Plastic, Glass, or Tin: Which is Best? Maple syrup is packed in a variety of retail containers. Glass allows the color and clarity of maple syrup to clearly show. A wide range of designs available. Best for maintaining flavor of syrup. Plastic best for shipping. Maintains the flavor of syrup, although color may darken somewhat in storage. Tin traditional packaging appeals to many customers. Maintains color well. Regardless of the packaging, once opened, maple syrup should be refrigerated or frozen to maintain quality and flavor of the product.