It is important to realize that we are prohibited from the Torah (Vayikra XI) to eat Sheratzim. This issue includes many types of insects. Therefore, a bowl of salad which may look kosher, could have more non-kosher ingredients (bugs) and prohibitions than a cheeseburger at a local fast food restaurant. Although Reb Moshe Feinstein zt"l states that it is not mandatory at this time to check vegetables for bugs, he was refering to a time when DDT (a strong pesticide) was widely used on most crops. This pesticide, when used, served to temporarily eliminate the vast majority of insects from vegetables, herbs and teas . Unfortunately, due to various agricultural modifications, the insects are back! In the United States, the insecticide DDT is now officially and legally outlawed. Now, often over half a dozen species can be found on one head of lettuce.

Usually, something as small as an insect would be "batel" (anulled) in a large volume of permissible food. In the case of insects, however, this is not the case. The reason is that we have a rule which states that a complete creature cannot become nullified. Therefore, a worm on the bottom of a tequilla bottle does not become nullified by the liquid. However, if a person cooked soup and found a fly floating in it later, the fly should be removed and the soup will now be permissible. If there were three or more insects in the food, we have to assume that it was infested with insects and must be sifted, strained etc. If there are only parts of insects, they are considered nullified in sixty. However, whenever possible, a person must try to remove the insect parts as well. This is the reason why in Israel many people who have found insecdt parts in their flour always sift it.

All fresh fruits and vegetables are kosher in principle. Jewish law requires that they be carefully checked and cleaned to make sure that there are no insects on them, as insects are not kosher. The Orthodox community is particular not to consume produce which may have insect infestation, and check and wash certain forms of produce very carefully. Many Orthodox Jews avoid certain vegetables, such as broccoli, because they may be infested and exceedingly hard to clean. Some kashrut certifying organizations completely recommend against consumption of certain vegetables they deem impossible to clean.

According to the U.S. Dept. of Agriculture, commercially it is not possible to remove all insects, and a sizable amount remain.

A common problem with vegetables involves possible insect infestation. The prohibition against consuming insects, even very tiny ones -- as long as they are visible to the naked eye -- is mentioned five times in the Torah and is very strict. In recent years, due to federal regulations restricting insecticide spraying and genetic changes causing some insects to become more resistant to the insecticides, there are increasing amounts of insects such as thrips and aphids infesting some vegetables, especially green and leafy varieties. Although quite small, they are visible to the naked eye and must be removed. Aphids range in size from 2 -5 millimeters (1/16 - 1/8 of an inch).

The Prohibition of Eating Insects

The Torah prohibits the consumption of many types of sh’ratzim , such as insects, worms, and other “creepy crawlies”. Specific prohibitions govern those that live in rivers and lakes, those that creep on the ground, and those that fly in the air. The prohibition against eating forbidden insects is so expansive that the Talmud (Makos 16b) notes that eating even one whole insect may occasion multiple transgressions. According to the P’ri Chodosh , the reason for this extraordinary compounding of prohibitions is the ubiquity of insects and the resultant ease by which one may easily transgress this prohibition. One must, therefore, exercise great care to avoid eating foods that contain insects and thereby transgress these prohibitions. As we shall see, however, not all “insects” are created equal.

The term “She’retz ” refers to small, slithering creatures. Other creatures that are considered Sh’ratzim , notably insects, worms, and crustaceans, however, do infest food. In many cases the Torah prohibits us from eating foods that may contain prohibited Sh’ratzim .