3B Scientific Experiment Set - On the Trail of Flavour Enhancers Brand new and topical-versatile in classroom situations - Manual (Page 5)

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manufacturers stopped using the pure additive (E620 ff) in their products, but use instead a mixture of
various amino acids or their salts. In many countries it is sufficient to list these ingredients as “spice”,
“yeast extract”, “fermented wheat” or the like on the label. Ultimately all these terms are „Trojan horses“
used to hide the fact that flavour enhancers were added to the product.
II. Components of the Kit
Extraction solution, 250 ml
L-glutamic acid, 20 mg
Ninhydrin, 300 mg
Filter papers, 20 pieces
Glass capillaries (volume 10 µl), 50 pieces
Chromatography foil, 20 pieces
Chromatography chamber, 5 pieces
III. Additional Equipment and Solutions Required
Erlenmeyer flasks, 100 ml
Mortar
Funnel
Tweezers
Bowl (glass or plastic)
Hair dryer, alternatively oven (105°C)
H
2
O dist., sterile
Disposable gloves (powder-free), suitable for laboratory work
IV. Preparation of Reagents
L-Glutamic Acid
Dissolve 20 mg glutamic acid in 20 ml sterile H
2
O (dist.). This gives a concentration of 1 mg/ml. This con-
centration can be further diluted to 1:3 or 1:5 to get standards with 0.33 or 0.2 mg/ml. The glutamic acid
standards should be stored frozen at –18°C in aliquots.
Plasticizer Medium
The plasticizer medium for thin layer chromatography is composed of butanol, acetic acid and H
2
O in the
ratio of 4:1:1.
Ninhydrin Solvent
The ninhydrin solvent (100 ml) is composed of 95 ml 2-propanol and 5 ml acetic acid.
Preparation of Ninhydrin
Dissolve 300 mg ninhydrin in 100 ml ninhydrin solvent. Please use a clean Erlenmeyer flask. The solution
can be stored in a closed bottle in the refrigerator.
Tracking Flavour Enhancers