Brewery Process Research Articles

Development of a New Rheological Laboratory Method for Mash Systems—Its Application in the Characterization of Grain Modification Levels

The brewery mashing process is an enzymatic-, time-, and temperature-dependent degradation process of viscosity creating macromolecules such as proteins, arabinoxylans, β-glucan, starch, and dextrins. This paper reports on the development of a new laboratory-based rheological method using a sensitive rotational rheometer that can determine viscosity changes in complex systems such as the brewery mashing process that contain dissolved and suspended materials. A Bohlin CS-50 rheometer, together with a specially designed star-shaped paddle rotor that enables mash particles to stay in suspension throughout measurement, was used. Studies were conducted to simulate an industrial mashing process, taking into account temperature, time, grist loads, adjunct amounts, and enzyme levels. The developed method was used to characterize the effects of different levels of malt modification. Clear correlations were made between the level of grain modification and the output rheological data points of peak viscosity at 50°C (R2 = 0.9769), breakdown rate at 50°C (R2 = 0.9784), peak viscosity at gel (R2 = 0.9935), peak gel area (R2 = 0.9943), the gelatinized starch breakdown rate at gel peak to 44 min (R2 = 0.9736), and the rate of breakdown at 63°C at start and 63°C at end (R2 = 0.9933). The developed rheological method is a useful tool for characterizing grain quality with regard to macromolecular viscosity compounds and the grains endogenous enzymatic capabilities.

Energy and materials conversion with the help of regeneration and energy transformation

The comprehension of the unity of materials and energy conversion is the basis for energetic effective design of materials conversion processes. Besides regenerative heat utilisation energy transformation can open up further possibilities of energy saving. The principal procedure for the design of energetic effective regenerative heat transfer systems and the effects which are within reach with regeneration are shown through the instance of a brewery — a typical multilevel heat consumer. Brewery process offers possibilities for heat transformation both in open and closed cycles. For the purpose of an equally good description of heat fluxes and material fluxes in open heat transformation processes, a concept for exergetic evaluation of material fluxes is necessary. Normalised exergy and corresponding generalised temperature are developed as evaluation characteristics and illustrated with help of an energy–entropy diagram. Heat transformation in the sense of open cycles appears also in single processes or unit operations. Aspects of energy transformation in connection with materials conversion are discussed through the examples of absorption and dehumidification. The regard of chemical reactions from the view of heat transformation opens interesting aspects for the evaluation of the conversion potential of fuels and other chemical compounds. This is discussed for some thermochemical cycles, reversible combustion and fuel cell.

バイオマスエネルギー資源としての有機性廃棄物とビール製造廃液からのCO<SUB>2</SUB>固定化

[in Japanese]

最近の燃料電池の開発動向

The purpose of this report is to have a general view of the present status on research, development and demonstration of fuel cells in addition to their principle and characteristics. Among a few kinds of fuel cells, PAFC has almost reached at the semi-commercial stage, and large efforts have now been given for realizing the PAFC as cogeneration plant using the biogas from garbage and beer brewery process. MCFC is on the way of the demonstration stage with a large scale system under the ledership of NEDO and MITI in Japan. With respect to SOFC several organizations have been taking part in its research and development projects for the purpose of developing super-high efficient power system. PEFC is becoming more and more attractive in expectation of being especially realized as fuel cell propulsion system for electric vehicles and also as residential co-generation devices. A large number of companies have recently entered into the fields related to PEFC system development including fuel delivery infrastructure.

The Contribution of 4-Hydroxyfuranone Derivatives to the Aroma of Commercial Beers and Malts

Analysis of hot water extracts from a range of commercial malts showed that 2,5-dimethyl-4-hydroxy-3(2H)furanone (DMHF) varied from undetectable (lager malt) to 4.2 mg/litre (crystal malt), a concentration twenty-six times the flavour threshold in water. 5-Methyl-4-hydroxy-3 (2H)furanone (MHF) was detected in all samples except one but was always well under its flavour threshold value. 2(or 5)-Ethyl-5(or 2)-methyl-4-hydroxy-3(2H)furanone (EMHF) was not detected in any of the samples. Fermentation of lager, ale and crystal malt extracts with an ale strain of yeast led to the appearance of EMHF in all cases as well as additional DMHF. The greatest increases in both compounds was with the ale malt. Both increases and decreases occurred in MHF concentration as a result of fermentation but final levels were always well below the flavour threshold value. Analysis of ten commercial beers found DMHF in all the samples and in five cases levels exceeded twice the flavour threshold value in beer with flavour units from 2.4 to 9.1. A flavour panel noted that in four of these cases the beer had a distinctly sweet/caramel aroma which is typical of DMHF. EMHF was undetectable in six samples, detectable, but unquantifiable, in three cases but at about 80% of the flavour threshold value in the remaining sample. MHF was found in all samples but at insignificant levels. The results show that DMHF is an important flavour compound in British ales and EMHF may make a contribution in a limited number of situations. The contribution of malt type, brewery processing and yeast strain in determining the concentration of the two 4-hydroxyfuranones in beer remains uncertain.

A New Brewery By-Product for Turkey Diets ,

The objective of this study was to determine energy, methionine, lysine, and protein availability of solids concentrated from brewery process effluent through the Carver-Greenfield process. Analysis of these concentrated solids revealed 30% protein and 23% fat content. A biological evaluation was implemented to determine the availability of energy and protein to poults and to determine possible existence of unidentified growth factors. Sixteen diets were fed to 560 male poults. Five replicate groups of 7 birds each were housed in electrically heated Jamesway batteries.The study utilized Large White male turkeys, fed 0 to 20% levels of the test product (labeled CVS) covering a period from 1 day to 4 weeks of age. The energy value of CVS for poults appeared similar to the TME score of 3.02 kcal/g. Protein utilization was best when CVS was fed at 5% of the diet, and was equal to that of dehulled soybean meal. Five percent CVS substituted for one unidentified growth factor (UGF) source and appeared to have an additive effect with another UGF source. On two treatments, bird body weights averaged nearly 1000 g each at 4 weeks.It was concluded that CVS at up to 10% of the diet performed adequately as a product to provide usable protein and energy for early poult growth.