Exam tip
In the exam, do not be tempted to use any previous knowledge you may have on a particular topic. You must always answer according to the information given in the text.
Questions 1-5
Complete the sentences below. Choose NO MORE THAN TWO WORDS OR NUMBERS from the text for each answer
i. A compound cannot be separated without energy and a
ii. Although mixtures consist of a combination of elements and compounds, it is possible for these to be
iii. If flavourings were not added, people would probably to consume margarine.
iv. Flavours can only be described as natural if they have a natural
v. Vanillin is chemically produced, but in chemical composition to a natural flavouring.
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Cupcakes are made from a mixture of
ingredients. Different flavoured cupcakes
have different mixtures. The icing used to
decorate the cakes contains sugar, water,
colouring and flavouring. Water and sugar
are different types of compounds. These
compounds are made from elements.
Elements, compounds and mixtures
Chemical substances occur in three
types.
- Elements - these contain one type of
atom only. They cannot be chemically
broken down into simpler substances.
- Compounds - these contain two or more
different elements bonded together. A
chemical reaction is needed to break up a
compound. This will involve energy.
- Mixtures - these may contain two or
more elements and/or compounds.
They are mixed in any proportion and
can be separated out.
When a baker mixes the flour, sugar, fat,
eggs, flavouring and colour together to
make cupcakes, he or she is making a
mixture. The icing sugar, water and colour
make a different mixture. The sugar and
water are compounds.
The compound water is made from the
elements hydrogen and oxygen. Sugar
contains the elements hydrogen, oxygen
and carbon.
In this unit, we will be looking at
flavourings, the substances that are added
to food or drink to give it a particular taste.
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They are added because people would
probably refuse to eat certain products
without them. Margarine and ice cream,
for example, would have unacceptable
tastes, whereas certain jellies, some other
sweets, and meat replacement products
would have little or no taste.
Natural flavours are those found in
nature. Those from vegetable sources
include vanilla, strawberry, lemon and
nuts. An example of an animal source
is beef flavouring, added for example to
chips. Essential oils and fruit juices can
also be used to flavour foods. They are
sourced in nature and obtained through
physical processes such as distillation and
fermentation.
Some animal flavours, such as bacon
and beef flavour in crisps, are vegetarian
because they are artificial rather than made
from animal sources.
There are also nature-identical
flavourings. An example is vanillin, which
is often produced cheaply from lignin, a
polymer, rather than from vanilla pods.
These flavourings are chemically identical
to natural flavourings, but have been
produced chemically rather than naturally,
e.g. by a process of chemical extraction.
The human body does not notice the
difference as their molecules are identical
to natural ones.
Artificial flavourings consist of
chemically synthesized compounds which
have no source whatsoever in nature.
Although the word natural has positive
connotations, some natural flavours may
have contaminated sources, which are
harmful. Artificial flavours undergo strict
testing because they are subject to laws
(e.g. The European Flavouring Regulation
(1334/2008) and may therefore be purer
and safer. Using natural flavourings is also
more expensive and may be considered
a waste at a time when we are trying to
preserve nature.
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