Chemical Analysis

FOOD ANALYSIS

J.S. Hamilton Poland SA is a unique worldwide company that comprehensively combines inspection, testing and consulting services with analytical research performed in our own laboratories.

Every day hundreds of different analysis are provided in different J.S. Hamilton Poland SA laboratories to identify food safety threats and its quality in terms of microbiological, organoleptic and physicochemical parameters. Analytical testing services are the main part of our company for various branches of food industry.

PHYSICOCHEMICAL TESTING

Physicochemical testing is complementary to the information gathered by microbiological analysis or sensory and organoleptic testing. Such testing enables gathering the necessary information on product’s ingredients (such as protein, fat, water, fiber, salt or ash), a presence of micro- and macroelements, vitamins and contaminants (such as heavy metals, pesticides, polycyclic aromatic hydrocarbons or dioxins) or food additives.

J.S. Hamilton Poland SA laboratories offer a wide range of services that, in its broadest approach, meets the customers’ expectations in terms of food safety and food quality.

CONTAMINANTS AND RESIDUES ANALYSIS

Consumer protection and stability of the market are the goal of European Union’s policy in terms of food safety. Every product available on the market should comply with European food law and certain standards set in specifications, both concerning basic parameters and substances harmful for the customers’ health and lives, the amount of which should not exceed its legal levels. Due to modern and progressive agricultural and food industry, it is necessary to monitor the residues of contaminants in food and feed products.

Testing for contaminants requires the cooperation between the Client and the laboratory. Such collaboration helps to identify the threats, set the goals of a certain analysis and assert the appropriate research method.

The main causes of contaminations concerning food safety are residues of antibiotics, chemotherapeutics, pesticides, dioxins, polychlorinated biphenyls, mycotoxins, polycyclic aromatic hydrocarbons, acrylamide, 3-monochloropropano-1,2-diol, nitrates, melamine, heavy metals and toxins of vegetable origin.

RESIDUES OF VETERINARY DRUGS

Antibiotics and chemotherapeutics are substances commonly used for various human and animal diseases. The invention and using of these substances is considered as the greatest medical achievement of the XX century.

However, these substances, if present in muscles, animal offal or products of animal origin (such milk, eggs, honey), may become a potential source of negative impact on consumers’ health. Facing most such cases is caused by a failure to comply with certain grace periods, dosage of veterinary drugs incompatible with indications, against the recommended use or applying them to wrong animal species.

In order to protect the health of consumers in the European Union countries, a number of restrictions and regulations have been introduced to clarify the use of antibiotics and chemotherapeutics on food-producing animals.

Monitoring the presence of residues of veterinary drugs is a complex and difficult issue due to the fact that these agents belong to different groups (which is related to differences in the chemical structure of individual compounds) and that metabolism strongly influences the presence of residues in the final product. For testing of veterinary substances residue is used either the microbiological screening methods that relatively quickly allow for assessment the raw material or the latest analytical techniques (liquid chromatography and gas chromatography coupled with tandem mass spectrometry) are used in the residue tests which, in a relatively fast way, allow the batch of raw material to be evaluated.

J.S. Hamilton Poland SA laboratory in Gdynia develops and validates further analytical methods allowing to offer wide range of compounds in different foodstuffs, taking into account the stricter regulations for lowering the maximum residue limits in different types of matrixes. Most of the methods have also been validated in the lowest possible level of residues, so they can be used to monitor products “free” from veterinary drugs.

PESTICIDES RESIDUES

The use of pesticides in agriculture has led to a significant increase in crop yields and has reduced the incidence of diseases among farm animals and thus increased production of food. Furthermore, the presence of pesticide residues in the final product is highly undesirable because of their proven negative effects on human organisms (teratogenic, mutagenic and carcinogenic effect). For this reason, it is important to continuously monitor pesticide residues (and pesticide transformation products) in food.

Due to the presence of pesticide residues in foodstuffs at low levels, it is necessary to use appropriate techniques for the isolation and concentration of analytes from the matrix for their accurate determination. The diversity of matrices and compounds belonging to the pesticide group makes it very difficult to find an universal method for determination all pesticides in food products. Therefore, it is necessary to find a compromise between the number of compounds to be determined, their levels of detection and time and work-consuming and the complexity of the analytical instrument used to carry out testing in food and feed.

J.S. Hamilton Poland SA laboratory in Gdynia has been monitoring the presence of pesticide residues for many years, continuously improving analytical methods and expanding the scope of tested pesticides. The Laboratory offers a number of methods for the determination of pesticides residues, characterized by varying degrees of complexity, for different groups of analytes and for various compounds.

DIOXINS AND POLYCHLORINATED BIPHENYLS

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), called dioxins – it is a group of more than 200 chemical compounds (congeners) of similar chemical structure, whose molecules differ in position and number of chlorine atoms and exhibit a similar mechanism of toxicity to living organisms. According to a number of studies, polychlorinated biphenyls (PCBs) also indicate a similar toxic mechanism. 17 dioxin congeners containing 4 to 8 chlorine atoms are especially harmful for human health. Extremely toxic compounds among PCDDs and PCDFs are those, in which the chlorine atoms are at positions 2,3,7 and 8, e.g. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

Individual congeners of dioxins and polychlorinated biphenyls may exhibit different toxicities for human and animal organisms, so the appropriate conversion factors, known as toxic factors, are used for the expression of results. The use of toxic equivalency factors (TEF) make it possible to express the sum of the toxicity of congeners and facilitate the risk assessment. The results of the determinations are therefore expressed in terms of the sum of all dioxins and congeners of dioxin-like polychlorinated biphenyls as toxic equivalents (TEQ), which are the sum of the multiplication of the content of individual congeners and their toxic equivalency factors. The TEF value indicates how many times the toxicity of a compound for a human being is less than the most toxic congener 2,3,7,8-TCDD with TEF =1.

MYCOTOXINS

Mycotoxins are toxic secondary metabolite produced by organisms of the fungus kingdom, mainly Aspergillus, Penicilium and Fusarium. Factors affecting the production of mycotoxins include fungal strain, substrate type, humidity and temperature, water content in the product and its degree of ripeness.

Mycotoxins can cause a number of diseases. They are toxic when ingested in large quantities, but also long-term exposure to small doses may pose a health risk. Apart from health risks, mycotoxins can cause huge economic losses.

There are more than 300 mycotoxins identified, including aflatoxins and trichothecenes (deoxynivalienol, T-2 toxin, HT-2 toxin and nivalenol), zearalenone, fumonisins, ochratoxin A, patulin and ergot alkaloids.

Already in the early 1960’s, just after poultry epidemic in England, J.S. Hamilton Poland SA in Gdynia was interested in the research determining the content of mycotoxins. Analytical activity – continued over the years – is currently based on the use of chromatographic techniques – liquid chromatography with fluorimetric detection or liquid chromatography coupled with tandem mass spectrometry.

POLYCYCLIC AROMATIC HYDROCARBONS

Polycyclic aromatic hydrocarbons are polycyclic hydrocarbons containing condensed aromatic rings. They are formed during the combustion process (burning of wood, smoking of cigarettes or producing of asphalt). They can appear in food due to heat treatment (frying, smoking and grilling) or due to environmental pollution.

Their presence in food is undesirable because many of them are suspected or are proven genotoxic, mutagenic and carcinogenic properties. The monitoring of PAHs in food has been the subject of interest of producers for many years. J.S. Hamilton Poland SA laboratories have an appropriate analytical methodology which detects PAHs in many types of foodstuffs, concerning different maximum levels.

HEAVY METALS

Heavy metals are an example of contaminants that migrate into food mainly from the environmental surroundings. According to the available literature, plants and products of plant origin such as bread, cereals products and also fish and seafood are the most exposed to heavy metals contamination.

The most commonly found in food, and the most dangerous heavy elements are cadmium, lead, mercury and arsenic. Prolonged exposure to high levels of these elements may increase the risk of developing cancer and nervous system disorders, as well as impaired of immune function.

The monitoring heavy metals is realized in J.S. Hamilton Poland SA in Gdynia using properly developed research methods – based on Polish and international standards as well as own research procedures. The cutting-edge devices – mineralizers, inductively coupled plasma optical emission spectrometers and inductively coupled plasma mass spectrometers are used for analysis.

DETERMINATION OF NUTRITION VALUES

The issue of informing consumers about the nutritional value of products is governed by applicable law. Correct labeling of food products, complying with requirements of food law, is therefore an indispensable element of ensuring the safety of food available on the market.

The label should indicate the energy value of the product and the amount of fat, of which saturated fatty acids, carbohydrates, of which sugars, proteins and salt. If no salt ingredient has been used in the technological process, a note that the salt content is due solely to the presence of naturally occurring sodium in the product may be placed directly near the nutrition declaration.

The content of mandatory nutrition information can be enriched with information on the amount of monounsaturated fatty acids, polyunsaturated fatty acids, polyols, starch, fiber, vitamins and minerals. This is a closed list so it is not possible to supplement it with any additional nutrition information, for instance, individual polyunsaturated fatty acids.

Nutrition information should be given in grams per 100 grams or 100 milliliters. In addition, they can be expressed per portion or unit amount of food.

The content of each nutrient in a foodstuffs is determined by giving average values based on:

laboratory analysis of food products,
calculation based on known and actual average values of the components used,
calculation based on generally accepted data.

The producer can use appropriate laboratory tests (recommended for processed and compound foodstuffs) or make appropriate mathematical calculations based on recipe, using knowledge of process technology. In both cases, adequate product knowledge is necessary to include all components of the product.

VITAMINS

Vitamins are an essential elements for the proper functioning of organisms. The level of vitamins is therefore one of the most important indicators of the quality of food products and the appropriate technological processes.

Vitamins can be of natural origin or synthetically produced, and their determination is extremely complex due to the variety of structures and properties.

Depending on the classification and structure of vitamins, different analytical methods are used. Chromatographic techniques (liquid chromatography with fluorescence or spectrophotometry detection) or microbiological techniques are most commonly used. Less commonly used techniques are enzymatic or titration methods.

Vitamins (shown in the table in Appendix XIII of Regulation 1169/2011) can be declared on the food label if they are in significant quantities. This significant amount is calculated using the appropriate relationships:

15% of the reference intake, included in 100 g or 100 ml, for non-beverage products;
7,5% of the reference intake, contained in 100 ml, for beverages;
15% of the reference intake, per portion, if the package contains only one serving.

FOOD ADDITIVES

The idea of using of food additives is improvement of food taste and it appearance, increase the stability of the food and facilitate the technological process.

The European Union legislation defines additives as “any substance not normally consumed as a food in itself and not normally used as a characteristic ingredient of food, whether or not it has nutritive value, the intentional addition of which to food for a technological purpose in the manufacture, processing, preparation, treatment, packaging, transport or storage of such food results, or may be reasonably expected to result, in it or its by-products becoming directly or indirectly a component of such foods”.

A food additive may be authorized only if it meets the following conditions:

it does not, on the basis of the scientific evidence available, pose a safety concern to the health of the consumer at the level of use proposed;
there is a reasonable technological need that cannot be achieved by other economically and technologically practicable means;
its use does not mislead the consumer.

The use of food additives necessitates the use of appropriate methodologies to determine whether the permissible level has not been exceeded. For this purpose J.S. Hamilton Poland SA uses various techniques – chromatography (gas chromatography, liquid chromatography, thin-layer chromatography), spectrophotometric, spectral (ICP-OES and ICP-MS) and distillation.

AUTHENTICITY

Food is adulterated to increase the quantity and make more profit. Nowadays, the irregularities are detected in almost each foodstuffs, which makes this aspect one of the most important problems. Milk and dairy products, chocolate and chocolate products, meat and meat products, vegetable oils, fruit and vegetable juices, honey and alcoholic beverages may be adulterated.

Wrong declaration on the label related to present of the ingredient that is not declared, no information about the preservatives used, or the incorrectly used of the product name (e.g. “butter” when containing foreign fats other than milk fat) are the most commonly found food fraud. Often a more expensive ingredient is substituted with a cheaper one or not allowed substance in foodstuffs is added (e.g. scandal associated with the addition of melamine to milk for children few years ago).

Detection of food adulterations needs using appropriate techniques – either conventional methods (e.g. determination of the freezing point to detect water dilution in milk or Lugol test to detect starch additive in meat product) or enzymatic, genetic, microscopic and instrumental methods as chromatographic, isotopic, spectrophotometric and spectral techniques.

Choosing the right methodology requires cooperation between the customer and the laboratory, due to the necessity to define not only the analytical technique but also the direction in order to adequately identify the potential food adulteration..

RADIATION

Experiments on food irradiation appeared in the United States before World War II. However, until after World War II the applying nuclear energy in the technology of food preservation expanded dynamically , due to the necessity of peaceful use of the nuclear infrastructure, developed during the war. The food sector saw the potential benefits of extending the shelf life of food products.

Irradiation of food products is the process of exposing foodstuffs to high doses of radioactive cobalt-60 or cesium-137, gamma rays or high speed electron beams. As a result of these actions, the chain reaction inhibits the decay of fruit and vegetables, eliminates the sprouting and ripening, prevents the spread of bacteria and neutralizes impurities.

Food irradiation is permitted, if technically justified, unless it poses a threat to human health.

SHELF LIFE TESTING

Changes that affect the quality of the food, the functional value of the final product, consumer acceptance, and often also on the human health may occur during storage of foodstuffs.

Almost all foods require a shelf-life declaration, i.e. the period of time during which a food, storage under specified conditions, maintains nutritional value, quality indicators (physicochemical and microbiological), which do not exceed the established criteria set by the applicable regulations and the sensory changes do not cause a loss of acceptability.

General food safety requirements, as defined in Regulation (EC) No 178/2002 of the European Parliament and of the Council of 28 January 2002, state that food shall not be placed on the market if it is unsafe, injurious to health or unfit for human consumption.

Shelf life testing should be conducted in the following circumstances:

development of new products,
development of new processes,
preparation of new packaging,
significant change of ingredient(s) or packaging of an existing product,
change of the production place or production device,
no prior shelf-life tests.

Shelf life testing allows to evaluate the range and direction of changes in products over time. The shelf life testing can consist in:

testing of products stored during the designed period of the shelf life – as required by the specifications or standards (temperature, relative humidity, light) and is applicable mainly to low-processed and short-shelf life products.
testing in accelerated conditions i.e. accelerated aging tests, which are carried out under the influence of selected external factors, most often elevated temperature and/or humidity or UV irradiation. Accelerated shelf life testing enables to quickly estimate the product’s durability, but due to simulated conditions it is necessary to confirm the results under standard conditions, in order to verify the safety and quality of the products at the end of the real shelf life.

Conducting of the accelerated shelf life testing to determine durability is not easy. All stages – project development, analysis and final results summaries require direct cooperation between the laboratory and the producer. Due to the many years of experience in this field, J.S. Hamilton Poland SA laboratory may be helpful to producers working in the food market.