Used primarily in the industrial production of vitamin C (ascorbic acid) as a key intermediate in the Reichstein-Grüss process. It is enzymatically converted to 2-keto-L-gulonic acid, which is then chemically reduced to ascorbic acid. The calcium salt form enhances stability and solubility during processing, facilitating easier handling and purification in large-scale manufacturing. Its role is critical in achieving high yields of vitamin C, making it essential in pharmaceutical and food additive industries.