket soy sauce is the price champion.

This soy sauce rather tastes of meat and is available in a darker or lighter version.

Both are at a huge distance from healthy and real soy sauce. In their production process, degreased soy flour is mixed with hydrochloric acid at high temperatures and under pressure in order to obtain hydrolysed vegetable proteins. Salt, caramel and chemical preservatives and flavourings are then added. Glutamate enzymes are used as a catalyst in order to produce high quantities of the unnatural form of glutamate found in MSG. This non-brewed cheap soy sauce often contains high concentrations of the toxic chemicals 3-MCPD, furanones and chlorophenols.

Mirin, sweet sake used in Bertyn bio seitan soy sauce. Around 1500 (the Muromachi period), mirin was used as a type of enriched wine; it would become sour very quickly as a result of the yeast in the liquid.
Using shochu, traditionally distilled liquor, as a base for mirin eliminated the problem: the flavour lasted and the mirin no longer turned sour. This is how mirin could become a common product in the traditional Japanese cuisine during the Edo period (1603-1868), and it also became a fixed part of the Kyoto multiple course meal 'kaiseki ryori'.

The mirin used in Bertyn soy sauce ripens for 12 months; its quality is based on the koji culture and the brewing process. The koji enhances the flavour of the gluey, sweet rice. Rice is washed, rinsed, steamed and cooled to exact temperatures. Next, koji is added to the rice and the shochu. This ‘mirin moromi’ mixture is then pumped into enamel casks for fermentation. After three months of fermentation and regular stirring, the mirin is poured into bags and wrung out. The mirin then matures for 150-200 more days before the sediment is removed.

The result is a sweet, amber coloured dressing which adds a delicate flavour to even the simplest recipe.

extraordinary flavour

Onderkant formulier

Mirin moromi in enamel barrel

Onderkant formulier

Yoshio Aoki and his son.
tamari quality control.