An Innovative Strategy of Comprehensive Utilization of Tiger Nuts (Cyperus esculentus L.): Simultaneous Extraction of Oil and Glucose Syrup by Amylolysis-Assisted Aqueous Extraction Process

The tiger nut (Cyperus esculentus L.) possesses a substantial nutrition yet its industrialization process is characterized by sluggishness. Herein, we introduced a green approach to achieve simultaneous extraction of oil and glucose syrup from tiger nuts via an amylolysis-assisted aqueous extraction process (AAEP). Briefly, tiger nut flour was rinsed with fivefold distilled water for 1 h to eliminate non-starch polysaccharides and separate the majority of the oil (64.02%). Subsequently, liquefaction was conducted using α-amylase (AMY), followed by saccharification employing amyloglucosidase (AMG) and pullulanase. The operating conditions of amylolysis were optimized which include enzyme dosage and time of liquefaction and saccharification. Eventually, the final yield of oil and glucose syrup reached 89.84% and 89.41%, respectively. Confocal laser scanning microscopy (CLSM) results demonstrated that starch hydrolysis promoted the release of encapsulated oil, which enhanced the extraction efficiency of oil. Overall, our findings highlight that AAEP is an effective industrial approach facilitating comprehensive utilization of tiger nuts.