Have you ever wondered how cold pressed oils are made? Do you assume that when you buy 'Cold Pressed', the seeds were actually just that and nothing else?  How are they different from the refined oils we use in the kitchen to cook food, and do they even make for a healthy alternative to cooking oils?

There is an increasing awareness of the need to include plant-derived fatty acids in any diet. In conjunction with this is an increasing desire to alleviate the symptoms of many illnesses by using natural products. These factors have led to a strong interest in the potential health benefits of plant oils, particularly cold pressed oils. Recently, many experts have agreed that cold pressed oils are a healthy alternative to refined cooking oils. They are known to be cholesterol free, are not deodorized, bleached or processed, do not contain harmful solvent residues, and contain natural antioxidants that are beneficial for the body. In addition, their natural flavour and odour is retained, enhancing your favourite recipes.

Oil extraction methods

Edible oils are extracted from seeds, fruits, vegetables and nuts. There are several methods for extracting these oils including solvent extraction and mechanical extraction.

Solvent Extraction

Most of the world’s plant oils are extracted using solvents such as hexane and benzene. It is a cost-effective method when dealing with large volumes and is very efficient at removing most of the oil from the seeds. The process leaves a crude oil that requires refining, eg. bleaching and deodorising, before it is suitable for human consumption. These refining operations strip the oil of natural antioxidants, vitamins and flavour and the finished oil may contain some residual solvents. The solvent extraction method is used to produce most common cooking oils found in supermarkets, and as far as frying is concerned, refined oils have an advantage over cold pressed oils.

Cold Pressing

Cold pressing is a form of ‘expeller pressing’, which is a mechanical extraction method. Expeller pressing crushes the seed, forcing out the oil through pressure, but beware … all expeller methods are not equal! Some expeller methods require the seed to be dried, de-hulled, cracked and even heated. Using heat extracts more oil from the seed, but heat can degrade the oil’s flavour and nutritional quality.

True ‘cold pressing’ is unique in that it is environmentally friendly and does not use heat or chemicals during the production process. The temperature during the production process is also strictly controlled. Cold pressed oils therefore retain the nutritional properties and health benefits that would otherwise be damaged by being exposed to heat. They also contain valuable bio-active substances that are not present in refined oils.

True cold pressed oils are:

  • typically rich in vitamin E, which has anti-inflammatory and healing properties.
  • rich sources of monounsaturated and polyunsaturated fatty acids – these healthy fats tend to degrade when exposed to heat, the sole reason why they are not extracted through heating techniques.
  • rich sources of natural antioxidants such as tocopherols and phenolic compounds. Antioxidants help combat free radicals that cause cell damage in the body, and also boost your immune system.
  • Natural - just as nature intended.

Origin matters

Depending on the country of origin, there are also strict temperature requirements for cold pressed oils.

For example, in the US, ‘cold pressed’ specifically requires the entire process to occur at 49°C or less, and to meet the standards of the British Association of Cold Pressed Oil Producers (BACPOP) cold pressed oils must be produced at 40°C or lower. The BACPOP standard is the one we at Totally Kiwi adopt; our processing techniques have been perfected over the last 30 years to ensure our oils are produced at below 40°C.

So when you buy imported cold pressed oils, be aware that these oils may be cold pressed at slightly different temperatures. Oils known as pressed or expeller pressed are generally those that are produced using expellers that don’t meet these strict temperature requirements.