Protection of consumer rights, the prevention of fraudulent or deceptive practices, and the adulteration of food are important challenging issues facing the food industry. Consumers today are becoming increasingly interested in information regarding the origin of their food. Regulators are also demanding that food manufacturers confirm the authenticity and point of origin of their products and components. As a result, more stringent legislation reflecting these demands is now being imposed upon the global food supply.
Verifying the authenticity of foods can prevent
false description, substitution with cheaper
ingredients, adulteration, and incorrect origin
labeling. Food manufacturers are increasingly
aware of and are affected by reports of food adulteration.
Some adulterants are unknown and,
as such, are difficult to recognize using the targeted
screening methods typically used in food laboratories. Therefore, methods and solutions
for nontargeted screening of food samples are
urgently needed to provide proof of origin and
prevent deliberate or accidental, undeclared
admixture of foods. This article provides an
overview of food authentication challenges and
highlights the need for rapid development of
analytical methods to enable reliable authentication
of food.
Food authentication challenges
Consumers and producers place a high value
on accurate and defensible labeling. As a result,
manufacturers are taking proactive steps to provide
consumers with clear labeling, traceability,
and transparency. In doing so, producers must
manage a supply chain in which they source
ingredients from around the world and convert
them into a finished product that is then distributed
globally. Food producers, therefore, not
only face the challenge of complying with international,
national, and local traceability rules,
but the challenge of maintaining responsibility
for the authenticity of ingredients.
The growing variety and complexity of available
foods also poses a challenge within the food
industry. Consumers are demanding information
about and proof of the quality and safety of
“new” food items and preservatives that prevent
deterioration. Meanwhile, rapid population
growth has resulted in shortages of raw materials,
which in turn has forced some producers to
“bulk up” their products with questionable fillers,
thus introducing additional ingredients of
unknown origin.
Regulatory framework
Regulators around the world have been tasked
with developing standards and legal policies to
determine ways to identify and label food using
appropriate terminology. Regulatory agencies
now require food testing laboratories to meet
higher standards of detection and analysis. They are also requiring laboratories to have the capacity to detect extremely low concentrations of potential contaminants. In addition, new and unknown
compounds and matrices are continually being
added to food, necessitating the requirement
for both targeted and nontargeted analysis. In
order to prevent excessive levels of contaminants
from entering the food chain, but it is also vital
that food laboratories are equipped with robust
instrumentation that can meet not only today’s
threats but that is also advanced enough to
address tomorrow’s challenges.
European controls on food labeling were introduced
with Directive 79/112 of the European
Parliament in 1979, and additional controls
and amendments have since been added, creating
an array of labeling requirements. In 2000,
the original 1979 directive and its amendments
were consolidated into a single new directive,
The Council Directive 2000/13/EC of The
European Parliament and of the Council of
20 March 2001,1 which focuses on preventing
fraudulent or deceptive practices and adulteration
of food that may mislead consumers.
Directive 2000/13/EC requires detailed food
labeling to include the exact nature and characteristics
of a product, enabling an informed
consumer choice. It also requires that the ingredients
list include all raw materials in descending
order by weight, using their specific name.
European law also provides labeling for protected
designation of origin (PDO), protected
geographical indication (PGI), and traditional
specialty guaranteed (TSG) to ensure the
authenticity of regional foods and specialties.
These laws, enforced within the EU, ensure
that only products genuinely originating in
that region are allowed to be sold as such,
eliminating unfair competition and misleading
products that may be of inferior quality or of
different components.
Techniques
Figure 1 - Techniques used to test food authenticity.
Table 1 - Food authenticity testing techniques
Reliable analytical tools must be available along
the food chain to verify the nature of food. Typically,
the selection of techniques is driven by several
factors, including method detection limits, sample
preparation, cost, and throughput. Such tools
should permit rapid, nondestructive, and inexpensive
analysis. There are a variety of techniques to
test food authenticity, including methods based on ultraviolet (UV), near-infrared (NIR), midinfrared
(MIR), and Raman spectroscopy (see Figure 1 and
Table 1). All of these are routinely used to control
both raw materials and finished food products for
specific production standards.
When monitoring for multiple chemical contaminants
in food, it is common to test a variety of matrices that require multiple sample preparation
techniques. Issues must be addressed,
however, including the costs of purchasing and
running the analytical instruments as well as
the specificity of the measurements.
Food safety analysts are also turning to mass spectrometry instruments and software to run
multiresidue analytical methods. Stable isotope
ratio mass spectrometry (SIRMS) is most
often used to assess sample origin by looking
for the changes in the characteristic isotopic
profiles of stable isotopes of common elements
such as hydrogen, oxygen, carbon, and nitrogen.
SIRMS provides high-quality selectivity
and achieves very low detection limits, even in
complex food samples.
Chromatography is being increasingly
employed in food science and technology
because of its high separation capacity. Chromatographic
techniques exist for rapid, reliable
separation of molecules with extremely
similar chemical characteristics even in complex
matrices. Gas chromatography is most
frequently used for the quantitative analysis
of numerous molecules such as normal constituents
of foods, legal or illegal additives,
and pollutants.
There is room for development in the area
of evaluation and processing to speed data
analysis of large food sample batches screened
for hundreds of compounds. The development
and evaluation of software tools that
permit screening for the presence of unknown
contaminants is crucial for easy identification
and confirmation. This process is complicated,
however, due to the complexity of
food samples. Since a typical food extract can
contain thousands of compounds in a broad
range of concentrations, software tools must
differentiate between “normal” and contaminated
samples, even at low concentration.