IntroductionFruit ripenening in general is a natural physiological process which makers the fruits edible, nutricious and palatable. However nowadays the market is generally flooded with fruits ripened articifically using a chemical known as calcium carbide. Artificial ripening is resorted to by the unscrupulous mechants with a view to achieve faster and more uniform ripening characteristis. The most common examples of fruits and vegetables artificially ripened using calcium carbide are mango, banana, papaya and sometimes sapota (chiku), dates and tomotoes. However use of calcium carbide for artificially ripening the fruits are associated with serious health hazards. In this article the potential harmful effect of use of calcium carbide for artificial ripening of fruits and the precautions to be taken for preventing the same have been discussed with a view to create awareness about the issue.
Natural ripening of fruitsRipening causes fruits to become more palatable. The ripening of fruits involve softening, enhanced sweetness, decreased bitterness and changes in color/appearance. However only climacteric fruits continue to ripen after being picked. Some of the common examples of such fruits are mangoes, apples, bananas, melons, apricots and papaya etc. The non-climacteric fruits can ripen only on plants and therefore have shorter shelf life on being harvested after ripening. The typical examples of such fruits are grapes, citrus fruits and strawberries. During the process of ripening, enzymatic breakdown and hydrolysis of polysaccharides like strach takes place. The hydrolysis causes the starch to break down into smaller molecules like fructose, glucose and sucrose etc.
Fruit ripening agentsRipening agents speed up the process of ripening of fruits after they are picked prior to full ripening. Ethylene gas is one such common ripening agent. Bananas are picked when they are hard and green and shipped to the distant places. After reaching the destination, the bananas are gassed with ethylene to artificially ripen the same. Ethylene is produced chemically in catalytic generators and ethylene sensors are used to precisely control the amount of the gas. However a chemical known as calcium carbide is most commonly used for artifcial ripening of fruits. It releases acetylene gas which has effect similar to that of ehtylene gas and causes artificial ripening of fruits.
Artificial ripening of fruitsUnsaturated hydrocarbons like ethylene and acetylene speed up ripening process and cause cosmetic color changes in fruits to impart them a ripened look. However the organoleptic properties of the fruits i.e. what the individual experience through senses like taste, sight, smell and touch etc. gets impaired considerably. Generally the harvested fruits are subjected to the treatment of ripening agents by illerate people without taking into consideration the maturity status of the fruits and the quantity of ripening agent used is often more than the quantity required to achieve only desired cosmetic appearance.
Calcium carbide as a ripening agentThe most commonly used artificial ripening agent is calcium carbide which is commonly known as masala. It is a chemical compound and is produced on industrial scale by heating a mixture of lime and coke in an electric arc furnace. It is used for production of acetylene gas. The technical grade of calcium carbide available in market generally contains 80 - 85% of calcium carbide and comes in the form of grey or brown lumps/pieces. In presence of moisture, the technical grade calcium carbide produces garlic like smell. On reaction with water, calcium carbide produces acetylene gas which causes the fruits to ripen. The action of acetylene gas on fruits is similar to action of ethylene gas on fruits. However the acetylene gas so produced contain traces of arsenic and phosphorus hydride as impurities which are primarily responsible for harmful effects on health.
Possible adverse health effects of calcium carbide
How to identify
Legal provisionThe Food Safety and Standards Act, 2006 and the Food Safety and Standards Rules , 2011, Food Safety and Standards (Prohibition and Restriction on sales) Regulation, 2011 and Food Safety and Standards (contaminants, toxins and residues) Regulation, 2011 framed thereunder, contain related legal/statutory provisions. These regulations are made available on the website of the Food Safety and Standards Authority of India (FSSAI) - http://www.fssai.gov.in/. Any problem related to food safety can be reported to the Commissioner of Food Safety of the concerned state.
ConclusionThe fruits ripened artificially with calcium carbide can be identified by examining the same carefully at the time of buying the same. However, sometimes it may not be possible for all the buyers to identify such fruits. Therefore it is imperative that the due precautions should be taken before eating the same. As far as possible the fruits should be peeled before consumption after washing the same thoroughly for few minutes under running potable water.