Quality management - As in practically all sections of a plant, it is all about quality, costs including productivity, work safety (explosion protection), the environment (noise, dust emissions) and hygiene.

The operations covered here go from arrival of the malt truck, hopefully with a quality identical to what one has contracted for, to the grist case. Increasingly a neglected part with sometimes nasty consequences which we will address here. Beer types produced requiring small quantities of special malts, possible blending capabilities and safety considerations play a large role. On the other hand, there are malt storage costs which relate mainly to investment and interest payments for goods in stock. Expensive investment and double testing can be avoi-
ded. 1).e. 2).. ...

Flavour Stability - In order to impartially analyse the flavour stability of beer and the verification of technological improvement measurements cost efficient quick detection methods like the absorption integral and the aniline index have been developed. The intention of this work was to further simplify these quick detection methods, so that they become applicable in laboratory routine.

The flavour stability of beer is an essential quality characteristic. For prognosis and analytical evaluation of flavour stability already various analysis methods are established. However, they involve quite a high instrumental effort in the laboratory to conduct this special analysis (1, 2). A rotary evaporator and a UV/VIS photometer are required.0. .. ...

Malt Quality - A large number of commercial malts were analysed for regermination ability, LOX activity and hydroxylated fatty acid content in congress wort. No correlation exists between these parameters. No conclusions can be drawn from the degree of germination ability of a malt about the activity of enzymes in the embryo. The level of hydroxylated fatty acids in the mash is independent of lipoxygenase activity still present in cured malt.

Beer is subject to permanent changes in taste. During storage, particularly at elevated temperatures, a staling taste develops which is caused primarily by oxidation of unsaturated fatty acids. Flavour impressions arising in aged beer are manifold. (E)-2-nonenal in particular is seen as being the cause of cardboard flavour.

Hallertauer hop crop - Summarised here are key facts about the 2003 Hallertau crop, including suggestions on how to overcome bottlenecks. Due to climate changes, we will probably be faced with weather conditions similar to 2003 from time to time and market partners will have to formulate strategies that will contribute to avoiding supply shortages.

During the main vegetation period for hops, from May to August 2003 the weather in Europe was characterised by low rainfall and high temperatures. Heat and drought had an enormous impact on the Hallertau hop crop, as might have been foreseeable based on the situation in 1994 (1).

Climate in summer 2003

In spring 2003, the soil was sufficiently humid, therefore the hop growing season started well.1° C respectively 2. .

Bitter acids do not remain stable in beer. They break down, depending on time, temperature and incident light. Enquiries from breweries provided grounds for investigating the decrease in 25 commercial beers once again. Within a month of filling, the beers were subjected to ageing for eight months at 22 °C while protected from light. The only differentiation related to hopping according to the indication on the label. These beers were hopped either with pellets, extract or both products.

Together with bitterness units in accordance with Analytica-EBC 9.8, the a-acids and iso-a-acids were measured using HPLC (EBC-Proceedings Maastricht 1997, page 223-231).
Table 1 gives the absolute measured values.2% relative for iso-a-acids and 13.8% relative for bitterness units.
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Beer quality is defined by flavour and taste, colour, foam stability, head retention, lacking turbidity and stability as well as consistency of these properties over a longer period of time. Determination of foam, colour and turbidity is carried out through various objective chemical-technical or biological methods. The flavour and taste of beer, however, cannot, even with great effort, be determined adequately by chemical-physical measurement methods. Only humans can evaluate these parameters after appropriate training and experience. This article describes the requirements for tasters and typical off-flavours and flavour profiles.

Beer is nourishment and a stimulant consisting of several hundreds of single components..

The outline of a method for determination of free chlorine and total chlorine is set out in DIN 38408, Part 4. The DPD method is described here, this is measured with a photometer or a colorimeter in the form of a colour reaction (reference method). Determination of chlorine dioxide is based also on DPD colour comparison.

Disinfectants such as chlorine and chlorine dioxide are used e.g. in the bottle washer, rinser, CIP plant as well as for treating brewing liquor and process water. In as far as the Drinking Water Regulation applies, it requires that the amount of product used be checked weekly and concentration of active substance in the treated water be measured daily. Stipulations also apply to the allowable amounts which can be added. For chlorine, this is 1.1 - 0.05 - 0. ..

The CO2 content is a decisive factor in the taste of the beer. The Landskron Brewery in Görlitz, Germany, now measures CO2 in-line and by doing so, it is modernising the company in a far-sighted way. The unit can also be integrated into new electronic systems without any conversions or upgrades.

This most easterly German brewery has been brewing beer for 135 years behind the now listed brick walls. Today, the Görlitz brewers produce approximately 200,000 hectolitres per year according to a traditional procedure.
The dissolved CO2 influences the taste of the beer as well as other important quality measurements, such as original gravity. In the past, this value was measured manually in an intricate and time-consuming way in front of the pressure tank. Thiedig + Co. ...

In 1988 "gushing" occurred in an extreme manner without an effective counter measure to exist. Where to look for the cause of gushing, where to look for a solution? To meet the challenge the "Wissenschaftsförderung", or Wifö (Promotion of Science by the German brewing industry) started a number of research projects. Over time new aspects arose. Therefore to this day, research is done on the complex issue of "gushing".

Before the "gushing year" of 1988, research had been done on the issue of gushing. However, the results were inconsistent. Thus, early on it was suggested that moulds and gushing are associated. Initial research papers (R 205, 1984) lead to the conclusion that there had to be other presently unknown influencing factors besides moulds.g.g. hydrophobines). ...

Beer stabilisation with silica gel is still a modern process which conserves beer components and taste agents. Silica sols and silica gels can indeed be differentiated in terms of quality and "the cheaper the better" is a miscalculation, as is oftentimes the case.

It can be seen repeatedly that many discoveries and developments proceed simultaneously though independently of each other, because economic imperatives or new scientific findings stimulate a diversity of interests. Thus, at the end of the 1950s, a lot of attention was given to improving beer stability and to the chemistry of polyphenols and haze forming proteins in beer.
Silica gel adsorption of haze-forming protein in beer took off in 1961. Karl Raible and introduced in brewing technology. ...

Much has been studied to understand the staling mechanism of beer and many measures have been taken so far in order to overcome the sensitivity of beer toward staling (1 - 5). However, there are limitations in achieving a significant improvement of flavor stability by these measures alone, as long as the deterioration precursors are carried over from malt into brewhouse. To break through this limitation, the authors set about developing a new innovative strategy to achieve a significant improvement to the beer flavor stability.

Improvement of beer flavor stability has been one of the key issues in brewing technology in recent years.
Most stale flavor compounds derive ultimately from malt. 1: "New innovative strategy"). ...