What is the big deal about ethylene anyway?

Ethylene gas (H2C=CH2) is a harmless odorless, colorless, gas that is produced from both natural and man-made sources, and that has a profound effect on the freshness of produce. As is so often the case, ethylene's effects on produce was discovered by accident. For years, lemon growers had stored newly harvested green lemons in sheds kept warm by kerosene heaters until they turned yellow and ripened enough to deliver to market. When new electric heating systems were installed, the lemons no longer turned yellow on time. Investigation soon found that the critical factor in the ripening process was the ethylene gas given off by the burning kerosene in the heaters. In fact, it was discovered that fruits and vegetables actually produce ethylene as they ripen. The ethylene acts as a signal to other plants to synchronize ripening to maximize their appeal to their seed disseminators (e.g. birds), thus assuring the dispersal of their seeds. Scientists have since studied the effects of ethylene on produce and found that the effects are widespread. Other plant tissues can produce this gas, as well. Even after harvest, fruits, vegetables and flowers are still alive, continuing their biochemical processes, including ripening and the generation of ethylene. Bruising or cutting some fruits and vegetables can even cause them to increase their ethylene production. Since the discovery of the relationship between ethylene gas and the ripening process, industry has developed technology to manage the amount of ethylene gas in order to accelerate or slow down ripening and spoilage. Commercial warehouses, ships and trucks are nearly all fitted either with ethylene absorption technology or ethylene generation machines. However, when you buy fruits and vegetables and bring them home they sit on your counter or in your refrigerator where ethylene gas accumulates and accelerates the ripening process. You probably live in one of the numerous households that experts say throw away over $600 worth of produce per household each year due to accelerated spoilage from ethylene gas. The HEALTHY HARVEST FRESHNESS EXTENDER has been developed in partnership with leading industry experts in order to bring industry technology to your home, save you money and benefiting the environment. The HEALTHY HARVEST FRESHNESS EXTENDER has been thoroughly tested and the active ingredient is registered with the Organic Materials Review Institute. How does the HEALTHY HARVEST FRESHNESS EXTENDER work?  The ethylene gas molecule is very reactive and is readily oxidized into a state that renders it harmless to fruits and vegetables. The simplest and safest method of removing ethylene is to “oxidize” it with potassium permanganate. Oxidation refers to a method of changing a molecule to something else. Potassium permanganate (KMnO4) is a safe, inert compound used in a number of familiar applications, such as in drinking water treatment systems, and combined with ethylene it reacts and changes into a harmless potassium oxide (a sort of “rust”) and carbon dioxide. An Effective Carrier Medium Potassium permanganate is a safe and effective oxidizer, but we still need a way to deliver it to where ethylene gas exists. We need a carrier medium that will allow the ethylene to contact the oxidizer so it may be reacted away. Industry does this in several ways, or course, but the HEALTHY HARVEST FRESHNESS EXTENDER uses natural clinoptilolite, commonly known as zeolite.  Zeolite is actually ancient volcanic ash that has been turned to rock over eons. Although there are several forms of zeolite, the HEALTHY HARVEST FRESHNESS EXTENDER is made with an exceptionally pure form that is highly porous and possesses a very high surface area. When the potassium permanganate is applied to this pure zeolite using a special patented process, the result is a highly effective ethylene absorber that also has an extremely long life. The HEALTHY HARVEST FRESHNESS EXTENDER has the highest percentage of available reactant and the longest life per gram of any other ethylene absorption product, because the The KMnO4 impregnated zeolite is then packaged in special membrane packets that are water resistant, but are highly permeable to ethylene, and these packets are then encased in patented plastic shells in order to maximize airflow into and around the packets. Each HEALTHY HARVEST FRESHNESS EXTENDER is designed to last three months assuming a typical household volume of produce use. We recommend that two Extenders be used at the same time for a typical household in order to maximize the absorption effectiveness, though for smaller households one Extender may provide ample protection. Refill kits are available from our website or from your local store. Don't throw the spent material away ! We recommend that you put the spent zeolite in your houseplants or in your garden.  The zeolite is a natural soil and the residual MnO2 provides trace minerals to the soil. Your plants will love it. What is the specific chemistry of the reaction? For all you chemists out there, the balanced chemical reaction is as follows: 3CH2CH2 + 2KMnO4 + H2O = 2MnO2 + 3CH3CHO + 2KOH 3CH3CHO + 2KMnO4 + H2O = 3CH3COOH + 2MnO2 + 2KOH 3CH3COOH + 8KMnO4 = 6CO2 + 8MnO2 + 8KOH + 2H2O Combining chemical equations 1-3, we get: 3CH2CH2 + 12KMnO4 = 12MnO2 + 12KOH + 6CO2 Even if the reaction does not go all the way through to the carbon dioxide-producing step, many of the intermediate products formed either become irreversibly bound to the media or act as reactants themselves. Such is the case of the potassium hydroxide (KOH) formed in equation 1 and 2. The KOH will react with the acetic acid formed in equation 2 to produce the potassium acetate salt (KCOOCH3) through a simple acid-base neutralization reaction. This is shown below. CH3COOH + KOH = KCOCH3 + H2O Combining equations 1, 2, and 5 we get: 3CH2CH2 + 4KMnO4 = 3KCOOCH3 + 4MnO2 + KOH + H2O Be sure to contact us if we can answer any additional questions!