Since 1941. Genuine brewed. Diluted with water to 4.5% acidity. Acidity: Above 4.5%. There is no substitute for the rich aroma and flavor of glutinous rice fermentation that Kong Yen rice vinegar be made from top grade glutinous rice with a state-of-the-art fermentor which eliminate any chance of contamination and utilize the best yeast and koji culture for the best rice vinegar. ISO 22000. HACCP. http://www.kongyen.com.tw. Product of Taiwan.