Pasteurization does reduce some nutrients in juice, but the losses are smaller than most people assume. Vitamin C takes the biggest hit, typically dropping anywhere from 2% to 35% depending on the method and juice type. Minerals like potassium, calcium, and magnesium survive heat processing almost entirely intact. And some beneficial compounds, like the antioxidant lycopene in tomato juice, actually become easier for your body to absorb after heating.
The real picture is more nuanced than “raw is better.” How much nutrition you lose depends on the type of pasteurization, which nutrients you’re looking at, and how long the juice sits on a shelf afterward.
What Pasteurization Actually Does to Juice
Pasteurization uses heat to kill harmful bacteria and parasites. The FDA requires juice processors to reduce dangerous pathogens like E. coli, Salmonella, and Listeria by 99.999% (a “5-log reduction”). The most common method for juice, called HTST (high temperature, short time), heats juice to about 160°F for just 3 to 6 seconds. That brief blast is enough to neutralize pathogens without cooking the juice.
Shelf-stable juices sold in cartons at room temperature go through more intense processing. A typical hot-fill process heats juice to 194°F for 2 seconds, then fills containers at 185°F and holds them at that temperature for a full minute. The higher the heat and the longer the exposure, the more nutrients are affected.
Vitamin C Is the Most Vulnerable Nutrient
Vitamin C is heat-sensitive and water-soluble, which makes it the nutrient most affected by pasteurization. But the range of loss varies dramatically. Pasteurizing blackcurrant nectar at 176°F for 27 seconds resulted in only a 2 to 6% loss of vitamin C. Strawberry juice pasteurized at a higher temperature (185°F) lost about 35% of its vitamin C compared to filtered but unheated juice. Sterilization, a more extreme process used for long-shelf-life products, can destroy 51 to 56% of vitamin C.
The method matters enormously. Standard HTST pasteurization at 160°F for a few seconds sits on the gentler end of that spectrum. If you’re buying refrigerated, not-from-concentrate orange juice, you’re getting a product that went through relatively mild heat treatment. Shelf-stable juice boxes and cartons, on the other hand, have been through more aggressive processing and will have lost more vitamin C.
Minerals Survive Heat Processing
If you’re drinking juice for potassium, magnesium, or calcium, pasteurization is not a concern. A comparative analysis of freshly squeezed and commercial orange juices in Europe found that mineral profiles between fresh and processed juices were broadly similar. Not-from-concentrate commercial juices actually showed the highest levels of potassium, magnesium, and iron among the commercial categories tested. Heat doesn’t break down minerals the way it breaks down vitamins, because minerals are elements, not complex molecules that can be degraded by temperature.
Some Nutrients Become More Available After Heating
Here’s where the story gets interesting. Lycopene, a powerful antioxidant found in tomato juice, exists naturally in a molecular form (called all-trans) that your body has a hard time absorbing. It sits in large crystalline structures inside the plant cells, making it difficult to extract during digestion. Heat processing converts some of that lycopene into a different shape (cis-isomers) that dissolves more easily and is significantly more bioavailable. Research in human subjects confirmed that lycopene from heat-processed tomato sauce was more bioavailable than lycopene from minimally processed tomato products.
This principle applies to other carotenoids as well. Heating breaks down plant cell walls, releasing compounds that would otherwise pass through your digestive system only partially absorbed. So for tomato, carrot, and similar juices rich in carotenoids, pasteurized versions may actually deliver more usable nutrition than raw ones.
What Pasteurization Does to Enzymes
One claim you’ll encounter from raw juice advocates is that pasteurization destroys beneficial enzymes. This is technically true but nutritionally misleading. Heat does deactivate enzymes in juice, typically at temperatures between 150°F and 195°F. But the enzymes naturally present in fruit juice serve the plant, not your body. They include enzymes that cause browning, break down pectin, and oxidize fats. These are quality-control concerns for juice manufacturers, not nutritional assets for you.
Your digestive system breaks down virtually all food enzymes into amino acids before they could perform any function in your body. Losing these enzymes to pasteurization doesn’t change the nutritional value of the juice in any meaningful way.
Raw Juice Loses Nutrients Too
A detail often missing from this debate: fresh, unpasteurized juice also loses nutrients over time, just from sitting in your refrigerator. Research on cold-pressed and centrifugal juices found that bioactive compounds and antioxidant capacity held steady for about 48 hours at refrigerator temperature, with cold-pressed juices remaining stable for up to 5 days. But by day 6, most measured nutrients began declining, reaching their lowest values by day 7.
This means a glass of raw juice on the day you make it is nutritionally superior to pasteurized juice. But raw juice purchased from a store and consumed on day 4 or 5 may have already lost a portion of its vitamin C and antioxidants through natural oxidation. Pasteurized juice, by contrast, has a more predictable and stable nutrient profile throughout its longer shelf life because the same enzymes that cause degradation have been deactivated.
Cold-Pressed “HPP” Juice: A Middle Ground
Many premium juice brands now use high pressure processing (HPP) instead of heat. This technique subjects sealed juice bottles to extreme pressure, equivalent to being 60 kilometers underwater, for a few minutes. It kills most pathogens without raising the temperature significantly.
You might expect HPP juice to retain far more nutrients than heat-pasteurized juice, but the difference is surprisingly small. A study comparing HPP and heat-treated Concord grape puree found that both had similar levels of phenolic compounds (a category of antioxidants) and similar antioxidant activity, both immediately after processing and after four months of refrigerated storage. The main advantage of HPP was better texture and consistency rather than a dramatic nutritional edge.
The Practical Bottom Line
The nutrient most affected by pasteurization is vitamin C, and losses range from negligible to roughly a third depending on processing intensity. Minerals are unaffected. Some antioxidants become more bioavailable. Enzymes are lost, but they weren’t nutritionally useful to begin with. If you’re choosing between pasteurized juice and no juice at all, pasteurization is not a reason to skip it. A glass of pasteurized orange juice still delivers most of its original vitamin C along with all of its potassium, folate, and other minerals.
If maximizing every last microgram of vitamin C matters to you, drink freshly made juice within 48 hours. But for most people, the nutritional difference between pasteurized and raw juice is far smaller than the difference between drinking juice and not eating fruits or vegetables at all.