18 Food analytics
Food fraud for centuries
Alcoholic beverages from Neolithic age to Present
Author: Erich Leitner, TU Graz, Institute of Analytical Chemistry and Food Chemistry, Stremayrgasse 9/2, 8010 Graz Austria
In the Neolithic period starting at around 11,500 BC in middle and
western Europe, there was a significant change in the way of living.
Formerly hunters-gatherers, humans then settled down and started to
raise animals while cultivating fruits and vegetables. This, incidentally,
is also the period when fermented alcoholic beverages were “invented”.
Archaeological evidence for alcohol production and use is usually associated
with fermenting domesticated species in agricultural societies around
the globe such as ancient Egypt, Mesopotamia, China and South America.
Recent excavations in Israel showed evidence of beer brewing in stone
mortars already dating back 13,000 years. The stone mortars contained
significant amounts of starch residues, which had typical morphological
changes and damages from the malting and fermentation process 1.
Chemical analyses of ancient organics absorbed into pottery jars
from the early Neolithic village of Jiahu in Henan province in China
revealed that a mixed fermented beverage of rice, honey and fruit
(hawthorn fruit and/or grape) was being produced as early as the seventh
millennium before Christ (B.C.) 2.
In Georgia in the South Caucasus region, Neolithic clay pottery
dating back to 5900 - 5500 BC was found 3. The large vessels served
as fermentation and storage tanks. Analysis of deposits on the inner
surface clearly proved the presence of fermented grapes.
Spectroscopic and chromatographic methods are valuable tools
for the investigations. Gas chromatographic techniques focus on volatiles
like fatty acids terpenes, while liquid chromatography with mass
spectroscopic detection is able to identify different organic acids like
tartaric, succinic, maleic and citric acid, which surprisingly survive
thousands of years in the pores of the clay vessels.
Illegal manipulation of alcoholic beverages
Food fraud is not a phenomenon of modern times; as soon as humankind
started to trade with food, illegal manipulations occurred. Already
the ancient Greeks and Romans had plenty of methods and additives to
“improve” the quality of the product. One obvious problem was oxidation
of beer and wine, as highly oxygen-permeable clay amphorae were commonly
used for storage. Coating the inside of the amphora with resins or
pitch should increase the shelf life of filled wine.
The Greeks added rose petals, violets or mint. Pliny the Elder mentions
such strange additions as asparagus, rue, sorb apples, mulberries,
Syrian carob pods (somewhat like chocolate), juniper berries, turnips,
roots of squills, cassia, cinnamon and saffron.
A much severer problem was the intentional addition of lead to wine,
to enhance the taste. The Romans realized that wine consumed from or
stored in lead vessels had a better taste and a longer shelf life. The reason
is the formation of lead acetate, having a sweet taste and due to biocidal
activity increasing the shelf life of the beverage. It was also a common
practice to boil grape juice in lead vessels for the production of sapa, used
to sweeten wine and food 4, 5.
Already in the Middle Ages, physicians clearly identified the source and
the symptoms of lead intoxication, leading to a ban of sapa in 1427 in France
and Spain. Indeed, in 1478, German authorities made wine adulteration a
crime punishable by death. Nevertheless, incidents with illegal lead addition
to fermented and distilled beverages are numerous even in modern times.
Lead is not the only heavy metal causing severe problems when
consuming alcoholic beverages. In the sixties of the last century, some
breweries in Canada and USA added cobalt sulfate to enhance beer
stability. The high dose of cobalt resulted in several fatalities 6.
Beside the above-mentioned frauds, there are still many ways to
counterfeit alcoholic beverages. They start with the addition of water,
Table 1: Chromatographic parameter Beer 1966