Posted by kathryn in Q & A Thursday

Next we’re moving into the area of food safety, with a question from Alison:

I cook lasagne fairly regularly, and generally I cook a batch of bolognaise, assemble the lasagne and then put it in the fridge. At dinner time I cook it in the oven and serve it. So the meat has now been cooked, cooled, then reheated.

The next day, when I go and look at the leftover lasagne in my fridge, I’m reminded of my mother’s rule – you can only reheat once. I usually heat up the leftovers and eat them anyway, but I often wonder if I’m putting myself and others in danger of food poisoning. Should I be cooking the lasagne as soon as it is assembled and then only heating up what we want for dinner?

Firstly I have to note I’m not a food safety expert. The information below has been gathered from a couple of different resouces and you might like to check with them directly about food safety issues. I’ve listed my sources at the bottom of this post.

However, from my research, I think reheating lasagne is fine Alison, as long as you follow these guidelines:

Cooking the bolognaise:

• Firstly, when cooking the bolognaise, you need to make sure your mince is thoroughly cooked – no pinkness should be visible.

Cooking the lasagne:

• The bacteria that cause food poisoning thrive between the temperatures of 4°C and 60°C, so it’s important to limit the amount of time your food spends at that temperature.
• Once you’ve taken the lasagne out the oven, leave it to cool for 20 – 30 minutes (no longer than one hour) and then refrigerate.
• It’s important to cool the food down as rapidly as possible, so I’d also recommend cutting up your lasagne and refrigerating in individual portions.
• Your fridge needs to be cooled to below 4°C.
• Keep your lasagne in the fridge, until you are ready to cook or serve.

Reheating the lasagne:

• Only reheat what you need for that meal.
• You must reheat the food until it’s steaming hot and keep it at that temperature for at least two minutes.
• If you’re reheating in the oven, the temperature should be above 75°C.
• Do not put your lasagne in the oven until it’s at temperature, again you’re trying to limit the amount of time the food spends between 4°C and 60°C.
• Keep your lasagne in the oven until you are ready to serve.
• I would only reheat the lasagne portions once.

How long can you keep lasagne?

• Lasagne should not be kept in the fridge for longer than three days.
• If you have a fridge/freezer you can store lasagne for up to six weeks.
• With a chest freezer, operating at minus 18°C, the time is longer, about three months.

Resources

• NSW Food Authority
• Food Standards Australia New Zealand
• Food Safety Information Council
• Food Science Australia

05 July, 2007