High linolenic oils

Roman Przybylski University of Manitoba, Winnipeg, Manitoba, Canada, Canola Oil, Flax Oil and High Linolenic Oils. 

Refined, bleached and deodorized. Adapted from Przybylski, R., 2005 Flax oil and high linolenic oils. In Shahidi, F. (Ed.), Bailey s Industrial Oil and Fat Products. John Wiley Sons, Inc., Hoboken, NJ, pp. 281 -298. ... 

High-grade oil with the essential polyunsaturated fatty acids can be extracted very successfully with CO2. The physiological activity of these oils is determined by the at-6,9-double bonds, and y-linolenic acid, Ci8 3 (6c, 9c, 12c) is of particular interest. 

A practically odourless clear oil with a faint yellow tinge. Inexpensive, thin and non-oily it is especially suitable for blending with other carriers. Extracted from the seeds, which have a long tradition in culinary applications. The oil is available in a range of qualities and is also a favourite for cooking but this is the highly refined oil, which is not usually recommended for aromatherapy. External use is believed to be beneficial for skin problems such as ulcers, bruises, acne and seborrhoea. Fatty acid composition linoleic acid (up to 74%), oleic acid (up to 15%), palmitic acid (up to 6.4%), stearic acid (4.2%), linolenic acid (0.2%) and palmitoleic acid (0.1%). It is also high in vitamins A, B-com-plex, D and E, with minerals calcium, potassium, iron, zinc and phosphorus. Considered to be a safe oil with no reported contraindications. 

Chia Salvia hispanica). Chia seeds contain 32-38% of a highly unsaturated oil (97). The fatty acid composition for five samples from Argentina have saturated acids (9-11%), oleic (7-8%), linoleic (20-21%), and linolenic acid (52-63%). 

Reported activation energy values for the thermal i-rra i-isomerization of linoleic and linolenic acid are rather low (178 kJ/mole vs. 144—148 kJ/mole, respectively) (8). This is an indication that TFAs are relatively easily formed at elevated deodorization temperature. Different studies show that the relative isomerization rate can be expressed as follows Cig 3 (100) Cig 2 (10) Cig i (1) (11-13). Consequently, oils with a high linolenic acid content, such as soybean and rapeseed oils, are most sensitive to di-fra i-isomerization during deodorization. 

The content of tocopherol, a natural antioxidant in canola, is comparable to those of peanut and palm oil. This is an important factor for oils with high linolenic acid content, which can reduce the shelf-life of the product, while the namral antioxidant, if present, can prevent oxidation during storage and processing. 

Ohhashi, K., Takahashi, T., Watanabe, S., Kobayashi, T., Okuyama, H., Hata, N., and Misawa, Y. 1998. Effect of replacing a high linoleate oil with a low linoleate, high alpha-linolenate oil, as compared with supplementing EPA or DHA, on reducing lipid mediator production in rat polymorphonuclear leukocytes. Biol. Pharm. Bull. 21, 558-564. 

There are several minor oilseeds that an important because of their special characteristics, properties, nutritional and health benefits. These include high-y-linolenic oils (evening primrose, borage or starflower and blackcurrant), virgin olive oil (Chapter 9), and the seed oils from sesame, rice bran, pumpkin, hemp and melon. This chapter deals with three minor vegetable oils, namely sesame seed oil, rice bran oil, and flaxseed (linseed and linola) oil. 

Table 11.11 Characteristics and fatty acid composition of linseed oil (high linolenic acid varieties)...

Two additional low-linolenic acid double-low rapeseed (canola) cultivars with incremental improvements in agronomic performance, Apollo (Scarth et al. 1995) and Allons (Scarth et al. 1997), were developed and released by the University of Manitoba. There was limited commercial production of these low-linolenic acid, double-low rapeseed (canola) cultivars in Canada. More recently, high-stability oil double-low rapeseed (canola) cultivars that have low linolenic acid concentrations (<3%) and high oleic acid concentrations (>70%) have been developed. These new high-oleic acid, low-linolenic acid, high-stability oil, double-low rapeseed (canola) cultivars have competitive seed yields and are commercially successful (Canola Council of Canada 2008). 

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