Monday, February 22, 2010

Is Orange Juice With Pulp Better For You?

All you have to do to understand the complex slurry of nutrients in your average piece of fruit is watch any of the countless documentaries about food being produced. You can watch The Future of Food or Food Inc., or read some random book about diet and learn about pectin, fiber, sugar, and the extra calories burned by eating raw food. So this raises an obvious question for the American breakfast eater: is OJ with pulp better for us?

It's not an easy question to answer. According to Tropicana, with pulp or without, the nutrition facts for orange juice are identical. But as we all know, the nutrition facts that companies are required to print are completely inadequate — if for no other reason than we still don't fully understand the way our body digests food. For example, it would be nigh-on impossible to get fat on raw apples, but you could easily pack on the pounds with apple juice or pan-seared apples.

Also, it just seems obvious that there has to be something in that pulp. It can't just be nothing. So what the hell is it? Well, scientifically, they're vesicles. Specialized cells that do nothing but store juice. The membrane of those cells is what comprises the pulp.

Picture stolen from Ciprex

As you can see from the diagram, those cells only make up about 2.7% of the total volume of the orange, so whatever they're made of, it doesn't comprise much. The vast majority of what is in an orange is in the juice. Unless you count the peel, which no one eats. Except for weirdos.

As with a lot of nutritional things, if the information is identical, we have to turn to scientific research for some kind of quantifiable benefit. Lucky for us, we have precisely that!

Orange pulp improves antioxidant status and suppresses lipid peroxidation in orchidectomized male rats

Nutrition, Volume 23, Issues 7-8, July-August 2007, Pages 617-621

Objective- Oxidative stress is linked to an increased incidence of cardiovascular disease in men. The objective of this research was to delineate whether daily consumption of orange pulp (OP) modifies antioxidant status and decreases cardiovascular risk factors in orchidectomized rats.

Methods- In the present study, 45 1-y-old male rats were randomized to a sham-control group (n = 9) and an orchidectomized group (n = 36). The orchidectomized group was equally divided among the following five treatments: orchidectomy (ORX), ORX + 2.5% OP, ORX + 5% OP, and ORX + 10% OP.

One hundred twenty days after the study began, all rats were sacrificed and plasma was harvested for its antioxidant status, C-reactive protein (CRP), lipid profile, and indices of peroxidation. Superoxide dismutase (SOD) and catalase activities in the liver were also monitored.

Results- Orchidectomy decreased (P < 0.05) plasma levels of antioxidant, SOD, catalase, and CRP and increased (P < 0.05) plasma levels of malondialdehyde, nitrite, and lipid profile compared with the sham-control group. In contrast to ORX, ORX + OP increased (P < 0.05) plasma antioxidant, dose-dependently increased (P < 0.05) SOD and catalase, decreased (P < 0.05) plasma malondialdehyde, nitrite, cholesterol, and triacylglycerol concentrations in the liver; and had no effect (P > 0.1) on plasma CRP or lipid profiles.

Conclusion- The beneficial effect of eating an orange is demonstrated by the increasing antioxidant status and by the decreasing peroxidation independent of plasma triacylglycerol, cholesterol, or CRP concentrations.

So it IS better for you to keep the pulp in the OJ... but for some unknown reason. Whatever the hell pulp is can be turned into fiber and other things for food alteration, but it's not fiber when we get it, nor does it affect the nutrition label.

Pulp contains a lot of flavonoids. In fact in your average orange, nearly all of the flavonoids are contained in the pulp. And flavonoids don't show up on any label, but our body does something with them, so is there any benefit to consuming them. As this study shows, the flavonoids do not have a direct effect on the body, but instead seem to stimulate the body's own waste-removal systems, which pumps more of the "bad stuff" out of our system. That somewhat jives with what we read in the previous journal entry.

So, still, it seems that we can be at least somewhat confident in the belief that OJ with pulp is better than without, but it is a very mild and indirect effect. If your diet is otherwise healthy and balanced, drinking pulp-free OJ, if that's your predilection, is no worse than drinking OJ that's practically a solid.

But is eating an orange better than the juice? Considering that diagram, and seeing that what we actually eat in an orange is primarily juice anyhow, what's the huge benefit to eating the fruit? I think that our own behavior has more to do with this than anything. An 8oz glass of OJ requires upwards of five oranges. A person can easily bang back 8oz of juice, and likely more. But eat five oranges in a sitting? Very few people do that. The process just naturally results in fewer calories.

I also think that the simple process of digesting results in fewer net calories in an ounce-for-ounce comparison. Even though there is pulp in OJ, it's been heavily machined. Much of the energy that would have been expended by our jaws and stomachs in processing the food has already been done, meaning more easy calories. Much of the raw food movement is predicated heavily on this idea, but I suspect, and the scientific evidence indicates, that this is a small effect.

Still, I think the conclusion to be reached is that the difference between OJ with and without pulp is very small and, if anything, indirect. You can achieve it by simply having a good, all-around diet. The difference between an actual orange and juice is nothing more than calories. So if you watch your calories around the OJ, eat, drink, it's whatever you feel like.

UPDATE 6/14/2010:

Previously, I had said that there is no difference in taste between OJ with or without pulp. That was apparently incorrect. I had never noticed before, but a recent taste test of juices showed pretty conclusively that OJ with pulp is lower on both sourness and bitterness. The differences are small, but noticeable. If you strongly prefer OJ without pulp, you're not sacrificing much.

BUT, if you want juice with absolutely fantastic flavor, pick up a bottle of Orchid Island, which came in first in that same taste test. You can buy it branded as Dave's own OJ at most Dave's Markets in Rhode Island. They don't keep it near the ordinary OJ, they usually store it in that gourmet juice section of the produce aisle. Is Orchid Island worth twice the price? Amazingly, yeah. It is. It tastes significantly better than any of the major brands. It's a truly delicious juice.