The following abstracts are just a few examples of some recent records added to the Food Science and Technology Abstracts (FSTA) database, produced by International Food Information Service (IFIS).

Process for manufacture of an alcohol free beer
Swiderek, E.
German Federal Republic Patent Application DE 198 57 625 A1 (2000) [DE 19857625 (19981214) [Swiderek, 32120 Hiddenhausen, Germany De]
An improved process for manufacture of an alcohol free beer is based on addition of yeasts and/or chemical flavourings.


The biological impact of flash pasteurization over a wide temperature interval
Zufall, C.; Wackerbauer, K.
Journal of the Institute of Brewing 106 (3) 163-168 (2000) [2 ref. En] [Fachgebiet Brauwesen, Tech. Univ. Berlin, D-13353 Berlin, Germany]
Investigations were conducted to assess effects of temp. regime (50, 60, 72, 84 or 90°C) and pasteurization unit (PU) value (0, 15, 80 or 500 PU) on microbial inactivation in flash pasteurization of beer. Residence times at each temp. were calculated using the formula of Del Vecchio et al. [ASBC Proceedings (1951) 45-50]. Trials were conducted with a German hazy wheat beer spiked with Lactobacillus brevis, Pediococcus damnosus, Saccharomyces cerevisiae var. carlsbergensis strain Rh, and a wild strain of S. diastaticus. D- and Z-values were calculated for the 4 microorganisms under the pasteurization regimes studied. Saccharomyces spp. were easier to eliminate by pasteurization than the 2 bacterial species. The Del Vecchio PU calculation reflects actual killing performance in the temp. range 60-72°C, and gives a safety margin for yeast inactivation. The Z-values for L. brevis are >6.94 at temp. >72°C, indicating that the real inactivation effect is slightly lower than indicated by calculated PU values. Flash pasteurization at low PU values at temp.> 72°C may be insufficent if high bacterial counts are present, as the real microbial inactivation value is less than indicated by calculated PU values. Under normal conditions with microbial counts <106 l="" beer,="" there="" is="" no="" need="" to="" increase="" the="" pu="" value="" when="" changing="" to="" higher="" pasteurization="" temp.="" with="" shorter="" holding="">


The natural citric acid content of beer
Gerstenberg, H.
Brauwelt 140 (20) 856-857 (2000) [6 ref. De] [Landesuntersuchungsamt fuer das Gesundheitswesen Suedbayern, Augsburg, Germany]
Under the new German Additives Regulations, citric acid may be used as an acidulant in beer. However, beer to which citric acid has been added may not be labelled as having been brewed in accordance with the traditional German beer purity laws. To detect added citric acid in beer, it is necessary to know the naturally occurring citric acid concn. in beer. 340 samples of beer brewed in accordance with the beer purity laws were analysed for citric acid. Citric acid concn. ranged from 93 to 328 mg/l, and increased with increasing original gravity of the beer. When results were presented on a 12% original gravity basis, citric acid concn. ranged from 140 to 232 mg/l (mean 187 mg/l). It is concluded that a citric acid concn. >250 mg/l suggests that citric acid has been added. A citric acid concn. <124 mg/l="" indicates="" either="" infection="" of="" the="" beer="" with="" citrate-decomposing="" lactic="" acid="" bacteria="" or="" use="" of="" unmalted="" adjuncts="" in="" brewing="" the="">


Determination of repeatability and reproducibility of EBC accepted methods. V. Beer
Benard, M. (European Brewery Convention Analysis Committee)
Journal of the Institute of Brewing 106 (3) 135-138 (2000) [3 ref. En]
Two sets of collaborative trials (1 with 13 laboratories and 6 beer samples, the other with 14 laboratories and 5 beer samples) were conducted in accordance with ISO standard 5725 to determine precision data for analytical methods for beer published in Analytica-EBC. Methods studied (with Analytica-EBC numbers in parentheses) covered: alcohol (9.2.1); real, apparent and original extracts (9.4); real degree of fermentation (9.5); colour (9.6); final attenuation (9.7); bitterness (9.8); total N (9.9.1); free amino N (9.10); total polyphenols (9.11); vicinal diketones (9.24.1); total carbohydrates (9.26) and fermentable carbohydrates (9.27). Repeatability and reproducbility values for these analytical techniques are described. These results are to be published in Analytica-EBC under the corresponding methods.

Beer increases plasma antioxidant capacity in humans
Ghiselli, A.; Natella, F.; Guidi, A.; Montanari, L.; Fantozzi, P.; Scaccini, C.
Journal of Nutritional Biochemistry 11 (2) 76-80 (2000) [21 ref. En] [Istituto Nazionale della Nutr., Via Ardeatina 543, 00178 Rome, Italy]
In order to study the contribution of phenols in beer to the reduced risk of cardiovascular disease associated with moderate intake of alcoholic beverages, effects of beer, dealcoholized beer and ethanol (4.5% (v/v)) consumption on plasma antioxidant status were investigated. 14 healthy adults consumed 500 ml of lager, dealcoholized lager or an aqueous ethanol solution and plasma was collected at 1 and 2 h post intake; samples were analysed for total plasma antioxidant activity, plasma antioxidant concn. (vitamin E and glutathione), metabolic indicators (glycaemia, triglyceride and uric acid concn.) and HPLC profiles of certain beer phenols (caffeic, sinapic, syringic and vanillic acids). A significant increase in total plasma antioxidant activity was observed 1 h following beer consumption (P < 0.05)="" which="" returned="" to="" baseline="" values="" by="" 2="" h.="" all="" plasma="" phenols="" tended="" to="" increase="" following="" beer="" consumption;="" significant="" increases="" in="" syringic="" and="" sinapic="" acids="" were="" detected="" (p="">< 0.05).="" metabolic="" indicators="" and="" plasma="" antioxidant="" concn.="" were="" unaffected="" by="" beer="" intervention.="" no="" changes="" in="" plasma="" concn.="" of="" phenols="" or="" plasma="" antioxidant="" activity="" were="" observed="" following="" dealcoholized="" beer="" intake="" which="" is="" attributed="" to="" impaired="" absorption="" of="" phenols="" from="" the="" dealcoholized="" beer.="" consumption="" of="" aqueous="" ethanol="" solution="" had="" no="" influence="" on="" any="" parameters="" examined.="" it="" is="" concluded="" that="" consumption="" of="" beer="" increases="" plasma="" antioxidant="" capacity="" without="" appreciable="" changes="" in="" markers="" of="" metabolic="">


Influence of yeast immobilization on fermentation and aldehyde reduction during the production of alcohol-free beer
Iersel, M. F. M. van; Brouwer-Post, E.; Rombouts, F. M.; Abee, T.
Enzyme and Microbial Technology 26 (8) 602-607 (2000) [20 ref. En] [Bavaria NV, PO Box 1, 5737 Lieshout, Netherlands. Tel. +31 499 428 111. Fax +31 499 428 269. E-mail Martijn.van.Iersel@Bavaria.nl]
Production of alcohol free beer in a packed-bed bioreactor containing a DEAE-cellulose immobilized yeast (Saccharomyces cerevisiae var. uvarum W34) was investigated. It was hoped that the alterations in cell metabolism usually accompanying immobilization could be used to reduce aldehyde-related off-flavour production under low temp., limited fermentation conditions. Temp. and flow rate of the packed bed bioreactor, which was operated continuously, were 0-2°C and 2 m3/h. Sugar consumption, metabolite (ethanol, glycerol, acetic acid) production, aldehyde levels and enzyme activities were measured for immobilized cells and compared to free cells grown in batch culture. Hexokinase and pyruvate decarboxylase activities were higher in immobilized cells, and these increases were accompanied by increased glucose consumption, increased metabolite production and reduced biomass production. NADP-specific alcohol dehydrogenase (ADH) levels were higher in immobilized cells compared to batch cells, and it is suggested that this may be associated with an increased capacity for reduction of aldehydes during the production of alcohol free beer.


Effect of tyrosine on tyramine formation during beer fermentation
Izquierdo-Pulido, M.; Marine-Font, A.; Vidal-Carou, M. C.
Food Chemistry 70 (3) 329-332 (2000) [20 ref. En] [Dep. de Nutr. i Bromatologia, CeRTA, Fac. de Farmacia, 08020 Barcelona, Spain. Tel. +34-934-03-59-30. Fax +34-934-03-59-31. E-mail izquier@farmacia.far.ub.es]
The possibility of a relationship between tyramine formation in beer during fermentation and its precursor amino acid tyrosine was evaluated, with particular focus on the influence of tyrosine and contamination with Pediococcus spp. The beer studied was a pilsner supplied by a Spanish brewery. 54 industrial beer fermentations were followed, samples being obtained during the 6 or 7 days of fermentation and analysed for tyrosine/tyramine and pediococcal counts. Tyrosine levels of 17.8-165.5 mg/l were found in the final beers; in some fermentations, 20% of tyrosine disappeared from wort, whereas in others, this figure was about 70%. Results (tabulated) indicated that it would be difficult to establish a direct relationship between tyramine and tyrosine levels. From previous studies in the same brewery, it was recognized that Pediococcus spp., largely P. damnosus, were critical in tyramine formation. The correlation between Pediococcus counts and tyramine formation yielded a high value, so particular attention should be placed on control of the presence of lactic acid bacteria (in this case pediococci) during beer fermentation, regardless of initial wort concn. of tyrosine.


Malting and brewing trials of new barley varieties - 1998/99
Muller, R.; Booer, C. D.; Baxter, E. D.
HGCA Project Report No. 191, 28pp. (1999) [En] [Brewing Res. Int., Lyttel Hall, Nutfield RH1 4HY, UK]
Suitability of new barley var. (winter var. Pearl and spring var. Century and Decanter) for malting and brewing was assessed. Each var. was compared with a control grown at the same site; Pearl was compared with var. Halcyon, and Century and Decanter were compared with var. Chariot. Barley was malted on a pilot scale to produce a malt with similar characteristics to an ale malt. Each malt was then brewed to produce a standard pale ale. Barley, malts, worts and beers were assessed using Institute of Brewing (IOB) standard methods. Barley endosperm quality was also evaluated using a light transflectance meter. Pearl barley showed lower N content, larger corn size, mealier endosperm and better malting performance than Halcyon. Brewing performance was also better than Halcyon, although final attenuation was poorer and ethanol yield was lower. Pearl beer showed no off flavours, although some taste and aroma differences between Pearl and Halcyon were noted. Quality of Century and Decanter barley was similar to that of Chariot. Century showed similar malting and brewing characteristics to Chariot, although fermentation of Century was faster. Decanter malts had greater protein modification and higher amylolytic activity (DP and DU values) than Chariot and produced beers with higher protein levels and colour. Brewing performance was otherwise similar to the control. Flavour differences between Decanter and Chariot beers, particularly on the sulphury and estery notes, were seen.