#CollectionOfRequests토론 중인 항목 0개

I have following code snippet:

<set-variable value="#[]" doc:name="Add Response"

doc:id="05bb1a62-3826-41dc-b4bb-8ef27e5b99cb"

variableName="responseArray" />

<foreach doc:name="For Each"

doc:id="1bf6620c-9156-4580-81e4-53f80d66d1da"

collection="#collectionOfRequests">

<wsc:consume operation="operation"

doc:name="Call Service" doc:id="6d44833e-9317-4dba-8011-7844d0e207dd"

config-ref="Web_Service_Consumer_Config" />

<set-variable value="#vars.responseArray &lt;&lt; (write(payload, 'application/xml'))" doc:name="Add Response" doc:id="a6516eff-a3c9-436c-85f5-79ce8be44608" variableName="addResponse" />  

</foreach>

The issue is, the response xml is not added to responseArray. I tried using dataweave but got the same issue.  

What is the right way to add a xml or json payload to an array so i can do an aggregation mapping?