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Green Olives (green + olive)
Selected AbstractsA SIMPLE METHOD TO DETERMINE DIFFUSION OF SODIUM IN THE EPIDERMIS OF GREEN OLIVESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2004CARLOS ALBERTO ZURITZ ABSTRACT The present study reports a simple method, both mathematical and experimental, to determine variable effective diffusion coefficients for sodium through the skins of olives. Skins removed from green olives, variety Arauco (also known as Criolla), were studied using a lye concentration of 2.25% (w/w) of NaOH at 20C. The diffusion of sodium was evaluated through fresh skins and previously alkali-treated skins. The measured values of effective diffusion coefficients for untreated (fresh) olive skins increased two orders of magnitude during the processing time, from 10,12 to 10,10 m2/s. Whereas, the effective diffusion coefficients determined for previously treated olive skins were of the order of 10,10 m2/s and increased very little with treatment time. [source] DETERMINATION OF VARIABLE DIFFUSION OF SODIUM DURING DEBITTERING OF GREEN OLIVESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2004MARIELA BEATRIZ MALDONADO ABSTRACT Time-variable average effective diffusion coefficients of sodium in the skin and flesh were determined using Macroscopic Mass Balances from experimental data obtained during debittering of green olives, variety Arauco at temperatures of 15, 20 and 25C and lye concentrations of 1.50, 2.25 and 3.00% of NaOH. The effective diffusion coefficient of sodium increased with treatment time at both surfaces of the skin, while it varied very little within the flesh, and in many cases, remained almost constant during the debittering process. In general, the diffusion coefficients determined in the present study were within an order of magnitude of 10,10 m2/s for the flesh during most of the treatment time, while for the skin, they were of the order of 10,12 m2/s for the initial treatment times. Macroscopic mass balances are a simple mathematical method that can be used in lieu of more common numerical techniques, to evaluate variable diffusion coefficients providing accuracy and greater detail of the whole phenomena. [source] Use of a lactic acid bacteria starter culture during green olive (Olea europaea L cv Ascolana tenera) processingJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2005Vincenzo Marsilio Abstract Among the Italian olive germplasm, ,Ascolana tenera' is one of the best varieties for table olive production. This research addressed the impact of different processing types (Greek-style and Spanish-style) on the fermentation and phenolic composition of olive fruit. In particular, the effects of a lactic acid bacteria (LAB) starter culture on the fermentation of naturally green olives processed according to the traditional Greek method were studied. Results revealed that Spanish-style processing produced a dramatic loss of total phenolics, while natural olive processing favoured a higher retention of biophenols. Oleoside 11-methylester, a phenol-related compound, and hydroxytyrosol, tyrosol, vanillic acid, 3,4-dihydroxyphenylglycol, oleuropein and oleuropein aglycons, as the main phenols, were detected in olive fruit. More interestingly, this research indicated that inoculation with LAB affected the pH, total acidity, microbial profile and palatability of olives. Olives fermented with the LAB starter culture were perceived by panellists to be less bitter and more aromatic than those spontaneously fermented. Thus the use of LAB inoculants during olive fermentation could be applied with the currently available technology. Copyright © 2005 Society of Chemical Industry [source] Characterization and chemometric study of crude and refined oils from table olive by-productsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 6 2008M. Victoria Ruiz-Méndez Abstract Table olive processing produces defective fruits and the conditioning operations give rise to solid by-products which are processed to obtain oil. In this study, the most relevant characteristics of crude oils extracted from table olive by-products were high average acidity values (4.5%, green olives; 8.1%, ripe olives), ECN42 values of 0.34 (green olives) and 0.10 (ripe olives), while 2-mono-palmitin averaged 0.92%. The overall content of sterols was 2257,mg/kg (green olives) and 1746,mg/kg (ripe olives), while the concentration of cholesterol was 36,mg/kg (green olives) and 19,mg/kg (ripe olives). The effect of refining was mainly reflected by a decrease in acidity and sterols. Although most characteristics were in agreement with the established regulation for olive oil, the overall trans fatty acid content, the low apparent ,-sitosterol content, and the relatively high cholesterol content prevented their inclusion into classes of crude or refined lampante or pomace olive oils, not even into the vegetable oil category. Therefore, the oils analyzed should be considered for non-edible purposes. The physicochemical characteristics used for chemometric discrimination permitted discrimination among types of oils (crude, 100%; physically refined, 90%; chemically refined, 100%), elaboration styles (green and ripe olives, 100%) and cultivars (Gordal, Manzanilla, Hojiblanca and Cacereña, 100%), with the sterol composition being the most useful parameter for discrimination. [source] A SIMPLE METHOD TO DETERMINE DIFFUSION OF SODIUM IN THE EPIDERMIS OF GREEN OLIVESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2004CARLOS ALBERTO ZURITZ ABSTRACT The present study reports a simple method, both mathematical and experimental, to determine variable effective diffusion coefficients for sodium through the skins of olives. Skins removed from green olives, variety Arauco (also known as Criolla), were studied using a lye concentration of 2.25% (w/w) of NaOH at 20C. The diffusion of sodium was evaluated through fresh skins and previously alkali-treated skins. The measured values of effective diffusion coefficients for untreated (fresh) olive skins increased two orders of magnitude during the processing time, from 10,12 to 10,10 m2/s. Whereas, the effective diffusion coefficients determined for previously treated olive skins were of the order of 10,10 m2/s and increased very little with treatment time. [source] DETERMINATION OF VARIABLE DIFFUSION OF SODIUM DURING DEBITTERING OF GREEN OLIVESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2004MARIELA BEATRIZ MALDONADO ABSTRACT Time-variable average effective diffusion coefficients of sodium in the skin and flesh were determined using Macroscopic Mass Balances from experimental data obtained during debittering of green olives, variety Arauco at temperatures of 15, 20 and 25C and lye concentrations of 1.50, 2.25 and 3.00% of NaOH. The effective diffusion coefficient of sodium increased with treatment time at both surfaces of the skin, while it varied very little within the flesh, and in many cases, remained almost constant during the debittering process. In general, the diffusion coefficients determined in the present study were within an order of magnitude of 10,10 m2/s for the flesh during most of the treatment time, while for the skin, they were of the order of 10,12 m2/s for the initial treatment times. Macroscopic mass balances are a simple mathematical method that can be used in lieu of more common numerical techniques, to evaluate variable diffusion coefficients providing accuracy and greater detail of the whole phenomena. [source] Use of a lactic acid bacteria starter culture during green olive (Olea europaea L cv Ascolana tenera) processingJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2005Vincenzo Marsilio Abstract Among the Italian olive germplasm, ,Ascolana tenera' is one of the best varieties for table olive production. This research addressed the impact of different processing types (Greek-style and Spanish-style) on the fermentation and phenolic composition of olive fruit. In particular, the effects of a lactic acid bacteria (LAB) starter culture on the fermentation of naturally green olives processed according to the traditional Greek method were studied. Results revealed that Spanish-style processing produced a dramatic loss of total phenolics, while natural olive processing favoured a higher retention of biophenols. Oleoside 11-methylester, a phenol-related compound, and hydroxytyrosol, tyrosol, vanillic acid, 3,4-dihydroxyphenylglycol, oleuropein and oleuropein aglycons, as the main phenols, were detected in olive fruit. More interestingly, this research indicated that inoculation with LAB affected the pH, total acidity, microbial profile and palatability of olives. Olives fermented with the LAB starter culture were perceived by panellists to be less bitter and more aromatic than those spontaneously fermented. Thus the use of LAB inoculants during olive fermentation could be applied with the currently available technology. Copyright © 2005 Society of Chemical Industry [source] The antioxidant activity and stability of the phenolic fraction of green olives and extra virgin olive oilJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2001Turkan Keceli Abstract The antioxidant activity of phenolic extracts from olives and olive oil has been assessed by scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and by studying the effects on the stability of stripped olive oil in the absence and presence of ferric chloride. The olive extracts contained a much higher concentration (1940,5800,mg,kg,1) of phenolic components than the olive oil extract (180,mg,kg,1). Some olive extracts were more effective than the olive oil extract in scavenging DPPH radicals, but the three varieties of olives examined showed relatively large differences in both polyphenol concentration and antioxidant activity of extracts. ,-Tocopherol and extracts from both olives and olive oil were effective antioxidants in stripped olive oil at 60,°C. Ferric chloride reduced the stability of stripped olive oil, but the olive extract studied was significantly more effective as an antioxidant in the presence of the metal salt than the olive oil extract or ,-tocopherol. Ferric ions catalysed the oxidation of caffeic acid, oleuropein and phenolic components of the olive and olive oil extracts in aqueous solution (pH 5.4). The olive extract oxidised more rapidly than the olive oil extract in aqueous solution. © 2001 Society of Chemical Industry [source] | ||||||||||