Automation-ready Weighing for Olive Oil Quality Control

Several METTLER TOLEDO balances, including a NewClassic MS303S, are in use for testing samples of raw and processed olive oil in the quality control laboratory of a large, family-run, trading and processing company in the Italian province of Tuscany.

Extra-virgin olive oil from producers around the Mediterranean arrives in bulk quantities at the company’s facility in the hills outside Siena. It is stored in an automated tank farm from where the filtered and blended product is shipped to customers (primarily oil refineries and industrial consumers).

Quality control is important at both ends of the company’s value chain. Incoming deliveries need checking for contaminants and, especially, excessive water, which tends to make the oil go bad and shortens the life of the plant’s de-moisturizing filters. Should a consignment of oil contain more than 0.3% water, compensation can be claimed from the producer for failure to deliver adequate purity so analysis also has a commercial impact. The outgoing product must also comply with Italian and EU regulations in order to ensure that customers get what they pay for. Around 25 samples a day are taken from incoming oil deliveries and processed product and analyzed for acidity, peroxide, fatty acids and extraneous organic compounds depending on how the oil will be used.

These samples are taken to the company’s small, but well equipped, on-site laboratory including gas and liquid chromatographs with automated sample changers, a mass spectrometer and a spectrophotometer. Weighing is performed by several METTLER TOLEDO balances, including the NewClassic MS303S. This precision model offers a winning combination of strong performance and increased productivity thanks to a fast settling time, consistently reliable results and assisted by proven MonoBloc weighing technology and FACT (fully automatic time- and temperature-controlled internal adjustment). Ease of cleaning can mean a great deal in this application as spilled olive oil is messy stuff. The MS303S has a streamlined, easily wiped and oil-resistant housing with IP54 in use protection to stop liquids from penetrating the instrument. The high contrast display (HCD) with big numbers and clear symbols is an asset in this lab where results from all the instruments are still entered into a database manually. Greater automation is a future possibility and the company is considering investing in a laboratory information management system (LIMS). RS-232 and USB ports are standard equipment on the MS303S, so sending weighing results to the LIMS will be easy and straightforward when that time comes.