Search results for "Free acid"
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High quality extra virgin olive oil from olives attacked by the olive fruit fly, Bactrocera oleae (Rossi) (Diptera Tephritidae): which is the tolerab…
2017
The infestation due to the olive fruit fly, Bactrocera oleae (Rossi), the key pest in most of world olive groves, has been monitored in six years, from 2004 to 2008 and in 2014, in eight coastal Sicilian olive groves consisting of ‘Cerasuola’ and ‘Nocellara del Belice’ cultivars. Infestation was recorded following the classical sampling method based on olive collection and dissection, in order to count live olive fruit fly instars (eggs, larvae and pupae) and exit holes. Four different infestation indexes, all of them calculated using data recorded at harvest, have been used to assess their relationship with the main three quality parameters of the olive oil obtained from the same olive sam…
Simultaneous gas chromatographic determination of aliphatic C2−C20 n-carboxylic acids and their methyl esters using SE-30 and OV-351 quartz capillary…
1983
Simultaneous determination of aliphatic C2−C20 carboxylic acids and their methyl esters was carried out using SE-30 and OV-351 quartz capillary columns with temperature programming. Complete resolution of all 36 components was achieved. On SE-30 the methyl ester and the corresponding free acid are eluted in turn, whereas on OV-351 acetic acid eluted after methyl octanoate, after which the Cn methyl ester and Cn-6 carboxylic acid (n>9) are eluted one after the other. A non-polar SE-30 column is better for long-chain acids giving sharp peaks without tailing, the analysis time of the mixture being less than 16 minutes. The weight response correction factors for compounds under optimum operatin…