diff --git a/extensions/smallrye-reactive-messaging-kafka/deployment/src/main/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/DefaultSerdeDiscoveryState.java b/extensions/smallrye-reactive-messaging-kafka/deployment/src/main/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/DefaultSerdeDiscoveryState.java
index f4740fe592478..b6bade7d88c25 100644
--- a/extensions/smallrye-reactive-messaging-kafka/deployment/src/main/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/DefaultSerdeDiscoveryState.java
+++ b/extensions/smallrye-reactive-messaging-kafka/deployment/src/main/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/DefaultSerdeDiscoveryState.java
@@ -19,6 +19,7 @@ class DefaultSerdeDiscoveryState {
     private final IndexView index;
 
     private final Map<String, Boolean> isKafkaConnector = new HashMap<>();
+    private final Map<String, String> serdeConfigMap = new HashMap<>();
 
     private Boolean hasConfluent;
     private Boolean hasApicurio1;
@@ -40,6 +41,13 @@ boolean isKafkaConnector(boolean incoming, String channelName) {
         });
     }
 
+    void runIfConfigIsAbsent(String key, String value, Runnable runnable) {
+        if (value != null && !serdeConfigMap.containsKey(key)) {
+            serdeConfigMap.put(key, value);
+            runnable.run();
+        }
+    }
+
     boolean isAvroGenerated(DotName className) {
         ClassInfo clazz = index.getClassByName(className);
         return clazz != null && clazz.classAnnotation(DotNames.AVRO_GENERATED) != null;
diff --git a/extensions/smallrye-reactive-messaging-kafka/deployment/src/main/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/SmallRyeReactiveMessagingKafkaProcessor.java b/extensions/smallrye-reactive-messaging-kafka/deployment/src/main/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/SmallRyeReactiveMessagingKafkaProcessor.java
index 2687f5f4a0f05..3fbec6398fe20 100644
--- a/extensions/smallrye-reactive-messaging-kafka/deployment/src/main/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/SmallRyeReactiveMessagingKafkaProcessor.java
+++ b/extensions/smallrye-reactive-messaging-kafka/deployment/src/main/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/SmallRyeReactiveMessagingKafkaProcessor.java
@@ -65,14 +65,10 @@ void discoverDefaultSerdeConfig(DefaultSerdeDiscoveryState discovery,
             MethodInfo method = annotation.target().asMethod();
 
             processIncomingMethod(discovery, method, (keyDeserializer, valueDeserializer) -> {
-                if (keyDeserializer != null) {
-                    config.produce(new RunTimeConfigurationDefaultBuildItem(
-                            "mp.messaging.incoming." + channelName + ".key.deserializer", keyDeserializer));
-                }
-                if (valueDeserializer != null) {
-                    config.produce(new RunTimeConfigurationDefaultBuildItem(
-                            "mp.messaging.incoming." + channelName + ".value.deserializer", valueDeserializer));
-                }
+                produceRuntimeConfigurationDefaultBuildItem(discovery, config,
+                        "mp.messaging.incoming." + channelName + ".key.deserializer", keyDeserializer);
+                produceRuntimeConfigurationDefaultBuildItem(discovery, config,
+                        "mp.messaging.incoming." + channelName + ".value.deserializer", valueDeserializer);
             });
         }
 
@@ -85,14 +81,10 @@ void discoverDefaultSerdeConfig(DefaultSerdeDiscoveryState discovery,
             MethodInfo method = annotation.target().asMethod();
 
             processOutgoingMethod(discovery, method, (keySerializer, valueSerializer) -> {
-                if (keySerializer != null) {
-                    config.produce(new RunTimeConfigurationDefaultBuildItem(
-                            "mp.messaging.outgoing." + channelName + ".key.serializer", keySerializer));
-                }
-                if (valueSerializer != null) {
-                    config.produce(new RunTimeConfigurationDefaultBuildItem(
-                            "mp.messaging.outgoing." + channelName + ".value.serializer", valueSerializer));
-                }
+                produceRuntimeConfigurationDefaultBuildItem(discovery, config,
+                        "mp.messaging.outgoing." + channelName + ".key.serializer", keySerializer);
+                produceRuntimeConfigurationDefaultBuildItem(discovery, config,
+                        "mp.messaging.outgoing." + channelName + ".value.serializer", valueSerializer);
             });
         }
 
@@ -117,29 +109,27 @@ void discoverDefaultSerdeConfig(DefaultSerdeDiscoveryState discovery,
             }
 
             processIncomingChannelInjectionPoint(discovery, injectionPointType, (keyDeserializer, valueDeserializer) -> {
-                if (keyDeserializer != null) {
-                    config.produce(new RunTimeConfigurationDefaultBuildItem(
-                            "mp.messaging.incoming." + channelName + ".key.deserializer", keyDeserializer));
-                }
-                if (valueDeserializer != null) {
-                    config.produce(new RunTimeConfigurationDefaultBuildItem(
-                            "mp.messaging.incoming." + channelName + ".value.deserializer", valueDeserializer));
-                }
+                produceRuntimeConfigurationDefaultBuildItem(discovery, config,
+                        "mp.messaging.incoming." + channelName + ".key.deserializer", keyDeserializer);
+                produceRuntimeConfigurationDefaultBuildItem(discovery, config,
+                        "mp.messaging.incoming." + channelName + ".value.deserializer", valueDeserializer);
             });
 
             processOutgoingChannelInjectionPoint(discovery, injectionPointType, (keySerializer, valueSerializer) -> {
-                if (keySerializer != null) {
-                    config.produce(new RunTimeConfigurationDefaultBuildItem(
-                            "mp.messaging.outgoing." + channelName + ".key.serializer", keySerializer));
-                }
-                if (valueSerializer != null) {
-                    config.produce(new RunTimeConfigurationDefaultBuildItem(
-                            "mp.messaging.outgoing." + channelName + ".value.serializer", valueSerializer));
-                }
+                produceRuntimeConfigurationDefaultBuildItem(discovery, config,
+                        "mp.messaging.outgoing." + channelName + ".key.serializer", keySerializer);
+                produceRuntimeConfigurationDefaultBuildItem(discovery, config,
+                        "mp.messaging.outgoing." + channelName + ".value.serializer", valueSerializer);
             });
         }
     }
 
+    void produceRuntimeConfigurationDefaultBuildItem(DefaultSerdeDiscoveryState discovery,
+            BuildProducer<RunTimeConfigurationDefaultBuildItem> config, String key, String value) {
+        discovery.runIfConfigIsAbsent(key, value,
+                () -> config.produce(new RunTimeConfigurationDefaultBuildItem(key, value)));
+    }
+
     private void processIncomingMethod(DefaultSerdeDiscoveryState discovery, MethodInfo method,
             BiConsumer<String, String> deserializerAcceptor) {
         List<Type> parameterTypes = method.parameters();