Breweries regularly claim, therefore, as a marketing tool, that their beer is naturally brewed or, like the relatively new Steinlager Pure, that there are no additives or preservatives.
For a start, hops, which help to preserve a brew, are an additive rather than an essential component of brewing.
Secondly, most contain sulphites which are a natural by-product of fermentation. (Asthmatics lack an enzyme to break down these.)
Virtually any other additive is removed by modern filtration and is, anyway, harmless or even beneficial.
For example, potassium metasulphite preserves, but is also a healthy antioxidant. Ascorbic acid, otherwise known as vitamin C, helps to reduce haze in the beer.
Papain enzyme from the papaya fruit also helps to prevent haze (although it also destroys the head on a beer).
Propylene glycol alginate (from seaweed), used to stabilise salad dressings, also stabilises the head.
Amyloglucosidase is an enzyme that breaks down starch into sugar. Emkamalt is a food colouring.
Fermentation, which is conversion of sugar to alcohol, cannot start without sugar. There are five types: sucrose (table sugar from cane or beet), maltose (from barley), fructose (from fruit), lactose (in milk), glucose (in honey, for example) and dextrose (found mainly in cane syrup).
The brewing industry relies on the sugar (maltose) produced from sprouting barley.
However, corn sugar ferments the most rapidly and is used mainly to create fermentation in the bottle (like bottle-fermented sparkling wines); table sugar can boost alcohol content, and honey will impart a crisp sweetness.
Claims of purity are not new: Most German beers say, as a marketing tool, that they comply with the German Beer Purity Law which harks back to 1516 when only water, barley and hops were allowed in beer.
It was introduced at a time when medieval brewers were preserving theirs with soot, herbs such as stinging nettles or certain types of mushrooms.
The German purity law was honoured in the breach from the 1800s, however, when yeast became an integral part of brewing after Louis Pasteur discovered the micro-organisms that create fermentation. (Before that, brewers used sediment from a previous batch to ferment the next.)
The purity laws were changed in the mid-1990s to allow yeast, wheat malt (for wheat beers) and cane sugar.
The free trade agreement signed this month with China might encourage importation of more Chinese beer and be cause for concern: Some lower-quality Chinese brewers are believed to use formaldehyde (a cancer-causing element) to help break down barley to increase production
and to reduce haze in the beer. (It also destroys a lot of flavour.)
Finally, after all that, no research I have found concludes that anything in beer other than alcohol causes headaches the next morning.
Beer chocolate
Talking of additives, beer is being put in chocolates.
Auckland chocolate-maker Hanna Frederick settled, after trying several beers, on Monteith's Black and Speight's Old Dark to give a malt flavour to hers.
And I recall Old Dark in another chocolate which, I think, came from Invercargill. - Ric Oram
