What are Oxygen Scavenger / Absorbers? : Little Food Rescuers !!!

 

Oxygen Absorbers: Little Food Rescuers !!!

Ever wondered what those additional small little pouches are? And why they are kept inside the food packets?

 So let us dig in to know more about these little food savers and their role in food packaging.....

The small oxygen absorber sachets are printed as 'oxygen absorber' on them. 

(Not to be confused with the silica gel pouches, since they look quite similar, always check the mentioned printed name on the sachet.) 

The oxygen absorber sachets essentially help in removing the oxygen from an enclosed food packet to preserve food quality.

What is an oxygen absorber? How do Oxygen absorbers work? 

Oxygen Absorbers or Oxygen scavengers

The small sachets of the oxygen absorber usually contain a mixture of iron powder, natural zeolite clay and other ingredients like salt in the granular powder form. 

This oxygen absorber requires and works in the presence of moisture (humidity) hence the clay avails the required moistness and the iron powder activates in the presence of salt to absorb the oxygen. 

Essentially the oxygen absorbers only absorb oxygen and do not absorb moisture.

 

Why Oxygen?

Oxygen is one of the primary components that cause food degradation, which affects flavor, color, smell, and texture, as well as a nutritional value such as deteriorating vitamins in food. 

Aerobic microorganisms – such as bacteria, mold, and fungi – require moisture to form and thrive, which ultimately causes food spoilage.

 Oxygen as gas is a highly reactive element. Food products exposed to oxygen for a longer period tend to cause; rancidity (in presence of fats), browning (e.g., oxidizing in case of fruits like an apple), softening of sugar-based confectionery; and may lead to microbial spoilage as well. 

Hence removal of this element becomes an essential part of the food storage process to increase the shelf-life. 

To aid the removal of oxygen from the packaged food the methods like vacuum packaging and modified atmosphere packaging (MAP) like nitrogen flushing (pillow packing) are commonly practiced in food industries. 

Though for example, in the case of nitrogen flush packaging, there is an approx. 0.22 % trace amount of oxygen that gets trapped inside the pack that might affect the food quality during storage. Here, these oxygen absorber sachets come in handy.

 

 How do oxygen absorbers help preserve food products?

Application of Oxygen absorber (OA) in food :

 It is a food packaging technique, also called active packaging; oxygen scavenging packets absorb available oxygen inside the food packet or container to preserve and maintain the food product quality that eventually prolongs its shelf life, and reduces the loss of food from spoilage. 

The Oxygen absorber sachet removes the oxygen by absorbing it and releases nitrogen gas that is neutral and helps in preserving food creating the anaerobic condition inside the food packaging. 

This stabilizes and maintains the organoleptic characteristics of the food like taste, flavor, texture, and keeps it fresh preventing it from rancidity and microbial spoilage like mold. It ultimately increases the shelf life of packaged goods.

Why oxygen absorber?  

To control the humidity level inside the packed food it is suggested to use an oxygen absorber. Along with the temperature factor, the food packaging and its storage should be done in a humidity-controlled atmosphere as it may affect the food product texture during storage.

In the case of nitrogen flush packed product, over time, there are chances of oxygen leakage into the packet through the seal. 

The oxygen absorber pouch will absorb the available traces of the oxygen left inside the nitrogen-flushed pack. 

The oxygen absorber sachets are available in different sizes and dosages. Their dosage is represented as the ‘CC’ unit. They are available in dosages ranging from 20CC to 500CC sachets as required. 

As these come in small pouches with different sizes and dosage, their requirement varies depending on several factors. 

The required dosage of the oxygen absorber pouch depends on the following parameters:

• The type of food product and its product packing quantity. 

• The packaging material used, e.g., glass jars, polyethylene (HDPE, LDPE), MYLAR bags. And its dimension,e.g., Packaging bag size.

• The OTR (Oxygen Transmission Rate) and the MTR (Moisture Transmission Rate) of the packaging material.

• The packaging method used, e.g., airtight packing, nitrogen flush packing, or vacuum packing. 

•  The humidity level and the ambient temperature during the food packaging.

• The bandwidth of the bag, seal determines the strength of the sealed package. The required width of the seal ranges to a few mm eg., 3-4mm.

To note that their potential for preserving food is limited depending on the dosage used. After absorbing a certain amount of O2, it gets exhausted. Hence it works as a supplemental preserving method to the primary packaging of the food. 

Though these above-mentioned parameters are for the knowledge purpose, where these are considered to finalize a commercial product packaging and to attain certain desired results to enhance the shelf life of the food product. 

For at-home purposes for the storage of grains, cereals, dry fruits, dehydrated products, spices, etc. you can toss in average size (50cc to 100cc) sachets of oxygen absorber for small-sized packets (of around 1kg) or jars. For 4kg to 5kg size packets require around 300cc to fulfill your needs.

 

 How to determine if its Food-safe or not:

These pouches are commonly available on e-commerce websites like amazon. To find out whether it is food safe, check the information provided for it. 

Information on if it is FDA (Food & Drug Administration) approved or not, the food safety compliance documents and COA (certificate of analysis) of the product can also be checked from the vendor, if possible.

The food-safe grade sachets make use in direct contact with the food products. 

The contents of The oxygen absorber pouch are not edible. The packaging material of the sachet  comes in direct contact with the food with properties such as the non-tearable and non-adhering properties similar to Tyvek fabric determine the food safety of the sachet. 

This food-safe packing enables the transfer of humid air and oxygen to enter inside by protecting the inside contents from spilling out.

 

How to use oxygen absorber sachets in food: 

Based on the primary packaging material or the packaging method used among the nitrogen flush packing(pillow pouch), vacuum packing, or airtight jar packing work on the principle of removing the oxygen from the pack or container, though the trace amounts of oxygen get trapped inside. And the sealed side of the packaging tends to leak over time. 

• Use a food-safe oxygen absorber sachet, to use in direct contact with food. Expose the oxygen absorber pouches in a tray to the ambient environment for not more than  5-10 minutes.

These activate the oxygen absorber sachet as they shift from vacuum-sealed packaging to a different environment. These sachets slightly heat up and feel warm upon touch.

• Once they are activated, put this sachet in a food packet or container (jar) and seal it. 

• The sachet should remain close to the seal at the top and not be submerged inside the product. It will aid in oxygen removal during storage if in case the seal starts to leak.

 

 How to check the expired sachets:

The contents of the new oxygen absorber sachet have a soft, granular mix. It turns into a hard lump after the oxygen absorber sachet is exhausted.

 

How to store the unused oxygen absorber sachet:

The new batch of oxygen absorber sachets is usually vacuum-seal packed. 

After using the required no. of sachets, the remaining unused sachets should be sealed immediately in their original packaging by manually removing the air from the pack and keep it in an airtight container. 

What to avoid:

Do not expose oxysorb sachets (more than required) for too long outside as they get activated in the presence of oxygen. Otherwise, discard them.

Never shuffle the vacuum seal-packed oxygen absorber sachets as it will displace the pouches to pile up on each other inside the pack and activate them. 

All plastic bags, regardless of any plastic barrier material, it's made, slowly the oxygen starts leaching into them. 

The un-used oxygen absorber sachets generally have about 12 – 18 months shelf life. But just by sitting on the shelf, they lose their approx. 90% capacity if not used soon. 

So make sure to stock a fresh batch and utilize them as early as possible.

 Precautions while using oxygen absorbers :

The sachets of oxygen absorbers are not edible. Hence it is printed with the precautionary note on them saying 'DO NOT EAT'. 

Once the sachets are exhausted should be thrown into the dustbin.

 The oxygen absorber pouches contain an iron powder that is toxic upon consumption. The food-safe packaging material of the sachet of oxygen absorber is considered non-toxic.

But in most circumstances, these oxygen absorber pouches are mistakenly consumed by pets through feeding packaged pets or other foods (in which these pouches are added). 

Hence care should be taken while handling these sachets used food products as these are small in size and unknowingly consumed may cause choking, which is lethal to health.

 

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Always CraveDip☺!!!