Why choosing the right prawn solution to stop Blackspot matters

By Fintan McConnell, Product Manager Food Ingredients.

A common challenge for fishermen and seafood processors that work with prawns as well as other crustaceans is Blackspot. Otherwise known as melanosis. It is caused by a naturally occurring enzyme, that starts as soon as the prawns and crustacean are harvested from the water. Blackspotting primarily appears on the head, tail, as well as the swimmerets (crustacean abdominal limbs and appendages). Most consumers consider its appearance off putting even though it is harmless and does not alter the quality of the product. To combat this, traditionally the industry has turned to using sodium metabisulphite, which is effective but does have negative side effects.

Sodium metabisulphite is effective but there are alternatives

Though sodium metabisulphite achieves results, it does have issues that include causing allergic reactions in some consumers. Added to that it can also irritate the eyes and noses of workers. Additionally, when used with water it can produce sulphur dioxide gas which is dangerous especially in small confined spaces such as a ship’s hold. Lastly, it’s corrosive properties have been known to damage equipment.

Fortunately, there is an alternative to sodium metabisulphite, products that use 4-hexylresorcinal as a base. An organic compound, 4-hexylresorcinal has local anaesthetic as well as antiseptic properties. Most importantly it does not have side effects and in fact is commonly used in products such as throat lozenges and skin care products.

There are a few different 4-hexylresorcinal products on the market. As a result it can be difficult for fishermen and seafood producers to know which is the most suitable. Following an extensive evaluation process here at NCC Food Ingredients we decided on recommending to our customers Crustaxyl from PH7.   

Why you should use Crustaxyl instead

The key reasons why we recommend Crustaxyl is that fundamentally it is better value than other products on the market that do not contain sodium metabisulphite. It also maintains the original colour and texture for up to 11 days refrigerated and 24 months frozen. This is longer than most other solutions, added to that it provides the raw material with an intense brightness. Maintaining the intensity of the eyeball as well as strengthening the soft part of the crustacean. Meaning that your catch looks and tastes as fresh as when they were caught. If you would like to know more about Crustaxyl click the button below to read the sheet:

We also provide an excellent reduced sulphite solution called Q20. This product stops blackspotting effectively, retaining the prawns ‘just caught’ appearance. It also improves the shelf-life for longer periods of time than only sodium metabisulphite. Added to that, it doesn’t modify the taste characteristics and it can be used with all types of crustaceans: Langoustines, Shrimp, Prawn, Lobster, Crab, Crawfish, etc.

NCC Food Ingredients has years of experience in the seafood and fish industry. We also provide fish products such as moisture retainers, whiteners, and texturisers. To find out more fill out the form below and we’ll be in contact.

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