Effects of high hydrostatic pressure on shelf life of lager beer

Alpas, Hami
Filtered bright lager beer samples were either treated with high hydrostatic pressure (HHP, 350 MPa for 3 and 5 min at 20 C) or conventional heat pasteurization (60 C for 15 min). A storage period of 56 days showed that HHP and heat pasteurization had similar results in terms of pH and color (p<0.05). However HHP-treated samples had lower bitterness and protein sensitivity and higher chill haze values than the heat pasteurized samples at the end of the storage period. The microbiological stability of HHP-treated beers was the same as that of heat-treated beers, and the development of both lactic and acetic acid bacteria was inhibited for 56 days of storage. Although more studies should be carried out to investigate the effects of HHP treatment on different types of lagers and ales, our results revealed that HHP could be successfully used to increase the shelf life of beer even at temperatures well below those required for heat pasteurization.


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Soysal, C; Soylemez, Z; Bozoglu, F (Springer Science and Business Media LLC, 2004-01-01)
The combined effects of pressure and temperature on the activity of carrot peroxidase (POD) were investigated in the pressure range 0.1-600 MPa and the temperature range 25-45degreesC. At lower pressures (<396 MPa), carrot POD stability increased compared to unpressurized samples. Inactivation of 91% was obtained at 600 MPa and 45degreesC. High hydrostatic pressure (HHP) combined with temperature treatment enhanced the inactivation of carrot POD. Regeneration of POD activity with the combined HHP and temper...
Response surfaces of hazelnut oil yield in supercritical carbon dioxide
Ozkal, SG; Yener, Meryem Esra; Salgin, U; Mehmetoglu, U (Springer Science and Business Media LLC, 2005-01-01)
Response Surface Methodology was used to determine the effects of solvent flow rate (1, 3 and 5 g/ min), pressure (300, 375 and 450 bar) and temperature (40, 50 and 60 degreesC) on hazelnut oil yield in supercritical carbon dioxide (SC-CO2). Oil yield was represented by a second order response surface equation (R-2 = 0.997) using Box-Bhenken design of experiments. Oil yield increased with increasing SC-CO2 flow rate, pressure and temperature. The maximum oil yield was predicted from the response surface equ...
Effect of high pressure (HP) on the quality and shelf life of red mullet (Mullus surmelutus)
Erkan, Nuray; Uretener, Gonca; Alpas, Hami (Elsevier BV, 2010-04-01)
The effect of different temperature/time/pressure high hydrostatic pressure (HP) treatment on the quality and shelf life of red mullet were studied Different high pressure treatments (at 3, 7, 15 and 25 degrees C, 5 to 10 min and 220, 250 and 330 MPa) were tested to establish the best processing conditions for the quality of red mullet The effect of the process on the quality of the sample was examined by colour. Trimethylamine nitrogen (TMA-N) and Thiobarbituric acid number (TBA) analysis. Based on the res...
Effects of high hydrostatic pressure (HHP) on quality parameters and shelf-life of lager beer
Buzrul, Sencer; Alpas, Hami; Bozoğlu, Faruk; Department of Food Engineering (2003)
Filtered bright and unfiltered hazy lager beer samples were either treated with high hydrostatic pressure (200, 250, 300, 350 MPa for 3, 5 and 10 min at 10°C and 20°C) or conventional heat pasteurization (60°C for 15 min). Treatments did not affect ethanol, extract, fermentation degree, density and pH in comparison with untreated beers. Both treatments produced microbiologically stable products. Bitterness, color, protein sensitivity and chill haze parameters were affected by both the HHP and heat treatment...
Modeling high pressure inactivation of Escherichia coli and Listeria innocua in whole milk
Buzrul, Sencer; Alpas, Hami; Largeteau, Alain; DEMAZEAU, Gerard (Springer Science and Business Media LLC, 2008-06-01)
The survival curves of Escherichia coli and Listeria innocua inactivated by high hydrostatic pressure (HHP) were obtained at room temperature (similar to 22 degrees C) and at five pressure levels (400, 450, 500, 550 and 600 MPa) in whole milk. These curves were described by the Weibull model and parameters of this model were reduced from two to one with slight loss of goodness-of-fit. The logarithm of the time constant parameter (delta) of the reduced Weibull model was described with respect to high pressur...
Citation Formats
S. BUZRUL, H. Alpas, and F. BOZOGLU, “Effects of high hydrostatic pressure on shelf life of lager beer,” EUROPEAN FOOD RESEARCH AND TECHNOLOGY, pp. 615–618, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43002.