| Contribution of the research
sphere to the issues of food adulteration A very interesting information regarding problems of food adulteration was published on web pages of the Czech Agricultural and Food Inspection (http://www.czpi.cz/) at the beginning of this year. As an introduction, the "history of food adulteration", the present state of proving of foodadulteration abroad including basic legal regulations, and typical examples of adulteration of food and agricultural products are briefly recapitulated. Furthermore, the present situation of protection of Czech consumers is characterized and the most frequent cases of food falsification in the Czech Republic having been revealed within the inspection activity of the Czech Agricultural and Food Inspection (ÈZPI) are given. On the basis of experience in EU countries it is also stated here that in the future a situation is expectable when we will find more and more foreign or inland falsified food products in the Czech market, while modern, mostly very expensive laboratory methods will have to be used to reveal them. Particularly in connection with laboratory testing we would like to point out that the Ministry of Agriculture of the Czech Republic responded to this fact as early as 1997 when Phased Project EE7143 called "Issues of adulteration in the food quality control system in the Czech Republic, with a view to development of analytical methods" was ordered from the research sphere through the mediation of the National Agency for Agricultural Research (NAZV). Four organizations are participating in solution of the project by means of four independent projects, namely:
The whole phased project is co-ordinated by the Food Research Institute Prague. In the following text we would like to state results achieved so far, or expected (the project will be over in 1999). Department of Food Preservation and Technology of Meat, the Institute of Chemical Technology Prague Attention has been paid to development of analytical methods for evidence of adulteration of ketchups and fruit juices with high portion of fruit. Adulteration of ketchups - adherence to purée portion in accordance with Decree No. 332/1997 of the Digest. On the basis of analyses of products in the Czech market and thanks to co-operation with prestigious manufacturers (Kand, Otma, Spak) who supplied samples with known percentage of purée, a method of calculation of tomato content from selected analytical parameters (lycopene, pyrrolidoncarboxylic acid, potassium, citric acid, malic acid, formol number) has been designed. In spite of relatively narrow calibration set (11 samples), the content of tomato portion, or of dry-matter carried by tomatoes, can be determined with an accuracy of one percent (it is possible to recognize a portion of 6% instead of 7%). The method are being further developed, testing will be repeated with a higher number of calibration samples. After confirmation of the results, validation of the method will be performed and a methodical Czech National Standard (ÈSN) enabling to test quality of ketchups will be probably created. Fruit juices with high portion of fruit. The results of analyses performed have confirmed a higher extent of utilization of pulpwash especially in citrus juices of lower price categories. It is true that juice with addition of pulpwash remains 100% juice but the given situation causes an unsound situation in the market and consumers do not buy standard products. Together with the Union of Manufacturers and inspection authorities we are preparing an initiative to resolve this problem; a variant is to create a Czech National Standard anticipating the Code of Practice. A manufacturer could acknowledge the given standard by some products; in this way it would be obvious e. g. that at a higher price high-quality fruit juice is sold, while other products have a characteristic taste due to higher portion of pulp. At the present time a set of samples of fruit spreads is analyzed as well. Research Institute of Veterinary Medicine The project follows up with research works in the sphere of meat products having been worked out in the Research Institute of Veterinary Medicine since 1993. A laboratory for detection of food adulteration has been established in the institute as well. This laboratory works within the framework of the methodical and counselling centre specialized in development of immunochemical, electrophoretic, and molecularly-biologic methods able to detect possible adulteration of food, especially heat-processed meat products and feed-stuffs. Development of CIE method (opposite electrophoresis) and ELISA method has been completed to distinguish poultry, beef, pork, horse, sewer-rat, kangaroo and escargot meat in heat-processed meat products. ELISA method is being completed for identification of soya proteins in heat-processed meat products as well. PCR (polymerase chain reaction) method for identification of species-specific beef DNA in meat products as well as in meat-bone meals is being verified. This method will serve also for testing of feed-stuffs for cattle where addition of meat-bone meals is forbidden by the EU within the framework of prevention of BSE (bovine spongiform encephalopathy). The CIE and ELISA methods will be completed in the form of kits on the basis of an agreement with the Test-Line company. At present they are used mainly for needs of the National Veterinary Station of the Czech Republic (SVS ÈR), district veterinary stations (OVS), customs laboratories and some meat combines. They have not been introduced into the national system of food quality control so far. Research Institute of Sugar Industry, a. s. The objective of the project was to suggest a method, or a set of methods, to determine genuineness (authenticity) of refined sugar and to distinguish it from affinated sugar. On the basis of statistically processed results of analyses of 66 samples of refined sugar and 31 samples of affinated sugar from sugar-beet seasons of 1996 and 1997, a method of determination of ash content has been suggested as a decisive method and standardized; in case of refined sugar the ash content must not exceed 0.01 %. As regards determination of colour of sugar solutions, it has been found that this method does not provide reproducible results under all conditions, in part due to possible presence of turbidity which is difficult to remove, and further at determination of low concentration of colour substances in raffinades which is burdened with a big error. Polarographic test is recommended as an auxiliary method and a standard operational procedure has been elaborated for this test. The methods elaborated are available in the Research Institute of Sugar Refining, a. s., they, however, have been used only sporadically so far. Food Research Institute Prague In the first two years attention was directed at a proof of authenticity of pure instant coffee and a proof of adulteration of sunflower oil and soybean oil by rapeseed oil. To test limit contents of saccharide markers (free mannitol and total glucose or xylose) used for a proof of authenticity of pure instant coffee, a HPLC method with refractometric detection has been elaborated. Within the framework of market research it was ascertained that this type of falsification occurs at most at foreign instant coffees packed in the Czech Republic, where only one sample of seven samples examined was full instant coffee. From this fact it can be deduced that in this case Czech importers probably do not carry out sufficient testing of authenticity and rely on data declared by the suppliers. On the other hand, only one sample of instant coffees imported by prestigious importers in original package of 10 samples did not comply with criteria of authenticity. As regards two samples of instant coffee of home provenance, in this case one of the manufacturers came into the market with falsified coffee, the other one with authentic coffee. A possibility of employment of erucic acid, a-linolenic acid and brassicasterol as markers for a proof of falsification of sunflower oil and soybean oil by rapeseed oil has been verified. From results of the analyses it has followed that erucic acid and a-linolenic acid can be used only as auxiliary markers of presence of rapeseed oil. Brassicasterol has proved to be a very conclusive marker. It is not present in sunflower-seed oil and soya oil, while in rapeseed oil it has been found in an average quantity of 1400 mg/kg. In addition, there is a possibility of calculation of the probable amount of rapeseed oil added. On the basis of results of market research it may be concluded that sunflower oils and soybean oils of home as well as foreign provenance (or they mixtures), containing higher or lower addition of rape-seed oil (3-25 %) are often sold in this country. Presence of brassicasterol was evidenced at 18 samples of inland sunflower and soybean oil of 20 samples tested, 7 samples of imported oils out of 10 were authentic. Standard operational procedures have been elaborated for both the above-mentioned methods and handed over to the Czech Agricultural and Food Inspection (ÈZPI) as issues of the project. In 1999 analytical methods for a proof of authenticity of pure butter and for distinguishing of milk processed by UHT method from sterilized milk should be completed. In addition to the above-mentioned phased project, two more project were adopted in 1998 by the National Agency for Agricultural Research (NAZV) to support solution of the problems of food falsification, namely Project EP9411 "Elaboration of a set of analytical methods for proofs of adulteration of bee honey" (responsible body: the Food Research Institute Prague, joint responsible body: the Research Institute of Bee-keeping Dol, s. r. o.), and Project EP9179 "Methods for assessment of conformity and for detection of food falsification" (responsible body: the Department of Food Preservation and Technology of Meat, the Institute of Chemical Technology Prague) aimed at proofs of content of muscular proteins in meat products. In conclusion we would like to state that we conform to the necessity of modern solution of the problems of food falsification in connection with protection of consumer's interests, support of fair business and increase of competitive ability of Czech food products in the Czech market as well as in foreign markets. Moreover, these issues are priorities that are essential for our entrance into world economic structures, particularly into the EU. Although the foundation has been laid by means of adoption of the Law on Foods No. 110/1997 of the Digest and follow-up decrees, we expect a lot of work in this field. In addition to development or implementation of analytical methods for evidence of declared authenticity of Czech as well as foreign foods, including observation of new possibilities of their falsification, it is necessary to create such market environment in this country where it will be possible to obstruct falsifiers' machinations in an effective way. In our opinion, not only top state administrative institutions and supervisory authorities controlled by them, which are irreplaceable in this role, but also other organizations such as leagues and unions like in EU countries (e. g. the Association for Protection of Consumers, various associations of food manufacturers, Business Union, etc.) should participate in this activity. |