Changes of Headspace Volatile Constituents of Palm Olein And Selected Oils after Frying French Fries
Titel:
Changes of Headspace Volatile Constituents of Palm Olein And Selected Oils after Frying French Fries
Auteur:
Muhammad Nor Bin Omar Nor Nazuha M. Nor Nor Aini Idris
Verschenen in:
Pakistan journal of biological sciences
Paginering:
Jaargang 10 (2007) nr. 7 pagina's 1044-1049
Jaar:
2007
Inhoud:
Abstract:</b> Changes of aroma constituents of palm olein and selected oils after frying French fries have been studied. The aroma constituents of used oils were collected using a solid-phase microextraction (SPME) headspace technique with an absorbent of a divinylbenzene/carboxen (DVB/CAR) (50/30 μm) on polydimethylsiloxane (PDMS) fibre. The extracted volatiles were desorbed from the fibre in the injection port of the gas chromatograph at 250°C and the aroma constituents were identified by GC-MS. Analytical data showed that volatile constituents of palm olein, soybean oil, corn oil and sunflower oil changed while frying continued from 2 to 40 h, respectively. In palm olein, the 2t,4t-decadienal content decreased from 14.7 to 5.5 μg g-1 (40 h) whilst hexanal increased from 7.9 μg g-1 (2 h) to 29.2 μg g-1 (40 h), respectively. Similar result was also obtained from soybean oil after frying French fries. The 2t,4t-decadienal content decreased from 15.9 μg g-1 (2 h) to 3.2 μg g-1 after 40 h frying whilst hexanal increased from 10.2 μg g-1 (2 h) to 34.2 μg g-1 (40 h). Meanwhile, in corn oil, it was found that 2t,4t-decadienal decreased from 15.6 μg g-1 (2 h) to 3.2 μg g-1 (40 h) whilst hexanal increased from 11.3 μg g-1 (2 h) to 33.8 μg g-1 when frying time reached 40 h. In sunflower oil, it was found that 2t,4t-decadienal, decreased from 16.8 μg g-1 (2 h) to 1.2 μg g-1 (40 h) while hexanal increased from 9.5 μg g-1 (2 h) to 32.4 μg g-1 when frying time reached 40 h. It also showed that used oils exhibited off-odour characteristics due to the increasing amount of hexanal while their freshness characteristics diminished due to the decreasing amount of 2t, 4t-decadienal.
Uitgever:
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