"Fruit ripeness detection using RediRipe©, LLC stickers"
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Abstract: Ever have a hard time deciding which fruit for purchase in a grocery store is going to be ripe and ready for a bite?  Selecting fruit is more of an art than a science as the indicators of fruit maturation are hard to evaluate.  The goal of this research program is to develop a simple and inexpensive device to detect release of ethylene from ripening fruits and vegetables to provide a noninvasive means to evaluate ripening.  This device could be used by growers, packinghouses, shippers, grocery stores, or consumers. 

Growers and grocers throw out large amounts of fruit each year because it ripened and hence rotted faster than it could be sold.  consumers, with no simple way to tell whether fruit that looks good on the outside will taste good on the inside, often buy peaches, pears and avocados they can't eat because they're under- or overripe.  We have designed a sticker based device that presents a gradual color change indicative of the amount of ethylene released by an individual fruit.  the device is a flat, inexpensive, micro-thin permeable membrane sandwich in the form of a patch or “sticker” that self-adheres to the surface of a fruit.  The patch detects the emissions of ethylene from an individual apple (rather than the atmosphere around many apples) and consequently displays a color change indicating ripeness on the visual (external) surface of the detector.  Ethylene is a demonstrated fruit ripeness indicator and its release correlates with ripening.