To prevent spoiling, many foods are treated with preservatives such as sulfur dioxide. When these foods are opened, the reaction with the air can create a smell of rotten eggs. This is not dangerous but unpleasant. But, it is not a sign of food gone bad. Sulfur can be removed differently depending on the product and its packaging. First, it is important to adapt storage conditions (cool, dry) to optimize the preservation of food products. When opening a vacuum-packed package. It is best to leave the wrapping intact by puncturing it and pouring the contents into another container. Do not open and close the bag too often as this causes more oxidation and thus deterioration of food taste and quality.