diff --git a/spring-test/src/main/java/org/springframework/mock/web/MockCookie.java b/spring-test/src/main/java/org/springframework/mock/web/MockCookie.java
index fc9c7e784b26..3b06547f4ade 100644
--- a/spring-test/src/main/java/org/springframework/mock/web/MockCookie.java
+++ b/spring-test/src/main/java/org/springframework/mock/web/MockCookie.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -39,7 +39,7 @@
 @SuppressWarnings("removal")
 public class MockCookie extends Cookie {
 
-	private static final long serialVersionUID = 1198809317225300389L;
+	private static final long serialVersionUID = 4312531139502726325L;
 
 	private static final String SAME_SITE = "SameSite";
 	private static final String EXPIRES = "Expires";
@@ -47,6 +47,7 @@ public class MockCookie extends Cookie {
 	@Nullable
 	private ZonedDateTime expires;
 
+
 	/**
 	 * Construct a new {@link MockCookie} with the supplied name and value.
 	 * @param name the name
@@ -62,7 +63,7 @@ public MockCookie(String name, String value) {
 	 * @since 5.1.11
 	 */
 	public void setExpires(@Nullable ZonedDateTime expires) {
-		setAttribute(EXPIRES, expires != null ? expires.format(DateTimeFormatter.RFC_1123_DATE_TIME) : null);
+		setAttribute(EXPIRES, (expires != null ? expires.format(DateTimeFormatter.RFC_1123_DATE_TIME) : null));
 	}
 
 	/**
@@ -156,8 +157,8 @@ private static String extractAttributeValue(String attribute, String header) {
 
 	@Override
 	public void setAttribute(String name, @Nullable String value) {
-		if(EXPIRES.equalsIgnoreCase(name)) {
-			this.expires = value != null ? ZonedDateTime.parse(value, DateTimeFormatter.RFC_1123_DATE_TIME) : null;
+		if (EXPIRES.equalsIgnoreCase(name)) {
+			this.expires = (value != null ? ZonedDateTime.parse(value, DateTimeFormatter.RFC_1123_DATE_TIME) : null);
 		}
 		super.setAttribute(name, value);
 	}
@@ -175,8 +176,7 @@ public String toString() {
 				.append("HttpOnly", isHttpOnly())
 				.append(SAME_SITE, getSameSite())
 				.append("Max-Age", getMaxAge())
-				.append(EXPIRES, (this.expires != null ?
-						DateTimeFormatter.RFC_1123_DATE_TIME.format(this.expires) : null))
+				.append(EXPIRES, getAttribute(EXPIRES))
 				.toString();
 	}
 
diff --git a/spring-test/src/test/java/org/springframework/mock/web/MockCookieTests.java b/spring-test/src/test/java/org/springframework/mock/web/MockCookieTests.java
index 9783cb57cfec..6d284e3ea133 100644
--- a/spring-test/src/test/java/org/springframework/mock/web/MockCookieTests.java
+++ b/spring-test/src/test/java/org/springframework/mock/web/MockCookieTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -148,11 +148,11 @@ void setSameSiteShouldSetAttribute() {
 
 	@Test
 	void setExpiresShouldSetAttribute() {
+		String expiresText = "Tue, 8 Oct 2019 19:50:00 GMT";
 		MockCookie cookie = new MockCookie("SESSION", "123");
-		cookie.setExpires(ZonedDateTime.parse("Tue, 8 Oct 2019 19:50:00 GMT",
-				DateTimeFormatter.RFC_1123_DATE_TIME));
+		cookie.setExpires(ZonedDateTime.parse(expiresText, DateTimeFormatter.RFC_1123_DATE_TIME));
 
-		assertThat(cookie.getAttribute("expires")).isEqualTo("Tue, 8 Oct 2019 19:50:00 GMT");
+		assertThat(cookie.getAttribute("expires")).isEqualTo(expiresText);
 	}
 
 	@Test
@@ -168,11 +168,11 @@ void setSameSiteNullShouldClear() {
 
 	@Test
 	void setExpiresNullShouldClear() {
+		ZonedDateTime expiresDateTime = ZonedDateTime.parse("Tue, 8 Oct 2019 19:50:00 GMT",
+			DateTimeFormatter.RFC_1123_DATE_TIME);
 		MockCookie cookie = new MockCookie("SESSION", "123");
-		cookie.setExpires(ZonedDateTime.parse("Tue, 8 Oct 2019 19:50:00 GMT",
-				DateTimeFormatter.RFC_1123_DATE_TIME));
-		assertThat(cookie.getExpires()).isEqualTo(ZonedDateTime.parse("Tue, 8 Oct 2019 19:50:00 GMT",
-				DateTimeFormatter.RFC_1123_DATE_TIME));
+		cookie.setExpires(expiresDateTime);
+		assertThat(cookie.getExpires()).isEqualTo(expiresDateTime);
 
 		cookie.setExpires(null);
 		assertThat(cookie.getExpires()).isNull();
@@ -189,11 +189,12 @@ void setAttributeSameSiteShouldSetSameSite() {
 
 	@Test
 	void setAttributeExpiresShouldSetExpires() {
+		String expiresText = "Tue, 8 Oct 2019 19:50:00 GMT";
 		MockCookie cookie = new MockCookie("SESSION", "123");
-		cookie.setAttribute("expires", "Tue, 8 Oct 2019 19:50:00 GMT");
+		cookie.setAttribute("expires", expiresText);
 
-		assertThat(cookie.getExpires()).isEqualTo(ZonedDateTime.parse("Tue, 8 Oct 2019 19:50:00 GMT",
-				DateTimeFormatter.RFC_1123_DATE_TIME));
+		assertThat(cookie.getExpires()).isEqualTo(
+				ZonedDateTime.parse(expiresText, DateTimeFormatter.RFC_1123_DATE_TIME));
 	}
 
 	@Test
@@ -201,4 +202,5 @@ void setInvalidAttributeExpiresShouldThrow() {
 		MockCookie cookie = new MockCookie("SESSION", "123");
 		assertThatThrownBy(() -> cookie.setAttribute("expires", "12345")).isInstanceOf(DateTimeParseException.class);
 	}
+
 }