diff --git a/myconext-server/src/main/java/myconext/aa/AttributeAggregatorController.java b/myconext-server/src/main/java/myconext/aa/AttributeAggregatorController.java
index 433c2a6b..f79896e3 100644
--- a/myconext-server/src/main/java/myconext/aa/AttributeAggregatorController.java
+++ b/myconext-server/src/main/java/myconext/aa/AttributeAggregatorController.java
@@ -49,7 +49,7 @@ public ResponseEntity<List<UserAttribute>> aggregate(@RequestParam("sp_entity_id
             userAttributes.add(new UserAttribute("urn:mace:eduid.nl:1.1", eduID));
         });
 
-        LOG.debug(String.format("Attribute aggregation response %s", userAttributes));
+        LOG.debug(String.format("Attribute aggregation response %s", userAttributes.stream().map(Object::toString).collect(Collectors.joining(", "))));
 
         return ResponseEntity.ok(userAttributes);
     }