Abstract: Embodiments of the present invention are directed to methods and devices for determining freshness of food products, and materials and devices related thereto. In some embodiments, a sensor device is provided which may include an ergonomic body including a slot for receiving a sensor card, a microcontroller, a plurality of LEDs for displaying operational status of the sensor device and/or displaying a result and audio means for audibly presenting operation status of the sensor device and/or audibly presenting a result. The device may also include a control program operating on the microcontroller for operating the sensor device and for determining a freshness of food, a first air inlet for placement proximate to a food product to receive air from around a food product for testing and a replaceable sensor card including a plurality of sensors an a sensor card inlet and a sensor card outlet.

Abstract: 2 The invention generally relates to food quality indicators and, more particularly, to improved adhesive food quality indicators and their use and manufacture. The food quality indicators (FQI) of the invention are advantageously simple and low cost but sensitive devices for detecting unhealthy levels of food spoilage products in a sealed food product package. The FQI is affixed to a breathable or gas-permeable wrap around the product, and a visual indicator region in the FQI that is sensitive to the presence of food breakdown products allows the end user, by visual observation to determine whether microbial spoilage has occurred.