diff --git a/spring-web-reactive/src/main/java/org/springframework/core/io/buffer/support/DataBufferUtils.java b/spring-web-reactive/src/main/java/org/springframework/core/io/buffer/support/DataBufferUtils.java
index 5888ce8f34..745b42d42e 100644
--- a/spring-web-reactive/src/main/java/org/springframework/core/io/buffer/support/DataBufferUtils.java
+++ b/spring-web-reactive/src/main/java/org/springframework/core/io/buffer/support/DataBufferUtils.java
@@ -59,38 +59,42 @@ public abstract class DataBufferUtils {
 	}
 
 	/**
-	 * Returns the given data buffer publisher as an input stream, streaming over all
-	 * underlying buffers when available.
+	 * Returns the given data buffer publisher as a blocking input stream, streaming over
+	 * all underlying buffers when available.
 	 * @param publisher the publisher to create the input stream for
 	 * @return the input stream
 	 */
 	public static InputStream toInputStream(Publisher<DataBuffer> publisher) {
 		Iterable<InputStream> streams = Flux.from(publisher).
 				map(DataBuffer::asInputStream).
-				toIterable();
+				toIterable(1);
 
 		Enumeration<InputStream> enumeration =
-				new IteratorEnumeration<InputStream>(streams);
+				new IteratorEnumeration<InputStream>(streams.iterator());
 
 		return new SequenceInputStream(enumeration);
 	}
 
+	/**
+	 * Enumeration wrapping an Iterator.
+	 */
+	// TODO: move to CollectionUtils when we merge with Spring Framework?
 	private static class IteratorEnumeration<T> implements Enumeration<T> {
 
-		private final Iterator<T> delegate;
+		private final Iterator<T> iterator;
 
-		public IteratorEnumeration(Iterable<T> iterable) {
-			this.delegate = iterable.iterator();
+		public IteratorEnumeration(Iterator<T> iterator) {
+			this.iterator = iterator;
 		}
 
 		@Override
 		public boolean hasMoreElements() {
-			return delegate.hasNext();
+			return this.iterator.hasNext();
 		}
 
 		@Override
 		public T nextElement() {
-			return delegate.next();
+			return this.iterator.next();
 		}
 	}