02 Feb Microchem is now offering Olive Oil Analysis
Chemical analysis of extra virgin olive oil has proven to be fundamental indicators of sensory, quality, predictor of perishability, and authenticity of olive oils. Using the most advanced instruments available, and the most experienced and qualified team we can provide a comprehensive range of olive oil tests that are required for quality, authenticity and labelling purposes.
Microchem Lab Services is pleased to announce that we are able to perform the following analysis for the Olive Oil Industry.
Analysis on Offer:
Routine Chemical Analysis:
- Fatty Acid Methyl Ester Composition
- Total Fat
Newly Added Chemical Analysis:
- Free Fatty Acids
- Peroxide Value
- UV Determination
- Diacylglycerols (DAG)
- Pyropheophytins (PPP)
- Insoluble Impurities
- Commercial Sterility
- C. perfringens
- B. cereus
- Lactic Acid Bacteria
Free Fatty Acids (FFA):
FFA’s are formed due to the breakdown of triglycerides in oils during the extraction process. Fatty acids are free when they are no longer bound to any other molecules.
An elevated level of FFA can indicate poor quality of mishandled fruit, too much time between harvesting and extraction, poor storage and/or high temperature during extraction.
The FFA content is measured by the acid value which is a measure of the extent to which the triglycerides in the oil have been decomposed by lipase or another reaction. Rancidity is usually accompanied by FFA formation and the determination of FFA content is often used as a general indication of the condition and edibility of oils.
The analysis of olive oils at certain UV wavelengths can be used as a secondary measurement of rancidity in oil. Elevated levels of UV absorption indicate oxidised and/or poor quality oils, possibly due to the refining process and/or adulteration with refined oil.
Peroxide Value (PV):
Peroxides are primary oxidation products that are formed when oils are exposed to oxygen, causing defective flavours and odours.
Peroxide value is a primary indicator of rancidity in oil. Higher peroxide values indicate oxidized and/or poor quality oil and gives an idea of the freshness and storage of the oil.
Fatty Acid Methyl Ester Composition:
Fatty acid composition is a useful indicator of the purity of the olive oil; it could also indicate the presence of oils other than olive oil. High levels of trans fatty acids can indicate the presence of refined oils in an extra virgin olive oil.
The major fatty acid present in olive oil is Oleic Acid making up 55-85% of the oils’ fatty acid composition. Higher oleic acid or monounsaturated fat content will result in an increased durability and shelf life of olive oil.
This fatty acid composition combines all of the individual fatty acids to give a total fat value.
When the oil has been subjected to an increase in temperature, there is a breakdown in the triacylglyceride molecules. This breakdown causes diacylglycerols to be formed. In fresh extra virgin olive oil the level of 1,2 diacylglycerol is high, whereas oils that are made from unhealthy fruits or refined olive oil has a high 1,3 diacylglycerol level. The ratio between the 1,2- and 1,3-isomers is a useful marker for assessing oil freshness and degree of refining. The peak areas of 1,2- and 1,3-isomers are determined after silylation by gas chromatography. These peak areas are used to determine the % DAG content in the olive oil. The ratio of 1,2-diacylglycerols to the total diacylglycerols is a useful indicator of fruit quality and acts as a snapshot of olive oil freshness. Low values can indicate oxidized oil with sensory defects.
Olive oil has a pigment in it called chlorophyll. When oil is subjected to heat, thermal degradation of the chlorophyll may occur. The chlorophyll is broken down into pheophytins (PP) and further to pyropheophytins (PPP). The ratio of PPP to total PP is a useful indicator to distinguish between fresh, pure oils and oils that have undergone refinement, deodorizing or aging. These breakdown products are determined by high performance liquid chromatography using UV detection.
- Routine food microbiology analysis
- Foodborne pathogen analysis
- Water microbiological analysis
- Product shelf-life analysis
- Foreign object inspections
- Hygiene inspections and reports
- Microbiological swabbing
- Food chemistry
- Nutritional analysis
- Trace elemental and heavy metal analysis
- Food colorants (Azo Dyes)
- Vitamin analysis
- Water chemical analysis
- Melamine analysis
- Pesticide analysis
Our specialists provide consultation on the assessments and advice on environmental hygiene management programmes, interpretation of analytical results and advice on nutritional analysis, as well as assistance with pathogen management in production facilities.
Microchem is a South African National Accreditation System (SANAS) accredited laboratory that uses a quality system which meets national and international criteria (EN45001, ISO 17025). The analytical methods employed are based on nationally and internationally accepted standards.