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polyvinyl acetate. A group of peaks identified as branched chained carbox-
ylic acids of quite high molecular mass (approximately 10 carbon atoms per
molecule) can also be identified in the pyrogram. This pyrogram is typical
of a vinyl acetate/vinyl versatate copolymer. Vinyl versatate is also known as
VeoVa and this type of paint is also known as a VA/VeoVa copolymer. Such
paints have been and are used as both internal and external decorative wall
paints. The pyrogram was compared to a sample of green paint from the
monument and was found to be of the same components.

8.6 Food and Fragrance Analysis

8.6.1 Introduction to Food and Fragrance Analysis
Intellectual property (IP) crime is the counterfeiting of trade and copyrighted
goods and services. High-value items are open to adulteration; this includes
food substances, alcoholic beverages and fragrances.

8.6.2 Food Fraud

Food fraud is the deliberate modification of a product or labelling for the
intention of deceiving the consumer. The Food Standards Agency 4 states that
the two main types of food fraud are 'the sale of food that is unfit and poten-
tially harmful' and the 'deliberate misdescription of food'. The first type of
food fraud covers the sale of goods at or past their sell-by dates; the second
describes the mislabelling of food stuffs (e.g., if apples are labelled as being
'organic' but they have not been grown on an organic farm).
Food substances such as olive oil, honey, saffron, milk, fruit juices, and
coffee are amongst the most commonly adulterated food products. 5 For
example, extra virgin olive oil is one of these high-cost food products that is
open to adulteration; often, other cheaper oils, such as hazelnut, sunflower
and vegetable oils, are added to the extra virgin olive oil. In this type of adul-
teration, the final product is cheaper to manufacture but allows sellers to
charge the full price of extra virgin oil (when in fact they are selling a cheaper
imitation). Extra virgin olive oil can be analysed using SPME-GC-MS. This
is an analytical method that is used to examine the flavour compounds since
it has previously been difficult to differentiate between olive oil and other
oils due to the similarity of the oils in the composition of fatty acids, triacyl-
glycerols and sterols. SPME (see Section 7.2.3) allows sampling of the volatile
compounds present in the headspace of a vial. Only the volatile compounds
that enter the headspace will be analysed by this method and this has proven
a good analytical technique for establishing differences between olive oil and
other oils (see the Further Reading section for more information).