Sour plum soup plum preparation materials: 3 kg salt: 4 liang white vinegar: 1 kg recipe features: stewed duck and steamed ribs with sour plum soup are really delicious! Pure taste, without adding any bad chemicals. Production step (4) 1. Cooking plum roast duck and steamed pork ribs with sour plum is really delicious! Pure taste, without adding any bad chemicals. 2. Put the dried plums into a jar washed and dried in advance, and sprinkle a handful of salt evenly on each layer of plums. 3. Put all the plums and salt in the jar, pour the white vinegar and cover it. 4. Put the jar in the shade and marinate for 1 year.