What Could Be Hiding in My Romaine?

Rabbi Dovid Bistricer

I’m sure you’ve heard or even asked the following question: “Why is there such a preoccupation with the potential of finding bugs in produce these days? I don’t recall observing my grandmother checking fruits and vegetables for signs of infestation.” There are actually a number of contributing factors, including changes in diet, growing climates and the usage of pesticides; all these have impacted the likelihood of finding insects in some of the foods that we eat. So, it is worth our while to “check” into this further.

The Torah in Leviticus clearly specifies the prohibition of consuming insects that are of a size that is visible to the naked eye. In fact, the consumption of a single insect can involve a violation of as many as five or six Torah prohibitions. Since vegetables grow in the earth, they inevitably come in contact with insects; in many cases, vegetables become the insect’s home. Vegetables with cracks and crevices are more vulnerable to infestation, since these are areas for insects to become trapped or hide. Undoubtedly, this issue needs to be addressed in a serious, balanced approach.

Some consumers assume farmers and companies are wary of insects in vegetables and take proper precautionary measures. While this assumption may seem reasonable, it has proven to be untrue. The FDA tolerance levels of insect infestation in produce are far more permissive than halachic requirements. For example, the US government allows averages of up to 60 insects per 100 grams in frozen broccoli, and up to 50 insects per 100 grams of frozen spinach. Although, farmers might use pesticides to curb insect infestation levels, the effects are often limited. DDT and other highly effective previously-used insecticides have been legally banned due to associated health risks. Also, insects often develop immunity to certain pesticides over time. The rising popularity of organic produce has further complicated matters. The term organic implies the products were grown without pesticides, herbicides, and synthetic fertilizers. Consequently, organic produce could be subject to higher levels of insect infestation.

Due to seasonal influences and insect life cycles, the incidence of infestation in many vegetables varies throughout the year. The prevalence of imports, as well as many advances in produce-storage and preservation technology, results in seasonal fruits and vegetables being available throughout the year. In addition, it is often impossible to trace the origin of a particular vegetable. Broccoli sold in the New York area supermarkets may originate from Mexico one week and from California or Florida the next. One of these locations may have experienced drought conditions during the growing season. In another, unusually heavy rains may have adversely affected the crop. In the third, due to local regulations, little or no pesticide may have been applied. Without this knowledge, one may be tempted to assume that there is no need to check broccoli after having found several heads of the vegetables free of infestation the previous week. One week’s findings may tell little about the next week’s produce.

Not All Vegetables Need Checking

The requirement to check vegetables depends on the likelihood that an insect may be present.

Vegetables that are not commonly infested do not require checking.

The Halacha Recognizes Three Levels of Infestation:

1. Muchzak Betola’im—experience has shown that a certain food during a particular season is likely to contain infestation a majority of the time.

2. Mi’ut Hamatzu’i—a significant minority of samples in a particular food are expected to contain infestation. The OU accepts the position of the Mishkenot Yaakov that asserts this is at least a likelihood of 10%.

3. Mi’ut She-eino Matzu’i—it is unlikely to find infestation in a particular food. Experience has shown that at best, only an insignificant minority has proven to be infested.

We are obligated to check vegetables that fall into the first two categories, but not the third. Ascertaining whether a vegetable is subject to infestation — and thereby necessitating checking before use — is mostly determined based on experience. Several manuals and books are now available on inspecting produce and serve as excellent guides to educate the typical consumer. They include The OU Guide to Checking Fruits, Vegetables and Berries, 2nd Edition.

Bugs and Spirituality

The Torah clearly states that adherence to the stringency of not consuming sheratzim (insects) preserves the sanctity of the Jewish people. After delineating the various forbidden sheratzim, the Torah commands, ‘‘…for I am Hashem Who brought you up from the land of Egypt to be your God, and you shall be holy as I am Holy’’ (Leviticus 11:45). Rashi cites Torat Kohanim where the term ‘‘…Who brought you up from the land of Egypt’’ is analyzed. So often in the Torah, Hashem speaks of simply having brought us out of Egypt. Why with regard to forbidden insects does the Torah deviate from its usual phraseology? Based upon this inference, the school of Rabbi Yishmael taught the following lesson: ‘‘Says Hashem, ‘Had I brought the Jewish people up from Egypt for no other reason than that they should not defile themselves by eating sheratzim as the other nations do, that would have been sufficient.’” The consumption of an insect actually diminishes us spiritually. By virtue of this mitzvah, the Jewish people are raised to a unique status. Therefore, the terminology: ‘‘Hashem, who brought you up” is used. Wishing you all a bug-free Passover. And may this be the year we all “go up from the land of Egypt,” and enter Yerushalayim together.

The OU Guide to Checking Fruits, Vegetables, and Berries, 2nd Edition, may be purchased by contacting Shop OU at 212.613.8385, or

fn1. Food, Drug, and Cosmetics Act 402 (a)(3)

How to Check RomaineRomaine lettuce is commonly used for maror. This lettuce type is known as an open leaf variety. This means that as they sprout forth from the ground, the leaves begin to open up like a flower. Toward the end of their growth, they begin to close around the stalk. Since romaine lettuce grows open, it is much more prone to insect infestation throughout the head than other varieties of lettuce that primarily grow as a closed ball.

The insects most commonly found in open leaf lettuce are small black or green aphids and thrips. The leaves of the vegetable often camouflage these insects. The open structure of these vegetables allows insects to penetrate the entire head. Often, insects may be found between the innermost layers of leaves of an infested head. Therefore, each leaf must be washed and checked individually. The use of a light box for checking lettuce can be extremely convenient and helpful. However, even if a light box is not used, it is crucial to examine both sides of each leaf against a good source of light.

Checking for insects

Below are step by step recommendations for how to properly check romaine lettuce for insects:

1. Cut off the lettuce base and separate the leaves from one another.
2. Soak leaves in a solution of cold water and soap. The proper amount of soap has been added when some bubbles are observed in the water.
3. Agitate lettuce leaves in the soapy
4. Spread each leaf, taking care to
expose all its curls and crevices. Using a heavy stream of water or sink hose, remove all foreign matter and soap from both sides of each leaf. Alternatively, a vegetable brush may be used on both sides of the leaf.
5. Leaves should be checked over a light box or against strong overhead lighting to verify that the washing procedure has been effective. Pay careful attention to the folds and crevices in the leaf where insects have been known to hold tightly through several washings.

Occasionally, worms may be found in burrows within the body of the leaf. Look for a narrow translucent burrow speckled with black dots breaking up the deep green color of the leaf. These burrows will often trap the worm within the leaf. To rid the leaf of these worms, carefully slit the bumpy part within the burrow with a sharp knife and remove the worm. It is important to note that many of these varieties feature curly leaves with many folds in which the insects tend to hide. It is therefore recommended that they be washed and checked with particular caution.

Rabbi Dovid Bistricer

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