Time to take food waste seriously
The Prime Minister has asked chief science adviser Professor Dame Juliet Gerrard to investigate food waste. It is estimated that this amounts to a pretty shocking 30% of all food that is produced, and is a major contributor to global warming and environmental harm.
Households are responsible for a significant proportion of our food waste, binning more than 10% of their weekly food spend each week. The biggest category by weight is bread – 27%.
In 2014-15, some hardy researchers from University of Otago, WasteMINZ and councils picked through a fair sample of unsuspecting rubbish bags to see what was still edible, and weighed and categorised it. A Rabobank survey reports household food waste has increased since then and the estimated value of food waste per household has risen to $1520 a year.
From a food safety angle, wasting bread seems totally unnecessary. It keeps very well in the freezer for up to three months, six at a stretch.
Outside the freezer, it can quickly develop mould in warm and humid weather, especially if it is sliced and in a plastic bag, in which case food safety expert Professor Phil Bremer says to chuck it without hesitation.
The secret is to freeze sliced bread as soon as it is purchased. Whole deli loaves can be more problematic.
Professor Sheila Skeaff studies nutrients lost in wasted food. She says it may surprise people to know the real value of what they are throwing away when they toss their bread to the birds or worse, put it in the rubbish.
The last NZ Adult Nutrition Survey in 2008-09 showed that bread, as a food group, tops the list as a source of protein (11%), as well as carbohydrates, selenium, iodine, and folate – the last two ingredients are especially important for pregnant women. These nutrients are fully conserved in the freezer.
Bremer says there’s no reason why any food should be wasted in the home unless the cat has had a go at it, or it has been exposed to some contaminant.
All food, raw or cooked, will last until its ‘‘use-by date’’ and generally for some time after its ‘‘best-before date’’ if properly stored. Fridge temperatures stall the growth of microorganisms; freezing stops their growth, but does not kill them.
Rice (number 8 on the most wasted list), if covered and refrigerated immediately after cooking, will keep for four days. Cooked rice can be frozen quite successfully and fried rice is a great way of using leftovers.
Regardless of best-by date, pasteurised milk (assuming it has been kept refrigerated) is drinkable and completely safe until it starts to smell or look strange. You can freeze milk too (take some out of the bottle otherwise the top may blow off).
It is worth investing in a range of good containers and freezer bags, and a marker pen for labelling so the freezer doesn’t fill with UFOs – unidentified frozen objects.
Reusable plastic containers are still indispensable, and justifiable for freezing and storing food, so don’t take your anti-plastic activism to counterproductive extremes.
The Love Food, Hate Waste website has everything you need to know, including specific instructions on how to store different vegetables. Domestic science and its practitioners have for too long been undervalued.
There’s every incentive now to take food waste very seriously. It can make or break a household, as well as carbon emissions and budgets.