When you make wine, you use the yeast *Saccharomyces cerevisiae* to ferment sugary juices. After you're done, you want to avoid them doing anything by using some chemicals etc. There are also other living things (especially bacteria) that can ruin your wine or food during storage. For example, there are bacteria that would turn your wine into vinegar. Have viruses been identified that infect and kill the bacteria that spoil wine or other foods?