Feel the crunch
The maker of KeepFresh claims that by absorbing ethylene, a gas which promotes ripening, its little refrigerator cartridge can extend the life of the produce in your fridge by up to six weeks. At CHOICE we've put this claim to the test and our findings are anything but black and white. Here's what we learned.
The big problem of food waste
Australians throw away $8 billion worth of spoiled food every year. In NSW alone, spoiled food such as fruit and vegies costs each household on average $1000 a year. Unless you subsist on canned food, anything you can do to reduce spoilage makes both financial and environmental sense. (And if you do only eat canned food then you should at least try a vegetable – it won't kill you. Unless it's gone off).
So, why do your fruit and vegies start to go off after a short time? It’s because of ethylene, a naturally occurring gas given off by certain fruits and vegetables that accelerates ripening in ethylene-sensitive produce. Not all produce gives off ethylene and not all produce is sensitive to it. For example, apples and pears give off ethylene and are ethylene-sensitive. Nectarines produces ethylene but aren't affected, and mushrooms are ethylene-sensitive but don't produce it.
Ethylene isn't harmful, it just makes some produce ripen faster. It's even used by the major grocery chains to bring unripe produce (which is easier to transport and store) to sellable conditions faster.
Is this the fountain of youth for your fruit?
The makers of KeepFresh, a product aimed at saving some of those fruits and vegies from the bin or compost, claims that absorbing ethylene in your fridge extends the lifespan of produce by up to six weeks.
KeepFresh works in a similar way to the moisture absorber in your wardrobe or the desiccant packet in your vitamins, but instead of absorbing moisture it absorbs ethylene gas. It's easy to use – there's no batteries or moving parts. Just throw the green plastic cartridge with its replaceable ethylene-absorbent sachet into your crisper and that's it.
Sachets need replacing every three months but they're pretty cheap – $22 gets you the cartridge together with four packets, or a 12-month supply. Compare this with how much you stand to save by reducing food waste and it starts to look like a very good idea.
I keep forgetting I've forgotten about you
If food's going off in your crisper because you forget it's there, then you may also forget to replace the KeepFresh cartridge. But it comes with a handy reminder fridge magnet, and the company also offers an email service to give your memory that extra jog.
Testing KeepFresh claims
We divided a mixture of fruits and vegetables into fridge crisper draws. There were two control groups containing only ethylene-sensitive items, and two test groups with both ethylene-producing and -sensitive items, one of which also contained a KeepFresh.
We monitored our fruit and vegetables regularly for 25 days, when we made a final inspection.
We found that after one week – roughly how long the average household stores produce – there was no difference. However, by day 25 it was a different story – all the groups were showing their age but there was a noticeable difference in the produce in the fridge that contained the KeepFresh, with the ethylene-sensitive fruits and vegetables in better shape than the control group in the other fridge. Different types of fruit and vegetables also fared differently, which is what you'd expect.
Did KeepFresh do what it said it would? Well, yes. Though it's worth keeping in mind that if you're using fresh produce soon after you've bought it (and you should – fruit and vegetables lose nutrients over time) then you won't notice a difference – it's only when your ethylene-sensitive produce is reaching advanced age that Keep Fresh makes a difference.
Also, KeepFresh won't protect produce from drying out or mould, and it's no substitute for proper food storage – any greengrocer worth their watercress will tell you tomatoes belong in your fruit bowl not your fridge because the cold can leave them flavourless and soggy, and keeping your (highly ethylene sensitive) basil in the fridge will turn it black in only a couple of days – keep it in a jar of water on your bench like you would for fresh cut flowers.
Check out CHOICE's tips for keeping your fruit and veg fresh.
So KeepFresh may extend your food's theoretical maximum lifespan but it's hardly a panacea for perishable produce. But if you take lettuce to the limit, forget to clear your crisper or just lust for longer lasting legumes, then for $22 it may be worth throwing one in your crisper.
Price: $22 for the cartridge and a 12 month supply. $3.95–$6.95 for a single refill sachet