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The aim of this study is to describe the physicochemical properties of Iranian virgin olive oil (Zard, Mari and Phishomi)cultivated in Roodbar, Gilan. There were statistically significant differences for most of the parameters (P < 0.05). The acidity and peroxide value were in the limit established for classification as extra virgin olive oil. The oilof Zard had the highest amount of monounsaturated fatty acids followed by Mari and Phishomi oils. Mari oil proved to havethe minimum value of polyunsaturated fatty acids, and the highest amount of phenolic compounds and oxidative stability. Theoil of Phishomi had the maximum amount of chlorophylls and carotenoids and therefore it had the highest color index. Therewere no significant differences between the cultivars regarding the refractive index (1.469 at 20 °C for all three cultivars).According to the high content of monounsaturated fatty acids, the lowest amounts of polyunsaturated fatty acids and the highestamounts of phenolic compounds as well as the results of a Rancimat assay, it seems that the quality of the oil of Mari cultivaris better than Zard and Phishomi oils and is also more stable against oxidation.Keywords Virgin olive oil – Physicochemical properties – Phenolic compounds – Color index – Refractive index – Oxidative stability
[ Journal of the American Oil Chemists' Society, 2 February 2012, Online First™, - febrero 2012 ]
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Tyrosol (TY), 4-(2-hydroxyethyl)phenol, is an olive oil biophenol with antioxidant activity and positive effects on humanhealth. This study has investigated the interactions of TY with cyclodextrins (CD) and a CD polymer. Complexation of TY withß-CD, hydroxypropyl-ß-CD (HP-ß-CD), and methyl-ß-CD (Me-ß-CD) has been evaluated both in aqueous solution and in the solidstate. The techniques employed in solution to determine the apparent stability constants of the respective complexes werefluorescence and UV–visible spectroscopies. Complexation with ß-CD and its derivatives involved an increase of both the UVabsorbance and the intrinsic fluorescence of TY; a bathochromic shift of the UV spectrum was detected as well. The apparentstability constants obtained with native ß-CD, Me-ß-CD and HP-ß-CD presented similar values. Complexes in the solid statewere obtained by coevaporation and kneading. They were characterised by X-ray diffraction analysis and differential thermalanalysis. The interaction of TY with ß-CD led to a crystalline complex; the same diffraction pattern was obtained by coevaporationand kneading. The complexes obtained with methyl- and HP-ß-CD were amorphous irrespective of the preparation method. In addition,the retention of TY in an insoluble polymer of CD crosslinked with epichlorohydrin has been quantified. In approximately 20 min,1 mg of TY per gram of polymer was retained.Keywords Tyrosol – Cyclodextrin – Inclusion complex
[ Journal of Inclusion Phenomena and Macrocyclic Chemistry, 27 January 2012, Online First™, - enero 2012 ]
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In this work, the opportunity of adopting a differential scanning calorimetry (DSC)-principal component analysis (PCA) coupledprocedure to measure the degree of thermal stress for extra virgin olive oil (EVOO) was presented. Oil was subjected to thermalstress under convectional or microwave heating treatments at different heating times up to 1,440 and 15 min, respectively,and p-anisidine values (PAV) were obtained on all samples to measure their oxidative degradation. The entire DSC profiles obtainedon the oil upon cooling in the range from 30 °C to –80 °C and subsequent re-heating to 30 °C at different times and undercooking procedures have been subjected to PCA data analysis. PCA discriminated samples by means of profile changes in DSCtransition both upon cooling and heating not only according to treatment times (which accounted for the degree of thermo-oxidation)but also considering different heating process. The proposed procedure may be useful to measure oil thermal stress and toselect appropriate heating condition to be applied for EVOO both in industrial and/or in food-catering sectors.Keywords Differential scanning calorimetry – Extra virgin olive oil – Thermo-oxidation – Chemometric procedure
[ Food Biophysics, 25 January 2012, Online First™, - enero 2012 ]
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This report shows notable improvements of soil physical, chemical, and biological properties after long-term soil applicationof olive mill pomace compost. About four million tons of olive mill pomace is produced annually in Andalusia, Spain. Olivemill pomace is a main by-product of the olive oil extraction industry. Composting is a promising strategy to manage the hugevolume of this potentially environmentally harmful pomace. Converting olive mill pomace into a useful soil amendment in semiaridMediterranean areas of olive oil farms, characterized by low organic matter content and subjected to progressive degradation,would be valuable. There is actually no data on the long-term effects of composted olive mill pomace application on soil physicochemicaland biochemical properties. However, this information is needed to encourage the composting of this pomace. Here, a fieldstudy evaluated soil fertility and soil capacity to degrade organic compounds after the application of composted olive millpomace. Olive groves received compost annually for 3, 4, 9, and 16 years. Soils were sampled and compared to olive groveswithout compost application. Soil physico-chemical properties and soil enzyme activities such as acid phosphatase, ß-glucosidase,protease, invertase, and dehydrogenase, were analyzed. Our results show that soil organic matter, nitrogen, available phosphorus,cation exchange capacity, aggregate stability, and exchangeable potassium were between 1.4 and 3.3 times higher in the compost-treatedfarms. Soil enzyme activities in soils treated with compost was between 180% and 420% higher than in untreated soils. Moreover,there was a clear trend of increasing soil fertility and enzyme activities with years of compost application. Here, we concludethat the addition of composted olive mill pomace to olive groves markedly improved soil quality.Keywords Composted olive mill pomace – Soil fertility – Soil enzyme – Olive oil farm – Olive oil industry – By-products
[ Agronomy for Sustainable Development, 25 January 2012, Online First™, - enero 2012 ]
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