Pasteurized orange juice has been briefly heated to a high temperature to kill harmful bacteria, then cooled and packaged for sale. Nearly all orange juice sold in grocery stores is pasteurized. The process makes the juice safe to drink and extends its shelf life from a few days to weeks or even months, depending on packaging.
How Pasteurization Works
Pasteurization is a quick blast of heat, not a long cooking process. For orange juice, the standard method heats the juice to at least 160°F (71°C) and holds it there for a minimum of 3 seconds. That’s enough to destroy 99.999% of dangerous bacteria, a benchmark the FDA calls a “5-log reduction.” The juice is then rapidly cooled so it doesn’t taste cooked.
For shelf-stable juice (the kind sold in cartons at room temperature), processors use a higher temperature of around 194°F (90°C) for about 2 seconds, then fill the container while the juice is still hot at 185°F. That extra heat, combined with airtight packaging, allows the juice to sit on a store shelf for months without refrigeration.
Refrigerated pasteurized orange juice uses the lower temperatures and needs to stay cold. Once opened, it typically lasts about 7 to 10 days in the fridge. Unpasteurized juice, by comparison, stays fresh for only about 3 days.
What Pasteurization Kills
Raw orange juice can harbor several pathogens that cause serious foodborne illness. The main targets of pasteurization are E. coli O157:H7, Salmonella, Listeria, and Cryptosporidium. These organisms can end up in juice through contaminated fruit, soil, or processing equipment. Orange juice’s natural acidity slows bacterial growth but doesn’t eliminate it, which is why heat treatment is necessary for commercial products.
Healthy adults who drink contaminated juice might experience a bad bout of food poisoning. But for young children, older adults, pregnant women, and anyone with a weakened immune system, these infections can become dangerous or even life-threatening.
How to Tell If Juice Is Pasteurized
Most juice sold in standard grocery store aisles is pasteurized, whether or not the label says so explicitly. The more important label to watch for is the one on unpasteurized products. The FDA requires any juice that hasn’t been heat-treated to carry a specific warning in a bordered box on the label:
WARNING: This product has not been pasteurized and, therefore, may contain harmful bacteria that can cause serious illness in children, the elderly, and persons with weakened immune systems.
You’ll typically find unpasteurized juice at farmers’ markets, juice bars, and in the refrigerated section of health food stores. If a bottle of juice doesn’t carry that warning and isn’t sold by a very small producer exempt from federal labeling rules, it has been pasteurized.
Does Pasteurization Reduce Nutrients?
This is the concern most people have, and the answer is more reassuring than you might expect. A large-scale study that measured vitamin C and antioxidant levels across different commercial processing methods found that mild and standard pasteurization actually slightly increased total vitamin C content in orange juice. That sounds counterintuitive, but the heat breaks down cell walls in the pulp and solid particles, releasing vitamin C that was previously trapped and unavailable.
The antioxidant capacity of the juice stayed largely intact as well, with the natural vitamin C in orange juice accounting for 77 to 96% of its total antioxidant power regardless of processing method. Concentration and freezing, the steps used to make frozen concentrate, also showed no significant vitamin C losses. So choosing pasteurized orange juice over fresh-squeezed doesn’t mean you’re giving up meaningful nutrition.
High Pressure Processing as an Alternative
Some premium juice brands use a newer technique called high pressure processing, or HPP, instead of heat. Rather than raising the temperature, this method subjects sealed bottles of juice to extreme pressure, which ruptures bacterial cell membranes and kills them while keeping the juice cold. The result is a product with a taste and texture closer to fresh-squeezed juice.
Because HPP doesn’t involve heat, it preserves small molecules like vitamins and flavor compounds more effectively. It can also release bound antioxidants from fruit pulp, sometimes resulting in higher antioxidant levels than the original juice. The tradeoff is that HPP is less effective against bacterial spores than heat pasteurization, so HPP juice still requires refrigeration and has a shorter shelf life than heat-treated shelf-stable juice. You’ll usually find HPP juice in the refrigerated section at a higher price point, often labeled “cold-pressed” or “cold-pressured.”
Pasteurized vs. Fresh-Squeezed at Home
If you squeeze oranges in your own kitchen, that juice is unpasteurized. It’s generally safe because you’re controlling the cleanliness of the fruit and equipment, and you’re drinking it right away. The risk with commercial unpasteurized juice is scale: when thousands of oranges pass through industrial equipment, the chance of contamination rises significantly.
Home-squeezed juice should be refrigerated immediately and consumed within 2 to 3 days. If you notice any off smell, fizzing, or change in color, discard it. Pasteurized juice from the store gives you a much wider window, and nutritionally, you’re not losing anything meaningful in the trade.