Background
History
Recent achievement
2. Manufacturing process (Bioprocess)
Upstream
Midstream
Downstream
3. Conclusion
4. References
The fermentation method takes up to six months to complete and results in a transparent, delicately colored broth with balanced flavor and aroma.
The non-brewed sauces take only two days to make and are often opaque with a harsh flavor and chemical aroma.
Quality Control
Numerous analytical tests are conducted to ensure the finished sauce meets minimum quality requirements. For example, in brewed sauces, there are several recommended specifications. Total salt should be 13-16% of the final product; the pH level should be 4.6-5.2; and the total sugar content should be 6%. For the non-brewed type, there is 42% minimum of hydrolyzed protein; corn syrup should be less than 10%; and carmel color 1-3%.
In the United States, the quality of the finished sauce is protected under federal specification EE-S-610G (established in 1978) which requires that fermented sauce must be made from fermented mash, salt brine, and preservatives (either sodium benzoate or benzoic acid). This specification also states that the final product should be a clear, reddish brown liquid which is essentially free from sediment. The non-fermented sauce is defined as a formulated product consisting of hydrolyzed vegetable protein, corn syrup, salt, caramel color, water, and a preservative. It should be a dark brown, clear liquid.
The Japanese, on the other hand, are more specific in grading the quality of their soy sauces. They have five types of soy sauce: koikuchi-shoyu (regular soy sauce), usukuchi-shoyu (light colored soy sauce), tamari-shoyu, saishikomi-shoyu, and shiro-shoyu. These types are classified into three grades, Special, Upper, and Standard, depending upon sensory characteristics such as taste, odor, and feel in the mouth, as well as analytical values for nitrogen content, alcohol level, and soluble solids.
Industrial production of soy sauce, B.S. Luh, Dept of Food Science & Technology, University of California, Davis, CA 95616, USA
Wood, Brian J. B., ed (1998). Microbiology of fermented foods, Blackie academic & professional
Hutkins, Robert Wayne (2006), Microbiology and technology of fermented foods, Blackwell publishing

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