Cranberry juice

Cranberry juice is a bright red, acidic liquid made from the fruit of the cranberry plant. It is widely used to create many different products like dried fruit, sauces, and dietary supplements. While pure juice is very tart, many people enjoy cranberry juice cocktails or blends. These blends typically contain about 28% cranberry juice. The rest of the liquid usually consists of water and other fruit juice concentrates, such as apple, pear, or grape. Manufacturers often add sugar to these blends to make them more palatable for consumers.

Most commercial cranberry juice comes from the American cranberry, known scientifically as *Vaccinium macrocarpon*. Large-scale farming occurs in several Canadian provinces, including British Columbia, Québec, New Brunswick, Nova Scotia, and Prince Edward Island. In the eastern provinces, farmers must use irrigation and flooding to protect crops from frost. To produce juice, farmers often use a method called wet harvesting. A machine called a water reel harvester uses paddles to separate the ripe berries from their vines. A large suction pipe then collects the fruit to be sent to a processing plant.

At the processing plant, the berries undergo a specific sequence of mechanical steps. The fruit is crushed and then undergoes mash maceration and heating. After the mash is heated, the juice is pressed out and pasteurized. This process creates a cranberry juice concentrate that is separated from the pulp. To make a finished juice product, this concentrate is reconstituted with specific amounts of water. This method ensures that the final product meets the requirements of the purchase orders or contracts.

To keep the juice safe, manufacturers must eliminate pathogenic or spoilage-causing microorganisms. Traditionally, this is done through thermal processing, which uses high temperatures for short periods. These techniques are known as high-temperature-short-time (HTST) or ultra-high temperature (UHT) processing. This heat treatment is designed to achieve a 5-log pathogen reduction. Because cranberry juice is highly acidic, with a pH between 2.3 and 2.9, the bacterium *Clostridium botulinum* cannot grow in it. However, newer methods like high pressure processing (HPP) have emerged. HPP applies 80,000 psi of pressure for one to nine minutes to eliminate bacteria, molds, and viruses without using heat.

Another modern technique is pulsed electric field (PEF) technology. This method uses a high-intensity electric field to create a flux of electric current through the food. PEF is useful because it does not alter the aroma, color, or flavor of the cranberries like thermal processing can. Once processed, the juice is packaged in aseptic, hermetically sealed containers like cans, cartons, or plastic bottles. These containers must be filled to at least 90 percent capacity. For example, brands like Ocean Spray and Fruit d'Or have frozen shelf lives of 24 and 36 months, respectively.

There is much discussion regarding how cranberry juice affects health, specifically urinary tract infections (UTIs). For many years, people believed the juice could prevent these infections. However, scientific reviews have shown inconsistent results. A 2012 review suggested the juice was less effective than previously thought. By 2017, one systematic review indicated it might help people with recurrent infections. A 2023 review found evidence that it may reduce UTI risk in children and women with recurrent infections. However, there was little evidence of an effect in pregnant women or the elderly.

Because the scientific evidence is not always certain, the FDA has specific rules for labeling. In 2020, the FDA allowed a "qualified health claim" for certain products. This claim can state that drinking 8 ounces of juice daily may help reduce the risk of recurrent UTIs in healthy women. However, the label must include a disclaimer stating that evidence is limited or inconsistent. This is different from an "authorized health claim," which requires much higher scientific agreement.

From a nutritional standpoint, cranberry juice is composed of 86% water and 11% carbohydrates. It contains less than 1% fat or protein. A standard 8-ounce serving provides 107 calories and is often fortified with vitamin C to maintain freshness. One half-cup serving provides 20% of the Daily Value for vitamin C. It is important to note that the juice is very acidic, with a pH of approximately 2.6. This high acidity level can potentially erode tooth enamel over time. Additionally, products with high sugar content may affect blood glucose control in people with diabetes.