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Buyers often assume they mean much the same thing. In fact,
they are very different.  Sell-by and  display until dates are not
for the customer at all. They simply show shop staff when they
need to restock or reduce the price of an item.  Best-before dates
are for the benefit of the customer, and mean what they say. They
are only guidelines to tell you when the food will be at its best.
They are applied to foods that can safely be kept for some time
without any health risk. Once the best-before date has expired,
eating the food is not likely to do you any harm; it simply won t
be at its best. It s actually quite legal for a shop to sell food past
its best-before date, as long as it s fit for human consumption.
 Use-by dates, however, have legal force and are applied to
food that s highly perishable and could cause food poisoning if
kept too long. Meat, fish, ready meals, dairy products and fresh
juices must usually have a use-by date if they are sold packaged.
They don t have to if they are sold loose, though. There may also
be additional instructions, such as  consume within one day of
101 FACTS YOU SHOULD KNOW ABOUT FOOD " 141
opening . It s unsafe to eat food or drink past its use-by date even
if it smells and looks fine (unless it was frozen in plenty of time).
Surprisingly, there are no hard and fast rules about deciding
use-by dates. It s entirely up to those selling the food and applying
the labels to decide how long the food will last, and estimates
can vary. However, it s not in supermarkets interests to poison
their customers. Moreover, they can be prosecuted if there are
any bad failures. So when the dates are in the supermarkets con-
trol, they are genuinely fairly reliable  although with such vast
operations there s always the possibility of mistakes.
Problems are more likely to occur with packagers. It s illegal
for supermarkets to sell food past its use-by date. It s also illegal
for them to alter use-by dates so that it can be sold for longer.
This is not so for meat packagers. It s actually entirely legal for
a chicken-processing plant, for instance, to re-package and re-
date raw chicken and pass it off as fresh to the shops they sell
to. According to the trade union Unison, such re-dating is com-
mon practice. The worry is that once a processing plant starts to
re-date surplus chicken at the end of the day, it can quickly get
out of control. Chicken could be re-dated again and again with-
out anyone being aware of it.
142 " 101 FACTS YOU SHOULD KNOW ABOUT FOOD
77. The B vitamins are vital for the health of the
brain
he B vitamins are also sometimes called the thinking and
Tfeeling nutrients because they play such a vital role in nour-
ishing the nervous system. There are at least ten groups of them,
and they work in keeping the communication between nerve
cells up to speed. Many help form neurotransmitters. The vitamin
B6 pyridoxine is central to the making of the neurotransmitters
serotonin, dopamine and GABA. Vitamin B1, also known as thia-
mine, helps make the neurotransmitter acetylcholine, and when
B1 is low, so are levels of the neurotransmitters glutamate and
aspartate.
Shortages of B vitamins are linked to a lot of brain health
problems. Prolonged B1 shortage can lead to psychosis, and
maybe even reduced intelligence. B3 supplements can help mig-
raines and headaches, and have been used to treat schizophrenia.
B5 is sometimes known as the  anti-stress vitamin , because of its
role in controlling adrenalin. It s also thought to boost memory.
But the B vitamin that excites especial interest when it comes to
brain-ageing is B12, which helps form the myelin sheath that
insulates nerves.
Various studies have shown that people with Alzheimer s typ-
ically have reduced B12 levels, while from the other end, other
studies have shown that people with reduced B12 level are more
likely to develop the disease. The evidence is growing that B12
might protect you against Alzheimer s. It may even boost your
memory, though there s no hard evidence for that yet.
101 FACTS YOU SHOULD KNOW ABOUT FOOD " 143
What is interesting is that as we get older, we lose some of
our ability to absorb B12 from food  particularly if we use
antacids a lot or drink frequently. One in 200 elderly people lack
the gastric secretions necessary to absorb B12 altogether. If so,
their doctor may recommend they take B12 injections to make
up the deficit. Some doctors also recommend that adults over 50
eat food fortified with extra B12.
For most people, though, dietary B12 is enough. Indeed,
upping the B12 content of your diet can be enough to reverse
lapses in memory and slight problems with co-ordination and
balance. Sometimes, this just means eating plenty of fish, offal,
pork, eggs, cheese and milk. Because B12 needs folic acid to
work well, it s also worth eating foods rich in folic acid such as
bananas, oranges and lemons, green leafy vegetables and lentils.
" B1 (thiamine)  whole grain and enriched grain products like
bread, rice, pasta, fortified cereals, pasta and pork
" B5 (panthothenic acid)  meat, poultry, fish, whole-grained
cereals, legumes, milk, vegetables, fruit
" B6 (pyridoxine)  chicken, fish, pork, liver, kidney, plus whole-
grain cereals, nuts and legumes
" B12 (cyanocobalamin)  eggs, meat, fish, poultry, milk and
dairy products
" Folic acid  green leafy vegetables, bananas, oranges and
lemons, fortified cereals, cantaloupe, strawberries and lentils
144 " 101 FACTS YOU SHOULD KNOW ABOUT FOOD
78. Pre-washed salads are typically washed in
chlorine solution twenty times stronger than
that in a swimming pool
ales of salads in developed countries are almost double what
Sthey were a decade ago. It s not that we have become so
enamoured with healthy, low-calorie living that we are actually
eating that much more  rather that supermarkets have found
a way of adding value to this simplest and freshest of foods, by
providing it in pre-washed form. It seems a wonderfully con-
venient way of eating healthily.
When you see a salad inside its clear sealed plastic bag, you
might think that the bag contains just air and salad. In fact, it s
not air in the bag, but a modified form in which levels of oxygen
have been reduced from the normal 21% to just 3% and carbon
dioxide levels have been raised. Oyxgen is the gas that makes
fruit and vegetables go brown and limp after they are picked. So
reducing the oxygen keeps the salad fresh much longer. In fact,
salads kept in this modified-atmosphere packaging (MAP) can
stay looking fresh for up to a month.
Despite their apparent freshness, however, MAP wrapped
salads may not be quite as healthy as they look. Research by
Italian scientists at the Rome Institute of Food and Nutrition
suggests that MAP packed lettuces lose many of their nutrients.
Indeed, many of the antioxidant nutrients that make green salad
vegetables good for health, such as vitamins C and E and poly-
phenols, all seem to be reduced. The problem is not that the
MAP process actually robs salads of their nutrients; unwrapped
101 FACTS YOU SHOULD KNOW ABOUT FOOD " 145
salads also lose their nutrients quickly after they are picked. But
you can tell the nutrients are gone in an unwrapped salad
because it goes limp. With MAP, it stays looking fresh after its
nutrient value has diminished. [ Pobierz całość w formacie PDF ]

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