Hello. I operate a small burger joint and wanted to introduce lemonade on the menu. I just wanted to know if the following method is correct for making lemonade: I prepare a concentrate of water, granulated sugar and lemon juice. I blend all three in a blender and then refrigerate the mix. This mix is then poured over a glass full of ice when the order comes. I just wanted to know if: 1. this method is fine for making lemonade. 2. how long will this concentrate stay good? Does lemon juice go bad over time? Can I keep the concentrate refrigerated for around two days. Additionally, If someone can recommend an alternate, better, more convenient method for making lemonade that will be appreciated. Thanks.