Orange juice is the liquid extract of the fruit of the orange tree, produced by squeezing oranges. It comes in several different varieties, including blood orange, navel oranges, valencia orange, clementine, and tangerine.
What does ‘from concentrate’ mean?
At the manufacturing stage, when juice from oranges has been extracted and the pulp removed, the product is processed into two forms: not-from-concentrate (NFC) or bulk frozen concentrated orange juice (FCOJ). ‘From concentrate’ means that all the excess water from the oranges is removed, yielding a product seven times more concentrated than the initial juice. Compressing and then freezing the orange juice allows more efficient packaging and transportation. Water is then added in again before it is sold.
What does ‘Not From Concentrate’ mean?
For orange juice to be considered and labelled “not from concentrate,” it must be processed without any water removal and reconstitution. Juice not made from concentrate will likely be pasteurized, and it is also possible the juice producer will extract orange oil from the peel and add it to the juice to make the juice more flavourful.
Simple Orange Juice Ingredients
Orange: The primary ingredient is of course, oranges. Usually a blend of different types of oranges is used to give the juice a pleasant flavour free from bitterness. Selection of fruit is based on the breed and maturity and several other factors. Orange contains a large amount of sugars like sucrose, fructose, glucose; organic acids like citric, malic, tartaric acid and flavouring compounds such as esters, ketones, alcohols e.t.c.
Additives: Alpha tocopherol, EDTA, BHA and BHT are added as antioxidants. Corn syrup, dextrose, honey and some artificial sweeteners may be added for sweetness. Citric acid is also added to impart tartness. Nowadays, manufacturers fortify the orange juice with Vitamin C and Calcium (in the form of tri-calcium phosphate) to improve its overall nutritional profile.
Orange Juice Production Flow Chart
Industrial Orange Juice Production Video
The harvested fruit is inspected, graded and then passed along a conveyor where it is washed with a detergent to remove dirt and reduce the microbial load. The fruit is then rinsed and dried prior to extraction.
There are two automated extraction methods that are followed commonly in industry. In the first method, the fruit is placed 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 out through perforations in the tube wall. A water spray washes away the oil from the peel at the same time. This oil is reclaimed for later use as it contains limonene (promotes weight loss and prevents cancer). In the second method, 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. After extraction, the juice is filtered and then it can be chilled or concentrated depending on the product that is desired.
Concentration leads to extended shelf life of the juice and also reduces the storage and shipping costs. Juice is concentrated in the equipment called Thermally Accelerated Short-Time Evaporator (TASTE)which uses steam under pressure to heat the juice. The concentrated juice is transferred to a vacuum flash cooler which cools it to around 13 °C.
When a commercial package is to be prepared for retail sale, then the concentrate is taken and blended with water to achieve the desired properties like sugar to acid ratio, flavour and colour. Proper blending is essential for high quality product and that is why, this step is monitored carefully.
Although, the orange juice has an acidic pH (around 4) which prevents the growth of spoilage microorganisms naturally, but it still requires pasteurization to retard spoilage and inactivate enzymes that may cause undesirable changes in the final product. Several methods are used in the industry for pasteurization. Heating the juice at a temperature ranging from 85-94 °C for 30 seconds is adequate to reduce the microbial load.
Pasteurized juice is filled while still hot to ensure sterility. Metal or glass containers may be pre-heated prior to filling if possible. If the pre-heating is not possible, then the filling is done in a sterile environment. After filling, the containers are cooled as fast as possible, and then the orange juice is ready to be distributed.
What is the pH of Orange juice?
Fruit juice tends to have a low pH, which means it is acidic. Orange juice ranges in pH from 3.3 to 4.19. Acidic beverages can erode tooth enamel making cavities more likely, but certain minerals also affect the cavity-causing potential of fruit juices, according to a study published in the “Journal of the Indian Society of Pedodontics and Preventative Dentistry” in 2011.
What is pulp in orange juice?
The pulp of a citrus fruit is the stringy content of the fruit’s endocarp. The pulp contains the juice of the fruit. and is usually removed from fruit juice by filtering it out. The colour of the pulp can change, depending on the species and the ripening stage.
How long does orange juice last?
If not processed, freshly squeezed orange juice won’t even last few hours. Although, fresh and unprocessed juice can last for 2-3 days when refrigerated. Processed orange juice when packed in aseptic packages can last for 6-8 months at room temperature.
What colour is orange juice?
Orange juice usually varies between shades of orange and yellow, although some ruby red or blood orange varieties are a reddish-orange or even pinkish. This is due to different pigmentation in ruby red oranges. The blood orange is a mutant of the sweet orange.
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