S.L. 437.63 Art. 6in 40% (V/V) values in compound 6.2. Starch S = total S' = optical V) ethanol N = weight saccharimeter 20° [ ] α D 6.3. The the same than 40% and 7. 7.1. If the calcium quantity of 7.2. In serum or (3.5). Fit a 50ºC for 30 7.3. feedingstuffs, content by - - - - - - - - 2.

Calculation of results The starch content (%) is calculated as following:

6.1. Measurement by polarimeter 2000(P - P') Starch content (%) = 20° [ ] α D

Where: P = total optical rotation in angle degrees

P' = optical rotation in angle degrees of the substances soluble ethanol

20° = specific optical rotation of pure starch. The numerical [ ] α D conventionally accepted for factor are the following

+ 185.9º: rice starch + 185.4º: potato starch + 184.6º: maize starch + 182.7º: wheat starch + 181.5º: barley starch + 181.3º: oat starch + 184.0º: other types of starch and starch mixtures feedingstuffs Measurement by saccharimeter

2000 (2N × 0,665) × (S - S') 26.6N × (S - S') × -content (%) = 20° 100 20° [ ] [ ] α α D D

optical rotation in saccharimeter degrees rotation in saccharimeter degrees of the substances soluble in 40% (V/

(g) of saccharose in 100 ml of water yielding an optical rotation of 100 degrees when measured using a 200 mm tube 16,29 g for the French saccharimeters 26,00 g for the German saccharimeters

20,00 g for mixed saccharimeters.

= specific optical rotation of pure starch (see 6.1)

Repeatability difference between the results of two parallel determinations carried out on sample must not exceed 0,4 in absolute value for a starch content lower 1,1% relative for starch contents equal or higher than 40% Observations sample contains more than 6% of carbonates, calculated in terms of carbonate, they must be destroyed by treatment with an exactly appropriate dilute sulphuric acid before determination of the total optical rotation. the case of products with high lactose content, such as powdered milk skimmed milk powder, proceed as follows after adding 80 ml of ethanol reflux condenser to the flask and immerse the latter in a water bath at minutes. Leave to cool and continue the analysis as indicated in 5.3.

Following feed materials, in case they are present in significant amount in are known to give rise to interferences when determining the starch polarimetric method and whereby incorrect results could be yielded: (sugar) beet products such as (sugar) beet pulp, (sugar) beet molasses, (sugar) beet pulp-molassed, (sugar) beet vinasse, (beet) sugar, citrus pulp, linseed; linseed expeller; linseed extracted, rape seed; rape seed expeller; rape seed extracted; rape seed hulls, sunflower seed; sunflower seed extracted; sunflower seed, partially decorticated, extracted, copra expeller; copra extracted, potato pulp, dehydrated yeast, products rich in inulin (e.g. chips and meal of Jerusalem artichokes); greaves. DETERMINATION OF CRUDE PROTEIN