Analysis of heavy metal accumulation food with X-Ray fluorescence spectometry

The theme of the study is the examination of heavy metal accumulating ability of commercially available chicken, pork and beef liver samples and comparison with the limits specified by the laws. The measurements were carried out with the Delta XRF device manufactured by Innov-X, which operates on the principle of X-ray radiation. The lead content of all samples of the first and second sampling were beyond the maximum level (0.5 mg/kg) which is required by the Commission Regulation 1881/2006. The measured values were between 2 and 3 mg/kg for both samplings. In case the samples of the third sampling the lead content could not be detected by the applied device. The cadmium contents of the all samples of three samplings exceeded the required cadmium limit in the regulation (0.5 mg/kg). The measured values were between 10 and 20 mg/kg in case of all samples. Tin and mercury contents were not detected in the investigated samples by the applied measurement method. Among the non-toxic heavy metals the samples contained high amounts of iron and manganese, in additional each samples contained small amount of zinc, rubidium and antimony but these does not constitute a health risk due to the minimal amounts

Diafiltration based cow’s milk partial demineralization by membrane filtration process – parameter and technology estimations

Milk and dairy products contain a number of biological materials that are essential for the human body, for example proteins, lipids, vitamins and minerals. In this study the application of membrane filtration based milk partial demineralization is detailed. The main point of the partial demineralization is to reduce the monovalent ions (Na+, K+) but to keep the divalent ions (Ca2+, Mg2+) content. The experiments were carried out using laboratory ultra- and nanofiltration units. Comparing the separation behavior of the membranes it was found that the investigated membranes are suitable for the partial demineralization. The result of the Lowry test showed that the protein concentration is higher in the retentates of all membrane filtrations than in the permeates

Analysis of heavy metal accumulation food with xray fluorescence spectrometry

The theme of the study is the examination of heavy metal accumulating ability of commercially available chicken, pork and beef liver samples and comparison with the limits specified by the laws. The measurements were carried out with the Delta XRF device manufactured by Innov-X, which operates on the principle of X-ray radiation. The lead content of all samples of the first and second sampling were beyond the maximum level (0.5 mg/kg) which is required by the Commission Regulation 1881/2006. The measured values were between 2 and 3 mg/kg for both samplings. In case the samples of the third sampling the lead content could not be detected by the applied device. The cadmium contents of the all samples of three samplings exceeded the required cadmium limit in the regulation (0.5 mg/kg). The measured values were between 10 and 20 mg/kg in case of all samples. Tin and mercury contents were not detected in the investigated samples by the applied measurement method. Among the non-toxic heavy metals the samples contained high amounts of iron and manganese, in additional each samples contained small amount of zinc, rubidium and antimony but these does not constitute a health risk due to the minimal amounts

Investigating the Texture and Antioxidant Capacity of Papain and Trans-glutaminase Enzyme-treated Yogurt with Different Carbohydrates – Glucose, Sucrose and Maltodextrin

Yogurt is considered as a functional food, which is a complex mixture of different biological components. Functional foods are designed to have physio-logical benefits and reduce the risk of chronic diseases beyond basic nutritional functions, and may be similar in appearance of conventional food. Therefore, the consumption of dairy products is highly recommended. In this study, the average composition milk was purchased in a local supermarket. Subsequently, ultrafiltration of milk was carried out with a tubular membrane, placed in a laboratory-developed cross-flow membrane module. Pore size and active surface area of tubular membrane were 5 nm and 0.005 m2, respectively. A static turbulence promoter was placed inside of membrane tube. Retentate of ultrafiltration membrane was treated with different concentrations of papain at temperature 50 °C for 10 minutes and subsequently, deactivation of enzymatic activity was performed at temperature 70 °C for 20 minutes. After deactivation of catalytic activity of papain, milks were fermented with yogurt starter culture (Thermophilic YoFlex® culture) at temperature 45 °C for 6 hours. During fermentation, transglutaminase and different types of carbohydrates, such as glucose, maltodextrin and sucrose were introduced with the aid of changing texture and antioxidant capacity of yogurt. Antioxidant capacity and hardness of yogurt, prepared with cow's milk were 0.44 mmol eqv. ascorbic acid/L and 0.58 Newton, respectively. It was found that application of enzyme (both papain and transglutaminase) and maltodextrin increased the antioxidant capacity of yogurt. Furthermore, it was found that hardness of yogurt was increased by addition of carbohydrate

Modelling the Partial Demineralization Process of Cow Milk by Superpro Designer

Milk and dairy products contain a number of biologically active compounds (proteins, lipids, vitamins and minerals) that are essential for human nutrition. The most common procedures for demineralization are based on ion exchange-, nanofiltration- and electrodialysis-based technologies. In this study, the application of membrane filtration-based partial demineralization of cow milk was investigated and the process modelled. Using design equations, the partial demineralization process was designed and the economy of the process calculated. The modelling and simulation of the partial demineralization process was carried out by the SuperPro Designer programme. As the first step the unit operations of the demineralization technology were defined using the tools of the programme. The SuperPro Designer possesses industrial tools with reactor models, chemical components, a database of mixtures, and price estimations. By analysing the influence of the operation parameters, the feasibility of the proposed process was investigated. From the results of the modelling it can be concluded that the partial demineralization process can be successfully implemented, achieving the expected demineralization rates with a relatively good payback time of two years

Concentrations of Beetroot (<i>Beta vulgaris</i> L.) Peel and Flesh Extracts by Reverse Osmosis Membrane

The objective of this investigation was to concentrate betalains, phenolics, and antioxidants from the extract of peel and flesh of beetroot (Beta vulgaris L.). Thin-film composite reverse osmosis (RO) membrane composed of the thick polyamide barrier layer, microporous polysulfone interlayer, and polyester support web was used in membrane module. In a later exercise, thermo-instability of betalain color compounds was investigated with different temperatures. After the filtration of the aqueous extract of flesh, betacyanins, betaxanthins, and total betalains were increased by 5.2, 6.1, and 5.5 times, respectively. Likewise, the mentioned bioactive compounds were increased by 3.7, 4.9, and 4.2 times after filtration of the aqueous extract of peel. The amounts of total betalains measured in the final flesh extract were two times lower (14.33 ± 0.15 mg·g−1 dm) compared to the peel concentrate (30.02 ± 0.28 mg·g−1 dm). The superior amount of phenolic was shown in the final flesh extract (34.47 ± 0.19 mg GAE·g−1 dm) compared to peel extract (12.74 ± 0.42 mg GAE·g−1 dm). The antioxidant activity in final beetroot peel extract and flesh extract were 24.65 ± 1.42 mg ASE·g−1 dm and 11.6 ± 0.1 mg ASE·g−1 dm, respectively. The recovery of thermo-sensitive bio-colorants was achieved by membrane filtration with the least thermal degradation

Biological Activities of Lactose-Based Prebiotics and Symbiosis with Probiotics on Controlling Osteoporosis, Blood-Lipid and Glucose Levels

Lactose-based prebiotics are synthesized by enzymatic- or microbial- biotransformation of lactose and have unique functional values. In this comprehensive review article, the biochemical mechanisms of controlling osteoporosis, blood-lipid, and glucose levels by lactose-based prebiotics and symbiosis with probiotics are reported along with the results of clinical investigations. Interaction between lactose-based prebiotics and probiotics reduces osteoporosis by (a) transforming insoluble inorganic salts to soluble and increasing their absorption to gut wall; (b) maintaining and protecting mineral absorption surface in the intestine; (c) increasing the expression of calcium-binding proteins in the gut wall; (d) remodeling osteoclasts and osteoblasts formation; (e) releasing bone modulating factors; and (f) degrading mineral complexing phytic acid. Lactose-based prebiotics with probiotics control lipid level in the bloodstream and tissue by (a) suppressing the expressions of lipogenic- genes and enzymes; (b) oxidizing fatty acids in muscle, liver, and adipose tissue; (c) binding cholesterol with cell membrane of probiotics and subsequent assimilation by probiotics; (d) enzymatic-transformations of bile acids; and (e) converting cholesterol to coprostanol and its defecation. Symbiosis of lactose-based prebiotics with probiotics affect plasma glucose level by (a) increasing the synthesis of gut hormones plasma peptide-YY, glucagon-like peptide-1 and glucagon-like peptide-2 from entero-endocrine L-cells; (b) altering glucose assimilation and metabolism; (c) suppressing systematic inflammation; (d) reducing oxidative stress; and (e) producing amino acids. Clinical investigations show that lactose-based prebiotic galacto-oligosaccharide improves mineral absorption and reduces hyperlipidemia. Another lactose-based prebiotic, lactulose, improves mineral absorption, and reduces hyperlipidemia and hyperglycemia. It is expected that this review article will be of benefit to food technologists and medical practitioners