Rubbing under hot water may be sufficient and then wash with a soap-based detergent. If the stain is very stubborn, it may be pre-treated with bile soap or lemon juice. Spray with stain remover before washing and add bleaching salt to the washing powder.
Apply lemon juice or alcohol from the pharmacist (80-90%) to the stain. The lemon juice or alcohol is best rubbed into the fabric with a cloth, cleaning away the dissolved substances with a paper towel (e.g. kitchen roll).
Treat the stain with lemon juice and salt. Then place in the sun. Leave for several hours to work and then wash out.