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Wheat and Flour Testing Methods - WHEATFLOURBOOK.ORG

Wheat and Flour Testing Methods - WHEATFLOURBOOK.ORG

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Solvent Retention Capacity (SRC)<br />

Method<br />

1. Prepare four solvents: deionized water, 50 percent<br />

sucrose, 5 percent sodium carbonate, <strong>and</strong> 5 percent lactic<br />

acid.<br />

2. Weigh 5 grams of flour in a 50 milliliter conical bottom<br />

polypropylene centrifuge tube for mixing with each<br />

solvent.<br />

3. Add 25 grams of a solvent <strong>and</strong> cap tube.<br />

4. Shake vigorously for 5 seconds to suspend flour.<br />

5. Shake for 5 seconds at 5, 10, 15, <strong>and</strong> 20 minutes.<br />

6. Centrifuge for 15 minutes without braking.<br />

7. Invert tube <strong>and</strong> drain for 10 minutes.<br />

8. Weigh tube with residue.<br />

9. Repeat steps 2 through 8 for each solvent.<br />

Results<br />

• Solvent retention capacity (SRC) is the weight of solvent<br />

held by flour after centrifuging<br />

• SRC is expressed as percent of flour weight, on a<br />

14 percent moisture basis.<br />

• Four solvents are independently used to produce values<br />

for each solvent: water SRC, 50 percent sucrose SRC,<br />

5 percent sodium carbonate SRC, <strong>and</strong> 5 percent lactic<br />

acid SRC.<br />

Why is this important?<br />

Generally, lactic acid SRC is associated with gluten protein<br />

characteristics. Sodium carbonate SRC is related to levels of<br />

damaged starch <strong>and</strong> sucrose SRC with pentosan components.<br />

Water SRC is influenced by all water adsorbing components<br />

in flour. The combined pattern of these flour SRC results<br />

establishes a practical flour quality <strong>and</strong> functionality profile<br />

that is useful in predicting baking performance.<br />

<strong>Wheat</strong> <strong>and</strong> <strong>Flour</strong> <strong>Testing</strong> <strong>Methods</strong>: A Guide to Underst<strong>and</strong>ing <strong>Wheat</strong> <strong>and</strong> <strong>Flour</strong> Quality: Version 2

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