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The volume of water required varies between breweries, but is
generally about six and a half times the total volume of beer
produced. Additional water is expelled as effluent during the
generation of services, as water vapour from boiling and in the
spent hops and grain.
In order to be suitable as for use in brewing, water must be:
- Microbiologically pure (coliform bacteria are an indicator of
microbial purity and should be absent from a 100ml
sample).
- Clear and colourless (turbidity and colour can be caused by
suspended solids).
- Tasteless and odourless (chlorinated water can effect beer
flavour).
- Neutral pH (water should be neutral pH 7, or very slightly
acidic).
- Free from heavy metal ions (these should be absent from
brewing water. Different beers require specific mineral
ions).
Water composition can influence beer quality in three main
areas:
- Microbial contamination and beer spoilage;
- Mineral composition and pH;
- Organic compounds and flavour taints.
The brewer must ensure he controls these factors, and most
breweries will be obliged to carry out some from of water
treatment.
Many brewers draw their water from the municipal town supply
and hence have little control over its composition, especially
since many authorities draw their water form a number of
reservoirs which may lead to variations in water composition. In
the EC (European Community) all water supplied from the
water authorities is required to be suitable for drinking to a
standard speciffed by The European Council Directive
80/778/EEC; however, this does not mean it is of ideal quality
for brewing without further treatment.
Some brewers may draw their water from their own wells or
boreholes. The brewer then carries the responsibility to ensure
the water meets the EC standards and is suitable for brewing.
(1800)
21. Dietary antioxidants; nutrient and non-nutrient.
The human diet contains an array of different compounds that
possess antioxidant activities or have been suggested to
scavenge ROS (reactive oxygen species) based on their
structural properties. The most prominent representatives of
dietary antioxidants are ascorbate (vitamin C), tocopherols
(vitamin E), carotenoids, and flavonoids. Apart from vitamin C,
each group of these antioxidants consists of a number of
structurally different compounds; e.g. more than 600 different
carotenoids have been identified to date and about fifty of them
might occur in the human diet.
In the diet, there may be synergistic effects of these various
dietary compounds which are difficult to assess at present.
Indeed, the diet may be considered as an orchestra where
interactions between constituents may bring about effects which
are not the necessary properties of the individual constituents.
Vitamin C is considered to be one of the most powerful, least
toxic natural antioxidants. It is water-soluble and is found in
high concentrations in many tissues; human plasma contains
about 60 y.mol ascorbate/1. On interaction with ROS it is
oxidized to dehydro-ascorbate via the intermediate ascorbyl free
reservoirs which may lead to variations in water composition. In
The volume of water required varies between breweries, but is the EC (European Community) all water supplied from the
generally about six and a half times the total volume of beer water authorities is required to be suitable for drinking to a
produced. Additional water is expelled as effluent during the standard speciffed by The European Council Directive
generation of services, as water vapour from boiling and in the 80/778/EEC; however, this does not mean it is of ideal quality
spent hops and grain. for brewing without further treatment.
In order to be suitable as for use in brewing, water must be: Some brewers may draw their water from their own wells or
boreholes. The brewer then carries the responsibility to ensure
- Microbiologically pure (coliform bacteria are an indicator of the water meets the EC standards and is suitable for brewing.
microbial purity and should be absent from a 100ml (1800)
sample).
- Clear and colourless (turbidity and colour can be caused by 21. Dietary antioxidants; nutrient and non-nutrient.
suspended solids).
- Tasteless and odourless (chlorinated water can effect beer The human diet contains an array of different compounds that
flavour). possess antioxidant activities or have been suggested to
- Neutral pH (water should be neutral pH 7, or very slightly scavenge ROS (reactive oxygen species) based on their
acidic). structural properties. The most prominent representatives of
- Free from heavy metal ions (these should be absent from dietary antioxidants are ascorbate (vitamin C), tocopherols
brewing water. Different beers require specific mineral (vitamin E), carotenoids, and flavonoids. Apart from vitamin C,
ions). each group of these antioxidants consists of a number of
Water composition can influence beer quality in three main structurally different compounds; e.g. more than 600 different
areas: carotenoids have been identified to date and about fifty of them
- Microbial contamination and beer spoilage; might occur in the human diet.
- Mineral composition and pH; In the diet, there may be synergistic effects of these various
- Organic compounds and flavour taints. dietary compounds which are difficult to assess at present.
Indeed, the diet may be considered as an orchestra where
The brewer must ensure he controls these factors, and most interactions between constituents may bring about effects which
breweries will be obliged to carry out some from of water are not the necessary properties of the individual constituents.
treatment. Vitamin C is considered to be one of the most powerful, least
toxic natural antioxidants. It is water-soluble and is found in
Many brewers draw their water from the municipal town supply high concentrations in many tissues; human plasma contains
and hence have little control over its composition, especially about 60 y.mol ascorbate/1. On interaction with ROS it is
since many authorities draw their water form a number of oxidized to dehydro-ascorbate via the intermediate ascorbyl free
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