Keeping Meat and Veg Apart: Avoid Cross-Contamination, the Chef's Way

When cooking a meat dish and a vegetarian dish side by side, the food you have to worry about most isn't the meat — it's the veg. Raw meat, poultry and fish carry bacteria like salmonella, campylobacter and E. coli, however the cooking process (subject to getting things to the right temperature) will kill. The trouble starts when those bacteria hitch a ride onto something that won't get cooked or cooked again, or onto the plate of someone who doesn't eat meat at all. That's cross-contamination, and in a fast-moving gastro pub kitchen it's the thing I was trained to be most careful about.

The way we handle it on a commercial level is worth borrowing at home, and you can do it without turning your kitchen into a laboratory.

How a commercial kitchen does it

The whole system in a professional kitchen is built around one idea: raw protein never touches anything it shouldn't. We do that through physical separation of work zones not just process alone, mainly because we are often many people delivering many many dishes in a kitchen at once. At busy times vigilence and basic process can, and do, fail.

The clearest example of something we do to specifically combat contamination is the colour-coded board system. It isn't the law in the UK, but it's the accepted way of demonstrating separation. It's written into the Food Standards Agency's Safer Food, Better Business guidance documents and process that environmental health officers inspect against. The standard colours are:

• Red — raw meat and poultry
• Blue — raw fish
• Green — salad, fruit and herbs
• Brown — vegetables
• Yellow — cooked meat
• White — bakery and dairy
• Purple — free-from and allergen-controlled food

Knives, tongs and even cleaning cloths can be colour-matched too, so a knife that's cut raw chicken never goes near a tomato. A chef also typically only uses their own knives. This is both for familiarty with the chosen knife (I have small hands so like a smaller and lighter feel), as well as knowing what I have done with it at each stage of a shift. However, practicality means that a chef is not necessarily going to have a never ending supply of multi coloured knives and utensils, so the standard also teach you a logical approach to avoiding contamination. Slice the vegetables first, then clean the utensils properly with detergent and water, before moving onto the next food group.

We also help to ensure contamination is avoided by working in zones in the kitchen: raw prep happens in one area, ready-to-eat in another, and often deserts in a third.
Raw meat is always stored on the bottom shelf of the fridge so it can't drip onto anything below it. Hands get washed between tasks — not because someone's watching, but because it's drilled in until it's automatic.

The principle underneath the whole system is actually really simple: one-way flow. Food moves from raw to cooked to served, and nothing travels backwards.

Bringing it home

You don't need a commercial setup to cook safely, however you do need to apply the same principle. Separation of raw meat and pretty much everything else, but applied to a smaller space and often a team of 1 or occasionally 2 of you cooking the meal. There are two simple routes you can take:

Route one: good habits and organisation

If you'd rather not buy anything, you can manage cross-contamination through order and discipline with what you already have (subject to some good material choices for things like boards, which I will write about in another article). This works well; it just takes a bit or planning, practice and patience.

Prep the vegetarian and ready-to-eat food first, while every surface is clean. Start by wiping down the surfaces with a goos anti bac spray. You never know what has been put on the work surfaces at home (I would not be surprised to walk in a find a car part or sports kit on ours!).
Salad, herbs, the veg for the meat-free version — get all of it chopped and set aside before any raw meat is out of its packaging. Once the meat is on the board, that board and knife are "dirty" until they're washed.
Many people think you need to do the salad last so it stays fresh, however we pre-prepare the componets of a salad and simply mix then onto the plate. We won't, for example, put the sliced cherry tomatoes into the mixed leaves until we are plating up, but the tomatoes are not sliced onto every plate individually, we do them ahead. When preparing at home you can mix the salad before you start cooking the meat and store it in the fridge, unless it is something like a sous vide joint that is going to be cooking for 12+ hours!

Keep raw meat to one board and one knife, and don't let them wander. When you've finished with them, wash in hot soapy water, then dry — don't just rinse and carry on. If you don'e have enough to separate (2 will do), that bowl of hot soapy water and the order you prepare in are the key things to focus on here.

Store raw meat on the bottom shelf of the fridge, sealed, so nothing can drip onto the veg or anything you'll eat cold.

Wash your hands between handling raw meat and touching anything else — including taps, drawer handles and your phone, all of which spread bacteria around the kitchen. Maybe treat yourself to a nice soap for the kitchen. Washing my hands as much as I did they became used to it, but for the first few months I wondered if they were ever going to recover!

The catch with the habits only approach is that it falls apart when you're rushed or distracted. If you cook for a mixed household several nights a week, that pressure adds up and it's when you slip.

Route two: a set of colour-coded boards

This is what I'd recommend for most households where someone eats differently, and it's the closest thing to a commercial setup you can buy. A set of colour-coded boards costs very little and removes the guesswork entirely. You don't have to memorise the full professional scheme — even a simple split works beautifully at home:

• one board (say red) for raw meat and fish,
• one board (green) for everything raw and ready-to-eat: salad, fruit, herbs, and the veg for your meat-free dishes.

Add a separate knife for each and you've built physical separation into your kitchen. There's no decision to make under pressure — the colour tells you. For a household cooking a vegetarian or vegan version alongside a meat one, this is the single change that makes the biggest difference to safety and, honestly, to peace of mind.

What it comes down to

Controlling cross-contamination has less to do with scrubbing harder than with order. It has more to do with preparation and deciding in advance that raw meat and the food your vegetarian, vegan or food intolerant diners will eat never shares a surface, a blade or a pair of hands. Commercial kitchens build that separation into colour-coded kit and different areas of the kitchen. At home you can recreate it with a little organisation or a cheap set of boards. Either way, the goal is the same — everyone at the table eats well, and no one gets ill or have their standards, choices or ethics compromised.

What's next

I have a couple more thoughts and ideas to share, next will be choice of chopping board materials. Do you really want that lovely looking wooden board getting raw chicken juice on it?