Research progress on drying technology of green leafy vegetables
Abstract: Spinach, coriander and celery are favored by the masses as nutritious green leafy vegetables. Taking the above three kinds of green leafy vegetables as examples, the working principle, technical characteristics, research status and development trend of green leaf vegetable drying industry were introduced, aiming at providing reference for the development of green leaf vegetable drying industry.
Key words: green leafy vegetables; microwave drying equipment; research status
Green leafy vegetables are a kind of common fast-growing vegetables. There are more than 10 families of green leafy vegetables cultivated in China, more than 30 species, various kinds, rich in nutrients, rich in vitamins, β-carotene, minerals and dietary fiber. It can promote gastrointestinal motility and prevent osteoporosis and diseases such as hypertension, coronary heart disease and diabetes.
Chinese nutritionists point out that the daily intake of vegetables per person should be (400~500)g, of which more than 200g should be green leafy vegetables. Green leafy vegetables are essential for humans. However, green leafy vegetables are not resistant to storage after harvesting, and the nitrates in green leafy vegetables that have been stored for a long time are converted into nitrite. If not treated in time, it will not only be harmful to human health, but also cause huge economic losses.
Drying is a common food processing technology. By drying, the water content of green leafy vegetables can be reduced, the concentration of soluble substances in green leafy vegetables can be increased, microbial growth and enzyme activity in green leafy vegetables can be inhibited, and green leafy vegetables can be preserved for a long time and transported easily. And carry. This paper reviews the working principle, technical characteristics, research status and development trend of green leaf vegetable drying technology, aiming to provide reference for the development of green leaf vegetable drying industry.
Research Status of Drying Technology of Green Leaf Vegetables
At present, the main technologies used in the drying and processing of green leafy vegetables are
Solar drying, hot air drying, microwave drying, vacuum drying, and vacuum freeze drying.