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51.
Four proteins, α/β globulin, serum albumin, γ‐globulin and fibrinogen, were isolated from bovine blood and hydrolysed using papain. Hydrolysates were assessed for non‐cellular and cellular antioxidant activity. The anti‐proliferative activity of hydrolysed fractions was assessed in a number of cancer cell lines including U937 lymphoma cells, MCF‐7 breast cancer cells, HepG2 hepatocytes and Caco‐2 epithelial colorectal adenocarcinoma cells. Anti‐inflammatory activity of the hydrolysates was also assessed. Hydrolysates generated from γ‐globulin or fibrinogen had significant antioxidant activity in non‐cellular assays. Hydrolysates were also found to be highly toxic to different cancer cell lines, in particular U937 lymphoma cells when assessed using the MTT assay. The fibrinogen hydrolysate was the most toxic sample and toxicity appeared to correlate with its non‐cellular antioxidant activity. None of the hydrolysates had significant anti‐inflammatory activity. The high cytotoxicity of the γ‐globulin and the fibrinogen hydrolysates towards cancer cells may indicate a potential use as anti‐proliferative agents.  相似文献   
52.
Meat products made from liver of poultry like duck and goose are popular and often sold as specialities for high prices. As the prices for the basic raw material are high, fraud may be attractive for producers. To prevent consumers from fraud, official control authorities survey such products. In this work, a quantitative multiplex PCR was developed determining the proportion of DNA and meat fractions of turkey, chicken, duck, goose and pork. The precision and accuracy of the PCR system was investigated. To examine the possibility of determining the meat fractions according to the recipe, reference material was produced and different liver–meat products from the market were analysed. For major components, the measurement uncertainty revealed to be at 39 %. For minor components, it was estimated to be 124 %. The results showed that this pentaplex real-time-PCR system is suitable to control the meat properties of such products although measurement uncertainty may be high.  相似文献   
53.
Beef processing produces high volumes of protein rich, low value, ‘waste’ co-products such as offal. Beef improves uptake of low bioavailable non-haem iron (found in vegetables, fortificants, supplements) and this effect is dubbed the ‘meat-factor’, although the underlying mechanism is not fully understood. Here, we investigate whether bovine co-products (kidney, lung, heart) not previously studied share this enhancing potential. This was determined by coupled in vitro digestion of co-products and subsequent caco-2 cell ferritin formation (an intracellular iron storage protein). In this study we show that bovine co-products significantly increase caco-2 cells’ response to non-haem iron from infant rice cereal. The presence of these co-products, (kidney, lung and heart), increased relative uptake (by 207.13%, 171.21%, 265.28%, respectively), to a greater extent than beef (30.23%). Our findings present a novel function for co-products of beef processing that may have potential as food ingredients to improve non-haem iron bioavailability, thus adding value.  相似文献   
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Pectin was acid-extracted from low quality ‘Golden Delicious’ apple fruit, yielding 16% (w pectin/w apple fruit). Composition and some of its physicochemical and functional properties were assessed. The pectin fraction presented a galacturonic acid content of 65% (w/w), an esterification degree of 57%, an intrinsic viscosity, [η], of 307 ml/g and a molecular weight (Mw) of 112 kDa. Pectin gels were obtained in 60% (w/v) fructose and pH 2.7. Pectin gels at 2.0% and 3.0% (w/v) presented hardness values of 10.2 and 20.4 g after 12 h at 4 °C. The gel hardness was greatly affected by aging (20% and 25% decrease in 48 h for gels at 2% and 3%, respectively). The results attained suggest the use of this gum as a potential texturing agent for the food industry.  相似文献   
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Raspberry pomace extracts isolated with supercritical carbon dioxide (SCE) and pressurised ethanol/water (ETE) were tested in beef burgers. Only ETE additives effectively inhibited lipid oxidation and the growth of microorganisms, as it was observed by measuring the changes of thiobarbituric acid reactive substances, bacterial counts and the content of O2 and CO2 during storage in the modified atmosphere package. ETE additives also demonstrated some meat colour preservation effects, which were assessed by the intensity of hamburger colour and metmyoglobin concentration. However, ETE additives did not alter burger's taste at the applied concentrations (up to 1%). It may be concluded that the most effective extracts possessing strong antioxidant and antimicrobial activity may be isolated from raspberry pomace by the pressurised liquid extraction with a hydroethanolic solvent; such extracts may be considered as promising additives in meat products for improving their stability and enriching with beneficial to health phytochemicals.  相似文献   
59.
Forty-two cultures of Bacillus species isolated from soybean dawadawa were screened for their proteolytic activity on Skim Milk Agar, amylolytic activity on Starch Agar, and ability to grow on Soybean Agar. Distinct differences were observed between the cultures for all the criteria. Eleven isolates were selected for laboratory fermentation trials and each produced soybean dawadawa which was found acceptable by a taste panel. The pH of the samples, which increased from 6.37-6.58 to 8.22-8.85 during fermentation, were significantly different at P< or =0.05 for the different cultures. In the fermented samples, Bacillus counts exceeded 10(9) cfu/g, with the population of only one sample being significantly different at P< or =0.05. A market focus group familiar with soybean dawadawa selected Bacillus subtilis 24BP(2) and B. subtilis FpdP(2) as the best potential starter cultures. A taste panel found no significant differences in overall acceptance between soybean dawadawa either fermented spontaneously or with B. subtilis 24BP(2) and also between soybean dawadawa fermented with either B. subtilis 24BP(2) or B. subtilis FpdP(2).  相似文献   
60.
The only current effective treatment for coeliac disease (CD) is a lifelong diet that is as free from gluten as possible. This study provides baseline evidence to inform future interventions of benefit to CD sufferers by examining awareness of CD issues by food servers and preparation staff, assessing their claims to provide gluten‐free foods by analysis of a meal concurrently sampled. While the majority of attempts to purchase a ‘gluten‐free’ meal on request in restaurants were successful, some 10% of all samples contained gluten, 2.7% between 21 and 100 mg kg?1, and 7.7% >100 mg kg?1 and two unsatisfactory samples were purchased from so‐called coeliac‐friendly restaurants. These findings were consistent with those obtained previously by Collin et al. [Alimentary Pharmacology & Therapeutics 19 (2004) 1277], Størsrud et al. [European Food Research & Technology 217 (2003) 481], Gélinas et al. [International Journal of Food Science & Technology 43 (2008) 1245] for cross contamination with gluten. Staff confidence, ‘gluten‐free’ notices, signs and menu choices were no guarantee of risk‐free dining for CD sufferers. Based on our findings we suggest the need for further training, specifically for chefs and managers.  相似文献   
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