diff --git a/app/code/core/Mage/CatalogSearch/Model/Indexer/Fulltext.php b/app/code/core/Mage/CatalogSearch/Model/Indexer/Fulltext.php
index 584cd7c50ed..7ca76d80674 100644
--- a/app/code/core/Mage/CatalogSearch/Model/Indexer/Fulltext.php
+++ b/app/code/core/Mage/CatalogSearch/Model/Indexer/Fulltext.php
@@ -335,6 +335,7 @@ protected function _getSearchableAttributes()
             $attributeCollection = Mage::getResourceModel('catalog/product_attribute_collection');
             $attributeCollection->addIsSearchableFilter();
 
+            $this->_searchableAttributes = [];
             foreach ($attributeCollection as $attribute) {
                 $this->_searchableAttributes[] = $attribute->getAttributeCode();
             }