diff --git a/main/src/com/google/refine/importers/SeparatorBasedImporter.java b/main/src/com/google/refine/importers/SeparatorBasedImporter.java
index ad7f7afc1..7c2196bc8 100644
--- a/main/src/com/google/refine/importers/SeparatorBasedImporter.java
+++ b/main/src/com/google/refine/importers/SeparatorBasedImporter.java
@@ -76,7 +76,7 @@ public class SeparatorBasedImporter extends TabularImportingParserBase {
         
         JSONUtilities.safePut(options, "guessCellValueTypes", false);
         JSONUtilities.safePut(options, "processQuotes", true);
-        JSONUtilities.safePut(options, "quoteCharacter", CSVParser.DEFAULT_QUOTE_CHARACTER);
+        JSONUtilities.safePut(options, "quoteCharacter", String.valueOf(CSVParser.DEFAULT_QUOTE_CHARACTER));
 
         return options;
     }