A beverage composition is disclosed that comprises a mixture of a protein hydrolysate and vitamin B2, and also contains an amount of ascorbic acid sufficient to prevent the generation of an off-flavor when the mixture is exposed to light. The off-flavor generated upon exposure to light can be reduced in accordance with the beverage composition of the present invention. Alss disclosed is a method for preventing an off-flavor in a beverage composition containing a protein hydrolysate and vitamin B2, and a process for producing a beverage composition containing a protein hydrolysate and vitamin B2. Furthermore, an agent for preventing an off-flavor in a beverage composition containing a protein hydrolysate and vitamin B2, wherein the agent comprises ascorbic acid as an active ingredient is disclosed.本發明係揭示一種飲料用組合物，其包含蛋白質水解物與維生素B2之混合物，該混合物含有足夠量之抗壞血酸，用以防止曝露於光下時產生異臭。藉由本發明之飲料組合物，可改善曝露於光下時產生之異臭。又，本發明提供一種含有蛋白質水解物與維生素B2之飲料用組合物之異臭防止方法，以及一種含有蛋白質水解物與維生素B2之飲料用組合物之製造方法。進而，本發明係揭示一種含有蛋白質水解物與維生素B2的飲料用組合物之異臭防止劑，其以抗壞血酸為主要成分。
