G Oil (g + oil)

Distribution by Scientific Domains


Selected Abstracts


Policosanol characterization and accumulation during ripening of Tunisian Olea europaea,L. fruits

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 3 2010
Faouzi Sakouhi
Abstract Policosanol is a mixture of bioactive molecules shown to have beneficial effects in treating hypercholesterolemia. Food products enriched in policosanol are currently available in the US market. In the present study, eight policosanol components were identified by GC-MS during the ripening of Meski olives. The quantitative characterization of these compounds was performed using GC-FID. The results showed that the maximum level of total policosanol components (947.20,mg/100,g oil) was reached at the 26th week after the flowering date of Meski olives. Hexacosanol and tetracosanol were the predominant policosanol components at Meski olive maturity. However pentacosanol, heptacosanol and tricosanol were less present in the olives and they accounted for 14% of the total policosanol at complete maturity of the fruit. The total policosanol content of Meski olives was higher than that of beeswax and whole sugar cane, which belong to the sources of dietary supplements containing policosanol. These findings indicate that olive is a potential source of these health-enhancing compounds for functional foods and nutraceutical applications. [source]


Determination of tocopherols and phytosterols in sunflower seeds by NIR spectrometry

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 5 2007
Alicia Ayerdi Gotor
Abstract The objective of this work was to develop a near-infrared reflectance spectrometry (NIRS) calibration estimating the tocopherol and phytosterol contents in sunflower seeds. Approximately 1000 samples of grinded sunflower kernels were scanned by NIRS at 2-nm intervals from 400 to 2500,nm. For each sample, standard measurements of tocopherol and phytosterol contents were performed. The total tocopherol content was obtained by high-performance liquid chromatography coupled with a fluorescence detector, while the total phytosterol content was assessed by gas chromatography. For tocopherol, the calibration data set ranged from 175 to 1005,mg/kg oil (mean value around 510,±,140,mg/kg oil), whereas for the phytosterol content, the calibration data set ranged from 180 to 470,mg/100,g oil (mean value of 320,±,50,mg/100,g oil). The NIRS calibration showed a relatively good correlation (R2,=,0.64) between predicted by NIRS and real values for the total tocopherol content but a poor correlation for the total phytosterol content (R2,=,0.27). These results indicate that NIRS could be useful to classify samples with high and low tocopherol content. In contrast, the estimation of phytosterol contents by NIRS needs further investigation. Moreover, in this study, calibration was obtained by a modified partial least-squares method; the use of other mathematical treatments can be suitable, particularly for total phytosterol content estimation. [source]


Natural Antioxidants Preserve the Lipid Oxidative Stability of Minimally Processed Avocado Purée

JOURNAL OF FOOD SCIENCE, Issue 5 2005
Pedro Elez-Martinez
ABSTRACT: Lipid oxidation is one of the major phenomena that limit the shelf-life of avocado products. The effects of adding 100 ppma-tocopherol, 200 ppm ascorbic acid, and 200 ppm ethylenediaminetetraacetic acid (EDTA) on he stability of the lipidic fraction of minimally processed avocado purées were evaluated throughout storage. , tocopherol, followed by ascorbic acid, reduced oil rancidity processes during storage. Peroxide formation was minimal when a-tocopherol was added to avocado pulp, prolonging the induction stage of oils for at least 12 wk. When preserved in vacuum, iodine and specific extinction coefficient at 270 nm (k270) values were more stable, with changes of 5.87 g I2/100 g oil and 0.237, respectively, during 24 wk. On the other hand, EDTA was not shown to be effective in preserving the stability of the lipid fraction of avocado preserved by combined methods. [source]


Extraction of Poppy Seed Oil Using Supercritical CO2

JOURNAL OF FOOD SCIENCE, Issue 2 2003
B. Bozan
ABSTRACT: Extraction of poppy seed oil with supercritical carbon dioxide (SC-CO2) was performed and the effect of extraction conditions on oil solubility and yield as well as oil composition was evaluated. Within the temperature (50 to 70 °C) and pressure (21 to 55 MPa) ranges studied, 55 MPa/70 °C gave the highest oil solubility (24.1 mg oil/g CO2) and oil yield (38.7 g oil/100g seed). Fatty acid composition of the oil obtained with SC-CO2 at 55 MPa/70 °C was similar to that of petroleum ether-extracted oil (p > 0.05) with linoleic acid making up 69.0 to 73.7% of fatty acids. Tocol content of the SC-CO2 -extracted oils varied from 22.37 to 33.35 mg/100 g oil, which was higher than that of petroleum ether-extracted oil (15.28 mg/100 g oil). Poppy seed oil may have potential in the rapidly growing specialty oil market. [source]


Chemical composition and nutritive value of peach palm (Bactris gasipaes Kunth) in rats

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2005
Pascal Leterme
Abstract The peach palm (Bactris gasipaes Kunth) is the starchy fruit of a palm tree widely cultivated in Central and South America. The present study aimed at determining its chemical composition and its nutritive value in rats. The average chemical composition of 17 samples was as follows: 410 g kg,1 water and, in g kg,1 of dry matter (DM), 54 g crude protein, 114 g oil, 39 g neutral detergent fibre, 716 g starch, 21 g sugars and 18 g ash. The main variability was observed for the oil (60,180 g kg,1 DM) and starch (590,780 g DM) contents. The proteins contained, on average, in g kg,1 of proteins, 49 g lysine, 13 g methionine, 19 g cysteine, 39 g threonine and 7 g tryptophan. The mineral fraction contained, per kg DM: 1.0 g Ca, 0.8 g P, 0.6 g Mg, 0.3 g Na, 44 mg Fe, 4 mg Cu and 10 mg Zn. The digestibility of four peach palm genotypes was determined in rats fed a diet composed of 350 g kg,1 of peach palm and 650 g of a control diet based on maize and soybean meal. The digestibility of DM, energy, starch and protein of peach palm alone reached, on average 91, 87, 96 and 95%, respectively. No difference was observed between varieties, except for starch (p < 0.05). On average, peach palm contained 51 g of truly digestible protein kg,1 DM and 3.691 kcal digestible energy kg,1 DM. A growth trial was also carried out for 1 month on rats (initial weight: 78 g) fed a diet containing 0, 200, 400, 600 or 800 g peach palm kg,1, at the expense of a diet composed of maize starch and casein. The growth rate of the rats decreased (p < 0.05) as the peach palm concentration increased. The growth decrease was due to a decrease (p < 0.05) in DM intake and to the lower quality of the peach palm protein. It is concluded that peach palm is mainly an energy source for humans and animals. It is poor in protein and minerals but can be consumed in large amounts. Copyright © 2005 Society of Chemical Industry [source]