The coconut represents for most people holiday – beach, sea, sun and palm tree in a foreign exotic country. Besides, the tropical drupe is also a healthy all-rounder. The white, aromatic tasting fruit flesh is not only freshly edible, it can also be dried to chips and rasps. The high content of dietary fibre, omega-6- fatty acids and proteins makes coconut chips to a healthy snack alternative.
Before importing coconut to EU, regular food controls take place, because the fruit is grown and drying in tropical countries. As a result of incorrect storage or processing process, unwanted mould formation can occur, resulting in an excessively high mycotoxin concentration, which is highly regulated in food and feed stuff.
In order to comply with the high food standards, strict legal regulations for the permissible content of mycotoxins apply throughout the EU. If the content is too high, the goods will be rejected.
Clean-up of Ochratoxin A in Food and Feed
The challenge many laboratories have to face nowadays is to be able to process many samples as quickly as possible. To facilitate this, LCTech has developed the 3 cm OtaCLEAN SMART columns in addition to the 3 mL OtaCLEAN immunoaffinity columns.
OtaCLEAN SMART columns convince not only by their small size and a lower price, but also by a reduced solvent consumption, shorter processing time and excellent recovery rates in comparison to the 3 mL columns. Both columns have a very high matrix tolerance and are able to bind ochratoxin A highly specifically. They are suitable for both, manual and automated processing, e.g. with the LCTech robotic system FREESTYLE SPE or the FREESTYLE ThermELUTE™.
Homogenise 20 g of coconut chips and add 2 g of sodium chloride. Extract the mixture through 50 mL of methanol / water (80/20 (v/v)) and add 50 mL of n-hexane in order to remove fat and essential oils. To ensure high extraction efficiencies, continue the extraction for at least 10 minutes.
Filtrate the raw extract and dilute 2 mL of the n-hexne freephase with 12 mL PBS (contains 8% Tween20). Load 14 mL sample onto an OtaCLEAN immunoaffinity column and wash the column afterwards with 10 mL of deionized water. Dry the column by a short air flush.
Elute the toxin with 2 mL of methanol. Keep the column bed incubated with methanol for 5 minutes in order to ensure a fully denaturation of the antibodies.
By using the OtaCLEAN SMART column, load 2.8 mL sample onto the column. Wash the column afterwards with 2 mL of deionized water and dry it by flushing air through it. For the SMART column, elute Ochratoxin A with 400 µL methanol.
Keep the column bed incubated with methanol for 5 minutes to ensure a fully denaturation of the antibodies.