Look at the composition. If the glutamate sodium or E621 is added besides the spices - an additive, an amplifier of taste, - then such spices are very dangerous to health. The E621 can cause gastritis, stomach ulcers, and another Chinese restaurant syndrome, which is accompanied by headaches, rapid heartbeat, weakness in muscles and heat in the chest. Allergic may arise. Therefore, be sure to look at the composition and buy spices without glutamate.
Buy spices separately. All more often in stores sell spices sets: for fish, for beef, for povet and so on. It is better to abandon such mixes, because unscrupulous manufacturers can add low-quality and overdue spices to them. In the mixture, they are very easy to hide. It is better to purchase components individually and stirred at home.
Buy whole spices. If possible, buy integers, not ground spices. For example, peas pepper, not ground. Pokrov and husk help preserve the fragrance longer. As soon as the spices are twisted, their fragrance will begin to be exhausted, and they will ruin in a few months. And spices can be grinding at home.
Check the packaging. It does not matter, in which packaging is stored in spices: in a glass or plastic bottle, in a paper or polyethylene package. The main thing is that the packaging is hermetic. Otherwise, essential oils will be destroyed from the spices, and they will lose their fragrance. Check it before buying, as in the store it could damage it at the time of unloading.
Check the shelf life. The shelf life of any spices is six months. After that, the spices cease to be useful and give the right taste dishes.