UIPEVO – Ultrasonic Olive Oil Extractor for Higher Yields
- Hielscher’s UIPEVO is an ultrasonic extraction system to increase malaxation and extraction yield for extra virgin olive oil.
- The UIPEVO treats the olive paste mild and non-thermally with ultrasound resulting in higher yield and quality.
- Due to the gentle processing, all nutrients of the extra virgin olive oil are fully preserved.
Ultrasonic extraction is well known to increase yield, improve extract quality and to reduce extraction time – resulting in a more economical process. For olive oil, ultrasonic extraction has various advantages over conventional oil pressing: The ultrasonic treatment is a mild, non-thermal process. The ultrasonic malaxation and extraction is achieved by cavitation, a purely mechanical means.
By tuning the intensity of the ultrasonic malaxation and extraction can be adapted to the cultivar, olive fruits, and the desired flavour profile of the extra virgin olive oil. This allows e.g. to control the polyphenol content of the olive oil, which is responsible for the pungency and the shelf-life. Olive oil with high polyphenol content has a longer shelf life, but also a more intense flavour profile.
UIPEVO – Ultrasonic System for Extra Virgin Olive Oil Extraction
Hielscher’s UIPEVO is an industrial-grade ultrasonic extractor for the processing of extra virgin olive oil. The system is designed to meet the requirements of olive paste processing optimally. The advantages are a special designed sonotrode (ultrasound horn) which couples the ultrasonic waves into the olive paste. The precise control over all process parameters allows to fine-tune the process conditions and offers thereby the possibility to adapt the parameters to the olive paste and the targeted final product. This means that cultivars with mild flavour profile can be sonicated at higher intensity, whilst olives with a high polyphenol content might profit from a mild ultrasonic treatment to avoid a bitter taste. At the same time, the olive oil yield is maximized since the ultrasonic malaxation and extraction breaks the cell walls and releases the entrapped lipids.
Advantages of UIPEVO
- high-performance ultrasound
- easy and precise adjustment
- temperature control
- 24/7 operation
The UIPEVO is equipped with a high-power 4kW ultrasonic processor, a special malaxation sonotrode and flow cell. Depending on the process requirements and volume, the system can be easily clustered. The system can be easily installed by connecting hoses and a pump, which feeds the olive paste.
The digital control, automatic data recording (as CVS file on the integrated SD card), pre-programming, automatic frequency tuning and browser remote control make the UIPEVO a reliable and user-friendly system. The ultrasonic olive oil extrator UIPEVO can be easily cleaned by flushing with water or cleaning fluid under sonication – using the system as powerful ultrasonic cleaner (CIP/SIP).
The robustness of Hielscher’s ultrasonic equipment allows for 24/7 operation at heavy duty and in demanding environments.
- higher yield
- high quality
- rapid extraction
- adaptable to olive cultivars
- Agnese Taticchi, Roberto Selvaggini, Sonia Esposto, Beatrice Sordini, Gianluca Veneziani, Maurizio Servili (2019): Physicochemical characterization of virgin olive oil obtained using an T ultrasound-assisted extraction at an industrial scale: Influence of olive maturity index and malaxation time. Food Chemistry Volume 289, 15 August 2019, Pages 7-15.
- Servili M; Veneziani G.; Taticchi A.; Romaniello R.; Tamborrino A.; Leone A.(2019): Low-frequency, high-power ultrasound treatment at different pressures for olive paste: Effects on olive oil yield and quality. Ultrasonics Sonochemistry 59, 2019.
- Achat, S.; Rakotomanomana, N.; Tomao, V.; Madani, K.; Chibane, M.; Chemat, F.; Dangles, O. (2013): Enrichment of Olive Oil in Oleuropein by Ultrasound-Assisted Maceration and Antioxidant Activity. Abstract in Nutr & Metabol 2013.
- Bejaoui, M.A.; Beltran, G.; Aguilera, M.P.; Jimenez, A.; (2016): Continuous conditioning of olive paste by high power ultrasounds: Response surface methodology to predict temperature and its effect on oil yield and virgin olive oil (VOO) characteristics. LWT – Food Science and Technology 69, 2016. 175-184.
- Vossen, Paul (1998): Variety and Maturity the Two Largest Influences on Olive Oil Quality. Project Report. University of California, Davis, 1998.
Facts Worth Knowing
Olives and Olive Oil
Olives are the fruit crop of olive trees of the species Olea europaea, family Oleaceae. Olive oil is the liquid fat which is released from ripe olives by pressing the whole fruit. The composition and quality of olive oil is influenced by the cultivar, soil, altitude, harvest time and extraction process. The main component of olive oil is oleic acid (up to 83%), whilst other fatty acids such as linoleic acid (up to 21%) and palmitic acid (up to 20%) are present in smaller proportions.
Olive Oil Qualities
The most important quality criterion is its fatty acid composition, which is used to test quality and authenticity of the olive oil. The free oleic acid content is measured in weight percentage.
The texture and mouth feel of olive oil is determined by fatty acid composition. The fatty acids, sterols, methyl-sterols, and some alcohols are nonvolatile compounds which are not flavour-contributing compounds, but are very important for the rheology, mouth feel, and stability of the oil.
The actual flavour of the olive oil is mostly influenced by the volatile aromatic compounds such as aldehydes, ketones, esters, and organic acids.
Polyphenols (e.g. esters of tyrosol, hydroxytyrosol, oleocanthal and oleuropein), tocopherols, glucosides, aldehydes, ketones, esters, organic acids, aromatic hydrocarbons, and natural pigments like chlorophyll and the carotenoids are other compounds found in olive oil. Polyphenols, glucosides, and tocopherols are known for their antioxidative properties and are therefore nutritionally valued. Polyphenols and glucosides are responsible for the bitter, pungent flavour note of olive oil. Chlorophyll gives the the oil its green colour.
Virgin Olive Oils
If an oil is claimed as virgin, the oil was produced by mechanical extraction only (without any chemical treatment). This quality-related term “virgin” is differentiated into all Extra virgin, Virgin, Ordinary virgin and Lampante virgin olive oils.
Olive Oil Quality Standards
The International Olive Council has set the following quality standards for olive oil:
Extra virgin olive oil is the highest grade of virgin oil derived by cold mechanical extraction without use of solvents or refining methods. It contains no more than 0.8% free acidity, and has superior taste with some fruitiness and no defined sensory defects.
Virgin olive oil is a lesser grade of virgin oil, with free acidity of up to 1.5%, a good taste, but may show some sensory defects.
Refined olive oil is a type of virgin oil, which has been treated with charcoal, other chemical and/or physical filters. However, the glyceridic structure is not altered by this treatments. Its free acidity is not higher than 0.3% and its other characteristics correspond to those fixed for this category in this standard. It is obtained by refining virgin oils to eliminate high acidity or organoleptic defects.
Olive pomace oil is produced by refining pomace olive oil, which is often blended with some virgin oil to improve its flavour. Due to its high smoke point it is used as cooking oil.
The cultivar of Olea europaea L. is an important olive fruit species, which has manifold cultivars that differ in oil quality and flavour. The list below shows the most frequently used cultivars and their characteristics.
- Arbequina: Recognized for its aromatic ripe fruitiness, low bitterness, pungency, and stability
- Aglandau: Highly fruity, bitter, pungent, and stable
- Barnea: Fruity with mild bitterness, pungency, and stability
- Bosana: Highly fruity, herbaceous, medium pungency, bitterness, and stability
- Chemlali: Strongly aromatic fruitiness with notable varietal character
- Coratina: Strongly green herbaceous, bitter, pungent, and stable
- Cornicabra: Very fruity and aromatic with medium bitterness, pungency, and stability
- Empeltre: Mildly fruity with low bitterness, pungency, and stability
- Frantoio: Very fruity, aromatic, and herbaceous; medium bitterness and stability; strongly pungent
- Hojiblanca: Fruity, aromatic, mildly pungent, low bitterness and stability
- Koroneiki: Strongly fruity, herbaceous, and very stable; mild bitterness and pungency
- Lechin de Sevilla: Very fruity, mildly bitter, pungent, and stable
- Leccino: Medium fruitiness, and stability; low bitterness and pungency
- Manzanillo: Fruity, aromatic and herbaceous; medium bitterness and stability; strongly pungent
- Moraiolo: Very strongly fruity, herbaceous, and stable; medium bitterness and pungency
- Picudo: Very aromatic ripe fruitiness; medium pungency and stability; mildly bitter
- Picual: Controversial variety that when harvested early produces a nicely aromatic fruity oil that has medium bitterness and very high stability. Poor reputation is due to poor fruit handling.
- Picholine: Very fruity and aromatic; medium fruitiness, bitterness, and pungency
- Picholine Marocaine: Very fruity and aromatic; medium fruitiness, bitterness, and pungency
- Taggiasca: Mildly fruity; low bitterness, pungency, and stability
- Verdial de Huevar: Mildly fruity, bitter, and pungent; very green in color
(cf. Vossen 1998)