diff --git a/validate_workflow.sh b/validate_workflow.sh
index 60e4f1461f5bf1fc20a43468fe6d265388b405fc..c7fb3f13d2c95459b534f80be07f387d871ca9bc 100755
--- a/validate_workflow.sh
+++ b/validate_workflow.sh
@@ -164,9 +164,7 @@ error() {
 
 get_mimetype() {
     local filename=$1
-    local res
-    res=$(file --mime-type "$filename" |  sed -e "s/^.*: //")
-    echo "$res"
+    echo "$( file --mime-type "$filename" |  sed -e "s/^.*: //" )"
 }