Revision to codes of practice in commercial langoustine industry – improving yields, quality and sustainability
Submitting Institution
University of GlasgowUnit of Assessment
Biological SciencesSummary Impact Type
EnvironmentalResearch Subject Area(s)
Agricultural and Veterinary Sciences: Fisheries Sciences
Medical and Health Sciences: Clinical Sciences
Summary of the impact
The UK fishing industry for Nephrops norvegius (Norway lobster or
Scottish langoustine) is estimated to be worth £100 million annually.
Caught animals are either maintained for live transport to Europe or
frozen for use in food products; however, survival rates and meat quality
were poor, respectively. University of Glasgow research has provided key
insights into the basic biology and survival of Nephrops after
capture and driven pioneering reform of the codes of practice of two major
UK seafood companies. This reform has directly resulted in improved yields
and quality, and led to a Scottish fishery being the first in the UK to be
granted an internationally recognised sustainability accreditation.
Underpinning research
The University of Glasgow Langoustine Lab offers support to the fisheries
and seafood industries that exploits over 25 years of research expertise
in the population biology and health status of Nephrops. Working
under the direction of animal physiologist Professor Douglas Neil, the
Langoustine Lab has collaborated with colleagues at the University Marine
Biological Station Millport (UMBSM), University of London and the Centre
for Environment, Fisheries & Aquaculture Science (CEFAS) to
investigate (i) the recovery potential of Nephrops destined for
the live transport market in association with Scotprime Seafoods Ltd and
(ii) the post-capture handling of tail meat for the raw product market
with Young's Seafood Ltd.
Recovery potential of product destined for the live transport
market
Research by the University of Glasgow led team conducted in the mid-2000s
compared stress-related metabolic parameters in creel (lobster pot)-caught
and trawl-caught Nephrops. Two established indicators of stress
within skeletal muscle were quantified: i) the adenylate energy charge
(AEC) ratio, which describes the balance of energy sources ATP, ADP and
AMP within biological cells and ii) the pH level. Significantly lower AEC
ratios and pH values were observed in trawl-caught than in creel-caught
animals,1,2 indicating rapid development of extensive muscle
stress with a switch to anaerobic metabolism (i.e. without oxygen) while
the animals struggled to escape from the net. In addition, trawl-caught
animals exhibited significantly greater physical damage than did
creel-caught specimens.3 Due to the labour intensiveness of
creel-capture methods, Scotprime Seafoods Ltd were routinely employing the
trawl-capture process to meet the market demands for Nephrops.
Commonly, the first catches of the day were reserved for meat products
whilst the later catches were maintained on deck in air for the live
transport market as these animals were perceived to be the strongest. A
follow-on study by the team rapidly placed freshly trawl-caught animals
into on-board tanks with continuously circulating seawater and measured
stress parameters at varying times post-submersion.4 These
experiments showed that the AEC ratio returned to pre-submersion levels
within 4-6 hours, showing for the first time that Nephrops can
recover from the extreme metabolic stress of trawl capture. Crucially,
measurements taken after the animals had been transferred to local
on-shore tanks for 24 hours indicated that recovery was maintained after
capture, thus confirming the metabolic stabilisation of the animals.
Post-harvest handling of tail meat destined for the raw product
market
Parallel research on early post-mortem Nephrops characterised
product deterioration and spoilage between capture and the onset of ice
storage. In two papers published in 2011, the University of Glasgow led
team quantified microbial spoilage in tail meat from fresh carcasses over
a range of delay times (0, 4, 8 and 24 hours) at a holding temperature of
16oC (the mean air temperature during the Nephrops
fishing season).5,6 Measurements were taken over the subsequent
week of ice storage to quantify relative deterioration; findings at each
time-point were correlated with meat quality data obtained from an expert
trained panel from the Food Innovation Institute (Roslin, UK), a
commercial enterprise providing consultancy services to the UK food and
drink industry. Tail meat that was frozen after 4 hours rather than
immediately following capture showed no significant detriment to quality 5
days after freezing. By contrast, meat that was kept at 16oC
for more than 4 hours after capture showed substantial biochemical
degradation and increased bacterial load, making it unpalatable.
Bycatch composition
Due to the small mesh size of the nets used for trawl-capture of Nephrops,
bycatch of at-risk species (such as doc haddock rays) is a significant
issue. At 2-month intervals over an 18-month period (2009/2010), the
research team measured and recorded the details of the entire catch of a
Young's Seafood Stornoway fisheries vessel, yielding a highly focussed and
geographically mapped inventory for monitoring bycatch composition. These
data were then logged into the `YoungsTrace' system (an existing on-board
GPS system to monitor the position of the vessel when trawling). Further
amendments to this resulted in the adaptation of the `YoungsTrace' system
into a validated self-assessment system which the skippers could routinely
use to monitor bycatch.SE reports (i)&(ii)
Key University of Glasgow researchers: Douglas Neil (Senior
Lecturer [1975-2006]; Professor of Animal Physiology [2007-2011]; honorary
staff [2011-present]); Graham Coombs (Professor of Biochemical
Parasitology [1974-2006]; moved to University of Strathclyde in 2007);
Amaya Albalat (Postdoctoral Research Assistant [2005-2010]); Simon
Sinclair & Sebastian Gornik (Research Assistants [2005-2010] and
[2004-2007] respectively). External collaborators: Jim Atkinson
(Professor of Marine Biology, UMBSM) and Grant Stentiford (Director,
Crustacean Disease, CEFAS, Weymouth)
References to the research
Grants: The research above was supported by over £1 million
from the European Union (EU) Financial Instrument for Fisheries Guidance
(now the European Fisheries Fund) schemes. These grants have resulted in a
series of reports, which were returned to the Scottish Executive
including:
(i) Neil DM et al. The
Scottish Nephrops Survey Phase II. A joint venture to generate
high quality Nephrops products from a sustainable fishery
(2008)
(ii) Milligan R & Neil DM. The
Scottish Nephrops Survey Phase III. Evaluation of measures for
reducing bycatch and discards in a Nephrops fishery (2013)
Details of the impact
The Nephrops fishing industry
Once considered part of the cod `bycatch' (that is, caught
unintentionally), Nephrops have become increasingly popular among
consumers over the past 50 years. Nephrops are delivered to the
food chain as either live animals or raw meat for subsequent freezing or
cooking. The increased demand for Nephrops has led to the use of
mass-fishing methods such as trawl-capture using nets, which is largely
unregulated within the commercial industry. Boats commonly collect
sequential trawl catches over an 18-hour day with little standardisation
of methods and frequently no understanding of Nephrops biology or
the damage exerted by capture methods.
Scotprime Seafoods Ltd.
Lack of understanding of the consequences of trawl-capture were
highlighted when one of the major UK commercial seafood exporters, Scotprime
Seafoods Ltd attempted to branch into the lucrative live Nephrops
market.a This company found wide variations in the survival
rates at destination of the Nephrops exported by live "vivier"
transport to continental Europe. The company partnered up with University
of Glasgow whose research showed that the animals caught later in the day
were in fact exhausted and near physiological collapse from the trawl
methods used but crucially that the potential existed to allow them to
recover by resting in seawater tanks. As a direct result of these
findings, recommendations were made to Scotprime Seafoods Ltd to reform
their post-capture handling and transport working practices.
"[The] benefits of collaboration between our company and the
University of Glasgow have been numerous and diverse. [The] results of
trials at sea have shown the need to physically alter the set-up of
catching vessels in order to make them more successful at capturing and
maintaining live Nephrops. To date approximately 15 vessels have
invested in this way and have boosted their income as a result. This is
ongoing with the latest being completed in April 2013."...General
Manager, Scotprime Seafoods Ltd.a
Following the installation of the on-board recovery tanks on boats in the
Scotprime Seafoods Ltd fishing fleet, the first catch of the day, instead
of the last, is now placed to recover for the remainder of the day.
Following a short transport (<1 hour) to an on-shore facility, animals
are placed into recovery tanks overnight for further physiological
stabilisation prior to transport to market. University of Glasgow research
also revealed that there is a minimum time which animals should be kept in
the holding facility before onward shipping to customers. This allows
animals the best chance to recover to pre-capture physiological state and
affords them the greatest chance of arrival in good condition. The
University of Glasgow research also showed that it was possible to relate
the physiological status of Nephrops to visual cues in the
behaviour of the animals. This finding allowed the development of a
"Vigour Index"; training staff to spot these cues has allowed animals to
be graded more efficiently and with a greater degree of accuracy. Since
2008, this practice has been used by all Scotprime Seafoods Ltd staff and
all new staff are trained in its use.a
These improvements in handling at source saw survival rates at
destination of Nephrops following transport increase, with marked
improvements in product quality (as reported by customers) leading to
uniformity in supply. Production at Scotprime Seafoods Ltd prior to
University of Glasgow involvement was on average 65 tonnes per year; this
value has since risen to 100 tonnes (years 2008-2012).a This
has reflected an increase in live department profits by a similar
percentage increase and the live animal handling department now employs an
additional two members of staff in response to increased production.a
Young's Seafood Ltd.
Young's Seafood Ltd has a 55% share of the UK Nephrops market and
is the leading brand for frozen fish, which includes a breaded scampi
range. The raw Nephrops tail product —predominantly sourced from
the company's Stornoway fishery — is highly susceptible to post-mortem
spoilage, and wastage levels in the company were high owing to poor
handling practices. In an attempt to reduce wastage and improve product
quality, the University of Glasgow Langoustine Lab demonstrated that
deterioration of Nephrops meat depends on initial storage
temperature. In 2006, the researchers recommended a `handling window' to
Young's in which the raw product must be sorted, tailed and iced within
less than 4 hours of capture. Prior to this recommendation, many of the
boats in the Young's fishing fleet did not even carry ice and the product
was only iced at port or within the processing facility. Data obtained
from Young's confirm the successful implementation of the `handling
window' showing that the mean on-board storage temperature has reduced
from 5.6oC in 2006 to a steady 2.5oC in 2012.b
A spokesman from the company states:
"Professor Neil's work clearly established the benefit of icing the
freshly caught product as soon as possible after landing which saw an
improvement in the quality of the product being landed. This brought
with it several benefits. One, the fishermen had less product rejected
for poor quality therefore providing a more stable income for their
efforts and secondly there was a gain in processing yields as the
product had deteriorated less prior to processing and so there was less
wastage through rejects and quality of the meat being produced improved
as it remained firmer."
Improving sustainability
In 2009, Young's Stornoway fisheries successfully attained the Marine
Stewardship Council (MSC) certification of sustainable good practice.c
The MSC is a world-recognised, international body that aims to improve
practices of the seafood industry and promote sustainable fishing of
existing stocks. This was the UK's first award for a trawl fishery and the
University of Glasgow's input was instrumental in its successful
recognition. Assessment, certification and annual surveillance audits on
the Stornoway Nephrops fishery have since been conducted by the
independent assessors Moody Marine Ltd.; the University of Glasgow studies
are cited throughout the annual reports clearly demonstrating their
influence on the maintenance of the MSC certification. The `YoungsTrace'
self-assessment system was implemented across the Stornoway fleet in 2010
contributing to the maintenance of the certification.d The MSC
certification had a positive impact on Young's ability to expand their
customer-base.
"Attaining the MSC certification allowed Young's to attract business
from other UK markets for scampi and European markets for langoustine
for MSC designated products." and "there is no doubt that certain
European customers would not have purchased product from us without the
MSC certification [it] was of primary importance to them"...General
manager, Young's Seafoodb
Sources to corroborate the impact
a. Statement from Scotprime Seafoods Ltd. (available on request)
b. Statement from General Manager, Young's Seafood Ltd. (available on
request)
c. Public
announcement of MSC accreditation gained by the Young's Seafood Ltd
Stornoway Nephrops Fishery, 2009
d. Assessment, certification and annual Surveillance audits on Stornoway
Nephrops Fishery by the independent assessors (Moody Marine Ltd.)
which cite the University of Glasgow/UMBSM research throughout: