| Lotus root drink is well received by consumers because of their unique flavor and fresh taste.The development of lotus root beverage can enhance the processing vslue. Fresh samples mainly are harvested in autumn and winter and easy to decay in strorage. Beverage consumption peak is in summer, so the lotus root beverage is under the seasonal restrictions of raw materials. Full lotus root powder as a semi-processed raw materials is made by fresh lotus root which is dehydrated and crushed, hence full lotus root powder preserve most of the nutrients. The characteristics and processing technologies of the full lotus root powder beverage were studied. The seasonal restriction of lotus root beverage was hoped to break. Extending the production time will bring economic benefits for the enterprise. Theoretical basis and production guidance of beverages made of full lotus root powder will be provided.First, nutrient content comparison between fresh lotus root and full lotus root powder was studied and full lotus root powder was found retaining the most nutrients including fat, peotein, starch et al. The gelatinization temperature of full lotus root powder under 70μm particle size was 57.08°C-67.8°C determined by laser diffraction and DSC techniques. Finally the gelatinization temperature of 70°C was carried out in heating process. Enzymatic hydrolysis process of full lotus root powder using the response surface methods was optimized to gain the best fungalamylase dose, temperature and time were 42 U/g, 53°C and 86 min. The turbidity of full lotus root powder solution decreased from 1082 NTU to 280NTU and the soluble solids rised to 3.75 Brix under optimum conditions,Secondly, the best beverage formula was established using fuzzy comprehensive evaluation method of senses: initial juice of the full lotus root powder 90%, white sugar 8%, citric acid 0.10% and honey 0.05%. The formula was level 6. Compound stabilizers added, were determined by single factor test and orthogonal design. Levels of composite stabilizer were determined as the carrageenan 0.02%,β-cyclodextrin 0.08%, sodium alginate 0.10% The sterilization process conditions: 95°C, 10min was established to meet the microbiological safety. Comparative study of flavor characteristic of fresh lotus root beverage and full lotus root powder one was done. by electronic nose and fuzzy comprehensive evaluation method Fresh lotus root beverage and full lotus root powder beverage were the same ratio in the additive case, similar flavor radar, 2, 6, 8, and sensors were corresponding to the flavor of the main substance and the response value was close. The levels were both 6 for fresh lotus root beverage and full lotus root powder beverage by fuzzy comprehensive evaluation method.Thirdly, the processing technology on compound beverage of full lotus root powder was preliminary inquired. Composite application of full-lotus root powder was dicussed in fruit and vegetable beverage. A kind of full-lotus root powder and chestnut mixed beverage was developed and the optimum formulation was gain: inital juice of full lotus root powder 61.9 % inital juice of chestnut 21.7%, sugar 7.3%, citric acid 0.06%; compound stabilizer: carrageenan0.05%, CMC-Na 0.05%, sodium alginate 0.10%.Finally, Suspension stability, flavor stability and color stability of Full lotus root powder beverage during 180 d were studied under the storage conditions of 4°C and 25°C. The changes of turbidity were smaller under 4°C storage condition, while at 25°C, the increasing trend was stable after 120 d. Stablity difference was less than 7. No visible precipitations and flocculations were in full lotus root powder beverage and suspension stability was stable. Sensory evaluation of flavor differences was less than 6% under 4°C storage condition and less than 10% at 25°C. Flavor was good. Color deterioration of Full lotus root powder beverage without color fixative was slow during storage. L values were decreased, while a, b values increases slowly. Tea polyphenols and ascorbic acid was less than L-cysteine on protecting color effect at the same dosage. 0.02‰L-cysteine can effectively maintain the color stability during the storage.
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