This is probably old news to many you, but I only found out/realised/ woke from a coma yesterday to notice that Innocent Smoothies (among other packaged smoothie brands) are pasteurised. Having been foodless all day due to food poisoning (I may never trust a bramley apple sausage again) I finally decided to brave something late in the day. The Innocent Smoothie had come free with my grocery order the night before, and I thought, well, given I’ve lost a lot of fluid, nutrients etc., that this would be a reasonable option, and easy on the tummy!
At first I thought the smoothie was already past its expiry date (hey, when food attacks you, you pay more attention to things like that), but LO! the expiry date on this FRUIT smoothie was MAY 9th, not APRIL 9th. Clearly, I’m naive to the ways of BIG SMOOTHIE*, as when I examined the bottle more closely it states that it is, in fact, pasteurised. More specifically, flash pasteurised, which relies on heating the juice (or as one paper called it, the SUBSTANCE, mmmmm, I love a yummy SUBSTANCE) at ~ 100 degrees celsius, for shorter periods of time than ultra heat pasteurised (UHT) ‘substances’, so somewhere in the region of 15 – 30 seconds.
From a public health and safety POV, flash pasteurisation is a good thing, killing harmful bacteria and also extending the life of the juice. Quite a few companies have been doing it since the middle of the last century, but it in the wake of the raw foods**, preservative free surge of the mid 1990s, some juice makers, like Odwalla (originally of Half Moon Bay, California, now of Coca Cola) went properly naked, if you will, and sold un-pasteurised juices to be as close to ‘raw’ and ‘fresh’ as possible. This nutritionally well intentioned choice turned fatal when a 16 year old died from the apple juice that was a key ingredient in numerous Odwalla products.
Today in the US, all store bought juices must be pasteurised. The only way to get a properly fresh juice or smoothie is to do it yourself or go to a fancy schmancy fresh juice bar. If neither is an option and you go for bottled what are you getting? The short answer is a lot of sugar and likely, fewer nutrients than you would from fresh.
Manufacturers argue that flash vs UHT is better for the consumer in terms of nutrient retention though the overal benefit seems to be in a better and more ‘natural’ tasting juice/smoothie. A 2009 study from Rutgers University showed a much greater loss of raw materials (antioxidant, anthocyanin and total phenolic content) in juices processed to become frozen concentrate compared to flash pasteurisation (Skahill, 2009) but as the substances underwent further processing to become ‘beverages’, the retention between the two methods was insignificant.
Another recent study hypothesised that it’s more likely the method of extraction and ‘finishing process’ that have a greater effect on the final product than pasteurisation in terms of taste and quality, and should be studied further as many manufacturers search in anger a for closer to ‘fresh-squeezed’ option (Baldwin et al., 2011). Still, some feel that the nutritional loss from any pasteurisation method is worth eliminating where possible and current exploration is focussed around alternate processes like microfiltration, which may further retain the integrity of the fruit and its nutritional value (de Oliveira et al., 2012).
So while flash pasteurisation isn’t a completely evil thing, if you’re a vegan or a rawist (or whatever), it’s likely the pasteurisation process won’t meet your standards of purity and ethics. If you’re going for maximum nutrition, you’re probably out of luck with a bottled smoothie, as the thing that seems best retained is the sugar from the fruits. Sure, it’s OK in a pinch, but I’m hard pressed (fnar) to accept that a 250mL bottle of an Innocent whatsit smoothie *really* gives you ‘two of your five a day’ (another concept that’s problematic, but I digress…) what with any pasteurisation process involved. Your best bet is still homemade or the fancy juice bar round the corner. Or hey, go the totally non fuss way and EAT THE FRUIT WHOLE. Crazy, I know…
A former personal trainer of mine once gave me the advice of “don’t drink your calories”, and much as I love a smoothie now and then, from a nutritional standpoint, I could’t agree more.
* OK, I don’t really believe in a BIG SMOOTHIE conspiracy, stop sending me tin foil…
** raw foodists advocate not cooking any food above 40 degrees celsius
Baldwin, E. A., Bai, J., Plotto, A., Cameron, R., Luzio, G., Narciso, J., et al. (2012). Effect of extraction method on quality of orange juice: hand-squeezed, commercial-fresh squeezed and processed. Journal of the Science of Food and Agriculture, 92(10), 2029–2042. doi:10.1002/jsfa.5587
Skahill, B. A. (2009). Effects of Thermal Processing on Antioxidant, Phenolic and Anthocyanin Levels in Blackcurrant Juice Rutgers, The State University of New Jersey, 1–67.
de Oliveira, R. C., Docê, R. C., & de Barros, S. T. D. (2012). Clarification of passion fruit juice by microfiltration: Analyses of operating parameters, study of membrane fouling and juice quality. Journal of Food Engineering, 111(2), 432–439. doi:10.1016/j.jfoodeng.2012.01.021