A major challenge in aquaculture and wild-caught sectors is to ensure that Shrimp, Prawn and other Crustaceans caught fresh should retain their full market value.
NatuFresh is a versatile solution to maintain the freshness of Shrimp, Prawn and other Crustaceans after the catch.
Shrimp and Prawn are important aquatic species for use in aquaculture and for their catches worldwide for human consumption. The quality and shelf life of shrimp/prawn freshly harvested from different ponds/farms or catches from seas/rivers are usually stored on ice and then freezed. To quantify the quality and shelf life is difficult to assess the untreated shrimp.
Shrimps are considered perishable due to easy loss of freshness during - exposure to the air, storage and distribution, especially when transported with the viscera intact. Various enzymatic and bacterial activities occur in the shrimp during air exposure, storage and distribution, leading to spoilage accompanied by the production of unpleasant odour, discolouration and chemical changes in the meat (Du et al. 2015; Ginson et al. 2013).
The production of unpleasant odours, the occurrence of black-spots and meat softening are principal sensory and biochemical Quality Index features due to their close correlations with the decrease in freshness (Du et al. 2015). An unpleasant odour is known to be caused by Aldehydes, Ketones, Trimethylamine, Ammonia and volatile Sulfur compounds produced by the degradation of lipids and proteins by microorganisms (Ocaño-Higuera et al. 2011; Tsironi et al. 2009; Du et al. 2015; Jaffrès et al. 2011). The decomposition and softening of meat due to a rapid freshness drop is a result of protein degradation caused by microorganisms (Dai et al. 2016).
Shrimp freshness is directly related to the value of a commodity and thus it is crucial to evaluate it promptly. Sensory evaluation is the most important method for determining the freshness and quality of aquatic products (SantAna et al. 2011; Cardenas Bonilla et al. 2007; Alasalvar et al. 2001).
However, the disadvantage of sensory evaluation is its lack of objectiveness. Therefore, chemical methods based on scientific procedures have been used coupled with a sensory method as an effective multimodal way of quality evaluation (such as total volatile basic nitrogen (TVB-N), trimethylamine (TMA), volatile sulphur compounds, histamine etc.).
Melanosis or Black-spot Development
Melanosis, also known as black-spot, is the development of black pigments on the exoskeletons of crustacean's postmortem (Montero et al. 2004). Black-spot is caused by a system of enzymes that are naturally present in the shrimp. These enzymes, in the presence of air, can chemically transform colourless compounds in the shrimp into complex brown pigments near the shrimp surfaces and shell.
Black-spots occur mostly due to discolouration, which is a defect caused by the activity of Tyrosinase during storage (Mu et al. 2012; Tsironi et al. 2009). Tyrosinase is a copper-containing enzyme present in plant and animal tissues that catalyses the production of melanin and other pigments from tyrosine by oxidation. It is found inside melanosomes which are synthesized in the skin melanocytes.
On shrimp, black-spots typically begin on the cephalothorax and caudal tip of the tail, before spreading to the rest of the shell. Melanosis is a major issue in the marketability of the product with the consumer.
10% of a harvest is generally discarded due to Melanosis or Black-Spot. The onset of melanosis or Black-spot has traditionally been treated by different methods and also with sodium metabisulphite. However, doing so only hides melanosis by bleaching it out rather than curing the problem. The product has also been known to cause allergic reactions.
The use of melanosis or browning inhibitors in Shrimp and Prawn is restricted by considerations relevant to toxicity, wholesomeness and effect on taste, flavour, texture and cost. Melanosis inhibitors may be classified in accordance with their primary mode of action.
NatuFresh is a Food Grade formulation with 1,3-Dihydroxy-4-Hexylbenzene which effectively avoids the development of melanosis/black-spot and helps to retain the original colour and texture of the catch for extended periods.
- NatuFresh liquid is a product free from sulphites, specially designed to preserve and inhibit melanosis in all species of crustaceans.
- NatuFresh can be used immediately after harvest at the ponds or after capture, onboard or on land.
- Treatment is easy to apply and yields desirable results quickly.
- It does not change any characteristics, maintaining the original colour and texture for longer periods of time.
- Reduces difficulty of peeling.
- "Non-toxic", "sulphite-free" and "allergen" statements are not required on the lable.
- Non-corrosive to machinery resulting in reduced costs whilst safe for workers to use.
- Suitable for fresh, frozen or frozen / thawed products.
- Extends shelf life.
NatuFresh - Proven with Multiple Species
- A proven 'sulphite-free' 'anti-melanosis' solution for all Penaeid shrimp species and other crustaceans.
- Currently being used worldwide on Shrimp Farms, Fishing vessels, Processing Factories and with excellent results.
Usage Instructions
- One Litre NatuFresh is to be mixed with 1000 liters of water which will treat 2 tons of Shrimp/Prawn/other Crustaceans.
- Clean harvest bins are to be used. The dip water temperature should be maintained ideally between 1 - 5 degrees Celsius throughout the process.
- NatuFresh will function in both Seawater solution and Fresh water solution.
- NatuFresh should be shaken before the application and stirred vigorously when poured into a bin containing Ice/water during the preparation of the dipping solution.
- DO NOT mix with any acid-based product or in conjunction with Sodium Metabisulphite.
- Shrimp/Prawn /other Crustaceans should be soaked in the solution for a minimum of 5 minutes to ensure effective coverage and transported in the harvest bin to the plant.
- When treatment of the recommended number of boxes have been completed in the dipping tank, the solution must be discarded and again fresh dipping solution is to be prepared for further use.
Presentation
1.0 litre.