I love it when my friends give me health topics to research. The reason I started this blog is because I want to know these things. I want to combine my passion for health with an expansive knowledge of what it really means to be healthy, while staying up to date with the ever-changing trends and studies that keep emerging. The internet can be a confusing place full of conflicting information. Everyone’s an armchair doctor or a keyboard activist these days, and it’s exhausting.
Have you ever sat at a dinner party and a subject comes up, and one of your friends starts talking like they’re the absolute authority on this issue, and you’re looking at them going, yeah I don’t really know whether to believe you? It’s not that you don’t trust your friend. You’re just not sure how well they researched their sources before they started pontificating. Everybody knows everything about everything in this digital age. Except that most people really don’t know anything – they’re simply regurgitating what other people ‘know’.
Ok great, so now that we’ve established we can’t trust anything anyone says, let’s dive into fresh vs frozen food! This topic was raised by my friend Dino while we were chatting the other day and immediately I knew it needed to be a blog.
Here are some of the questions we’re going to delve into.
- Fresh vs frozen food – which has greater nutritional value?
- What are the pros and cons of buying frozen?
- From frozen to ready to eat – does it matter how you heat up your food?
There’s a general belief that buying frozen food is the cheap way out and therefore the produce is not as good or healthy. I’ve never believed this, having read somewhere many moons ago that freezing actually preserves the nutrient content. A quick search confirms that for the most part, this is true. Foods that are selected to be frozen are harvested at their peak ripeness and processed immediately, meaning there’s no deterioration – the nutrients are literally frozen in time until you consume them.
The main variable here is that nutrients don’t all behave in the same way. The first step in the freezing process involves blanching veggies in hot water or steam to kill bacteria. Some water soluble nutrients like vitamins B & C will break down or leach out at this point, so it makes a case for choosing fresh over frozen for these nutrients. The veg is flash-frozen after blanching, locking in all remaining nutrients. Most fruits are not blanched before freezing, so the nutrient content remains relatively unaffected.
Fresh fruit and veg, on the other hand, are often picked before they’re fully ripe to give them time to be transported to their destinations without spoiling. This means they don’t always have time to develop their full range of nutrients, as the ripening process plays an important role here. Long journeys with exposure to heat and light can also break down some of their nutritional content.
The multiple studies I read advocate a mix of both fresh and frozen food in your diet. Fresh fruit and veg will be especially healthy if it hits your table very soon after harvesting, making an excellent case for visiting your local farmer’s market, only buying local products in your supermarket or growing your own. The rule of thumb is if a food is in season, buy it fresh and ripe and eat it soon after purchasing. If it’s off-season, buy frozen and eat within 4-6 months.
So what are the cons? Besides the breakdown of some nutrients and antioxidants in the blanching process, many frozen foods are loaded with sugar or sodium, fats or preservatives to influence their colour or texture. To be fair, this is usually only when the food has sauces or spices added to it – so plain fruit and veg should be free of these. It goes without saying that you need to check the ingredients on the packaging before you buy. Find a brand that doesn’t add these extras and stick to it.
I’ve chosen to talk about fruit and veg in this post, but ready meals are of course the big concern here – the nutrient content is likely to be highly influenced by the additives required to maintain these foods. If you see a list of unidentifiable, unpronounceable items in the ingredients, rather choose fresh.
The other big influencing factor in the nutrient content of frozen food is how you heat it. I’ve always avoided microwaves where possible (which, to be honest, is often not very possible at all). I don’t believe they have cancer-causing rays or whatever other old wives’ tale is doing the rounds, but I’ve always thought that, much like the freezing process influences nutrients, heating something up to high temperatures very quickly must do the same. This is a vague conviction I have though, certainly not based on any fact I can remember reading, so I was interested to find out whether I was right.
I knew that you’re not supposed to boil frozen veg. A long cooking time combined with lots of water is the fastest way to destroy nutrients, making boiling the worst way to cook frozen foods. I mentioned the breakdown of unstable water soluble vitamins earlier – it’s obvious that an extended time in boiling water is going to leach these out of the food as well. Some nutrients, like vitamin C, are largely destroyed by the heating process, regardless of how you do it. Steaming is an accepted way of cooking veg quickly with minimal nutrient loss as it doesn’t come into direct contact with the water. Roasting veg is also good, as the dry cooking method helps to retain nutrients.
But what about microwaves? What I found is interesting. As we’ve seen, the number one enemy of nutrient loss in cooking is water. Microwaves actually use less heat than some other cooking methods and they involve shorter cooking times. The general consensus among studies done is that as long as you use a very minimal amount of water and don’t overcook your vegetables, microwaving actually preserves a high degree of nutrients. It’s especially good for retaining antioxidants, although steaming has been shown to better retain minerals and vitamins. For info, I read up on some of the latest published studies to get this data. If you go much earlier than 2015, microwave studies are full of doom and gloom and we should all be dead.
As with literally anything I’ve ever researched for this blog, the key is always: everything in moderation and find your balance. Don’t eat all frozen veg or heat everything up in the microwave – buy a variety of products and cook them in different ways, as much for different textures and flavours and your own sanity as for your health. Right, I’m off to heat up my vegan bean mastermix…in the microwave. 😉