4 Low-tech Food Hacks to Make the Most of Your Food

You don’t always need fancy gadgets to make some kitchen chemistry. Here are four low-tech food hacks that take advantage of things you already own, with some basic science, to improve your food.

1. Chill your onion to prevent tears

When you cut into an onion, its sulphur compounds react with an enzyme to cause the release of a chemical called propanethial S-oxide, an irritant that makes your eyes water.¹ You could go down the tried and tested route of wearing swimming goggles to stop this compound from reaching your eyes as you slice your onions – but there is another way.

Before you chop your onion, put your onion in the fridge. This slows the release of propanethial S-oxide, helping your eyes stay tear-free. The US National Onion Association recommends 30 minutes of chilling in the fridge before you dice, but putting it in the freezer for just a few minutes would probably do the trick, too.²

Before long, there may even be another solution to keep the tears from running: tear-free onions. In 2002, scientists discovered exactly which enzyme was needed to produce the offending propanethial S-oxide.³ Then, in 2015, researchers in Japan announced that they’d made an onion with drastically reduced levels of this enzyme.⁴ But, only time will tell if it will ever make it to market.

Editor's Update: As of 2023, tearless onions are on the market! In Australia, Woolworths are selling bags of "Happy Chop" onions, which reportedly cost 50% more than the regulars. Apparently, they don't taste of much, but we haven't got our hands on one yet.

2. Use salt in coffee to make it less bitter

Lots of people swear by adding a tiny pinch of salt to coffee that would otherwise be too bitter to drink.

In 1997, researchers tested this idea by mixing a solution containing a bitter-tasting chemical with salt and getting volunteers to judge how bitter it tasted. People rated the solutions containing salt as being less bitter, when in reality, they had the same amount of the bitter chemical as the samples without salt. The scientists concluded that salt selectively filters out the taste of bitterness and so enhances other flavours, like sweetness.⁵

But be warned: some people who’ve tried this trick think it just makes their coffee taste more salty.⁶ So try it with a smaller amount of coffee before wasting a whole cup – unless you were going to throw it out anyway.

3. How to stop avocado from turning brown

Once you make fresh guacamole, it’s only a matter of time before your lovely avocado-green dip turns brown. This is because of a process called enzymatic browning.⁷

Compounds in avocado known as phenols (micronutrients often found in plant-based foods) react with enzymes and oxygen to start the browning process. This leads to the production of melanin, which makes that unappetising brown layer form on top.

But all is not lost. If you can stop the oxygen from reaching the dip, you can stop the reaction from happening. One way to do this is by putting a layer of cling film over the top of the bowl, making sure it’s in contact with your food to stop any oxygen from getting in. Or alternatively, use beeswax paper—anything that keeps the oxygen from leaking in works, too! A more eco-friendly method is to use a layer of water on the top, which you can pour away before you serve the guacamole.

4. How to ripen tomatoes

Have some fruit that you want to eat, but it’s just not ripe enough yet? Add a banana to your fruit bowl, and just wait.

Most fruits produce ethylene gas (a plant hormone) when they start ripening to help regulate the ripening process. Different types of fruit release this gas in differing amounts. McIntosh apples, for example, produce a lot of ethylene, making them hard to store for long times as they become too soft and overripe.⁸

Luckily, you can use this to your advantage. Bananas also produce a lot of ethylene, so you can give other slower-to-ripe fruits, like tomatoes, a helping hand by storing them together. The ethylene from the banana should help ripen the tomatoes quicker than if it were left to its own devices.

And if you need to ripen a banana, you can just keep it in a paper bag to trap the ethylene gas near to it, to speed up the process.⁹

In industry, both ethylene and acetylene are used to ripen fruits precisely to make sure they’re at the right level of ripeness when they reach consumers.¹⁰