Sunflower tocopherol content

Minor constituents tocopherols and phytosterols. Vegetable oUs are the primary source of tocopherols in the average diet. Canola oil is a relatively rich source of tocopherols (refer to Table 6) it is similar in total tocopherol content to com oil, cottonseed oU, safflower oil, and sunflower oil (60-70 mg/100 g). Only soybean... 

Deodorization There are no major differences between deodorization procedures for sunflower oil and other vegetable oils. The loss of tocopherols in the oil is worth noting for sunflower oil, though. The average tocopherol content of sunflower oil is medium (440-1520 ppm, according to Codex-Stan 210-1999), nearly all of which is alpha-tocopherol (403-935 ppm). Table 18 shows the reduction in the tocopherol content upon deodorization of sunflower oil (69). Tocopherols may be recovered from the distillate of deodorization. 

TABLE 18. Total Tocopherol Content (ppm) of Sunflower Oil In Different Refining Stages [Based on (69)]. 

That tocopherols are apparently nature s choice of antioxidant is demonstrated in Fig. 4, which is similar to a correlation observed by Hove and Harris (1951). Here the total tocopherol content of oils from babasu (1), beechnut (2), carrot (3), castor bean (4), cacao (5, 6), coconut (7, 8), corn (9, 10), cottonseed (11-13), hazelnut (I4, 15), linseed (16), oat germ (17), okra seed (18, 19), olive (20-25), palm (26-28), peanut (29-33), pecan (34, 35), poppyseed (36), rapeseed (37), rice bran (38), safflower (39), sesame (40, 4I), soybean (42-44), sunflower (45), and wheat germ (46-50), as reported by Lange (1950), have been plotted against their total linoleic plus linolenic acid content as reported by Hilditch (1956). The linoleic, plus linolenic acid content of oils from the same species varies, sometimes threefold. It is unfortunate that the content of tocopherol, linoleic acid, and linolenic acid have seldom been determined on the same sample. If Fig. 4 could have been prepared from such data, the correlation would probably be even more dramatic. 

Alpaslan, M., Tepe, S. and Simsek, O. Effect of refining processes on the total and individual tocopherol content in sunflower oil. International J. Food Sci. Technol. 36, 737-739 (2001). 

The saponifiable portion of the fatty oil accounts for about 90% of the total fixed oil and is characterized by a very high content of octadecenoic acids. Petroselinic and oleic acid occur at similar levels and jointly comprise 74-85%, linoleic 7-16% and palmitic 4-8%, of the constituent fatty acids. During prolonged storage of the spice, the free fatty acid content gradually increases and this is a good indicator of the age of the material. The contents of fatty acids, sterols and total tocopherols in a deodorized oil derived from coriander seeds (yield up to 28%) are compared with those in sunflower oil and tests on the biological effects of coriander oil are reported by Mironova et al. (1991). Of the fatty acids present, total C18 1 acids (petroselinic acid + oleinic acids) constituted 80—82% and petroselinic acid alone 50—60%, and the food value was lower than that of sunflower oif. Kim et al. (1996) found the production of petroselinic acid from cell suspension cultures of C. Sativum. 

Flaxseed oils contain much lower amounts of tocopherols, half of the amount present in sunflower and canola oils and one-third of that present in soybean oil (Table 2). A lower content of these antioxidants makes these oils even more susceptible to oxidation. Gamma-tocopherol was found as the main tocopherol in flax oils, with a contribution of about 80% to the total amount. This makes flax oil comparable with soybean oil. Among unique antioxidants detected in flax oils was plasto-chromanol-8. This compound is a derivative of gamma tocotrienol with twice as long unsaturated side chain. Plastochromanol-8 was found to be a more efficient antioxidant than any tocopherols isomer (15). A low content of tocopherols in flaxseed did not make them more susceptible to oxidation experiments showed that milled flaxseed could be stored for 28 months at ambient temperatures without measurable changes in oxidation products. This can be attributed to the presence of antioxidants other than tocopherols in the seeds (16). 

Composition and content of tocopherols in camelina oil was similar to perilla oil, where more than 80% of all tocopherols were gamma isomer (Table 4). Alpha and delta tocopherols were detected as minor antioxidants (77). The total content of tocopherols was comparable with perilla oil, and higher than that in flax oil (Tables 4 and 2). The total content of tocopherols in camelina oil is higher than canola, flax, soybean, and sunflower. 

Other Components of the Unsaponifiable Matter The unsaponifiable matter in a cmde regular sunflower oil is usually in the range of 0.5-1.5% (9, 17), or lower than 15 g/kg according to the Codex-Stan 210-1999. In addition to sterols (around 2.4. 6 g/kg) and tocopherols and tocotrienols (0.4-1.5 g/kg), there are minor components of sunflower oil. Aliphatic compounds and terpenoids occur naturally in oils. Of the terpenoid family, squalene is the most widely occurring compound. The occurrence of squalene in regular sunflower oil is fairly low 0.008-0.019% (5) or 15-20 mg/100 g (9). The aliphatic alcohol content is 100-mg/lOO-g oil (9). 

The unsaponifiable matter of soy, corn, canola/rapeseed, sunflower, cottonseed, peanut, and palm ranges from 10-30%, and it is composed of 40% phytosterols and 15% tocopherols (199-202). The temperature, duration, quantity of skimming vapor, and the extent of vacuum used for deodorization are the parameters that greatly influence the quality and quantity of DOD. The low content of tocopherols and sterols in the DOD often requires a concentration step however, if the starting material is soybean, this is not an issue because of the high concentration of these compounds. 

Comparisons of the tocopherol and sterol contents from various oils indicate that some oils have appreciably higher contents of specific tocopherols and sterols (94). For example, sunflower is high in a-tocopherol, whereas soybean is higher in y-tocopherol. As deodorization strips tocopherols and sterols from the oil, different feedstock oils yield different concentrations and types of tocopherols. 

Consequently, oils rich in a-tocopherol (sunflower seed, cottonseed oil) in particular have a high Vitamin E content. 

Good sources of vitamin E are vegetable oils, such as com, soy, and peanut oii. Animal fats, such as butter and lard, contain lowrer amounts of the vitamin. The content of the most important form of vitamin E, a-tocopherol, in various foods is as follows. Com oil contains about 16 mg of a-tocopherol per 100 g sunflower oil 50 mg/100 g, wheat germ oil 120 mg/100 g and fish, eggs, and beef 0.5 to 2,0 rng/100 g. In plants, a-tocopherol resides in chloroplasts, while other forms of tocopherol ( i-, y-, and 5-tocopherol) occur elsewhere in the plant cell. Tocotrienols, which also have vitamin E activity, are not found in the green parts of plants, but in the bran and germ of seeds... 

Details of the tocopherol components are shown in Table 5.11 (Muller-Mulot 1976) and of the sterols and sterol esters in Table 5.12 (Popov et al. 1975). Values for other typical vegetable oils, such as soybean and corn, are included for comparison. Both soybean and corn oils have higher levels of y-and 8-tocopherol than sunflower oil. There is some difference between the sterol contents of the three oils, but the sterol ester content of com oil is much higher than in either sunflower or soybean oils. 

Estimation of true vitamin E in foods requires quantitative determination of all its components since they vary in their biological potency. This vitamin consists of four tocopherols (a, jS, y, and 6) and four tocotrienols (a, jS, y, and d), but the three major constituents responsible for vitamin E activity are the a-, jS-, and y-tocopherols. While these compounds are fluorescent, their esters must be reduced to free alcohols for total tocopherol assays. Total vitamin E can be directly obtained through fluorimetry, but the determination of individual components is carried out using LC with fluorimetric detection. This procedure has been used to determine the composition of vitamin E in seed oils from maize, olives, soya beans, sesame, safflower, and sunflower by measuring the content of all the four tocopherols plus a-tocotrienol. The simultaneous determination of tocopherols, carotenes, and retinol in cheese has been carried out using LC with two programmable detectors coimected in series, a spectrophotometer and a fluorimeter. Carotenes have been determined photometrically, and fluorimetric measurements have been obtained for tocopherol and retinol. 

Aladedunye, F Przybylski, R. Frying stability of high oleic sunflower oils as affected by composition of tocopherol isomers and linoleic acid content. Food Chemistry, 2013, v. 141 (3), 2373-2378. 

About 60-70% of the tocopherols in oilseeds are retained during the oil extraction and refining process (cf. 14.4.1 and Table 3.54). Some oils with very similar fatty acid compositions can be distinguished by their distinct tocopherol spectrum. To illustrate this, two examples are provided. The amount of P-tocopherol in wheat germ oil is quite high (Table 3.54), hence it serves as an indicator of that oil. The blending of soya oil with sunflower oil is detectable by an increase in the content of linolenic acid (cf. 14.5.2.3). However, it is possible to make a final conclusive decision about the presence and quantity of soya oil in sunflower oil only after an analysis of the composition of the tocopherols. 

Gotor et ah (2007) reported the use of near-infrared reflectance spectrometry (NIRS) to predict the contents of tocopherol and phytosterol in sunflower seeds. About 1000 samples of ground 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 made. The total tocopherol and phytosterol contents were assessed by FIPLC with a FL detector and GC, respectively. The calibration data set for tocopherol and phytosterol ranged from 175 to 1005 mg/kg oil (mean value around 510 140 mg/kg oil) and from 180 to 470 mg/100 g oil (mean value 320 50 mg 100/g oil), with values of 0.64 and 0.27, respectively. In this study, calibrations were obtained by a modified PLS method. 

Oils that have undergone lipid peroxidation may have adverse physiological effects if consumed. Eor example, Eder (1999) found that oxidized oils in a diet could diminish the ability of rat heart and liver tissues to desaturate fatty acids. Work by Sheehy et al. in 1994 showed that the consumption of thermally oxidized sunflower oil by chicks reduces the tissue content of a-tocopherol and increases the susceptibility of tissues to lipid peroxidation. The addition of vitamin E to refined olive oil increases the stability of the oil under pro-oxidant conditions and decreases the oxidative damage caused by adriamycin in rats (Quiles et al., 1999). 

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