Fermented Soy Sauce HEMF Reduction via Water Ratio Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional brewed soy sauce production methods struggle to reduce the characteristic soy sauce smell (HEMF) while maintaining the desirable yeast-derived flavor components like methionol, resulting in soy sauces with either strong soy sauce smells or compromised quality.
Innovation Solution
Increasing the water ratio of the aqueous common salt solution to 170-450% during fermentation and adding additional koji or moromi to the first stage moromi, allowing for further fermentation and maturation, which reduces HEMF to 15.0 ppm or less and maintains methionol at 2.0 ppm or more per 1.0% (W/V) of total nitrogen.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If conventional brewing methods are used to produce soy sauce, then the characteristic soy sauce smell (HEMF) is enhanced, but the soy sauce smell becomes too strong for modern consumer preferences
Solution Approach 1:
The patent changes the water-to-koji ratio parameter from conventional values to 2.0-4.0 times the volume of koji, and controls fermentation temperature at 20-30°C for 1-7 days. These parameter changes suppress HEMF generation while maintaining other flavor components, resolving the contradiction between characteristic smell and consumer acceptance.
Solution Approach 2:
The patent performs preliminary fermentation of koji before mixing with salt and water to create moromi. This preliminary action allows control over enzyme activation and starch conversion before the main fermentation, enabling better control of HEMF formation while preserving desirable flavors.
2Object-affected harmful factors
If yeast fermentation is suppressed to reduce HEMF generation, then soy sauce smell is reduced, but yeast-derived flavor components like methionol are also lost
Solution Approach 1:
The patent applies partial fermentation by controlling the fermentation time (1-7 days) and temperature (20-30°C) to achieve only partial development of HEMF while maintaining sufficient yeast activity for methionol production. This partial action resolves the contradiction by stopping fermentation at an optimal point before excessive HEMF accumulates.
Solution Approach 2:
The patent optimizes the water-to-koji ratio to 2.0-4.0 times volume, which creates a specific fermentation environment that favors methionol production while limiting HEMF generation. This parameter change enables selective accumulation of desired flavor components.
3Object-affected harmful factors
If high temperature digestion is used to suppress yeast fermentation, then HEMF accumulation is avoided, but the soy sauce loses matured umami taste and yeast-derived delicate taste
Solution Approach 1:
The patent uses periodic fermentation at moderate temperatures (20-30°C) over 1-7 days instead of continuous high-temperature digestion. This periodic, controlled fermentation allows gradual development of umami and delicate yeast flavors while preventing excessive HEMF accumulation, maintaining flavor quality.
Solution Approach 2:
The patent replaces the mechanical/thermal approach (high-temperature digestion) with a biochemical approach (controlled enzymatic fermentation at moderate temperatures). This substitution preserves heat-sensitive flavor compounds while still controlling HEMF formation through biochemical pathways.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This process produces a soy sauce with a reduced soy sauce smell, excellent masking abilities for unpleasant flavors, a rich flavor profile, and a very light color, while maintaining the umami taste and yeast-derived delicate taste, suitable for use as a condiment.
Implementation Method 1
inoculation and culturing of a koji mold therein to make a soy sauce koji, addition (mixing) of an aqueous common salt solution thereto to make a soy sauce moromi, fermentation and maturation
Implementation Method 2
fermentation and maturation, press-filtration to make a clear liquid, and pasteurisation (sterilzation under heating)... HEMF serving as a high boiling component of soy sauce is efficiently removed by decompression, absorption, or the like... HEMF is generated and accumulated by soy sauce yeast fermentation
Implementation Method 3
heat denaturation of either soybeans alone or a combination of soybeans and grains such as cereals
Implementation Method 4
press-filtration to make a clear liquid
Implementation Method 5
pasteurisation (sterilzation under heating)
Data Source
AI summary
It is intended to provide a means for obtaining a novel soy sauce with less soy sauce smell and having a rich flavor although it is a brewed soy sauce. More particularly, it is intended to provide a process for producing such a brewed soy sauce, comprising: preparing a soy sauce koji; preparing a soy sauce moromi by adding an aqueous common salt solution to the soy sauce koji at a ratio of water within 170% to 450% (V/V); fermenting and maturating the soy sauce moromi; adding either a soy sauce koji alone or a combination of a soy sauce koji and an aqueous common salt solution to the soy sauce moromi during the fermentation and maturation; and further fermenting and maturating the soy sauce moromi after the addition thereof.