A recent surprise inspection by the food and drugs administration (FDA) at the sub-market yard at Mapusa led to the seizure of 180kg of mangoes after it was found that the boxes in which the fruits were stored also contained sachets of ethylene ripener. The action came after the FDA inspected seven units at Siolim engaged in selling local mango varieties and eight at the Mapusa sub-yard dealing in varieties brought in from other states. Stock was seized from two units at the Mapusa yard as officials noticed some suspicious material. Twenty-four samples of the fruit were subsequently sent for a chemical residue analysis and to determine if they were being ripened by way of unapproved methods. Results are expected shortly, FDA officials said.
The consumption of fruits has increased considerably in recent years due to the myriad health benefits they provide and also due to their availability round the year. However, highly perishable fruits like mangoes, papayas and bananas cannot be transported long distances after ripening as they tend to spoil. To avoid spoilage while moving and storing such fruits, traders generally harvest raw fruits and ripen them artificially just before sale. This process involves controlled ripening so that the fruits ripen faster and uniformly, thereby achieving the desired characteristics intended for better consumer acceptance and improving sales.
According to the Food Safety and Standards Authority of India (FSSAI), the use of ethylene gas at a concentration of up to 100ppm (parts per million) is permitted for artificial ripening of fruits. While ethylene gas can be generated from various sources, it is comparatively more expensive, which is why many traders often resort to using unsafe and banned ripeners. The industrial-grade calcium carbide is often used to release acetylene gas for artificial ripening mainly of mangoes, bananas and
papayas.
The use of calcium carbide may be a quick fix for many traders looking to preserve their stocks of fruits and ensure maximum demand and sales, but this chemical has traces of arsenic and phosphorus, which is harmful to humans. Potential side-effects upon consuming fruits laced with calcium carbide include dizziness, frequent thirst, irritation, weakness, difficulty in swallowing, vomiting, and skin ulcers. Also, acetylene gas released from calcium carbide is equally harmful for handlers.
Ethylene, on the other hand, is a hormone naturally produced within the fruit and regulates fruit ripening through a series of chemical and biochemical activities. The treatment of unripe fruits with ethylene gas triggers the natural ripening until the fruit itself starts producing ethylene in large quantities.
There are certain requirements if fruits are to be ripened using ethylene. Firstly, an airtight room, preferably an insulated one for better temperature control, is a must. A temperature regulation system to keep the fruit stocks either warm or cool - depending on the climate of the area - needs to be installed. There also has to be a humidity regulation system and proper air circulation and ventilation. Fruits should be kept in ventilated plastic crates or stackable fruit boxes inside the ripening chamber. These boxes or racks should be stacked in such a way that there is at least a minimum of 4-6 inches of space from the walls and between the adjacent crates. To ensure uniform ripening, maintaining airflow throughout the chamber is critical. Also, the fruits stacked for ripening should not occupy more than 75% of the volume of the chamber (as well as the crate) during the process.
While it is best to allow fruit to ripen naturally by harvesting them at optimum maturity, wrapping them individually with paper, or by arranging them in layers over paddy husk, wheat straw, or inside an airtight rice bin, these options are usually cumbersome and time-consuming, particularly when fruits are mass-produced for large-scale sale.
Nevertheless, there are certain telltale signs that a fruit has been artificially ripened, which consumers need to be aware of if they intend to steer clear of such fruits. To begin with, artificially ripened fruit will have a uniform skin colour. Also, they are generally found to have lesser flavour and a shorter shelf life.
Another clear sign that a particular fruit has been artificially ripened is if they are available much before the season in which they naturally grow.
So, before one decides to gorge on those enticing, sunset yellow mangoes, it would be prudent to ensure that they are purchased from reliable or known vendors and not the many sellers who emerge by roadsides selling heaps of the King of Fruits from out of a van. It is better to be safe than sorry.