Every year a new superfood emerges – often exotic fruit or veg that have spent significant airmiles travelling to our supermarkets. Do you sometimes wonder if such hyped up superfoods really are still nutritionally superfoods by the time they have travelled, have been distributed, lived on a supermarket shelf, and languished in our fridges before we eat them?
Aside from all issues associated with a sudden increase of intense production of one specific crop, as with the avocado for example, I really do wonder if locally available foods are not nutritionally more of a superfood than those hyped up as such. It’s great to see that we slowly do return to such crops, like kale, Brussels sprouts etc, but ultimately this will be driven by consumer demand than considerations for sustainability, so let’s get the word out!
Just as an example for nutrient loss, Vitamin C degrades rapidly from the time of harvest. If stored at 4%, Vitamin C loss after seven days is for example 15% for green peas but 77% for green beans. The trick is to minimise what is called respiration by storing fruit and vegetables in a cool, moist place, except those that continue to ripen after being picked, such as bananas, avocados, or tomatoes. These are better stored in a cool place but not in the fridge.
In a study published by the University of California our popular superfood broccoli for example, which typically is imported from Spain over the winter months, loses 56% of in Vitamin C content if stored at 20 degrees. There were no losses noted as long as broccoli was stored at 0 degree. In my local supermarket broccoli isn’t cooled. It may not be 20 degrees but certainly not 0 either. So considering the travel time I really do wonder how much nutrients are left by the time I boil it. This of course causing even further vitamin loss (steaming better obviously), between 15% and 55%. How many vitamins are left by the time it gets into my mouth? (There are obviously other nutrients other than water soluble ones that may be a little less perishable, but it definitely gives me something to think about further.)
Airmiles for superfoods
So where do our current superfoods come from – those that we eat fresh and for their soluble nutrients rather than minerals, so not quinoa or acai berries. Avocados mainly come from Mexico or Peru for EU countries, blueberries may come from Poland or Germany when in season but from Mexico, Peru, or Chile during winter, strawberries are great in summer and grown locally for quite a long season, but during the winter they may be imported from the US, Egypt, or Mexico. Blackberries may come from Guatemala during winter. The apples we buy in supermarkets may have been stored in a climate controlled environment for up to 12 months…
Aside from pollution, potentially questionable growing practices, why would we eat foods at such unnatural times and against any natural cycle? I know we all want to have healthy blueberry smoothies especially in January but can we not replace blueberries with something a little more local, maybe fruit that is only imported from Southern Europe? It doesn’t even taste right I think. I prefer to mark the change of seasons by changing the food I eat too, including fruit and veg.
Ripe local fruit or unripe exotic superfood?
Worth considering also that especially fruit that is picked for export halfway around the world will be picked very unripe. This will impact on taste obviously but also on the nutritional value – anybody ever tried a locally grown mango? The sweetest pineapple I’ve ever eaten was most definitely in Panama which is apparently the secret pineapple growing mecca. And clearly avocados can taste very different to those often grainy tasting ones we can buy in our stores.
When it comes to storage it’s probably rather obviously that nutrients are retained better in uncut fruit. Unless bought for a quick snack I don’t understand these overpriced, pre-cut fruit cups that seem popular in supermarkets
Spinach, a locally grown superfood, especially in regards to its Vitamin contents, clearly is quite a perishable food. I’d like to be a lot more conscious for how long I keep fresh spinach in the fridge as I really wonder how many vitamins are still left by the time I put them through a juicer. Here is a an idea that could really help consumers: Instead of indicating a display until date, would it not be great to see a date by which a high percentage of nutrients is lost?
All of these just further arguments for buying and eating more local food and ideally grow one’s own food. Good that this is something I want to work on anyway.