Olive oil: liquid gold

olive oil

This Mediterranean food staple is full of healthy fatty acids and antioxidants with a myriad of benefits on a number of health conditions. Olive oil is made by crushing olives and putting them through a press to squeeze out the oil. The crushed olives can be pressed numerous times. the first pressing creates what is known as extra virgin olive oil. Extra virgin olive oil is the preferred oil to be consumed as it has the most amount of powerful antioxidants and anti-inflammatory compounds called polyphenols. Olive oil is primarily made up of monosaturated fats, one of which is called oelic acid. Olive oil also contains vitamin E, beta carotene and squalene, an important antioxidant that is great for skin health. The antioxidant and anti-inflammatory actions of olive oil mean that it can positively affect conditions such as heart disease, obesity, type 2 diabetes, dementia and cancer. The oleic acid in olive oil also helps to raise the 'good' cholesterol know as HDL and the polyphenols produce positive effect on gut bacteria balance.

To gain the benefits of consuming olive oil, aim for 1-2 tablespoons of extra olive oil per day. You can use it in salads, steammed vegetables, dips, marinades, cooked meals and even smooothies.

To keep your olive oil at its freshest make sure to store it away from light, air and heat. Opt for extra virgin olive oil sold in dark bottles and look for those with a rich green colour. Be sure to read the lables and check that it is 100 percent extra virgin olive oil as some brands  use refined and unrefined olive oils. 'Cold Pressed' olive oil means that very little heat was used to extract the oil from the olives. This allows for more of the nutrients to be preserved.

There is some debate on whether olive oil has the same benefits when heated to a certain temperature. During the cooking process, fatty acids can react with oxygen and become damaged. However, unlike a number of other oils, olive oil is quite resistant to high heat due to its polyphenol and tocopherol content, with studies suggesting that heating extra virgin olive oil up to 180 degrees celcius is safe both in terms of oxidation and its nutritional value.

 

There are many ways to enjoy olive oil other than in pasta dishes or as a dip or salad dressing. Why not give this delicious cake recipe a try:

Pistachio, cardamom and olive oil cake

Moist, fragrant and very green, this cake is perfect with a dollop of loosely whipped cream.

Serves 8
200g shelled pistachios
8 cardamom pods
100g polenta
1 tsp bicarbonate of soda
50g butter
175ml extra virgin olive oil
3 medium eggs, at room temperature
200g rapadura sugar
1 unwaxed lemon

1 Preheat the oven to 170C/340F/gas mark 3-4. Grease and line a 23cm round baking tin. Place the pistachios on a dry baking tray and toast in the oven for 3 minutes until they have a greasy shine and a nutty aroma. Remove and set aside to cool.

Bash the cardamom pods using a pestle and mortar, discard the husks, and grind the seeds to a fine powder.

Tip the pistachios and cardamom powder into a food processor and pulse until they're finely ground. Pour the pistachios into a large bowl with the polenta and bicarbonate of soda and mix until evenly combined.

Place the butter and olive oil into a small pan on a low heat until the butter has melted but not boiled. Leave to cool slightly.

5 In a second large bowl, whisk the eggs and sugar together until light, fluffy and thick enough to slowly fall off the whisk. Very slowly trickle in the butter and oil, slowly whisking it into the eggs until fully incorporated, then gently fold through the nut and polenta mixture. Zest the lemon, then halve and add the juice and zest to the mix. Stir to combine.

6 Pour into the greased tin and bake for 45-50 minutes. Check that a skewer comes out clean and the surface springs back a little when you press in the centre. The cake will have risen with a golden top, but don't be upset if the middle has collapsed slightly or even cracked.

7 Rest in the tin until cool, and serve in thick slices with a dollop of cream. This cake is so moist that it actually improves the flavour to keep for a day or two. However, its vibrant green colour will start to fade.

 

References

Akl, M.R., Ayoub, N.M., Mohyeldin, M.M., Busnena, B.A., Foudah, A.I., Liu, Y.Y. and Sayed, K.A.E., 2014. Olive phenolics as c-Met inhibitors:(-)-oleocanthal attenuates cell proliferation, invasiveness, and tumor growth in breast cancer models. PloS one9(5), p.e97622.

Allouche, Y., Jiménez, A., Gaforio, J.J., Uceda, M. and Beltrán, G., 2007. How heating affects extra virgin olive oil quality indexes and chemical composition. Journal of agricultural and food chemistry55(23), pp.9646-9654.

Berr, C., Portet, F., Carriere, I., Akbaraly, T.N., Feart, C., Gourlet, V., Combe, N., Barberger-Gateau, P. and Ritchie, K., 2009. Olive oil and cognition: results from the three-city study. Dementia and geriatric cognitive disorders,28(4), pp.357-364.

Casal, S., Malheiro, R., Sendas, A., Oliveira, B.P. and Pereira, J.A., 2010. Olive oil stability under deep-frying conditions. Food and chemical toxicology,48(10), pp.2972-2979.

Castañer, O., Fitó, M., López-Sabater, M.C., Poulsen, H.E., Nyyssönen, K., Schröder, H., Salonen, J.T., De la Torre-Carbot, K., Zunft, H.F., De la Torre, R. and Bäumler, H., 2011. The effect of olive oil polyphenols on antibodies against oxidized LDL. A randomized clinical trial. Clinical Nutrition30(4), pp.490-493.

Covas, M.I., Nyyssönen, K., Poulsen, H.E., Kaikkonen, J., Zunft, H.J.F., Kiesewetter, H., Gaddi, A., de la Torre, R., Mursu, J., Baumler, H. and Nascetti, S., 2006. The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial. Annals of internal medicine145(5), pp.333-341.

Romero, C., Medina, E., Vargas, J., Brenes, M. and De Castro, A., 2007. In vitro activity of olive oil polyphenols against Helicobacter pylori. Journal of agricultural and food chemistry55(3), pp.680-686.

Torres, N., Guevara-Cruz, M., Velázquez-Villegas, L.A. and Tovar, A.R., 2015. Nutrition and atherosclerosis. Archives of medical research46(5), pp.408-426.