Lugol’s Iodine Place a sample of the food in distilled water in a test tube. Add 3 drops of...
-
Upload
buck-mcdonald -
Category
Documents
-
view
212 -
download
0
Transcript of Lugol’s Iodine Place a sample of the food in distilled water in a test tube. Add 3 drops of...
![Page 1: Lugol’s Iodine Place a sample of the food in distilled water in a test tube. Add 3 drops of Lugol’s iodine in each test tube. Agitate sample and mix thoroughly.](https://reader036.fdocuments.us/reader036/viewer/2022072006/56649d135503460f949e7a33/html5/thumbnails/1.jpg)
Lugol’s Iodine
• Place a sample of the food in distilled water in a test tube.
• Add 3 drops of Lugol’s iodine in each test tube. Agitate sample and mix thoroughly.
• Observe color change– If starch is present, blue-black precipitate will form
![Page 2: Lugol’s Iodine Place a sample of the food in distilled water in a test tube. Add 3 drops of Lugol’s iodine in each test tube. Agitate sample and mix thoroughly.](https://reader036.fdocuments.us/reader036/viewer/2022072006/56649d135503460f949e7a33/html5/thumbnails/2.jpg)
Biuret Solution
• Add 40 drops of the test liquid• Add 3 drops of Biuret reagent solutions to
each test tube.• Shake gently to mix• Note color change
![Page 3: Lugol’s Iodine Place a sample of the food in distilled water in a test tube. Add 3 drops of Lugol’s iodine in each test tube. Agitate sample and mix thoroughly.](https://reader036.fdocuments.us/reader036/viewer/2022072006/56649d135503460f949e7a33/html5/thumbnails/3.jpg)
Sudan III stain
• In test tube add equal parts pf test liquid and water to the tube is half filled
• Add 3 drops of Sudan III stain to each test tube and shake gently to mix
• A red-stained oil layer will separate out and float on the water surface if fat is present.
![Page 4: Lugol’s Iodine Place a sample of the food in distilled water in a test tube. Add 3 drops of Lugol’s iodine in each test tube. Agitate sample and mix thoroughly.](https://reader036.fdocuments.us/reader036/viewer/2022072006/56649d135503460f949e7a33/html5/thumbnails/4.jpg)
Benedict’s Solution
• Add 40 drops of liquid to be tested• Add 10 drops of Benedict’s solution into each
test tube• Carefully heat the test tubes by suspending in
a hot water bath for 5 minutes• Note any color change
![Page 5: Lugol’s Iodine Place a sample of the food in distilled water in a test tube. Add 3 drops of Lugol’s iodine in each test tube. Agitate sample and mix thoroughly.](https://reader036.fdocuments.us/reader036/viewer/2022072006/56649d135503460f949e7a33/html5/thumbnails/5.jpg)
Benedict’s Solution