Man's inherent salt appetite isn't the only reason we use salt in food. It helps make foods safe and appealing.

　　A rock you eat? Salt is an essential nutrient. Humans, indeed all animals, possess an inherent appetite for salt. Small wonder, then, that salt is the world’s oldest food additive. Salt brings to food far more than one of the five basic taste sensations （sweet, salty, sour, bitter and umami）; it enhances other tastes. Sweets taste sweeter. Salt masks bitter tastes, making naturally bitter foods like chocolate and broccoli become delicious.Before recorded history, men learned salt’s key role in food safety and preservation by retarding the growth of spoilage microorganisms. Today, food technologists rely on salt to satisfy consumer preferences in color, texture, appearance and aroma. And, all evidence suggests that consumers do have preferences, and they prefer the attributes that only salt can deliver.