Some seeds like soap nuts have very hard shell? why?
Answers
The natural soap found in these berries is called saponin. Saponin is a natural cleaner that works as a surfactant, breaking the surface tension of the water to penetrate the fibers of your clothing, lifting stains from the fabric, and leaving dirt suspended in the water that is rinsed away.
Eco Nuts Soap Nuts are gentle on both clothes and skin, making them ideal for those with sensitive skin, eczema, allergies and psoriasis. Because they are so mild, they are perfect for baby clothes and even cloth diapers. All-Natural Eco Nuts Soap Nuts are also great for septic and grey water systems. Unlike commercial soaps, that have artificial foaming agents, soap nuts do not produce lots of bubbles or foam. While commercial detergents and soaps have marketed heavily around that visual, foam simply is not an indicator of cleaning power.
All Soap Nuts by Eco Nuts are wild-harvested, meaning they are gathered from wild trees grown without any kind of chemicals, fertilizers, or pesticides. Saponin actually tastes bad to insects so no pesticides are needed, and the trees naturally love poor uncultivated soil. They are organically grown by mother earth and certified USDA Organic by Oregon Tilth.