Citrus juice: Nutrient content and health benefits

Citrus is botanically a large family whose dominant members are the sweet orange (Citrus sinensis), mandarin or tangerine orange (Citrus reticulate), grapefruit (Citrus paradise), lemon (Citrus limon) and lime (Citrus aurantifolia).

Citrus fruits and juices are excellent sources of vitamin C containing more than the minimum daily requirements of 60 mg of vitamin C in 240 ml of juice. Citrus fruit are also a good source of folic acid, vitamin B1, thiamine, the minerals calcium, calcium, phosphorus, and potassium.

Citrus fruits contain many important phytochemicals, such as flavonoids, amino acids, triterpenes, phenolic acids, and carotenoids.

Common colds benefit greatly from a diet rich in citrus juices. Unfortunately, while convenient, pasteurized, frozen, and concentrated citrus juices do not produce the same health benefits as fresh squeezed citrus juices.

Everyone knows that citrus fruit is high in vitamin C, and while this cannot prevent from getting a cold, it can reduce the severity and duration of symptoms. An orange has about 51 mg of vitamin C, while a grapefruit has 38 mg and a lemon offers approximately 30 mg

Citrus juices taken in excess can leech calcium from the system, softening bones and teeth. If drink more than three to four 6-ounce glasses per week, make sure to get extra exercise to burn excess acid.

The flavonoids are concentrated in the white pulp surrounding the fruit. Bioflavonoids help the body to retain and use vitamin C. Together these two nutrients improve the permeability and strength of capillary walls.

According to a 2012 study published (in AHA Journals), the flavonoids in citrus fruits may help lower the risk of ischemic stroke in women. A study of data from nearly 70,000 women over 14 years showed that those who ate the most citrus fruits had a 19% lower risk of ischemic stroke than women who consumed the least.

Vitamin C is an important antioxidant and critical for production of collagen. That is why citrus juice helps heal bruises more quickly than if they were not treated with citrus juice. Lemons and lemon juice are an excellent source of the antioxidant vitamin C. Antioxidants may help prevent free radicals from causing cell damage that can lead to cancer.

Folate is a key nutrient possible for prevention of neural tube defects. Potassium functions to maintain intracellular fluid balance and as such a high intake is associated with lower of blood pressure and a reduced risk of stroke.
Citrus juice: Nutrient content and health benefits

Production of citrus juice

Among citrus juice, orange is by far the most important. Lemon, lime, grape and tangerines are also processed as juice. Natural citrus juices and concentrates are widely marketed for national and international consumption.

One of the characteristics of citrus juice is that it is to be consumed mainly as a cloudy drink. Every piece of fruit holds a different amount of juice. Factors such as variety, growing environment, and size impact how much juice a citrus fruit yield.

The fruit must be inspected and graded before it can be used. Graders remove bad fruit as it passes over the rollers and the remaining quality pieces are automatically segregated by size prior to extraction. Proper size is critical for the extraction process.

There are several methods to extract juice depending on the type of the fruit. There are two automated extraction methods commonly used by the citrus juice industry. As the extraction operation determines juice yield and quality, the correct setting of extractor operating conditions is very important.

The first places the fruit between two metal cups with sharpened metal tubes at their base. The upper cup descends and the fingers on each cup mesh to express the juice as the tubes cut holes in the top and bottom of the fruit. The fruit solids are compressed into the bottom tube between the two plugs of peel while the juice is forced put through perforations on the tube wall.

The second type of extraction has the oranges cut in half before the juice is removed. The fruits are sliced as they pass by a stationary knife and the halves are then picked up by rubber suction cups and moved against plastic serrated reamers. The rotating reamers express the juice as the orange halves travel around the conveyor line.

The extracted juice product does not contain the orange peel, but it may contain pulp and seeds, which are removed by finishers. Although juice is naturally cloudy, some consumers prefer a clear product. It may be necessary to use pectic enzymes to break down the pectin and to help clear the juice.

Although the biggest percentage of that juice is made of diluted first extraction juice that does not require enzyme treatment most of the time, there is an appreciable production of by-product that are made from pulp and the peels, and these are marketed either as second quality juice or as natural cloudifiers.

Pasteurization: The juice is heating to a temperature for sufficient time and to assure practical sterility as well as cloud stability by inactivating natural juice enzymes. Temperature of 77°C for 30 seconds is used.

The extracted juice is filtered through a stainless-steel screen before it is ready for the next stage. At this point, the juice can be chilled or concentrated if it is intended for a reconstituted beverage.

Packaging: Different types of packaging including cans, bottles, cartons, drums and barrels made up of glass, metals, plastic, or laminates are used for the packaging of Lemon juice.
Production of citrus juice

Vitamin C in orange juice

Vitamin C, also known as ascorbic acid, is water soluble, meaning it will dissolve in water and is not stored in the body. The recommended amount of vitamin C is 60 to 90 mg per day.

Orange juice is the most nutrient dense fruit juice commonly consumed in the United States. An 8 oz serving provides 110 cal and contains 72 mg of vitamin C.

Variability in the vitamin C (ascorbic acid) content of citrus fruit and their products is influenced by variety, cultural practice, maturity, climate, fruit quality, fresh fruit handling, processing factors, packaging, and storage conditions.

Vitamin C is known for its potent antioxidant properties and is lost during handling, processing and storage. Therefore, vitamin C content is widely considered as an appropriate marker for monitoring quality changes during processing and storage.

Citrus fruit juices provide an important source of vitamin C for human nutrition, even though only about one-fourth of the vitamin C content of citrus fruit is found in the juice. Vitamin C is usually considered the major antioxidant in citrus.

Vitamin C is important for the human body because it is needed in the production of collagen to make connective tissue. Vitamin C also helps the body to absorb iron, helps wounds to heal, helps red blood cell formation and helps to fight infections. Some studies say that vitamin C prevents cancer.

Vitamin C helps to enhance availability and absorption of iron from non-heme sources. Vitamin C also has antioxidant properties since it can easily lose the electron to neutralize and inhibit free radicals from being oxidized in preventing cell damage.
Vitamin C in orange juice

Vitamin C in citrus juice

Vitamin C is defined as hexuronic acid, cevitamin acid or xiloascorbic acid. The term vitamin C is commonly used to describe all these compounds even though the representative of which is ascorbic acid.

Citrus fruits provide about 51% of vitamin C and also large quantities of some carotenoids: 68% for β-cryptoxanthin and 43% for zeaxanthin.

Many factors influence the vitamin C content of citrus fruits such as lemon. Decadence of ascorbic acid earnings both aerobic and anaerobic pathways and appertain to many factors such as oxygen, heat, light, storage temperature and storage time.

During juice processing, temperature and oxygen are the main factors responsible for vitamin C losses. Non-thermal processed juices retain higher levels of vitamin C.

Regarding packing material, vitamin C in fruit juice is quite stable when stored in metal or glass containers, whereas juice stored in plastic bottles has a much shorter shelf-life.

This water soluble vitamin contributes to many health benefits such as prevention of scurvy and cancer, relief from common cold, stimulate collagen synthesis and play a significant role in wound healing process. Deficiency of this vitamin in the body causes many diseases such as scurvy.
Vitamin C in citrus juice

Introduction to citrus juice

Citrus are non-climacteric fruits that are allowed to mature on the tree, since postharvest maturation will not occur. Among citrus juice, orange is by far the most important. Lemon, lime, grapefruit and tangerines are also processed as juice.

Like no other beverages, citrus juices do not suffer from any human intolerance, and therefore, it is suggested in the nutrition of population of any age. One of the characteristics of citrus juice is that it is to be consumed mainly as a cloudy drink.

After processing, the composition and quality of the citrus juices is affected strongly by the expression and finishing conditions, namely mechanical pressure shear and residence time.

Citrus juices are composed of more than 95% wt% water, and more than 100 different compounds. Sucrose, glucose, and fructose are the main components of the carbohydrate fraction which, along with other species such as citric acid, accounts for about 75-90% of the total soluble solids in juice.

Citrus fruits are an important source of antioxidants such as ascorbic acid, carotenoids, flavonoids, limonoids other phenolic compounds and also sugars, organic acids and amino acids, pectin, fiber, minerals and volatile components for human nutrition and quality of citrus juices.

Its color is caused by anthocyanins, their glucosides and condensation products, its taste by acids, sugars and phenolics and its aroma by a diverse mixture of volatile secondary metabolites in very low concentrations.

Citrus juice can be blend with other juices, or added spices or sugar prior to heating to make a beverage to meet local preferences in taste.
Introduction to citrus juice