A few generations ago, the nutritional benefits of beer were well
known. Beer was safer to drink than water and was thought of more
as a liquid bread and hence was a staple in the family's diet.
These days we buy foods without really knowing how they are made,
and this has changed our perception of which foods are healthy.
So where do the vitamins in beer come from? The key is that beer
isn't just made from cereal, its made from malted cereal.
Malting is a very simple process; seeds are soaked in water and
allowed to sprout. This is an ancient method for increasing the
nutritional content of seeds and quite likely originates in prehistoric
times. Sprouting may have happened initially by accident, but
our canny ancestors knew a good thing when they came across it!
As the seedling begins to germinate it actually makes vitamins.
Figure 1 gives a few examples of the types of increases in vitamins
seen after a few days of germination. For brewing, the major ingredient
is barley malt. A premium grade of barley will typically be germinated
for 4-5 days after first soaking in water. The maltster then stops
the germination process by drying in a kiln. The drying process
is gentle and thus preserves many of the vitamins, although some
less stable ones such as vitamin C are destroyed .The overall
result is a dried grain with a high vitamin content the barley
In the first stages of making beer, the malt is milled into a
flour, and then mixed with hot water. For beer making both the
bran and the flour are used, and so beer is a whole grain product.
Considering the vitamins only, at this point all of the vitamins
that can dissolve in water are released into the liquid. The result
is a vitamin enriched broth a liquid bread. Inevitably, some vitamins
will be lost during brewing and will not make it to the finished
product, as during fermentation, some vitamins will be used by
the yeast for growth. Despite this, several vitamins remain in
the beer by the time it gets to the bottle, and table 1 gives
some typical values which may be found in beer.
Folate in beer a BRI/EU project
In typical Western diets, vitamin deficiency is not generally
a problem. However, there's still room for improvement! For example,
the typical intake of folate is about 200 micrograms/day, but
nutritionists believe that our health would be improved by increasing
this figure to 300 microg./day. This is because over the last
ten years medical researchers have found that folates may help
protect against chronic diseases such as heart disease, cancer
Folates are found in fruit and vegetables, with the highest levels
being found in dark green leafy vegetables. Unfortunately, we
do not generally eat enough fruit and vegetables. Therefore, nutritionists
are focusing their attention on the nutritional value of some
commonly consumed folate-containing foods. This forms the basis
of a new EU project Folates, from food to functionality which
is being led by the Institute of Food Research at Norwich. Among
the foods being looked at are rye breads, orange juice, fermented
milk products, gazpacho and beer.
The BRI are participating in this project by measuring the levels
of folates in beer. Our initial results on the folate content
of beer are incorporated in Table 1; a litre of beer contains
between 10 to 45 % of the recommended daily intake (i.e. 20 to
90 microgr. of folate). To put this into context, one litre of
the highest folate beer contains approximately the same amount
of folate as 100g broccoli, 0.5 kg tomatoes, 0.25 kg potatoes
or 1.5 litres of 2% milk.
However, there is quite a variation in the levels of folate in
beer, due to differences in how these beers are made. The BRIs
part of the project will involve working out why there is such
variation, and to offer brewers guidelines on the best way to
preserve the folate in beer. For further details on the EU folate
project, please visit the website at www.ifr.bbsrc.ac.uk/folate/.
Folates are also known to help in the prevention of neural tube
defects, and pregnant women are consequently advised to increase
their intake of folates. It should be emphasised that since beer
contains alcohol, it is not a suitable dietary folate source for
Absorption of vitamins from beer
Nutritionists must always consider bioavailability that is our
ability to absorb nutrients from food. Even although a food may
contain quantities of a vitamin, it doesn't mean we can absorb
it. For example, researchers have shown vitamin A is more readily
absorbed from cooked carrots than raw ones i.e. boiled vegetables
may in some cases be more nutritious than their raw counterparts.
While this is a big hurrah for traditional British cooking techniques,
it still leaves the question of whether vitamins in other foods
can be absorbed.
In beer, the question of bioavailability has already been answered
in part. In a study at the TNO Nutrition and Food Research Institute,
in the Netherlands, a small group of volunteers were asked to
drink wine, beer, spirits or water with their evening meal for
three weeks (Van der Gaag et al 2000). The researchers checked
the volunteers blood at the end of this time and found that the
beer drinkers had bigger increases in the amount of vit.B6 in
their blood compared to those drinking the other beverages. This
result may have been expected, in that beer was the only one of
the beverages given to the volunteers which contained vitamin
B6! However, it does help to answer the question of whether we
can absorb this vitamin from beer.
In conclusion, culturally the knowledge that beer is made from
highly nutritious malt has been lost to the general public. Hopefully
new research will restore the image of beer to one that earlier
generations would recognise, and the message that moderate beer
consumption can make some positive contribution to a balanced
diet will be delivered.