A Natural Component-Based Oxygen Indicator with In-Pack Activation for Intelligent Food Packaging

Abstract

Intelligent food packaging can provide consumers with reliable and correct information on the quality and safety of packaged foods. One of the key constituents in intelligent packaging is a colorimetric oxygen indicator, which is widely used to detect oxygen gas involved in food spoilage by means of a color change. Traditional oxygen indicators consisting of redox dyes and strong reducing agents have two major problems: they must be manufactured and stored under anaerobic conditions because air depletes the reductant, and their components are synthetic and toxic. To address both of these serious problems, we have developed a natural component-based oxygen indicator characterized by in-pack activation. The conventional oxygen indicator composed of synthetic and artificial components was redesigned using naturally occurring compounds (laccase, guaiacol, and cysteine). These natural components were physically separated into two compartments by a fragile barrier. Only when the barrier was broken were all of the components mixed and the function as an oxygen indicator was begun (i.e., in-pack activation). Depending on the component concentrations, the natural component-based oxygen indicator exhibited different response times and color differences. The rate of the color change was proportional to the oxygen concentration. This novel colorimetric oxygen indicator will contribute greatly to intelligent packaging for healthier and safer foods.

Food Sensors: Challenges and Opportunities

“…Recent advances have focused on in-pack activation of redox dye sensors as they cannot be exposed to the atmosphere before use. [59,64,65] Ageless Eye is a commercial oxygen indicator developed by Mitsubishi Gas Chemical Company Inc., consisting of a redox dye and strong reducing agents. [66] The O 2 concentration can be determined by naked eye observation of the sensor's colorimetric signal.…”

An overview of smart packaging technologies for monitoring safety and quality of meat and meat products

“…Exposing the O 2 indicators to UV‐light also showed to be an effective way of protecting these indicators . Won et al developed O 2 indicator based on natural components (laccase, guaiacol, and cysteine) which is characterized by in‐pack activation. The orthodox O 2 indicator comprising artificial and synthetic constituents was remodeled using these natural compounds.…”

Preparation, Characterization and Application of a Low Water-Sensitive Artemisia sphaerocephala Krasch. Gum Intelligent Film Incorporated with Anionic Cellulose Nanofiber as a Reinforcing Component

“…However, these indicators can pollute packaged food and may pose a harmful risk to the ecosystem and people's health [10]. To resolve those issues, natural indicators, such as curcumin [11][12][13], anthocyanins from black carrot [14], red cabbage [15,16], purple-fleshed sweet potato [17], and roselle [18], have been used to replace synthetic indicators in edible intelligent packaging films according to recent reports [19], because they are non-toxic [20] and…”