Improving the Olive Oil Yield and Quality Through Enzyme-Assisted Mechanical Extraction, Antioxidants and Packaging

Abstract

The present article investigates the use of different enzymes viz. pectinase, cellulase and pectinase CCM alone or in combinations to enhance olive oil recovery and quality. The enzymatic treatment significantly (P < 0.05) increased the oil yield and clarity of oil without adversely affecting the quality parameters. The combination of pectinase + cellulase (1:1) at 0.05% gave maximum oil recovery (11.0%), clarity (optical density = 0.242) and total phenols (165 mg/kg) compared with untreated samples. The oils showed increase in free fatty acid contents (0.82–2.95%), peroxide value (7.30–16.50 meq/kg), K232 (1.2–2.2), K270 (0.08–0.20) while decrease in iodine value (80.0–78.0) and total phenols (165–139 mg/kg) during 6 months of storage. The overall acceptability scores of oils packed in colored glass bottles with the addition of antioxidant tert-butyl hydroquinone were above 7.50 and placed in the category of “liked very much”. Practical Applications Olive oil is edible, containing essential vitamins, fatty acids and other natural elements of dietetic importance and is known for its anti-ulcer and plasma cholesterol lowering properties. Around ∼24% of the oil is not extractable using the existing oil extraction technologies and this part of oil either remains incorporated into the olive cake or lost in the effluent water. In this research, enzymatic treatments and different packaging materials were successfully used to enhance oil recovery and shelf life. The combination of pectinase + cellulase (1:1) gave maximum oil recovery while storage life enhanced up to 6 months under ambient conditions when oil packed in colored glass bottles with the addition of antioxidant tert-butyl hydroquinone. Therefore, the developed technology will help olive processors to extract more quality oil and also ensure the availability of oil for longer time.