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Volume 14, Issue 1, 2025
Online ISSN: 2182-1054
Volume 14 , Issue 1, (2025)
Published: 31.07.2025.
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Contents
18.10.2012.
Original scientific paper
Differences in quality parameters between types of commercial tea from Argentina
To determine differences in quality parameters between different types of tea elaborated in Argentina, water extract, crude fibre, caffeine, total polyphenol content, antioxidant activity, sorption isotherms and colour parameters (L, a, b) were determined. Fifty-one industrial samples of commercially available teas including green tea, semifermented tea, black tea and black tea sub-product (BTSP) were used for this study.Water extract contents were significantly higher in black tea and green tea (40.3% and 40.7% w/w, respectively), while semifermented tea and BTSP showed higher levels of crude fibre (22.3% and 20.4% w/w, respectively). Caffeine contents of black teas (2.7% w/w) were significantly higher than in the other types of tea. Green teas revealed the highest concentrations of phenolic compounds and the major antioxidant activities (14.9 g GAE/100g dm and 30.0 g AAE/100g dm, respectively). The results also highlighted significant differences (p<0.05) in colour values between the different types of tea.
Ana Thea, MarĂa Antonia Lloret, Luis Alberto Brumovsky, Miguel Eduardo Schmalko
01.12.2011.
Professional paper
Treatment of Olive Mill Wastewater and the Use of Polyphenols Obtained After Treatment
Olive mill wastes are signicant environmental problem especially in Mediterranean areas where they are generated in huge quantities in a short period of time. They are phytotoxic materials because of their high phenol, lipid and organic acid concentrations, but these wastes also contain valuable resources that could be recycled such as a large proportion of organic matter and a wide range of nutrients. The effluent from olive oil mills contains a large amount of polyphenols that have antioxidant properties. The market value of these antioxidants is high and they are commonly used in the food, cosmetics, pharmaceutics and chemical industries. For the management of olive mill wastewater (OMW) and other olive residues, various treatment methods can be used. Many scientists work on more efficient and cheaper treatment alternatives. Due to the great variety of compounds in the waste, several technologies to remove the harmful compounds for the environment should be used single or together. Some of the most used OMW treatments are drying / evaporation, forced evaporation, thermal treatment, centrifugation-ultraltration, electrocoagulation, composting, lagooning, adsorption, powdered activated carbon, filtration, sand filtration, membrane filtration, ultrafiltration, precipitation / flocculation, distillation, electrolysis, co-composting, advanced oxidation processes (AOPs) such as ozonation, hydrogen peroxide / ferrous iron oxidation (the so-called Fentons reagent). Several OMW treatment technologies have been developed aiming at the removal of the main toxic organic compounds. A lot of factors must be considered to choose the treatment methods among them the investment, required area, specic training of the workers, noise and odour emissions and seasonality of production.
Semih Otles, Ilknur Selek
01.12.2011.
Professional paper
Challenges and Opportunities for the community of Food Sciences to contribute Towards a Society of Healthier Consumers and a Better World
Harris N. Lazarides