Abstract: A method for detecting a food allergen, the method may include (a) exposing a sensor to vapors emitted from food, wherein the sensor comprises one or more conductive paths that comprise one or more adsorbing portions that are configured to adsorb one or more volatile indicators that differ from the food allergen and are emitted from a food component that comprises the food allergen; wherein an impedance of the one or more adsorbing portions is responsive to an adsorption of at least one volatile indicator of the one or more volatile indicators; (b) measuring the one or more impedances of the one or more adsorbing portions to provide sensed information; and (c) determining a presence of the food allergen in the food, based on the sensed information.

Abstract: A system comprising: (a) a transmitter adapted to provide an audio signal output comprising an embedded data element imperceptible to a human being of normal auditory acuity when said audio signal output is played through speakers wherein said embedded data element is embedded using phase modulation; and (b) an audio receiver adapted to receive said audio signal output and extract said embedded data element and respond to at least a portion of the data in said embedded data element.