Manual commit inside a loop using Camel

Hello! I'm trying to do a manual commit a JMS transaction inside a loop using
camel:

from("direct:some-endpoint")
.routeId("my-route")
.process(createObject)
.marshal().json(JsonLibrary.Jackson)
.transacted("policyRequiresNew")
.loop(1000)
.to("jms:queue:my-queue")
.log("Sent!")
.end()
.end();

For instance, i want to commit each 50 registers sent to the queue, not
after all the registers are sent.
Does anyone know what can I do?

Thanks in advance.