diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/CacheProperties.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/CacheProperties.java
index 6fe5a6d0b0..a0b87e3c1e 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/CacheProperties.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/CacheProperties.java
@@ -19,7 +19,6 @@ package org.springframework.boot.autoconfigure.cache;
 import java.time.Duration;
 import java.util.ArrayList;
 import java.util.List;
-import java.util.Optional;
 import java.util.concurrent.TimeUnit;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
@@ -245,16 +244,12 @@ public class CacheProperties {
 	/**
 	 * Redis-specific cache properties. Properties set will be used as the defaults for
 	 * all Redis caches.
-	 *
-	 * @see org.springframework.data.redis.cache.RedisCacheConfiguration
 	 */
 	public static class Redis {
 
 		/**
-		 * The TTL for entries. By default, entries do not expire, a value of zero
-		 * indicates an eternal entry, and the given value will be converted to seconds..
-		 *
-		 * @see Duration#parse(CharSequence)
+		 * Specifies the TTL (ultimately converted to seconds) for keys written to Redis.
+		 * By default, entries do not expire, and a value of {@link Duration#ZERO} disables the TTL.
 		 */
 		private Duration ttl = Duration.ZERO;
 
@@ -264,7 +259,8 @@ public class CacheProperties {
 		private boolean cacheNullValues = true;
 
 		/**
-		 * The non-null Redis key prefix to use instead of the default one.
+		 * Specifies an override for the default Redis key prefix. A value of {@literal null} results
+		 * in usage of the default key prefix.
 		 */
 		private String keyPrefix;
 
@@ -291,8 +287,8 @@ public class CacheProperties {
 			return this;
 		}
 
-		public Optional<String> getKeyPrefix() {
-			return Optional.ofNullable(this.keyPrefix);
+		public String getKeyPrefix() {
+			return this.keyPrefix;
 		}
 
 		public Redis setKeyPrefix(String keyPrefix) {
diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/RedisCacheConfiguration.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/RedisCacheConfiguration.java
index d8fa90b192..057a94313b 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/RedisCacheConfiguration.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/RedisCacheConfiguration.java
@@ -59,15 +59,12 @@ class RedisCacheConfiguration {
 
 	@Bean
 	public RedisCacheManager cacheManager(RedisConnectionFactory redisConnectionFactory) {
-
 		RedisCacheManagerBuilder builder = RedisCacheManager
 				.builder(redisConnectionFactory).cacheDefaults(getConfiguration());
-
 		List<String> cacheNames = this.cacheProperties.getCacheNames();
 		if (!cacheNames.isEmpty()) {
 			builder.initialCacheNames(new LinkedHashSet<>(cacheNames));
 		}
-
 		return this.customizerInvoker.customize(builder.build());
 	}
 
@@ -78,8 +75,8 @@ class RedisCacheConfiguration {
 		org.springframework.data.redis.cache.RedisCacheConfiguration config = org.springframework.data.redis.cache.RedisCacheConfiguration
 				.defaultCacheConfig().entryTtl(redisProperties.getTtl());
 
-		if (redisProperties.getKeyPrefix().isPresent()) {
-			config = config.prefixKeysWith(redisProperties.getKeyPrefix().get());
+		if (redisProperties.getKeyPrefix() != null) {
+			config = config.prefixKeysWith(redisProperties.getKeyPrefix());
 		}
 
 		if (!redisProperties.isCacheNullValues()) {