美国采购需求：天然油、卡斯蒂利亚肥皂、护手霜、护肤品

I've been using your castile soap for quite some time, and I truly appreciate its quality and effectiveness. One aspect that piques my interest is the glycerin you incorporate in the product. Can you share what the source of this glycerin is? Understanding the origin of the ingredients is important for me as a customer who values transparency and quality in personal care products. Looking forward to your insights on this matter, as it helps me make informed purchasing decisions. Thanks!