Oils ain't oils

These days, there seem to be countless options available on the supermarket shelves, so the Test Kitchen team is here to bring you the good oil on these pantry staples!

When it comes to choosing the right oil for your cooking needs, there are a few key factors to take into account. Oils vary greatly in their chemical structure and production, which in turn will influence your choice. Here’s the lowdown.

EXTRACTION PROCESSES

Cold−pressed oil, the most expensive type, is made from the first pressing of the seed, nut or fruit. No heat or chemicals are used in the process. It is best used fresh, so buy in small quantities to avoid it going rancid. Virgin or extra virgin are the terms used for oil produced by cold−pressing.

Refined oil is extracted using heat or chemicals, resulting in a relatively colourless and odourless oil with good keeping qualities.

USAGE

• Cold−pressed oils are used in salad dressings, as flavouring for cakes or breads, and for lightly frying vegetables or fish. They are also used as a condiment to drizzle over bread, cooked vegetables or hot dishes.

• Virgin oils are used for general light frying, cakes and roasting.

• Refined oils are used in general cooking, and for cakes, breads and sauces when a neutral flavour is needed.

SMOKE POINT & FLASH POINT

Every oil or fat has a smoke point (the temperature at which it begins to smoke, indicating that it is breaking down) and a flash point (the higher temperature at which it will ignite).

• Oils and fats with high smoke points are the most efficient for frying, though other considerations such as flavour or health implications also come into play when choosing a cooking oil.

• Note that every kitchen should have a fire blanket placed near to the stove. Placed over a fire, it will extinguish it immediately. They are available inexpensively at hardware shops.

• Storing a small fire extinguisher under the sink is also a good idea. Make sure to familiarise yourself with how to use it on a regular basis.

STORAGE

• Cold−pressed oils should be kept in the fridge or a cool, dark, dry place. Use within a year. Some oils will solidify when chilled. Pour or spoon out what is required – it will quickly melt and return to its liquid form, then immediately re−store the bottle. Aim to buy smaller quantities more frequently, as there is less chance of spoilage.

• Refined oils can be stored for a year or more in a tightly capped bottle in a cool, dark place.

ALL ABOUT OLIVE OIL FLAVOUR FACTS

• The highest grade is ‘extra virgin’ which is virgin oil of the highest quality with an acidity level of no more than one per cent. It is considered by experts to have the finest flavour. Like wine, the flavour of an individual olive oil depends on the variety of fruit used. Extra virgin olive oil (often seen termed as EVOO) in particular will vary considerably from strong and fruity to grassy and delicate, while some may have a pungent, bitter or peppery taste. These are all desirable, as long as they are present in moderation and harmony with other flavour components. As the oil is further processed, the flavour will become less distinct. Just below extra virgin comes ‘virgin’ oil, and then ‘pure olive oil’ (or simply ‘olive oil’), which is usually a mixture of virgin and refined oils. This will have the mildest flavour.

• It’s worth noting that olive oils labelled ‘light’ are not lower in kilojoules; they are simply light in flavour. That is, they are processed and often mixed with other oils.

HEALTH BENEFITS

• The Mediterranean diet is one of the healthiest in the world, associated with lower rates of heart disease, lower blood pressure, lower risk of stroke, better cognitive health, lower risk of diabetes and lower risks of many cancers. There

are many factors that may contribute to this, but one of the key characteristics is the use of extra virgin olive oil as a staple food and principal fat in the diet.

• Both olive oil and avocado oil are rich in monounsaturated fats. A solid body of scientific evidence supports making these fats the major ones in your diet.

• Olive oil may help you to achieve a healthier blood cholesterol profile, improve your insulin sensitivity, help to control blood glucose levels, improve a fatty liver, and even reduce the amount of fat you store around your abdomen.

BUYING GUIDE

• It is recommended you buy extra virgin olive oil and not products labelled as ‘light’, ‘pure olive oil’ or ‘pomace’. These are all refined and do not contain the health−promoting qualities of extra virgin olive oil. Refining the oil removes many of the beneficial antioxidants, phytosterols and polyphenols present in fresh, unrefined extra virgin oils.

• Oil is not like wine – it doesn’t get better with age. The fresher it is the better. Choose quality over quantity and you will reap the benefits.

• Good−quality extra virgin olive oil has a relatively high smoke point of about 190°C. Use it for stir−frying, pan−frying, barbecuing, grilling, and roasting foods in the oven. Store it in a cool, dark place to retain its freshness and its health−promoting properties. Use it regularly to ensure you are always consuming this year’s batch.

• Buy Australian olive oil if possible, as you are guaranteed the quality claimed on the label. Some imported olive oils are not always what they say they are and may often be rancid by the time they reach our shores.

• It’s always worth exploring farmers’ markets for locally produced olive oils, and thus supporting your local farmers and producers. And the flavour of a freshly pressed olive oil is definitely a pleasure worth seeking out.