Demi (Half) Fraser is a modification of Fraser Broth base. This media was developed by Fraser and Sperber for the rapid detection of Listeria from food and environmental samples. The addition of ferric ammonium citrate allows for the improved recovery of Listeria spp. With the EZ-Media Dry Bag format, the entire medium preparation method takes less than 30 minutes. Just add deionized water through the “in” port and gently massage the bag to mix. For the 5L bags, there are 15 dry media bags per case. For the 20L bags, there are 12 bags per case. All Actero™ Universal Enrichment Media are standard, high quality formulations and ISO compliant.