Editing Nutrient Broth (section)

== E Broth  ==

Eddleman Broth is simpler for your home micro lab and many bacteria will grow very well on it, but the scum, sediment, and other results of bacterial growth will differ somewhat from the results on classic broth. Some bacteria grow better if you omit the salt. Salt (5 grams per liter) is used added if we are growing bacteria from human gut or decaying meat, but the bacteria usually grow fine without the salt. We will omit peptone because you don't have it. Use ground beef, or ground liver, or any kind of meat you wish. 

Mix 1/2 pound of fresh ground meat with 1 liter of tapwater and let stand several hours in the refrigerator, stir occasionaly to aid extraction of soluble proteins. Heat to boiling, with stirring, until the meat is cooked to coagulate proteins. Filter through a white cloth which is thick enough to remove all particles. Discard the meat. If you worked cleanly (clean pans and clean cloth) and used refrigerator temperature for the extraction, the discarded meat is safe for human food. Chill the broth in refrigerator so that the fat forms a hard floating layer. Discard the fat. Adjust the volume to one liter by adding tapwater. Do not adjust pH because you do not have a pH meter or pH paper and most bacteria will grow fine. If you wish add a 1/8 inch crushed limestone pebble to some of the culture tubes to see if there is any difference in growth of bacteria, or use powdered limestone or calcium carbonate. Dispense into tubes, plug with cotton, and autoclave in pressure cooker at 15 pounds pressure for 15 minutes. Let tubes cool in pressure cooker. 

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