diff --git a/lib/util-iso-mount.sh b/lib/util-iso-mount.sh
index 6059cdf..9685565 100644
--- a/lib/util-iso-mount.sh
+++ b/lib/util-iso-mount.sh
@@ -80,7 +80,8 @@ umount_fs(){
         unset FS_ACTIVE_MOUNTS
         rm -rf "${mnt_dir}/work"
     fi
-    for i in "$(grep ${work_dir} /proc/mounts | awk '{print$2}' | sort -r)"
+    mount_folders=$(grep "${work_dir}" /proc/mounts | awk '{print$2}' | sort -r)
+    for i in mount_folders
     do
         cat /proc/mounts
         info "umount: [%s]" "$i"