How Orval beer is made...

When a person enjoys a beer at the pub counter or at home, he probably does not imagine how complex the process of brewing beer is.

Well before the brewer gets down to his task, the earth, with a little help from farmers, yields a harvest of barley and hops. The region and the prevailing climatic conditions during the cultivation of these two plants have an important impact on the method that the brewer will use to make his beer.

During this time, the different geological strata of the subsoil shape the water that will be used to prepare the beer. Once the harvest has been completed, the barley will be prepared by the malters, according to the brewer's specifications. The hops will be dried first, then packaged as such or after they have been turned into pellets or extracts - for it is in the latter two forms that hops can be best preserved in time. Although a cocktail of cooking, chemistry and biology, beer brewing also demands rigorous techniques.

In the succession of delicate operations, one finds two principal stages. First of all there is the malting, then the actual brewing. We also discover some of the ingredients which make each type of beer a special sort : water, malt, sugar and hops.

Five operations are generally necessary for brewing beer :

1. in the first place, a source of starch, generally a barley malt;
2. the malt grains are then ground into flour to liberate the starch;
3. this starch is then transformed into simple sugars;
4. yeast is added to transform the sugars into alcohol;
5. then, at wish, the liquid is left to rest and then finally filtered.

At the end of this chain of operations, beer is obtained : sweet or bitter; clear or dark; cloudy or clear or sparkling; higher or lower alcohol content. That is the basic recipe used by brewers the world over.

BREWING

Malt differs from barley by its flakiness, its slightly sweet taste, its aroma, more or less caramel-flavour, and its colour. To produce Orval beer, we use a pale malt and a small proportion of caramel malt. Inaugurated in August 2007, the new brewing hall is really at the cutting edge of new technologies, developed by a German manufacturer in cooperation with Orval brewery and a Belgian university.

Stored in concrete silos, the malt is first cleaned to remove impurities and then crushed using what is known as the wet milling method. During this operation, water from the Mathilde fountain is injected in the crusher at a temperature of 65°C (149°F). This method releases the starch contained in the grains, while retaining optimally the husks that will be used as filtering support. From the crusher, the mash is pumped directly into two newly installed filtering tanks, instead of passing through a mashing vat first. This method was selected when designing the new brewing hall, so as to comply with the English infusion brewing tradition. During mashing, the mixture of previously crushed malt and water from the Mathilde Spring is continuously stirred. In the past, the brewer used a rake to carry out this operation. Throughout the entire process, the brewer closely monitors the temperature of the mash

Thanks to the action of these lauter tuns, a sweet wort is obtained within a few hours. The wort is then transferred to the boiling kettle, where it is sterilized and flavored with fine hops of German and Slovenian origin. After about one hour, an amber-coloured wort is produced. During this process, the water vapour generated by boiling is condensed through a heat exchanger. The recovered energy is stored in a 35 m³ water tank. This energy, stored as hot water at 99°C (210°F), is used to preheat the wort before boiling. This system makes it possible to save approximately 40% of the energy required.

As the wort is sterile when it leaves the boiling kettle, great care must be taken to prevent contamination. This sweet liquid is indeed an ideal breeding ground for bacteria. The boiling wort is therefore cooled very rapidly, protected from contact with the air, in a plate heat exchanger before being transferred to the fermentation tanks.

FIRST FERMENTATION 

The cooled wort is transferred to cylindroconical fermentation tanks, where it is inoculated with a starter prepared from a pure yeast culture. In 1830, yeasts were identified as being responsible for fermentation. These microorganisms were first isolated by the German biochemist Mayer, who named them Saccharomyces, the scientific term meaning “sugar fungus”.

After Pasteur, the Danish scientist Hansen succeeded in isolating pure yeasts for low-temperature fermentation, followed by the so-called top-fermenting yeasts. At the Orval Brewery, a very specific yeast strain is used.

Once inoculated, the wort ferments vigorously until it reaches an alcohol content of 6.2%. The primary fermentation lasts four to five days. During this process, the yeasts work at temperatures ranging from 15°C to 23°C and, towards the end of fermentation, rise to the surface of the beer along with the foam.

MATURATION 

Once fermentation is complete, the young beer, still cloudy at this stage, is transferred to conditioning tanks. The conditioning period lasts two to three weeks at a temperature of 15°C. It is in these tanks that different hop varieties (in pellet form) are added to develop the subtle aromas that characterize Orval.

Wild yeasts (Brettanomyces) are also added at this stage. Carefully preserved in the laboratory of the Orval Brewery, these yeasts continue to develop during the subsequent stages of production, giving Orval beer its distinctive, slightly tart and remarkably unique character.

Although hops were introduced relatively late among the flavouring ingredients used in brewing, they are a plant with many applications. Hops are well known for their medicinal uses, but it is the brewing industry that has made them an important industrial crop. The most renowned varieties include Bavarian Hallertau, Slovenian Styrian Golding and Alsatian Strisselspalt. These hops are used to impart the distinctive aroma and flavour of Orval beer.

BOTTLING 

Before bottling, the beer is centrifuged to remove dead yeast cells and suspended hop particles. During this operation, liquid candi sugar and fresh yeast are added and carefully dosed to prepare the beer for bottle refermentation.

The bottling process includes the cleaning and inspection of bottles (new or returnable) and crates, as well as filling the bottles with beer, applying the labels, and packing them into crates before the final stage of bottle refermentation takes place.

REFERMENTATION IN THE BOTTLE 

For approximately 3 to 5 weeks, Orval beer undergoes bottle refermentation in climate-controlled storage rooms maintained at 15°C. This process is similar to the primary fermentation. The carbon dioxide produced during fermentation saturates the beer, contributing to its natural effervescence and the formation of its rich, creamy head.

LAB CHECKS & QUALITY 

The Orval Brewery and Cheese Dairy would not be able to offer products of such high quality without the precise and rigorous work of the quality control team. From the inspection of raw materials to the finished product, every stage of production is strictly monitored, measured, verified and validated in the laboratory.

Particular attention is also devoted to the control and propagation of the unique yeasts specific to Orval (Saccharomyces and Brettanomyces). These play an essential role in ensuring the distinctive character and consistent quality of Orval’s products.

TASTING 

Orval beer will delight many consumers, provided that a few simple rules are followed.

Like wine, beer is a delicate beverage. It should be stored away from light at a temperature between 10°C and 15°C. Ideally, it should be served at the same temperature in its original glass, taking care to taste the sediment separately.

Depending on the age of the beer in the bottle, the tasting experience will vary. Young beer is characterized by a bouquet of fresh hops, with fruity notes and a pronounced bitterness. It has a slight haze and a less stable head than a beer aged for six months.

A six-month-old beer displays a bouquet combining yeast aromas with matured hop notes. The bitterness becomes more subdued, while the flavour evolves towards a slight acidity accompanied by hints of yeast and caramel. When served without the sediment, a beer aged six months or more appears particularly bright and clear. This brilliance is reduced when the serving temperature falls below 7°C to 8°C.

The label provides consumers with both the bottling date and the recommended best-consumption date. This makes it easy for anyone to determine the age of an Orval beer and decide whether to enjoy it young or after several months, or even years, of cellar ageing.