diff --git a/index.js b/index.js
index 7684d23..a8f0851 100644
--- a/index.js
+++ b/index.js
@@ -25,7 +25,7 @@ function hasBinary(data) {
   function _hasBinary(obj) {
     if (!obj) return false;
 
-    if ( (global.Buffer && global.Buffer.isBuffer(obj)) ||
+    if ( (global.Buffer && global.Buffer.isBuffer && global.Buffer.isBuffer(obj)) ||
          (global.ArrayBuffer && obj instanceof ArrayBuffer) ||
          (global.Blob && obj instanceof Blob) ||
          (global.File && obj instanceof File)