Determination and Improvement of the Postharvest Storability of Little Mallow (Malva Parviflora L.): A Novel Crop for a Sustainable Diet

Abstract

Little mallow (Malva parviflora L.) has been traditionally used as an alternative food source. To the authors’ knowledge, there is no available published information about the postharvest storability of little mallow. This study was conducted in three steps. It aimed to determine the postharvest storability of little mallow leaves and to improve its storability using different strategies. First, the effects of four different storage conditions on the storability of little mallow leaves were tested to determine the most favorable conditions for further studies: 5 ± 1 °C and 95% relative humidity (RH); 9 ± 1 °C and 95% RH; 13 ± 1 °C and 95% RH; and 24 ± 1 °C and 55% RH as control. Preliminary experiments suggested that the best temperature and RH combination is 9 ± 1 °C and 95% RH. Hence, the effects of hot water dipping (HWD) were tested at three different temperatures (40, 45, and 50 °C) for two different durations (60 and 120 seconds); the results suggested that the 40 °C treatment is the most suitable heat treatment for improving the storability of mallow. The final experiments were conducted with 15 different treatments, including HWD, eco-friendly edible bio-materials, modified atmosphere packaging, and ultraviolet radiation. Results showed that low-density polyethylene (LDPE) (60 × 60 cm; thickness, 50 μ) and polypropylene (PP) (35 × 50 cm; thickness, 35 μ) packaging provide the highest efficacy for preserving overall quality. The edible quality of little mallow can be extended to 15 days with PP and 12 days with LDPE. However, both materials caused an abnormal odor after that time. Further studies involving additional edible coatings are necessary to determine if the storage duration of little mallow leaves could be extended.