RADIOISOTOPES

In many countries, lemons are waxed for post-harvest protection. However, in Japan, lemons are typically sold unwaxed because they are a special domestic product whose peels are often consumed directly or used in cooking. This practice poses issues for Japanese-island-grown lemons, which may require a minimum of one week for transport. Unwaxed lemons are generally susceptible to mold contamination and have a short shelf life of only two weeks, making their transportation from the island to the mainland impractical. To address these issues, we developed an irradiation-based method that uses soft (low-energy) electron beams (EBs) to exclusively sterilize mold on lemon peels. Thereafter, we investigated the effect of the treatment on the shelf life of the lemons by uniformly irradiating them with EBs. The results revealed that while the proposed electron irradiation sterilized the mold, it triggered the browning of the lemon peel, rendering the method unsuitable for long-term storage.