How do I prep vegetables in advance?
Which vegetables can be prepped ahead and how to store them so they don't discolour, dry out or go slimy.
- Difficulty
- beginner
- Time
- 45 min
- Read
- 2 min
Short answer
Most hardy vegetables — carrots, onions, peppers, broccoli — prep fine a few days ahead in airtight containers in the fridge. Potatoes and apples need to be kept under water or acidulated to stop them browning, and leafy things should be washed but stored dry with kitchen paper.
Prepping ahead saves the most time on the days you least want to cook, and most vegetables tolerate it far better than people expect. The exceptions are the ones that oxidise — potatoes, apples, avocado — and those need a specific trick rather than avoidance.
What you'll need
- Airtight containers
- Kitchen paper
- Lemon juice (optional)
Step by step
- Prep hardy vegetables up to 3–4 days ahead: carrots, onions, peppers, celery, broccoli, cabbage.Airtight container in the fridge. These hold up well and the time saving is real.
- Keep cut potatoes submerged in cold water in the fridge, up to 24 hours.Water excludes the oxygen that causes browning. Drain and dry thoroughly before cooking or they won't crisp.
- Toss cut apples, pears and avocado in lemon juice.The acid slows the enzymatic browning reaction considerably.
- Wash leafy greens and herbs, then dry them thoroughly before storing.Wet leaves rot. A salad spinner then kitchen paper in the container.
- Store cut onions and garlic in separate sealed containers.Their smell transfers readily to everything else in the fridge.
- Blanch and freeze anything you've prepped too much of.Blanching stops the enzymes that cause off-flavours in the freezer. Two minutes in boiling water, then straight into iced water.
- Label containers with what and when.Prepped vegetables in identical containers become unidentifiable within days.
Tips
- Prep once for several meals — do a full batch of onions or carrots and use them across the week. That's where the time saving is.
- Carrots and celery keep crisp for a week or more submerged in water in the fridge, changed every couple of days.
- Don't prep mushrooms far ahead — they discolour and go slimy quickly. A day at most, in a paper bag.
- Prepped vegetables lose some nutrients over time, but the amount lost is small next to the benefit of actually cooking rather than ordering in.
Common mistakes
- Storing washed leaves wet — They rot within a day or two. Dry thoroughly first.
- Leaving cut potatoes exposed to air — They brown within an hour. Submerge them in cold water.
- Prepping mushrooms and avocado days ahead — Both deteriorate fast. These are same-day items.
- Not labelling containers — Chopped white vegetables all look alike after two days.
Questions people ask
How long do prepped vegetables last?
Three to four days for most hardy vegetables in an airtight container in the fridge. Leafy greens and mushrooms are shorter; potatoes under water about a day.
Why do cut potatoes go brown?
Enzymatic browning when the cut surface meets oxygen. Keeping them submerged in cold water excludes the oxygen and prevents it.