Analytical Report - Shellfish

Introduction

Shellfish do not make up a large proportion of the diet in the UK with an average per capita consumption of 14g per day. This does however mask large variations with some consumers eating 60g per day. The Food Standards Agency (FSA) has set a target of reduction in average adult salt consumption to 6g a day by 2010. Currently levels are around 10g for men and 7.6g for women. Most people therefore eat too much salt and there are significant health benefits from cutting intake particularly in terms of reducing the risks of hypertension, heart disease and stroke.

Some shellfish is sold in brine; water containing significant levels of salt acting as a preservative or flavour enhancer. Whilst the brine is not normally consumed, some of the salt can be transferred to the shellfish and consumed. Other shellfish may also have had salt added. Where salt has been added to pre-packed food this is indicated on the label in the ingredients list. However the amount of salt added does not have to be declared. Shellfish sold loose, for example at a fish mongers or an in-store fish counter is not required to provide an ingredients list.

The purpose of this sampling therefore was to determine the levels of salt across a range of shellfish. Forty two samples of Shellfish e.g. prawns, mussels, cockles, scallops were submitted for analysis by Kent Trading Standards.

 

Summary of results

The composition of all the samples was satisfactory, but there were labelling deficiencies on four products. One sample included brine, but did not declare a drained weight. A drained weight enables a consumer to identify the weight of actual shellfish in the container. The alternative would be for a Quantitative Ingredient Declaration to be given, that is the percentage of shellfish within the product. One product had been chilled in ice brine but this process was not declared in the name of the food.

Two samples had problems with the salt declaration. One had declared both sodium and salt but the figure for the salt calculated from sodium was incorrect. It is possible that this was a typographical error on the label print. Another sample had more salt than declared. It is difficult to assess from a single informal sample whether this is a one-off or a continuing problem across the whole batch. Further sampling and investigation would be required to make an assessment.

The salt content of the samples varied from 0.24g/100g to 3.39g/100g.  The highest result was on a sample of crayfish tails, cooked and peeled.  The pack size was 125g, and a typical portion size would be half a pack.  The salt would therefore amount to 2.1g per portion, or one third of the recommended daily allowance.  The average salt content for all the samples was 1.32g/100g, which for a similar portion size gives a salt intake of 0.8g or 14% of the RDA.  It is rare of course that these amounts of shellfish are eaten on a daily basis.  Using the UK National Diet and Nutrition Survey figures, it is likely that shellfish would account on average for only about 0.2g of salt per day.

The Food Standards Agency has worked with the food industry to set voluntary targets for the gradual reduction of salt in many staple foods. As such therefore canned tuna and salmon are included in these targets but there are no limits set for shellfish.

Consumers can select lower salt shellfish by checking any voluntary sodium or salt declarations in the nutrition panel. Increasingly some manufacturers are using the Food Standards Agency Front of Pack Signpost Labelling i.e. traffic light labelling. This enables consumers to at a glance see whether a product is high, medium or low in salt.

For more information on salt in the diet visit our Salt reduction page.

 

March 2008