Burying fruits in ash, sand or sawdust delays ripening.

    Dr Abe V Rotor

In the countryside where there are no modern facilities for storage, farmers have devised methods of storage to increase the shelf life of fruits, and allow them to ripen properly. One method is to cover the fruits, such as tomatoes, mango and bananas with ash or sawdust.

Still life in Pastel, by Anna Christina Rotor 

To show the effectiveness of this practice, scientists at UPLB stored tomatoes (Pope variety), for the duration of one to two weeks, in rice hull ash in two preparations – one moist and the other dry.  Tomatoes stored in dry ash ripened faster, while tomatoes stored in moist ash ripened slower and showed a more uniform and deeper red color.  The tomatoes were also heavier and firmer than those stored in dry ash.  Tomatoes that were simply stored by piling suffered significant losses and that ripening was uneven. The colors of the fruits were pale red and predominantly yellow.

It was an old practice I observed among vegetable traders who ship green Pope tomatoes grown in Claveria (Cagayan de Oro) all the way to La Trinidad Valley in Benguet by boat and truck. The tomatoes were laid open in the cool air, until they ripened into bright red color.  They were then individually wiped with waxed cloth, assorted and returned to their crates and marked Baguio Tomatoes. Tomatoes that ripened on the way, which normally takes about a week, turned into yellow to orange color and were priced much lower than those ripened in the cool highland air.

We can only imagine the high cost and difficulty of shipping the fruits all the way from Mindanao via Manila pier to the Benguet, then transporting the commodity back to Manila where they are sold. Now there is a substitute to this practice.  Tomatoes can be delayed in ripening and that they ripen uniformly into red color when stored in moist rice hull ash. ~