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Monkfish: A Guide to Handling and Quality

07 September 2015

An Bord Iascaigh Mhara

The aim of this guide from the Irish Sea Fisheries Board (BIM) is to provide practical and contemporary guidelines on the handling and quality of monkfish, at all stages, from capture to the first point of sale.


Optimal handling and storage practices at sea and ashore are essential elements in the management of fish quality and the achievement of maximum return on national and international markets.

Defining fish quality, however, is not easy. The process includes the understanding and assessment of a range of factors, many of which depend on market preferences such as: species, size, capture method, seasonal condition and freshness.

Freshness, describes the degree of spoilage a fish has undergone since capture and is an important indicator for consumers. Very importantly, and unlike many other quality attributes, this is an area within the management of the catch, over which the fishing industry exerts significant control.

Sensory assessment remains the most popular method of assessing freshness. This type of assessment uses smell, texture and visual appearance to determine the quality of fish. It is a particularly useful technique as it is low cost and requires nothing other than careful and exact training. It is a widespread and reliable assessment method and provides the foundation for the design and application of this guide.

Lophius piscatorius

Angler/Monkfish – English
Láimhíneach – Irish
Rape – Spanish
Crapaud – French
Diabo-marinbo, Tambori – Portuguese
Z?abnica, Nawe?d – Polish

Lophius budegassa

Black-bellied Angler – English
Rape negro – Spanish
Tamboril-preto – Portuguese
Ditto – Polish

Lophius piscatorius / Lophius budegassa

The skin around the head and along the body bears fringed appendages resembling short fronds of seaweed. These structures, along with the ability of the monkfish to change body colour to that of its surroundings, allows the animal to blend into the background and hide in wait for its prey.

The monkfish has three long filaments sprouting from the middle of its head. The longest filament terminates in an expanded and irregular growth, which acts as a lure to attract prey species towards the mouth.

There are two separate species of monkfish caught by Irish vessels that are difficult to distinguish until they are gutted. Lophius piscatorius (whitebellied monkfish) has a white gut lining, whereas Lophius budegassa (black-bellied monkfish) has a black gut lining.

Certain markets prefer the black-bellied species as the flesh texture is considered to be superior. As a result this species commands a higher price in the fresh market than the white-bellied species. When frozen, however, there is no price differentiation between the species.

Excellent Quality

Excellent Quality Blood Vessels, Gills and Skin

Good Quality

Good Quality Blood Vessels, Gills and Skin

Poor Quality

Poor Quality Blood Vessels, Gills and Skin





Traditional Boxing & Icing

Traditional Boxing & Icing

Hygiene & Cleaning

In addition to correct handling, a high standard of hygiene and cleaning is essential to ensure production of a safe, high quality, seafood product.

    • After every haul, the deck, hopper, boxes, gutting area, knives, oilskins, aprons and all other equipment, should be washed down with seawater to remove fish blood, scales, offal, dirt and any other fouling substances.
    • At the end of every trip, the deck, fish hold, hoppers, boxes, gutting area, knives, oilskins, aprons and other equipment, should be washed down using a power hose and detergent to remove fish blood, scales, offal, dirt and any other fouling substances.

Washed down equipment using a power hose

    • A chlorine-based bleach should be used to thoroughly clean working areas and equipment, and inhibit any bacterial growth. To show the importance of this, sample swabs were taken from a hold of a boat where no bleach was used and from a hold of a boat where bleach was used. Under laboratory conditions bacterial growth was greater on the sample swab from the deck where no bleach was used. All residual bleach should be rinsed away with clean seawater.

Bacterial Growth with and without bleach

  • Detergents and sanitizing agents should be from the approved list issued by the Sea-Fisheries Protection Authority (SFPA) and should be used to the product specifications.

Tailing Onboard

Tailing exposes the flesh of fish to a higher risk of contamination compared to conventional onboard handling. Consequently your vessel must qualify as a factory vessel. The Sea Fisheries Protection Authority (SFPA) will check if the vessel has a Food Safety Management System (FSMS), which the crew are adequately trained to implement. The vessel will be assessed for layout and hygiene also.

These requirements are easily implemented on most whitefish vessels, with appropriate training and commitment from the skipper and crew. For vessels wishing to tail monkfish onboard, please refer to the BIM ‘User Friendly Guide to Tailing Monkfish for Spanish Markets’ (BIM User Friendly Guide Series, No. 3, 2007).

Tailing Onboard

September 2015

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