Saturday, May 9, 2009

How Fresh Is Your OJ?

I don't buy orange juice that often. The heavy natural fructose content makes me sleepy - not a good a.m. choice! But when I pick it up for houseguests, I buy the premium, not-from-concentrate, with-pulp variety, thinking I'm getting a fresher, fruitier juice. I don't know much about orange juice production, but I've noticed that some OJ has a rather "tinny" taste. I always thought the reason was that cheaper orange juices were made by "squeezing" the rind along with the fruit meat.

Nice theory but no cigar!

Imagine my surprise to discover, while reading a story in Cook's Illustrated online (link below), that even my "premium" OJ is unlikely to be anything remotely like fresh! Fresh, even in a world where food has to be processed, packaged, and transported to market, to me still implies something like days from the orchard to my local grocer. But no. Pasteurization allows processors to store the juice for months on end. And while pasteurization uses heat to kill nasty microbes that might make us sick and to add months and months to juice's shelf life, that same heat also seriously destroys that delicious fresh-squeezed flavor and significantly reduces the vitamin C content. This is true even when the juice was treated with "flash" or "light" pasteurization that supposedly retains more flavor.

So guess what! When processors are ready to send the stored juice out to market, they simply repair the flavor deficiency with chemist-made "flavor packets" containing essences of orange oil and other orange by-products. These by-products have been scientifically "separated" into their constituent parts and stored, later to be reconstituted and added to orange juice as it is readied for market. This way they can ensure consistent flavor from quart to quart through the miracles of science. Wow. Surprise.

So of course I go off on a Google-trail, looking for more information. It turns out that a writer named Alissa Hamilton actually did an entire book about the realities of orange juice. It turns out, most OJ is not only not fresh, it's not all that healthy. According to Ms. Hamilton, a single orange is better for you than an 8 ounce glass of OJ. I googled the number of oranges in an 8 ounce glass, and it's about 3 to 4 oranges, depending on the size of the fruit. How is it, I wonder, that processing for market manages to take a wonderful natural food item and make it "less than"?

Hamilton's book, cleverly titled "Squeezed, What You Don't Know About Orange Juice," and published by Yale University Press, is out this month, and apparently available on

In fairness to the processors, the reason they do this is safety. E. coli and salmonella and goodness knows what other microbes lie in wait for the unsuspecting kid sucking on a juice box. What, if anything, can be done? More googling...(too bad someone doesn't pay me to google), and discovered that science is playing around with alternatives to thermal (heat-based) pasteurization. A non-thermal UV light process is being tested, although its efficacy depends on about a zillion factors like the liquid density, suspsended solids (brix) levels, viscosity, etc. UV breaks down vitamin C too. Maybe more promising is something called "high hydrostatic pressure" pasteurization that has some potential, because it can use lower heat (about 104F instead of 176F), with less damage to flavor, aesthetics and vitamin content.

So, while they're perfecting that technology, I can't think of a single thing to be done about this problem... except to drink more water and get more of your fruit intake from fruit instead of juice.

So, why am I writing about orange juice, and what goes into our bodies? Well, because we're part of the Earth's flora and fauna. In the same way that we have to protect the ecosystem's food sources for fishies, birdies, and forest critters, we need to protect our own food sources. Fresh food is far better for our bodies than food we've processed the fresh right out of. Back in pre-industrial times, we would have eaten whatever was seasonally available regionally. We can't really return to a fully localized agricultural economy because we've populated regions where, at least in some seasons, a return to that practice would mean a very limited diet. But if we begin to practice purchasing flexibility, opting more for fresh, local, seasonal produce, we'd find that overall both our bodies and our planet become healthier.

Of course, if you're lucky (like me) to be living in a house with five grapefruit trees, an orange tree, a kumquat tree, a lime tree, and an apple tree, you can just squeeze your own. Problem solved.

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Read the Cook's Illustrated article here: Orange Juice - Cooks Illustrated

Read an interview with Alissa Hamilton from here: Q&A with Alissa Hamilton - The Boston Globe

Check out this cool FDA site: , click search (kinda tiny link top center of the page) and plug in any food item or processing technology you're interested in, and you'll get a lot of information.

I also learned a lot from these studies: Koutchma, T.,"UV Light for Processing Food" Ozone: Science & Engineering; Jan/Feb2008, Vol. 30 Issue 1, p93-98, 6p, and
Polyderaa, A.C., Stoforosb, N.G. & Taoukis, P.S., "Quality degradation kinetics of pasteurised and high pressure processed fresh Navel orange juice: Nutritional parameters and shelf life," Innovative Food Science & Emerging Technologies, Vol. 6, Issue 1, Mar2005, Pages 1-9. I found these through the University library system. If you want to read and can't find a copy online, just shoot me an email and I'll get it to you.


  1. Wow, Sandy, you are a gem. Thank you for all your hard work. OPENED my eyes.

  2. I wonder about the "flash pasturized" juices. Are they better at all or should we just resort to squeezing our own juice if someone in the family wants it?

  3. This is stuff I thought about but thanks to you now I know it for certain!

  4. Thanks all of you for your comments. Christine, the Vitamin C degradation is still significant for juice that has been flash pasturized, although the story is somewhat better for flash than thermal pasteurization. All the studies I looked at (cited in the blog) suggest that there is still a significant Vitamin C loss from flash pasteurizing, although not as bad as thermal pasteurization. These studies looked at an assortment of processing techniques, so they won't all show the same loss figures. To give you ONE example only, in one case, the flash pasteurization method used retained about 84% of the Vitamin C, while thermal retained about 72%. However, that was the Vitamin C availability on the actual day of processing. The degradation continues from that point, throughout the product's shelf life, and as my blog points out, it may be a very long shelf life before it reaches your table. So yes, flash pasteurizing will have a somewhat longer shelf life than thermal pasteurization, but starting from a reduced availability compared to fresh (you) squeezed juice or fruit. However, the equation gets more complicated, as shelf life is partially determined by the temperature at which the OJ is stored after pasteurization. That includes storage temperatures at the production facility, but also transportation temperatures, warehousing and retail grocer refrigeration temperatures, and home storage (e.g. cold chain handling). Retailers often tend to keep their units at the highest allowable temperature, due to the increase in expense to further cool a unit. I had trouble pulling out the typical retail refrigeration for OJ, perhaps because, as I'm sure you've noticed, OJ is stored in situations from unrefrigerated juice boxes to frozen. By the way, the FDA's "don't sell" level of degradation is 50% available Vitamin C loss. Of course, you can enjoy 0% loss by eating an orange, but if you like OJ, 50% seems to be the standard. I wondered whether buying frozen juice (obviously stored at colder temps) is the answer, but what if frozen juice is stored in bulk as unfrozen product before it is eventually packaged into the little round containers we see frozen for market? I think the best bet is to squeeze the juice yourself. I read it will have twice the shelf life of processed juice in your home. I still say, drink water to avoid the fructose over-kill, eat fruit, and on special "mimosa" occasions, buy the oranges, squeeze the juice yourself (great task for a kid if you have access to one), then use the pulp when you bake bread, brownies or cookies. If you want to read more, check the citations I have in the blog (which is where I got my info) or google "orange juice" and whatever piece of this you're interested in: "cold chain" or "vitamin c" or "processing," etc. There's a LOT of stuff out there.