diff --git a/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/export/prometheus/PrometheusScrapeEndpoint.java b/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/export/prometheus/PrometheusScrapeEndpoint.java
index eb179c543842..be0aec1cf441 100644
--- a/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/export/prometheus/PrometheusScrapeEndpoint.java
+++ b/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/export/prometheus/PrometheusScrapeEndpoint.java
@@ -56,7 +56,7 @@ public WebEndpointResponse<String> scrape(TextOutputFormat format, @Nullable Set
 					? this.collectorRegistry.filteredMetricFamilySamples(includedNames)
 					: this.collectorRegistry.metricFamilySamples();
 			format.write(writer, samples);
-			return new WebEndpointResponse<>(writer.toString(), format);
+			return new WebEndpointResponse<>(writer.toString(), format.getContentType());
 		}
 		catch (IOException ex) {
 			// This actually never happens since StringWriter doesn't throw an IOException
diff --git a/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/export/prometheus/TextOutputFormat.java b/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/export/prometheus/TextOutputFormat.java
index 4831d37cf3f0..858066d0fd99 100644
--- a/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/export/prometheus/TextOutputFormat.java
+++ b/spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/export/prometheus/TextOutputFormat.java
@@ -24,6 +24,7 @@
 import io.prometheus.client.exporter.common.TextFormat;
 
 import org.springframework.boot.actuate.endpoint.Producible;
+import org.springframework.http.MediaType;
 import org.springframework.util.MimeType;
 import org.springframework.util.MimeTypeUtils;
 
@@ -38,7 +39,7 @@ public enum TextOutputFormat implements Producible<TextOutputFormat> {
 	/**
 	 * OpenMetrics text version 1.0.0.
 	 */
-	CONTENT_TYPE_OPENMETRICS_100(TextFormat.CONTENT_TYPE_OPENMETRICS_100) {
+	CONTENT_TYPE_OPENMETRICS_100("application/openmetrics-text") {
 
 		@Override
 		void write(Writer writer, Enumeration<MetricFamilySamples> samples) throws IOException {
@@ -50,7 +51,7 @@ void write(Writer writer, Enumeration<MetricFamilySamples> samples) throws IOExc
 	/**
 	 * Prometheus text version 0.0.4.
 	 */
-	CONTENT_TYPE_004(TextFormat.CONTENT_TYPE_004) {
+	CONTENT_TYPE_004(MediaType.TEXT_PLAIN_VALUE) {
 
 		@Override
 		void write(Writer writer, Enumeration<MetricFamilySamples> samples) throws IOException {
@@ -61,8 +62,11 @@ void write(Writer writer, Enumeration<MetricFamilySamples> samples) throws IOExc
 
 	private final MimeType mimeType;
 
+	private final MimeType contentType;
+
 	TextOutputFormat(String mimeType) {
 		this.mimeType = MimeTypeUtils.parseMimeType(mimeType);
+		this.contentType = MimeTypeUtils.parseMimeType(TextFormat.chooseContentType(mimeType));
 	}
 
 	@Override
@@ -70,6 +74,10 @@ public MimeType getProducedMimeType() {
 		return this.mimeType;
 	}
 
+	MimeType getContentType() {
+		return this.contentType;
+	}
+
 	abstract void write(Writer writer, Enumeration<MetricFamilySamples> samples) throws IOException;
 
 }