These are saponified (soap based) foaming concentrates. After many trials Vermont Soaps developed their own proprietary formula called Aloe Castile. They believe it to be the mildest castile soap formula available anywhere! This has become the base from which they developed their entire line of castile liquid soaps, bath & shower gels and nontoxic cleaners. The word castile is a reference to La Castilla - a region in central Spain historically significant in the history of soapmaking. In America, castile means any soap made with olive oil, often a liquid soap made from coconut and olive. Check your ingredients - some companies add synthetic foaming boosters! 32oz