Overview of vacuum freeze-drying of Brazilian berries:
Brazilian berries are usually freeze-dried not by directly freeze-drying the whole fruit, but by first making a pulp/puree tray for freeze-drying, followed by low-temperature crushing, sieving, and packaging. The entire production line can be planned according to the sequence of "pre-processing → pallet pre freezing → vacuum freeze-drying → crushing and packaging → quality inspection and warehousing".
Brazilian berry vacuum freeze-drying:
The main equipment control points of the process include raw material receiving and sorting, lifting machine, sorting platform, and stem removal machine to select purple black mature fruits, remove rotten fruits and impurities, and try to enter the processing, cleaning, sterilization, bubble cleaning machine, spray machine, ozone/hypochlorous acid water system within 48 hours after picking to remove sediment, microorganisms, and pesticide residues. Finally, clean water is used to rinse the specialized de nucleating and pulping machine, pulping screen, and filter machine for Brazilian berries. The Brazilian berry core is large and the flesh is thin. The fruit core needs to be separated first, and then fine fruit pulp can be obtained. The blending/homogenization blending tank, homogenizer, and low-temperature storage tank can control solid matter, viscosity, and oil dispersion; If making pure fruit powder, try not to add malt paste to the fabric of the fine plate/tray, food grade tray, quantitative filling machine, and fabric machine. The thickness of the fruit pulp spreading material is generally controlled at around 10-20mm. If it is too thick, it will prolong the freeze-drying cycle. The center temperature of the pre freezing section of the pre freezing freezer, spiral freezer, or in-situ freeze-drying machine usually needs to be lowered to below -35 ℃ to -40 ℃ to ensure complete freezing. The vacuum degree of the vacuum freeze-drying food freeze-drying machine, vacuum system, cold trap, and heating system is generally controlled at ≤ 50Pa. The material temperature in the sublimation stage should be lower than the melting point, and it can be raised to 30-45 ℃ in the analysis stage. The moisture content at the end point is usually ≤ 5%. It is recommended to control the relative humidity of the discharge environment in the low humidity discharge room, dehumidification system, Less than 40%, prevent freeze-dried powder from moisture regain, low-temperature crushing and sieving, low-temperature crusher, hammer crusher, vibrating screen Freeze dried chunks are first roughly crushed and then finely crushed. Common powder for drinking is 80-120 mesh. Baking or ingredients can be packaged with 40-60 mesh nitrogen filling packaging machine, aluminum foil bag/composite film packaging machine, metal detection machine. Acai berry oil and anthocyanin content are high. It is recommended to avoid light, isolate oxygen, nitrogen filling or vacuum packaging for quality inspection and storage moisture meter, colorimeter, etc HPLC、 Microbial testing and temperature controlled storage focus on detecting moisture, anthocyanins, total bacterial count, residual oxygen, and sealing; Store the finished product in a cool and dry place
Brazilian Berry Vacuum Freeze Drying Plan:
If exporting or producing high value-added functional food raw materials, it is recommended to make fixed process cards for the solid content, spreading thickness, pre freezing endpoint temperature, vacuum degree curve, analytical temperature, endpoint moisture, crushing mesh number, and packaging residual oxygen of Brazilian berry pulp. Acai berry has a high oil content and anthocyanins are easily oxidized. Low humidity packaging and dark storage in the later stage are more critical than freeze-drying many ordinary fruits and vegetables.