Unit 2 - Learning aim C: Chromatography
What were food color additives initially used for? - ANSWER To make food more
visually appealing to the consumer and mask poor quality.
Why were almost all of the original food color additives phased out? - ANSWER
Most were not safe for consumption and were being added to foods with no health
testing.
What could have been done to determine whether a color additive was harmful
before it was used in the food industry? - ANSWER They could have used
chromatography to determine the purity of each additive.
Of the original 695 color additives how many are still used today? - ANSWER 2
How many color additives total are used today? - ANSWER 7
What do all approved food dyes share in common? - ANSWER They are charged,
water-soluble organic compounds that bind to natural ionic and polar sites in large
food molecules.
What is the difference between absorption and adsorption - ANSWER Absorption is
a physical and chemical event occurring during contact between materials that have
an attraction for each other. Adsorption is different from absorption in that the
molecules of the material physically adhere to the adsorbent rather than being
absorbed into the interspaces of the absorbent material.
What is chromatography used for? - ANSWER To separate organic compounds for
identification or purification.
What are the two main components of chromatography? - ANSWER Adsorbent &
eluent
What is another name for the adsorbent? - ANSWER Stationary phase
(chromatography paper)
What is another name for the solvent or eluent? - ANSWER Mobile phase
What concept does chromatography work on? - ANSWER Compounds to be
separated are slightly soluble in the eluent and will spend some of the time in the
eluent and some of the time in the adsorbent.
What factors determine whether the separation by an eluent will be successful? -
ANSWER The affinity of a substance for the eluent versus the adsorbent allows
molecules to be separated by chromatography. (Depends on polarity)
What were food color additives initially used for? - ANSWER To make food more
visually appealing to the consumer and mask poor quality.
Why were almost all of the original food color additives phased out? - ANSWER
Most were not safe for consumption and were being added to foods with no health
testing.
What could have been done to determine whether a color additive was harmful
before it was used in the food industry? - ANSWER They could have used
chromatography to determine the purity of each additive.
Of the original 695 color additives how many are still used today? - ANSWER 2
How many color additives total are used today? - ANSWER 7
What do all approved food dyes share in common? - ANSWER They are charged,
water-soluble organic compounds that bind to natural ionic and polar sites in large
food molecules.
What is the difference between absorption and adsorption - ANSWER Absorption is
a physical and chemical event occurring during contact between materials that have
an attraction for each other. Adsorption is different from absorption in that the
molecules of the material physically adhere to the adsorbent rather than being
absorbed into the interspaces of the absorbent material.
What is chromatography used for? - ANSWER To separate organic compounds for
identification or purification.
What are the two main components of chromatography? - ANSWER Adsorbent &
eluent
What is another name for the adsorbent? - ANSWER Stationary phase
(chromatography paper)
What is another name for the solvent or eluent? - ANSWER Mobile phase
What concept does chromatography work on? - ANSWER Compounds to be
separated are slightly soluble in the eluent and will spend some of the time in the
eluent and some of the time in the adsorbent.
What factors determine whether the separation by an eluent will be successful? -
ANSWER The affinity of a substance for the eluent versus the adsorbent allows
molecules to be separated by chromatography. (Depends on polarity)