Frozen and canned fruits last longer and are usually cheaper.
However, many people avoid them in the supermarket because they believe that fresh is always healthier.
But is that really true? Not quite, say nutritionists.
In fact, produce found in the freezer and aisles in the cupboards can be just as nutritious.
Here MailOnline explains their logic.
Vitamin C, essential for maintaining healthy skin and bones, has been shown to be prone to being lost after harvest. But freezing fruit can help preserve vitamins
The benefits of frozen fruit
Fruits begin to lose nutrients as soon as they are picked.
For example, vitamin C levels, which are considered vital for maintaining healthy skin and bones, can drop by half in just a few days.
But they can take even longer to be consumed, due to the time between picking the fruit and selling it in a store and eventually eating it.
Experts believe there are three ways fresh fruit loses its nutrients.
Exposure of fruit to light and air can cause photo-oxidation, a process that causes vitamins and nutrients to be broken down, explained Professor Gunter Kuhnle, an expert in nutrition at the University of Reading, in an article in The conversation.
Natural enzymes found in fruits can also cause nutrient levels to drop over time and color and flavor to be lost.
In addition, microorganisms from the soil can find their way into fruit and, over time, break down and feed on the nutrients.
However, freezing can preserve the nutrients.
First, fruit is blanched — briefly exposed to boiling water or steam — which inactivates the enzymes, preventing nutrient loss.
The temperature of fruit is then lowered to about -20C (-4F), freezing the water in the food.
This slows down the chemical reactions that occur in food, preventing the loss of important nutrients such as vitamin C, polyphenols and some antioxidants.
While blanching and freezing itself can lead to nutrient loss, the exact amount depends on the individual food.
And in many cases, the fruit retains “more important nutrients” than it would if it had been picked just before peak ripeness and sold in a supermarket, Dr. Kuhnle said.
For example, frozen blueberries contain similar or higher nutrients than the fresh option, he said.
And tests have shown that this is also the case for peas and broccoli.
And polyphenols — a natural compound found in fruits and vegetables that act as antioxidants in the body — are better preserved by freezing, according to Dr. Kuhnle.
In most cases, he says, this means that “no one type of food is significantly better than the other.”
But despite maximizing vitamin content, the flavor and texture of fruit can be affected by the freezing processes.
‘The main difference between fresh and frozen fruit may be the texture, as the freezing process can damage the cells in delicate fruits like strawberries, reducing them to mush,’ says Dr Duane Mellor, registered dietitian at Aston University in Birmingham.
Nutritionist Kim Pearson recommends eating frozen berries to easily add nutrients to your diet.
She said, “I recommend frozen berries to many of my customers. It is a low sugar fruit and great to add to protein smoothies.
“You can also cook them with chia seeds and xylitol (a more natural sweetener) to make chia jam, which is a much healthier alternative.”
Nutritionists say you should watch out for added sugars in canned fruit, as it’s often in syrup rather than water
WHAT SHOULD A BALANCED DIET LOOK LIKE?
Meals should be based on potatoes, bread, rice, pasta or other starchy carbohydrates, ideally whole grains, according to the NHS
Eat at least 5 servings of different fruits and vegetables every day. All fresh, frozen, dried and canned fruit and vegetables count.
Basic meals on potatoes, bread, rice, pasta or other starchy carbohydrates, preferably whole grains.
30 grams of fiber per day: This is the same as eating all of the following: 5 servings of fruits and vegetables, 2 whole-wheat muesli biscuits, 2 thick slices of whole-wheat bread, and a large baked potato with skin.
Have some dairy or dairy alternatives (such as soy drinks) and choose lower-fat, lower-sugar options.
Eat some beans, legumes, fish, eggs, meat and other proteins (including 2 servings of fish per week, one of which is oily).
Choose unsaturated oils and spreads and consume in small quantities.
Drink 6-8 cups/glasses of water per day.
Adults should consume less than 6 g of salt and 20 g of saturated fat for women or 30 g for men per day.
Source: NHS Eatwell Guide
The benefits of canned fruit
Food canning involves a tougher process.
Most fruits and vegetables must be boiled in water before sealing in a can, which can significantly reduce their vitamin content.
But this harsh process doesn’t kill off all the nutrients, because vitamin A — vital for healthy skin, eyes and immune system — is preserved in higher levels compared to freezing.
And lycopene, an antioxidant that makes tomatoes red, is even higher in canned tomatoes than in fresh, according to Professor Kuhnle. It has been linked to a lower risk of cardiovascular disease and cancer.
However, vitamin C is depleted when fruits and vegetables are canned. This is because the vitamin is water soluble, which means it is easily broken down in water.
Professor Kuhnle said: ‘It should also be taken into account that some vitamins (particularly the water-soluble ones) leach into the liquid, which can affect the contents in cans (depending on whether the liquid is used or not).’
While the texture of some fruits and vegetables may change when canned, they usually still contain the same amount of fiber.
Professor Kuhnle said: ‘In most cases the process would not affect the fiber content. For example, fresh peas (boiled in water) contain about 5 g/100 g of fiber. Canned peas also have 5g/100g.’
However, you should watch out for added sugars in canned fruit, as it is often in syrup rather than water.
Dr. Mellor said: “When it comes to canned fruit it’s important to know what it’s in, if it’s in fruit juice that may contain other vitamins and minerals – but it will also have some sugar, but if it’s canned in syrup, then it just contains much more sugar.’
But he adds that ultimately the best fruit is simply “the fruit that gets eaten.”
Miss Pearson also advises people to avoid dried fruit.
She said: ‘Avoid eating dried fruit and drinking fruit juices and store-bought smoothies because of their particularly high sugar content.
‘The body can’t tell the difference between sugar from cake and sugar from fruit. While fruit is naturally healthier than most cakes, sugar is sugar.’
But she added that buying fruit that has just been canned in water is also nutritious.
