Changes in relative content of volatile compounds in cold brew coffee treated with IEF and HTST during storage. Note: Control-0, Control-14, and Control-28 represent untreated cold brew coffee stored for 0, 14, and 28 days, respectively. IEF-1-0, IEF-1-14, and IEF-1-28 represent cold brew coffee treated with IEF-1 stored for 0, 14, and 28 days, respectively. IEF-2-0, IEF-2-14, and IEF-2-28 represent cold brew coffee treated with IEF-2 stored for 0, 14, and 28 days, respectively. The redder the color, the higher the contents; the bluer the color, the lower the content. The contents in the table are all average values.