Food tests

• Test for starch - Add Iodine & it goes blue black
• Test for lipids- Emulsion test   * Process     * Dissolve lipid in alcohol     * Add water     * If emulsion forms lipids present
• Test for Protein - Biuret test   * Process     * Dissolve sample in water     * Add Biuret solution, if protein present it turns from blue to lilac
• Test for reducing sugars - Benedicts test   * Dissolve sample   * Add equal volume of benedicts solution   * Heat at > 60C for 5 Mins   * If reducing sugar present then it turns from blue to green/orange/brick red
• Test for a non reducing sugar - Basically just a longer Benedict's a standard Benedict’s test must be performed first and come back negative   * Then after Benedict’s test with a new sample;     * Dissolve sample in water     * Add equal volume of dilute HCl       * This hydrolyzes the bonds between dipeptides artificially     * Heat at >60C for 5 mins     * Neutralize it with Sodium bicarbonate until it stop fizzing     * Add equal volume of benedicts solution     * Heat at > 60C for 5 Mins     * If positive then it turns from blue to green/orange/brick red

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