Food Acidulants,Free Xanthan Gum,Guar Gum,Citric Acid Monohydrate Shanghai J.Shine Co.,Ltd , https://www.jshinechem.com
1. Appearance traits:
(1) Take a variety of volatile oils (turpentine, peppermint oil, clove oil, tangerine oil and cinnamon oil) to observe its color, whether it has a special aroma, and a spicy burning taste.
(2) Volatile: Take a small piece of filter paper dust, add a drop of peppermint oil, place it for 2 hours or slightly heat and observe the clear oil trace on the filter paper (control experiment with rapeseed oil).
(3) pH check: (detect free acid or phenols).
Take a drop of the sample and add 5 drops of ethanol, and check it with a wide pH test paper moistened with distilled water in advance. If it is acidic, it shows free acid or phenolic compound. The remaining sample ethanol solution is used for the following test (7) (8). .
(4) FeCl3 reaction (phenolic detection):
Take a drop of the sample, dissolve it in 1 ml of ethanol, add 1% to get 1~2 drops of FeCL3 alcohol solution, such as blue-violet or green, showing phenols.
(5) Benzoquinone test (test ketone, aldehyde)
Take 2~4-dinitrophenylhydrazine test solution 0.5~1ml, add 1 drop of sample-free aldol solution, shake vigorously. If there is ketone aldehyde compound, yellow-orange-red precipitate should be precipitated. If no reaction, it can be placed for 15min. Then observe it.
(6) Fluorescein test method:
The sample ethanol was dropped on the filter paper, sprayed with 0.05% fluorescein aqueous solution, and then wetted to expose the paper to 5% Br2/Col4 vapor. The hydrazine containing double bond (such as volatile oil) was yellow; the background changed quickly. It is light red.
(7) Fragrant aldehyde--concentrated sulfuric acid test:
A drop of volatile oil ethanol solution was applied to the filter paper, and a freshly prepared 0.5% vanillin aldehyde concentrated acetic acid solution was added to react in a yellow, brown, red or blue color.