1. Longan and litchi fruit are widely cultivated in southern China, Southeast Asia and South Asia, they contain a core, pulp and peel. Among them, the fruit pulp is about 50%, the fruit core is about 40%, and the fruit peel is about 10%.
2. Longan fruit is rich in nutrients and is a famous tropical characteristic fruit for both food and medicine.. It has the functions of lowering blood sugar, enhancing immunity, anti-oxidation and anti-aging. Apart from its great taste, litchi pulp has been found to be rich in nutrients including vitamin C, polysaccharides and many types of minerals
3. Fresh longan and litchi fruits are prone to spoilage, discoloration, short shelf life, and are difficult to store, transport and keep fresh. Therefore, there is a great demand for longan and litchi processing equipment in the market. Currently, the main processing methods of litchi and longan are drying, juice making, canning and fermentation to make into dried fruit, juice, fruit wine or fruit vinegar and canned products. The litchi/longan processing line is mainly composed of longan and lychee washing machine, selection machine, longan and lychee peeling and pitting machine, longan or lychee meat dryer, longan and lychee pulp beating machine, juice enzymatic clarification equipment, homogenization, sterilization and filling Equipment.
4. The capacity of longan/litchi processing equipment ranges from 20T/D to 500T/D for customers to choose from. And the end products can be filled into bottles, pouches, metal cans or cartons.
5. The material of the litchi/ longan processing machine is made of food-grade SUS304 material, which can guarantee to produce premium quality end products.
6. The whole longan/litchi processing line is fully automatic and controlled by PLC, with the feature of high automation, high efficiency.
7. The production line equipment is specially designed and customized according to the characteristics of litchi and longan, high yield rate and energy saving.

Dry litchi/longan pulp: Fresh litchi or longan through washing, sorting, peeling and pitting process, then use the belt dryer or heat pump dryer to dry the fruit pulp from 70%-80% moisture to less than 18% and have a very high sugar content of 60◦–65◦Brix. Then the end products can be filled into pouches or plastic jars. The drying temperature is recommended with 70◦–80◦C with 40–48 hours drying period for producing high-quality dried longan or litchi.

Litchi/Longan juice: longan or Lychee juice has large amounts of sugars, acids, vitamins, minerals and aroma compounds. The single-strength juice(15Brix) or concentrated juice(60Brix) can be produced, and the end juice can be filled into aseptic bags, bottles, cans or aseptic cartons.

Canned litchi/longan products: Fresh litchi or longan after washing, grading, peeling and pitting, then filled into the fruit pulp into metal cans with syrup.

Fruit is washed with clean water, then soaked for 5 min in 0.1% potassium permanganate solution as a disinfectant treatment, and are finally rinsed with flowing, clean water for 5 min. Immersion operations should be done carefully to prevent fruit bursts. The washing process is completed by a bubble washing machine and brush washing machine.

To maintain fruit quality, it is suggested to transport fresh lychee and longan fruit to the processing plant within 24 hours of harvest. After the grading, small fruit or fruit with browning, soft rot, or broken skin surfaces should be removed. The sorting process is done manually through roller conveyors.

When the lychee/longan peeling machine is used, the production efficiency is very high, and the peeling rate can reach more than 99%. It is an ideal choice for the juice and fruit wine industry. After the treatment of the equipment, the peel and pulp of litchi/longan can be separated. Lychee/longan peeling machine when used are relatively large output, good peeling and core removal effects. The integrity of the lychee pulp treated by the equipment is maintained very well, and it is almost undamaged.

Lychee/longan fruits are passed through tube or small head by slightly turning to obtain a good separation of flesh and stone. Along with rotation of the rubber wheel, a feeding wheel pushes fruit to the surface of oriented strips to be cut by knives, which are fixed on a knife shelf one by one. Lychee/longan stone is separated from the flesh by a plunger-type knife and falls into a vibratory disposal chute. Last, an output wheel for rind takes the rind out of the machine. For better quality, it is important to maintain the integrity of the flesh well.

The major processed product of lychee fruit is “canned in syrup.” The lychee industry has established production procedures for canned lychee. According to the quality standards, cans must be precleaned first either by steam or boiling water. Sugar syrup of 30◦Brix concentration is prepared in hot water, which is then brought to boiling temperature kept for 1 min. Peeled lychees are filled into cans at predetermined weight for the proper can size and hot syrup is poured over, leaving 1/4 inch (∼6 mm) headspace. The syrup should be poured at a temperature not lower than 75◦C with the addition of 0.25% citric acid in the syrup to preserve fruit color. Cans with fruit and syrup are then passed through an exhaust box (to remove any trapped gases) maintained at 75◦–80◦C using steam as a heating medium. The exhaust operation takes 5–6 min, following which cans are sealed immediately. Cans are then thermally processed in a commercial retort at a temperature range of 116◦–121◦C for 15–20 min. At the end of the thermal treatment, cans should be cooled immediately to around 35℃.

the production of dried lychee/longan fruit is described as follows: fruit selection → washing → grading → baking → packaging → storage. It is important to choose an appropriate cultivar with large and round shape fruits with thick and even skin and high dry matter content and sweet taste but low astringency. Lychee drying is a three-stage process: (1) it starts at a high temperature of 65◦–70◦C, with turning the fruits every 2–3 hours. After 24 hours at this temperature, fruits are bagged and stored for 2–3 days at room temperature. (2) The second stage of drying is at a temperature of 55◦–65◦C for 10–12 hours, with turning the fruits every 2–3 hours. After the second stage, fruits are usually stored for 3–5 days. (3) The final drying is at a temperature of 45◦–50◦C for 8−10 hours.

Longan/Litchi after peeling and pitting, we will obtain the fruit pulp, the fruit pulp will be sent into the beating machine. Under the rotor and paddle force, the pulp will get extracted, the fine pulp will go to the pulp receiving hopper through a sieve screen, and the coarse texture and other big solids pomace will be filtered and discharged.

The enzymatic hydrolysis process of litchi or longan pulp, add 0.045%-0.05% pectinase into the enzymatic hydrolysis tank, heat the litchi or longan pulp to 46-50℃, turn on the mixer, the reaction time lasts 2-2.5 hours, and the juice yield can reach 90%.

Pasteurization is one of the most popular methods used to preserve longan/lychee juice, but thermal processing usually impairs the transparency of such juice due to brown turbidity. Browning not only reduces the visual quality but also results in undesirable changes in flavor and loss of nutrients. Hence, a non-thermal process such as HPP pasteurizer is an alternative for preserving color, flavor and nutrients, High pressure (100-900 MPa/1-2 min) causes microbial and enzyme inactivation to enhance safety and shelf-life of perishable foods, with minimal effects on nutritional and quality parameters.

For longan/litchi single strength pulp and concentrated pulp, we can use the tubular sterilizer to do the heat treatment. And the sterilizing process is 125℃ for 10-15S.