对这些物质不是很了解。网上查到：
While both "sulfur" and "sulfites" involve the element sulfur, they are not the same. Sulfur is a natural element, while sulfites are a class of sulfur-based compounds, including preservatives, used to prevent spoilage and extend shelf life, particularly in food and beverages.
有机食物里用盐、糖作为保鲜机制，总是感到相对比较自然。
