Lucky dip of interesting research results (Part 7)
admin | December 4, 2010Here are my interpretations of some research papers covering a variety of areas including use, health and competing products.
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After a single overheating, EVOO produced less toxic compounds than sunflower, corn or vegetable oil. EVOO also outperformed corn and sunflower oil in this regard when repeatedly heated.
Isidori and Parrella (2009) Genotoxicity of Aqueous Extract From Heated Cooking Oils and its Suppression by Lactobacilli. Food Science and Technology International, 15, 267-273.
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How do fraudsters fake EVOO? By greening up refined vegetable or seed oil using the copper salt of chlorophyll (Known as additive E141i). A test for detecting this artificial pigment is proposed.
Roca et al. (2010) Control of Olive Oil Adulteration with Copper–Chlorophyll Derivatives. J. Agric. Food Chem. 2010, 58, 51–56.
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Compared with oleuropein and hydroxytyrosol the ‘peppery’ phenolic DHPEA-EDA (better known as oleocanthal) best protected red blood cells from oxidative stress.
Paiva-Martins et al. (2010) Powerful Protective Role of 3,4-Dihydroxyphenylethanol–Elenolic Acid Dialdehyde against Erythrocyte Oxidative-Induced Hemolysis. J. Agric. Food Chem. 2010, 58, 135–140.
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The relative oxidative stability of various edible oils using the Rancimat test was determined to be: macadamia>sesame=rice bran>avocado>almond>hazelnut>grapeseed>walnut. Higher polyunsaturation contributed significantly to reduced stability. Olive oil was not included in the study.
Kochhar et al.(2009) Oxidative stability and shelf-life evaluation of selected culinary oils. International Journal of Food Sciences and Nutrition, 60, 289-296.
Comment: Extra virgin olive oil would certainly be more stable than all of these due to its low levels of polyunsaturation and antioxidant content.
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Oleic acid was incorporated into the fat structure of refined palm olein oil using immobilised lipases. The tri-oleic triacylglyceride (the most common fat found in olive oil) was increased three fold, and an overall oleic acid level of 56% was achieved.
Lin and Huey(2009) High Oleic Enhancement of Palm Olein via Enzymatic Interesterification. Journal of Oleo Science, 58, 549-555.
Comment: See the trouble that producers of other edible oils will go to to replicate olive oil.
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The median alpha-tocopherol level of 263 Italian EVOO’s was reported as 151 mg/kg and the pungent phenolic oleocanthal as 85 mg/kg.
Servilli et al. (2009) Phenolic compounds in olive oil: antioxidant, health and organoleptic activities according to their chemical structure. Inflammopharmacology 17, 76-84.