ARTIFICIAL SWEETENERS IN VARIOUS FOOD PRODUCTS - QUANTIFICATION AND INTAKE ASSESSMENT

The aim of the study is to determine the content of artificial sweeteners in 133 different food products. The analytical quantification was performed by the application of a reversed-phase, validated, gradient HPLC method, with simultaneous determination of aspartame, acesulfame K and Na-saccharin content. Supelcosil 150 x 4.6 mm, 5µm was used as the stationary phase and mobile phase (buffer 0.1 M NaH2PO4, pH = 2.5 and acetonitrile), at temperature = 26 °C and flow = 1.5 mL/min. The method was applied on: non-alcoholic beverages, chewing gums, sweets, chocolates, confectionery, dietary products, food supplements, fruit yogurt, etc. Depending on the structure of the food, different extraction methods were applied. The assessment of food safety showed irregularity in 21 % of the products, of which 50 % were imported. Some of the products` declarations were not completely translated nor properly labelled. Of the irregular domestic products, 21 % exceeded the maximum permitted quantities of added sweeteners and the rest had irregular labelling. The analysis showed that the most commonly used sweetener was Na-saccharin, which along with aspartame and acesulfame K are most frequently utilized in non-alcoholic beverages. Intake of artificial sweeteners was estimated according to the mean body weight for children, adolescents and adults, under the supposition that the products contained the maximum permitted quantities. The theoretical maximum daily intake of different food products in different population groups indicates the existence of a potential health risk only with continuous "large" intake of products that contain the maximum allowable amounts of artificial sweeteners, especially for the youngest populations

DETERMINATION OF VITAMINS AS ADDITIVES FOR FORTIFICATION OF REFRESHING SOFT DRINKS

Soft drinks are sweetened, based on water, usually contain a certain amount of fruit juice, fruit pulp or other natural ingredients and they have a balanced acidity. Their nutritional and energy value is derived mainly from the content of sugars, but besides them there are also mineral elements, vitamins, enzymes and amino acids in minor amounts. Soft drinks are classified as fruit juices and refreshing beverages. Refreshing beverages can be clear or with pulp. The main ingredient is water, then sugar or artificial sweetener, fruit juice or fruit base or plant based extracts or based on cereals, with addition of carbon dioxide and allowed additives in the prescribed amounts. In recent times a trend is to fortify the refreshing beverages with certain vitamins or minerals. Ascorbic acid is commonly added in food as an antioxidant and stabilizer. The vitamins from B group are water soluble and played a significant role in human metabolism. In addition, it is important to consider the amount of the microelements that are necessary to meet our daily needs as nutrients. The research was made on refreshing beverages fortified with vitamins. The analysis was made on 20 different beverages in 2014, 2015 and 2016. The quantitative determination of the water soluble and fat-soluble vitamins in the refreshing beverages was performed by using by HPLC-DAD method. The vitamin C was determined by iodometric method. In the examined samples were usually present the following water soluble vitamins: В1 (from 0.18 to 0.3 mg/100ml), В3 (from 2.40 to 3.20 mg/100ml), В5 (from 0.8 to 1.04 mg/100ml), В6 (from 0.20 to 0,37 mg/100ml) and the vitamin С (from 9.06 to 16.41 mg/100ml), and more rarely were present vitamin В2 (from 0.22 to 0.28 mg/100ml) and the liposoluble vitamin Е (from 0.7 to 1.33 mg/100ml)

CHANGES OF NUTRITIONAL PROPERTIES OF THREE VARIANTS PEPPERS BY PROCESSING OF PICKLED RED PEPPERS

 Blanching was done at 85-90 °C for 5 min. To the pasteurized pepper, acetic acid was added at a concentration of 1.5 % in terms of finished product, which belongs to the low marinated products. Pasteurization is carried out at T 92 °Cfor 30 minutes. The chemical properties were determined by analyzing the following parameters: total dry matter, carbohydrates, proteins, oils, total acids, vitamin C, β-carotene and ash, both in fresh and in pasteurized peppers. Based on the obtained results the quality and nutritional composition were determined. The variety horgosh shows the highest content of total dry matter (11.45 %), vitamin C (138.9 mg/100 g), βcarotene (22.7 mg/100 g), and the highest energy value (41.7 kcal). In the gourp of the pasteurized peppers, the variety of palanechko chudo has been characterized by the lowest average value of total dry matter (7.49 %) and lowest total energy value (24.6 kcal); the variety of kurtovska kapija had the lowest contents of vitamin C (52.1 mg/100 g) and β-carotene (6.09 mg/100 g)

COMPARING THE QUALITY PROPERTIES OF FRESH AND DRIED APPLE FRUIT - VARIETIES PINOVA AND RED DELICIOUS

The quality and the nutritional composition of fresh and dried apple fruits of the varieties pinova and red delicious were tested. The apples were grown in the region of Bitola in the Republic of Macedonia. The fruits were harvested manually after the visual assessment on terrain and after determination of harvesting time. After analyzing the mechanical and chemical properties of the fresh fruit, the fruit was prepared for drying. The treatment of the raw material was done with 0.1 % solution of citric acid and 0.5 % solution of K2S2O5, with time of immersion of five minutes. In order to compare the impact of applied treatments on the tested chemical properties, we also applied a variant of untreated fruit (control). Drying was performed in a chamber dryer from the type S-100, at a temperature between 65 °C to 70 °C for 6 to 8 hours. From the chemical composition of fresh and dried apple fruit, we examined: the total dry matter, total sugars, total acids, vitamin C, pectin, flavonoids, tannins and mineral matter. The fresh fruits from the pinova variety were characterized by better mechanical properties (weight 137.35 g, height 62.56 mm, width 68.78 mm) compared to the fruits of the red delicious variety. In fruits from this variety there were higher values 14.16 % for: total sugars, 0.34 % total acids, flavonoids 2.66 µg/g, tannins 1.39 µg/g and mineral matters 0.25 %. After the analysis of dried apple fruits, the varieties of pinova and red delicious, the higher content of vitamin C was found in fruits treated with 0.5 % solution of K2S2O5. The process of drying in a chamber drier enabled preservation of the chemical properties and getting a quality final product

QUANTIFICATION OF CAROTENOIDS IN SOME VARIETIES OF RED PEPPERS (CAPSICUM ANNUM L.) AND THEIR PROCESSED PRODUCTS

The red pepper (Capsicum annuum L.) is one of the most essential vegetable crops due to multiple ways it can be processed, as well as for the content of the nutritional phytochemicals, such as carotenoids, which are important for human health. Carotenoids are responsible for the pepper’s colour, as natural antioxidants. They are present in relatively high amounts in the ripe fruit and they play a positive role to ensure the colour stability of the final product.This research examined the carotenoids composition of the red pepper varieties: kurtovska kapija, palanechko chudo and horgosh. For each of the varieties, the following preservation technologies have been applied: pasteurization, freezing, and drying. The extraction method of carotenoids was performed by using methanol-dichloroethan and anhydrous Na2SO4. The changes in the carotenoid pigments of examined varieties during processing have been investigated quantitatively by usage of HPLC technique. The HPLC method was performed on stationary phase Nucleosil 100-3 C18, 250 x 4,6 mm, with a flow rate: 0,7 mL/min, and the gradient program with following eluents: methanol, distilled water and a mixture of isopropanol, acetonitrile and methanol. Carotenoids have been detected between 200 and 700 nm. In all of the analyzed samples, 47 peaks of carotenoids were detected, of which 5 were unknown, one was mixed, and 41 carotenoids were identified. The red pepper variety horgosh was found to contain the highest content of total carotenoids in fresh pepper fruits (690,15 µg/g), frozen pepper (587,88 µg/g), pasteurized pepper (575,76 µg/g) and dried pepper (493,94 µg/g)

Proficiency Testing Activities; Experience of a Laboratory for Food Quality Control

The Institute of Public Health is the first public health institution in the FYROM that has established Quality Management System according to ISO/IEC 17025. The accreditation has been granted by the National Institute for Accreditation in December 2006. Since then, the maintenance and improvement of the Quality Management System remains a key element in our policy. It is well-known that one of the elements by which laboratories can demonstrate their competence is through participation in Proficiency Testing (PT) activities. Therefore, our laboratory adopted practice to participate in at least one PT scheme relating to each sub-discipline per a year. Since the first accreditation, our laboratory participated in 15 PT schemes, organized by different providers, such as: Muva Kempten Quality Management & Laboratory Services; FAPAS; DRRR Deutsches Referenzbüro für Lebensmittel-Ringversuche und Referenzmaterialien; LGC; Asia Pacific laboratory Accreditation Cooperation etc. The most frequently analyzed matrices were: cream, powdered milk, yoghurt butter, cheese, oily dressing, soft drinks, cabbage puree; while the most analyzed parametres were: fat and water content, dry matter, protein content, pH, benzoic acid, nitrates, caffeine, saccharine, potassium acesulfame, citric acid, fructose, glucose, sucrose, total sugars. Total of 60 parameters were tested, and 49 from the obtained results (81.7%) were evaluated as satisfactory, 2 results (3.3%) were assessed as questionable, while 9 (15.0%) were evaluated as unsatisfactory. The investigation shown that unsatisfactory performance is most frequently due to the systematic errors, such as: improper matrix homogenization, incomplete extraction or inadequate drying and cooling of glassware to constant temperature