| Abstract [eng] |
The aim of this study is to determine the impact of various factors which affecting of vitamin A and D amounts in food matrices. During the study was research food product were where fat soluble vitamins A and D3 are being find naturally. The other group of the research products were fortified with vitamin D3. As rich sources of these vitamins are considered only a few food products, for this reason the main products used for the research are widely used dairy products and fish. Cold water–soluble vitamin D3 fortified apple juice, which does not contain vitamin D3 naturally. The amounts of the vitamin A and D3 in foodstuffs was determined by using reverse phase high performance liquid chromatography, after the 16–hours sample hydrolysis (20 °C in the dark), then the next liquid–liquid extraction with hexane, evaporation to a dry residue which was dissolved in the mobile phase. Both of fat–soluble vitamins can be separated by the same chromatographic separation time only recording chromatograms at different wavelengths. Twelve months have been studied to the same cows were divided into groups according to the holstein grade of milk. The data showed that the largest average of vitamins D3 and A typical value of 3 group of cows milk (holstein grade – H70–79), while the lowest – 4 group (H80–89). The average value of vitamin D3 was 1,27 µg/100g in the third and 0,67 µg/100g in the fourth group, vitamin A were respectively 108,89 ir 67,66 µg/100g. First group of cows milk with holstein grade in H0–49, average of vitamins content was 1,13 µg/100g D3 and 78,51 µg/100g A. Assessing the impact of seasonality on vitamin content in milk showed that a statistically significant mainly vitamin D3 in milk was in the summer period (1,56 µg/100g), another period when 26–52 % less. Vitamin A content of another full year within a wide range, from 26,14 to 216,19 µg/100g, so the statistical analysis showed no significant seasonal factors. On the small–scale laboratory conditions in two different ways (acid–enzymatic or acidic) produced curd was enriched by water or fat soluble crystalline colecalciferol. It was found that the solubility of added vitamin had no effect on the recovery of vitamin D3 in curd. The differences in vitamin recovery were caused by the method of curd production. In the curd samples made by acid–enzymatic method the vitamin D3 recovery was 81,8 %, and in curd produced by acid – 61.9%, which is 20 % less. Producing curd by acidic coagulation, bigger amounts of vitamin moves to whey, comparatively to the acid–enzymatic coagulation curd. Commercially produced condensed milk was enriched by different forms of vitamin D3 preparations. It was important to determine whether the vitamin are distributed evenly condensed milk volume. Cold water–soluble vitamin D3 preparation (2,44 μg/100g) was added to the condensated milk before sterilization. Determinate equal vitamin distribution in all production line: beginning – 2,39±0,41, in the middle 2,47±0,56 and at the end 2,53±0,34 µg/100g. Two months of vitamin D3 concentrations in different party places selected samples remained substantially unchanged. The same result about vitamin distribution in condensated milk obtained before sterilization insert fat–soluble vitamin D3 preparation (1,75 mg/100 g). At baseline set added vitamin D3 concentration in all product is 1,61±0,21 µg/100g remained unchanged two months – 1,63±0,29 µg/100g. Vitamin form (solubility), sterilization and storage in the dark at 4 °C had no effect on the amount of vitamin in the product, slight changes in set values were insignificant and is associated with the test method uncertainty Apple juice was fortified by water–soluble vitamin D3 preparation 100 CWS / AM (DSM Nutritional Products, the Netherlands), vitamin insertion before and after pasteurization. Juice samples stored at 4 °C in the dark and light storage conditions, it was examined the influence of vitamin stability. Added vitamin content was 9 µg/100 g of juice. It was found that heat treatment had no effect on the recovery of vitamin in the product: before pasteurization insert vitamin recovery by the average was 88,22%, followed by pasteurization – 85,56%, but this difference is not statistically significant. Every 7 days researching storage of samples showed that in the dark at 4 weeks of vitamin amount remained stable, but the 4187 lux illumination greatly reduced the amount of vitamin D3 in juice. After only 14 days of vitamin decreased 2,1–2,3 times: from 7,94 to 3,78 and from 7,70 to 3,38 to µg/100g. After 30 days of storage vitamin concentration in juice decreased 3 times, inserted vitamin D3 in juice left 2,70–2,72 µg/100g (34–35%). Studies of food products fortification by fat and water soluble vitamin D3 forms publicity in France in 2017 at the conference \"16th Fat Sluble Vitamins Congress. Research fat–soluble vitamins A and D3 amounts in the fish, found that greater fat green fish – mackerel found much higher vitamin D3 (0,16 µg) and A (119,69 µg), content in dry weight, comparison to those vitamins content less oily pike respectively: 0,07 and 50,80 µg. |
