Egg Yolk Enrichment (50% ) BD Difco™ 6 x 100 ml. Is a concentrated egg yolk emulsion recommended for use in a variety of media such as BD Difco™ SFP Agar Base and BD Difco™ McClung Toabe Agar Base for the isolation andidentification of Clostridium species on the basis of their lecithinase activity. Egg Yolk Enrichmentwhich has been warmed to 45 - 50°C is aseptically added to prepared and sterilizedculture media which has been cooled to 45 - 50°C. In BD Difco™ SFP Agar Base and Difco™ McClung Toabe Agar Base, 100 ml Egg Yolk Enrichment 50% is added to 900 ml or 10 ml to 90 ml of prepared and sterilized base. Use with: McClung Toabe Agar Base (Cat. No. 294110), MYP Agar (Cat. No. 281010) and SFP Agar Base (Cat. No. 281110).