Design of automatic control system for the precipitation of bromelain from the extract of pineapple wastes

Food Science and Technology (Campinas)

Flavio Vasconcelos Da Silva¹  Regina Lúcia De Andrade Dos Santos¹  Tatiana Lie Fujiki¹  Manuela Souza Leite¹  Ana Maria Frattini Fileti¹ 

[1] ,Universidade Estadual de Campinas Faculdade de Engenharia Química Departamento de Engenharia de Sistemas QuímicosCampinas SP ,Brasil

关键词: bromelain;    PID Controllers;    fieldbus;    bromelina;    controladores PID;    fieldbus;   

DOI  :  10.1590/S0101-20612010000400031

来源: SciELO

【 摘 要 】

In this work, bromelain was recovered from ground pineapple stem and rind by means of precipitation with alcohol at low temperature. Bromelain is the name of a group of powerful protein-digesting, or proteolytic, enzymes that are particularly useful for reducing muscle and tissue inflammation and as a digestive aid. Temperature control is crucial to avoid irreversible protein denaturation and consequently to improve the quality of the enzyme recovered. The process was carried out alternatively in two fed-batch pilot tanks: a glass tank and a stainless steel tank. Aliquots containing 100 mL of pineapple aqueous extract were fed into the tank. Inside the jacketed tank, the protein was exposed to unsteady operating conditions during the addition of the precipitating agent (ethanol 99.5%) because the dilution ratio "aqueous extract to ethanol" and heat transfer area changed. The coolant flow rate was manipulated through a variable speed pump. Fine tuned conventional and adaptive PID controllers were on-line implemented using a fieldbus digital control system. The processing performance efficiency was enhanced and so was the quality (enzyme activity) of the product.

【 授权许可】

CC BY   
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