Why Wash Cantaloupe and Watermelon Before Cutting Them?

Washing fruit that you peel before eating may seem unnecessary; after all, the rind will not go on the plate. But when you cut the fruit in half with a knife, the knife first passes through the rind and carries whatever is on it directly inside. The same path is opened again with every slice. So even though you do not eat the rind, the dirt, dust, and microorganisms on it reach the edible flesh. Washing is about the path the knife makes, not the rind itself. The same reasoning applies to foods such as zucchini, cucumber, and citrus fruit, where the knife cuts through the peel.

Cantaloupes and watermelons are a special case in this respect. Both grow lying directly on the soil and remain in contact with it until harvest. Their rinds are rough and porous; even the smooth-looking surface of a watermelon has microscopic openings, while a netted cantaloupe rind cannot be cleaned without a brush. During storage and transport, they pass from crate to crate and hand to hand. Their being stacked on top of one another at the grocery store adds to this burden, too. Whole fruit left on the counter at home also picks up contamination from the surface underneath it.

The second factor is the fruit itself. Cantaloupe and watermelon flesh is juicy, sweet, and low in acid; that is, it provides a favorable environment for bacteria to multiply. When whole, the rind is a barrier; once cut, that barrier is gone. Do not leave cut cantaloupe or watermelon at room temperature for more than 2 hours; above 32°C / 90°F, the limit is 1 hour. Holding it on ice provides safe cold holding only while the fruit stays at 4°C / 40°F or below.

The washing method is simple. Hold the fruit under cool running water and scrub the entire surface with a clean produce brush; do not use soap, detergent, or bleach. The stem scar and blossom end hold the most dirt, so brush those areas separately. After washing, dry the fruit with a paper towel, because water running off the wet rind can enter inside along with the knife. Cut it only after drying. Use the brush only for this purpose, and wash and dry it after every use.

Timing matters, too. Do not wash fruit as soon as you bring it home and then store it; moisture left on the surface creates favorable conditions for mold and decay. Wash it just before cutting. Put cut slices in a covered container in the refrigerator and eat them within a few days. As soon as cutting is finished, wash the knife and cutting board with hot, soapy water; do not skip this step if you are going to chop another food with the same knife afterward. Do not leave rind pieces on the counter; throw them away directly.