As the gluten-free market grows and competition - from both specialists and interested conventional manufacturers - intensifies, innovation will be vital. The rate of product development is increasing - Mintel says one in ten products launched in the entire food sector last year was gluten free, up from 2% in 2005. However, as one industry watcher puts it, there is a lot of "spray and pray" to NPD in the category. What trends can manufacturers harness for success? Dean Best reports.