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Less shrinkage due to ethylene-induced ripening. Protect your fruits.

Acitvated alumina oxidizes ethylene and helps delay the premature ripening of fruits along supply chains. 

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Poresphere Aktiv-AL K8 purple granules in petri dish

What ethylene does to your goods.

Uncontrolled accumulation

Ethylene is released during the natural ripening process of fruits. In sealed packaging, it accumulates and accelerates the ripening of nearby goods.


Loss in quality and shrinkage

The consequences are significant losses in quality due to premature ripening and potential losses of corresponding quantities of fruits that become overripe and  no longer meet quality standards.


Supply chain responsibility

In multi-stage, long-distance supply chains, an accelerated ripening process quickly becomes a major problem that can result in entire batches being rejected. This increases the pressure on you, as a supplier, to guarantee the quality of your goods.

Oxidize ethylene before it`s too late. 

When ethylene gasses out uncontrolled you will find yourself in a vicious cycle.

The fruits perceive the accumulated gas as a signal to ripen and stimulate each other's ripening in an exponential manner producing more ethylene ending in a chain reaction.

Your goods will be overripe or gone bad by the time they reach the end consumer if you don`t stop the process. 


To stop the cycle. you will need to prevent the accumulation of ethylene in your transport or storage containers. 

Silica Gel Orange
Silica Gel AL-N
Before
After

How it works. 

1

Ethylene outgassing

Fruits produce ethylene gas while ripening

2

Al₂O₃ & KMnO₄

Activated alumina granules act as carrier for potassium permanganate

3

Ethylene adsorption

Gaseous molecules penetrate the porous surface of the alumina granules

4

Oxidization

Ethylene chemically reacts with the potassium permanganate and gets neutralized

What`s left: 

​Ethylene is broken down completely and released into the air as CO₂

​The potassium permanganate irreversibly changes to manganese dioxide

The carrier alumina granules remain unaffected

Chemical reaction: 


3C₂H₄ + 12KMnO₄ 6CO₂ + 12MnO₂v + 12KOH

Activated alumina as carrier

Poresphere Aktiv-AL white granules

Normally used as a desiccant and adsorbent, it serves as a carrier material in this context. 

The granules are mechanically robust and chemically inert, staying in a solid form – not reacting with involved components themselves. With a surface area of nearly 300 m²/g, countless pores form on the spheres surface, to which potassium permanganate can adhere.

Color indicating when it´s time to change.


Purple: 

Fresh granules – ready to oxidize unwanted substances.


Brown

The potassium permanganate has fully reacted. The granules need to be changed. 

Poresphere Aktiv-AL K8 purple granules in petri dish
Poresphere Aktiv-AL K8 brown oxidized granules in petri dish
Poresphere Aktiv-AL K8 fresh purple and exhausted brown granules side by side in petri dish

Technical product information. 

Poresphere Aktiv-AL K8 fresh purple and exhausted brown granules side by side

PORESPHERE® Aktiv-AL K8

Activated alumina, impregnated with potassium permanganate

changes color when exhausted

adsorption of ethylene
removes odors
oxidizes pollutants
removal of chlorine and hydrogen sulfide


Composition: 60% Al₂O₃, 8% KMnO₄, 31% H₂O
Bulk density: 0,96 g/ml
Specific surface area: 280 m²/g
Pore volume: 0,4 ml/g


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Your achievements: 


Stable level of ripeness
Prevent a chain reaction before it starts. Without ethylene buildup, your goods will age much slower and not affect each other.

Lower complaint rate
Fruits will be protected against overripeness and mushy spots. You are able to supply high quality products. 

Predictable costs and logistics
A controlled ripening process helps ensure systematic planning throughout the entire supply chain, all the way to the end customer.

Request quote now.

Marco Kolbus

SALES & PRODUCT MANAGER

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mko@gf-dry.com

+49794694440111

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Luis Benz

MARKETING & SALES

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lb@gf-dry.com

+49794694440111

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FAQ – your questions, answered.

No, the granules are not reusable. The removal of ehtylene occurs through a chemical reaction (oxidation) in which the involved components are fully converted. The potassium permanganate irreversibly reacts to potassium dioxide. 

You can use our PORESPHERE® Aktiv-AL K8 for the removal of ethylene gases from food as long as the granules are safely packaged in satchets. These bags must comply with certain local guidelines and serve as a tear-resistant and waterproof protective barrier that is permeable only to air or gas.

Under no circumstances should potassium permanganate come into direct contact with food. Upon request, we will gladly provide you with required safety data sheets and conformity declarations. 

 

GIEBEL Desiccants GmbH
Carl-Zeiss Str. 5
74626 Bretzfeld 
Germany​

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