diff --git a/src/main/java/org/gcube/datacatalogue/metadatadiscovery/bean/jaxb/MetadataField.java b/src/main/java/org/gcube/datacatalogue/metadatadiscovery/bean/jaxb/MetadataField.java
index 3e47033..0fc2c83 100644
--- a/src/main/java/org/gcube/datacatalogue/metadatadiscovery/bean/jaxb/MetadataField.java
+++ b/src/main/java/org/gcube/datacatalogue/metadatadiscovery/bean/jaxb/MetadataField.java
@@ -7,6 +7,7 @@ import java.io.Serializable;
 
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlAttribute;
 import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
@@ -30,6 +31,8 @@ public class MetadataField implements Serializable{
 	 */
 	private static final long serialVersionUID = 5935573474465015727L;
 
+	@XmlAttribute(name="categoryref")
+	private String categoryRef = null;
 	@XmlElement(required = true)
 	private String fieldName;
     @XmlElement(required = true)
@@ -72,6 +75,24 @@ public class MetadataField implements Serializable{
 	}
 
 
+
+	/**
+	 * @return the categoryRef
+	 */
+	public String getCategoryRef() {
+
+		return categoryRef;
+	}
+
+
+	/**
+	 * @param categoryRef the categoryRef to set
+	 */
+	public void setCategoryRef(String categoryRef) {
+
+		this.categoryRef = categoryRef;
+	}
+
 	/**
 	 * @return the fieldName
 	 */
@@ -240,7 +261,9 @@ public class MetadataField implements Serializable{
 	public String toString() {
 
 		StringBuilder builder = new StringBuilder();
-		builder.append("MetadataField [fieldName=");
+		builder.append("MetadataField [categoryRef=");
+		builder.append(categoryRef);
+		builder.append(", fieldName=");
 		builder.append(fieldName);
 		builder.append(", mandatory=");
 		builder.append(mandatory);
diff --git a/src/main/java/org/gcube/datacatalogue/metadatadiscovery/bean/jaxb/MetadataFormat.java b/src/main/java/org/gcube/datacatalogue/metadatadiscovery/bean/jaxb/MetadataFormat.java
index abe4bd3..a62d383 100644
--- a/src/main/java/org/gcube/datacatalogue/metadatadiscovery/bean/jaxb/MetadataFormat.java
+++ b/src/main/java/org/gcube/datacatalogue/metadatadiscovery/bean/jaxb/MetadataFormat.java
@@ -4,7 +4,6 @@
 package org.gcube.datacatalogue.metadatadiscovery.bean.jaxb;
 
 import java.io.Serializable;
-import java.util.ArrayList;
 import java.util.List;
 
 import javax.xml.bind.annotation.XmlAccessType;
@@ -35,6 +34,10 @@ public class MetadataFormat implements Serializable{
 	public MetadataFormat() {
 	}
 
+	@XmlElement(name = "metadatacategory")
+	private List<MetadataCategory> metadataCategories;
+
+
 	@XmlElement(name = "metadatafield")
 	private List<MetadataField> metadataFields;
 
@@ -50,9 +53,28 @@ public class MetadataFormat implements Serializable{
 	}
 
 
+
+	/**
+	 * @return the metadataCategories
+	 */
+	public List<MetadataCategory> getMetadataCategories() {
+
+		return metadataCategories;
+	}
+
+
+
+	/**
+	 * @param metadataCategories the metadataCategories to set
+	 */
+	public void setMetadataCategories(List<MetadataCategory> metadataCategories) {
+
+		this.metadataCategories = metadataCategories;
+	}
+
+
+
 	/**
-	 * Sets the metadata fields.
-	 *
 	 * @param metadataFields the metadataFields to set
 	 */
 	public void setMetadataFields(List<MetadataField> metadataFields) {
@@ -60,27 +82,6 @@ public class MetadataFormat implements Serializable{
 		this.metadataFields = metadataFields;
 	}
 
-	/**
-	 * Sets the metadatas.
-	 *
-	 * @param metadatas the metadatas to set
-	 */
-	public void setMetadatas(List<MetadataField> metadatas) {
-
-		this.metadataFields = metadatas;
-	}
-
-	/**
-	 * Adds the metadata.
-	 *
-	 * @param metadata the metadata
-	 */
-	public void addMetadata(MetadataField metadata){
-		if(this.metadataFields==null)
-			this.metadataFields = new ArrayList<MetadataField>();
-
-		this.metadataFields.add(metadata);
-	}
 
 
 	/* (non-Javadoc)
@@ -90,9 +91,12 @@ public class MetadataFormat implements Serializable{
 	public String toString() {
 
 		StringBuilder builder = new StringBuilder();
-		builder.append("MetadataFormat [metadataFields=");
+		builder.append("MetadataFormat [metadataCategories=");
+		builder.append(metadataCategories);
+		builder.append(", metadataFields=");
 		builder.append(metadataFields);
 		builder.append("]");
 		return builder.toString();
 	}
+
 }