From the Tolaim Lab – Bagged Lettuce

IN ALMOST ANY supermarket, one can purchase bagged lettuce—such as iceberg or romaine—labeled “washed and ready to eat” or “triple washed.” This raises the question of whether one may rely on the manufacturer’s washing methods or must still be concerned about insects.

This is complex. Washing practices vary widely between companies, with different machinery, procedures, and quality standards. While some systems may be effective, others are not, and the consumer has no practical way of knowing which meets halachic requirements. The default assumption must be that these products have not been washed sufficiently from a halachic standpoint.

The types of insects manufacturers generally seek to remove, and the levels they deem acceptable do not necessarily align with Halacha. In addition, washing systems often lack fine filtration, allowing insects that were removed to remain in the water and be reintroduced. For this reason, the label “triple washed” is not, by itself, a guarantee.

Some suggest distinguishing between iceberg and romaine lettuce, arguing that iceberg is generally less infested and that commercial washing should therefore suffice. However, our experience does not support this. Testing has shown that even iceberg lettuce—and even shredded cabbage—can contain insects when sold prewashed and bagged.

Accordingly, OK Kosher does not recommend using prewashed, bagged lettuce unless it bears a reliable
hechsher or is checked at home like any other leafy green. In all OK Kosher–supervised food-service establishments, bagged lettuce of any kind is not permitted unless it is certified by a reliable agency or thoroughly checked on site by the mashgiach using a thrip cloth and lightbox.