For our customers

Q．I want to use WonderKeep®. What should I do?

A．Please ask our agent to help you choose the exact type of WonderKeep® to suit your product’s needs.Please feel free to contact us.

Q．After the bag of WonderKeep® has been opened, the WonderKeep® sachets get hot.

A．The self-reacting type of WonderKeep® produces heat, resulting from a chemical reaction of the main ingredient when it is exposed to the ambient air. We suggest you disperse the WonderKeep® sachets on a tray or other work surface. If the oxygen absorbers are a belt type or a roll type, please use them within the specified maximum exposure time.

Q．I want to use WonderKeep® in small quantities each time.

A．Each time you open the outer bag, the WonderKeep® will be exposed to the ambient air, causing use of the oxygen absorber. So, please have available smaller packages with a high oxygen barrier and place small portions of WonderKeep® in them and seal them using a vacuum sealer. This way, you can use the WonderKeep® over time without exposing them to the air.

Q．The food package with WonderKeep® inside bulges.

A．It may be that carbon dioxide gas is being generated by rotting food. Yeast fungus can propagate even in an anoxic environment, which WonderKeep® cannot prevent from happening. In such a case you need to reduce water activity in the food or store it in a cool, temperature-controlled place.

Q．Can I use WonderKeep® on frozen food?

A．Please use the ferrous type of WonderKeep®. However, as the temperature drops, WonderKeep® takes longer to absorb oxygen. Below the freezing point, its absorption slows markedly. You can maintain the absorption capability if you refrigerate the food package with WonderKeep® or leave it at room temperature for approximately 12 hours before freezing. WonderKeep®’s absorption rate returns to normal at room temperature.

Q．Can I use WonderKeep® in a vacuum-sealed (degassed) package?

A．If the package is packed loosely enough for the air to move freely inside the package film, yes. In a strong vacuum, WonderKeep® may be packed too tightly with the food or packaging film, or a small air pocket may form in the package. In that case, no. WonderKeep® cannot properly absorb the oxygen and the food may decay.

Q．Can I use WonderKeep® in a nitrogen gas flush package?

A．Yes, you can. Please select the proper type of WonderKeep®, taking into account variation in the gas exchange ratio. However, using carbon dioxide gas for gas flushing is not suitable because it adversely affects the absorption capability of WonderKeep®.

Q．Can I use WonderKeep® with desiccants?

A．It is not advisable to use WonderKeep® with desiccants because they will absorb the moisture needed for WonderKeep® to self-activate. It is recommended to separate WonderKeep® from the desiccants with a tray or the like in the food package to avoid contact.

Q．Can I heat-sterilize the food package with WonderKeep® inside?

A．Because heat treatment may have detrimental effects on WonderKeep®’s oxygen absorption, depending on the heating conditions, or may cause content seepage into the absorber casing or breakage of the casing, leaking the contents, it is strongly recommended that you conduct sufficient testing to determine whether to apply or not.

Q．Even if WonderKeep® is used, the blue color of WonderSensor® won’t turn to pink. What happened?

A．Please contact us. We will check the probable causes such as a minute hole, seal defect, or poor gas barrier function of the package film, along with the moisture or gas conditions inside the package.

For Consumers

Q．I mistakenly swallowed a WonderKeep®. What should I do?

A．The ingredients of WonderKeep® have been proven safe through acute oral toxicity testing by specialized laboratories. Even if it is swallowed as is or it is cooked and eaten with food you will be safe. Should you feel ill by any chance, please seek medical advice.

Q．When taking the WonderKeep® out of the package of food, it feels hot. Is that normal?

A．When opening a package, the WonderKeep® sachet is exposed to the ambient air, causing a rapid oxidation reaction and you will feel some heat. This is nothing to be concerned about as the heat usually dissipates in a short time and will not cause a fire.

Q．Can I heat a food package with the WonderKeep® in a microwave oven?

A．Please do not heat a food package with the WonderKeep® in a microwave oven; the absorber casing may explode and spill the contents. Also, there is a danger that the WonderKeep® may catch fire. Please make sure you heat the food package after you remove the WonderKeep® from it.