Preparation technology of dried longan

Abstract

The invention discloses a preparation technology of dried longan. The technology comprises the following steps: fruit picking, fresh keeping, fruit selecting, baking, grading, storing, and packaging. The technology achieves a pollution-free physical drying process in the production of dried longan. High quality anthracite is adopted as the heating raw material, the heating source and the baking room are separated, the residual gas after burning is discharged out of the room through a flue, the contact between the residual gas and the longan is avoided. The iron alloy with a high thermal capacity is indirectly heated by the heating source, then the high temperature iron alloy carries out heat exchange with air through the air supply circulation, then the heated air is introduced into a special U-shaped baking bed in a tunnel structure, the bed material is fully heated due to the complicated hydromechanics flow field structure, and thus the heat efficiency is improved. A constant temperature slow baking technology is adopted to guarantee the quality of dried longan. A thermocouple temperature measuring technology is adopted to monitor the temperatures of the bed body and the baking room in real time, the air flow amount in stove is timely adjusted at the same time, and thus the control and adjustment of temperature are realized.

Description

technical field [0001] The invention belongs to the technical field of dry fruit production, in particular to a process for producing dried longan fruit. Background technique [0002] Longan (hereinafter commonly referred to as "longan") originates in my country and is an important subtropical fruit in southern my country. The longan fruit is rich in nutrition, the flesh is fresh and tender, the juice is sweet, and the flavor is pleasant. However, longan is maturely harvested under high temperature and high humidity conditions from August to September, and the physiological and biochemical changes of the harvested fruit are severe. The fresh fruit is easy to change color and deteriorate, and it is not resistant to long-distance transportation and long-term storage. At a room temperature of about 28° C. during the harvest period, the fruits generally deteriorate and rot within a week. Because longan is not resistant to storage, except for a small part for fresh food, most o...

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Problems solved by technology

[0013] The purpose of the embodiments of the present invention is to provide a production process of longan dried fruit, which aims to solve the problem that the existing heat source dried fruit process cannot fully realize safety and environmental protection

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