Y9 Food Tests PDF - IGCSE Biology CIE 0610
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These notes cover food tests, including tests for starch, reducing sugars, proteins, lipids and Vitamin C. The use of different reagents and expected results are detailed. Questions and answers are provided at the end to test understanding.
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IGCSE Biology- CIE 0610 Learn this! Notes Y9 Nutrition: Food Tests Testing for starch Use iodine solution (a carbohydrate) It starts off orange- brown and turns blue black in the presence of starch Testing for The Benedict’s test...
IGCSE Biology- CIE 0610 Learn this! Notes Y9 Nutrition: Food Tests Testing for starch Use iodine solution (a carbohydrate) It starts off orange- brown and turns blue black in the presence of starch Testing for The Benedict’s test. reducing sugars (carbohydrates) Add the solution and HEAT (800C) Glucose is a Starts off blue in colour. A brick red precipitate forms in the presence of lots of reducing sugar. reducing sugar (eg glucose). An orange precipitate forms if there is a little bit of reducing sugar present. Trace = a very small amount. Testing for The BIURET TEST. proteins - It starts off blue and turns purple in the presence of protein Testing for lipids The EMULSION TEST. - Add ethanol (alcohol). This is colourless to start off with - Turns cloudy/milky in the presence of lipids Testing for Vitamin The DCPIP test C - Add DCPIP. - It is blue to start off with. - It turns colourless in the presence of Vitamin C Test Yourself Q & A Questions Answer 1 Which reagent (solution) will you use to test for Iodine Solution starch? 2 What colour is iodine solution initially? Orange-brown 3 What colour will iodine solution turn if starch is Blue-black present? 4 Which reagent (solution) will you use to test for Biuret Reagent proteins? 5 What colour change are you looking for when testing Turquoise blue to Purple/Lilac/Mauve for the presence of proteins using the correct reagent? 6 Which reagent (solution) will you use to test for lipids? Ethanol 7 What result would indicate a positive result for the Solution turns cloudy white emulsion test for lipids? 8 Which reagent (solution) will you use to test for Benedict’s Solution/reagent reducing sugars? 9 Which colour would indicate the presence of a high Brick Red / Orange concentration of reducing sugars when using the correct reagent?
