diff --git a/spring-cloud-function-adapters/spring-cloud-function-adapter-gcp/src/main/java/org/springframework/cloud/function/adapter/gcp/FunctionInvoker.java b/spring-cloud-function-adapters/spring-cloud-function-adapter-gcp/src/main/java/org/springframework/cloud/function/adapter/gcp/FunctionInvoker.java
index bd0bc586d..ad25bc17e 100644
--- a/spring-cloud-function-adapters/spring-cloud-function-adapter-gcp/src/main/java/org/springframework/cloud/function/adapter/gcp/FunctionInvoker.java
+++ b/spring-cloud-function-adapters/spring-cloud-function-adapter-gcp/src/main/java/org/springframework/cloud/function/adapter/gcp/FunctionInvoker.java
@@ -30,6 +30,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
 import org.springframework.cloud.function.context.AbstractSpringFunctionAdapterInitializer;
+import org.springframework.cloud.function.context.config.ContextFunctionCatalogAutoConfiguration;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.support.MessageBuilder;
 import org.springframework.util.Assert;
@@ -68,8 +69,8 @@ public class FunctionInvoker extends AbstractSpringFunctionAdapterInitializer<Ht
 		}
 
 		// Default to GSON if implementation not specified.
-		if (!System.getenv().containsKey("spring.http.converters.preferred-json-mapper")) {
-			System.setProperty("spring.http.converters.preferred-json-mapper", "gson");
+		if (!System.getenv().containsKey(ContextFunctionCatalogAutoConfiguration.JSON_MAPPER_PROPERTY)) {
+			System.setProperty(ContextFunctionCatalogAutoConfiguration.JSON_MAPPER_PROPERTY, "gson");
 		}
 
 		Thread.currentThread() // TODO: remove after upgrading to 1.0.0-alpha-2-rc5
diff --git a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/config/ContextFunctionCatalogAutoConfiguration.java b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/config/ContextFunctionCatalogAutoConfiguration.java
index 8b3be3d1e..20527af40 100644
--- a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/config/ContextFunctionCatalogAutoConfiguration.java
+++ b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/config/ContextFunctionCatalogAutoConfiguration.java
@@ -79,7 +79,10 @@ public class ContextFunctionCatalogAutoConfiguration {
 	@Deprecated
 	static final String PREFERRED_MAPPER_PROPERTY = "spring.http.converters.preferred-json-mapper";
 
-	static final String JSON_MAPPER_PROPERTY = "spring.cloud.function.preferred-json-mapper";
+	/**
+	 * The name of the property to specify desired JSON mapper. Available values are `jackson' and 'gson'.
+	 */
+	public static final String JSON_MAPPER_PROPERTY = "spring.cloud.function.preferred-json-mapper";
 
 	@Bean
 	public FunctionRegistry functionCatalog(List<MessageConverter> messageConverters, JsonMapper jsonMapper,