Raw materials

Particle analysis and its potential in describing the physico-chemical characteristics of particles in beer were investigated. It was the aim to figure out the feasibility for its application in brewing and beverage science. To describe existing problems in the beverage industry caused by insufficient physico-chemical stability of the beverages a rule of great generality according to the particle characteristics was also defined as follows: Beverages are liquids, in which colloids, also called particles, exist in disperged (e.g. beer) or emulsified (e.g. milk) form. One main particle characteristic is the surface. This can be seen in many interfacial phenomena, like the surface potential. Mathematically it was shown, that especially for small particles the ratio between surface and volume increases. Surfaces carry electric charges, which terminate or change the physico-chemical characteristics of the particles. By combining (1) the particle charge detection with polyelectrolyte titration for determining the surface charge, the surface potential and charge density of particles with (2) the particle size analysis by dynamic stray light to analyze the particle size and particle size distribution, the particles could be characterized.

Hopsteiner

Mid-year acreage estimates for all major hop growing countries have been published. After the 13.4% acreage increase from 2007 to 2008 there has now been a decrease of at least 11.6% for crop 2010. The largest decreases have occurred in USA and China, and the decrease in the PRC could in fact be larger than published. Overall the decrease takes worldwide hop acreage back to its 2007 level, which at the time did not supply enough alpha to meet demand. In the meantime variables have changed so short-term supply should be adequate. ...

Hopsteiner

Once every two years we publish the results of our world beer analyses. For this study, worldwide brands with a yearly production of at least 1 Million hl were selected. These brands represent approx. 43% of the total beer production in 2009, about 720 Million hl beer respectively.

Hopsteiner

As you know, the shortfall of alpha acid for the brewing industry from crops 2005, 2006 and 2007 resulted in acreage increases for crop 2008.

Raw materials

Primary beer gushing is defined as the wild and uncontrolled overfoaming of packaged beer induced by contaminated raw materials as barley and malt. It is generally admitted that most probably amphipathic molecules such as hydrophobins and non-specific lipid transfer proteins (ns-LTPs) are responsible for this phenomenon. These molecules are synthesized by moulds and by vegetal tissues respectively in order to modify the polarity of surfaces and the solubility of molecules. At present, hydrophobins are extensively studied as they are considered as the major responsible molecules involved in primary gushing. This review compiles the relevant fundamental physical and chemical properties of CO2 and experimental observations at laboratory and pilot scale.0 till 4.0 ATU of CO2 )..

Raw materials

Aged beer flavour was studied by ageing a lager beer in different conditions (varying temperature-time profiles, different oxidative conditions and varying pH and ethanol concentrations). This led to beers with a varying aged flavour, which could be explained by differences in the reaction rate of ageing reactions. High temperatures, oxidative conditions and to a lesser extent, a lower pH, accelerated beer ageing. Enhanced (E)-2-nonenal formation probably led to the greater perception of cardboard flavour after ageing at high temperatures. Madeira flavour was only perceived after ageing at 20 °C and ribes flavour was mainly perceived in oxidatively aged beer..

Hopsteiner

1) After quite a long winter, spring work was started in the hop fields some days ago. Some farmers are still fastening the wires for training the hop vines. Normally, this work will have already been done whilst the ground is frosty in winter in order to avoid surface damage to the soil by heavy machinery.

Raw materials

The Research Center Weihenstephan for Brewing and Food Quality at the Technical University Munich reacts to numerous enquiries from different breweries all over the world concerning:

Hopsteiner

Traditionally used by the British cask ale brewers to add a strong, distinctive hop character to beer in cask, this practice has also now been adopted by the world craft brewing sector to produce a range of significantly different products.

Raw materials

New industrial brewing yeasts*1 have been generated by introduction of two genes involved in valine biosynthetic pathway in order to clarify their roles for the reduction of diacetyl content in beer. The Saccharomyces cerevisiae genes as well as lager*2 genes both BAT1 (encoding branched-chain amino acid aminotransferase) and BAT2 (encoding branched-chain amino acid aminotransaminase) have been transferred into brewer’s yeast. Within this approach it was possible to decrease diacetyl levels at the end of main fermentation without affecting the by-product profile of the beer negatively. Furthermore, our results pointed to the regulation of these genes concerning diacetyl formation.

BrewingScience - Monatsschrift für Brauwissenschaft, 63 (January/February 2010), pp. 6-13

Raw materials

The formation and removal of dimethyl sulfide (DMS) was studied during a new method for wort production, without classic wort boiling. This was compared with classic brewing trials comprising one hour of wort boiling. The new wort production method consists of fine milling of malt under water to minimize LOX reactions, mashing-off at 95 °C, membrane assisted thin bed filtration, in-line injection of clean steam in the filtered wort and stripping of the wort while entering the combination vessel (‘boiling’ kettle/decantor), optional clean steam injection during filling of the combination vessel, and finally decantation of the hot trub in the same combination vessel.5 hours as compared to at least 3.5 hours for classic brewing using the same brewing line..