First Commission Directive of 15 June 1971 establishing Community methods of analysis for the official control of feeding-stuffs (71/250/EEC) (repealed)

5.1. Preparation of the solution U.K.

According to the nature of the sample, prepare a solution as shown under 5.1.1, 5.1.2 or 5.1.3.

At the same time carry out a blank test omitting the sample to be analysed.

5.1.1. Samples free from organic matter U.K.

Weigh to the nearest mg a sample of not more than 10 g and containing not more than 3 g of chlorine in the form of chlorides. Place with 400 ml of water in a 500 ml volumetric flask at approximately 20 ^oC. Mix for thirty minutes in the tumbler, bring up to volume, homogenise and filter.

5.1.2. Samples containing organic matter, excluding the products listed under 5.1.3. U.K.

Weigh approximately 5 g of the sample to the nearest mg and place with 1 g of active carbon in a 500 ml volumetric flask. Add 400 ml of water at approximately 20 ^oC and 5 ml of Carrez solution I (3.7), stir then add 5 ml of Carrez solution II (3.8). Mix for thirty minutes in the tumbler, bring up to volume, homogenise and filter.

5.1.3. Cooked feeding-stuffs, flax cakes and flour, products rich in flax flour and other products rich in mucilage or in colloidal substances (for example, dextrinated starch) U.K.

Prepare the solution as described under 5.1.2 but do not filter. Decant (if necessary centrifuge), remove 100 ml of the supernatant liquid and transfer to a 200 ml measuring flask. Mix with acetone (3.6) and bring up to volume with this solvent, homogenise and filter.