Some of the temp requirements will depend on teh beans and what your wanting to achieve...Originally Posted by 04352E3437182E2A262022470 link=1257932633/0#0 date=1257932633
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The final quality of espresso coffee (EC) depends upon certain technical conditions, such as the extraction temperature used in preparing it. The aim of this work was to investigate the effects of water temperature (88, 92, 96 and 98°C) on the final quality of three types of EC (Arabica, Robusta Natural blend and Robusta Torrefacto blend) in order to select the optimal temperature. Volatile compound (analysed by Static headspace gas chromatography/mass spectrometry) and sensory flavour profiles were the most relevant parameters, whereas physicochemical, taste and mouthfeel parameters were not very useful for selecting the water temperature.
For Arabica and Robusta Natural blend ECs, 92°C was the optimal water temperature. For Robusta Torrefacto blend EC the overall acceptability might lead to the selection of 88°C as the ideal water temperature, but the high percentages of key odorants related to roasty and earthylmusty flavours and the not hot enough perception dictated the selection of 92 °C in this case as well.
Then to add to the confusion / clarity..
Espresso coffee is a polyphasic beverage in which the physico-chemical and sensory characteristics obviously depend on both the selection of ground roasted coffee and the technical conditions of the percolation process.
The aim of this work was to evaluate the influence of the coffee/water ratio on the physico-chemical and sensory quality of espresso coffee. Furthermore, the influence of botanical varieties (Arabica and Robusta) and the type of roast (conventional and torrefacto) on the selection of coffee/water ratio was studied. The relationship between pH and the perception of acidity intensity is discussed in relation to the influence of the coffee/water ratio, type of coffee and roast. The optimisation of other technical parameters in previous studies seemed to minimise the influence of an increase in the coffee/water ratio on the extraction of soluble and solid compounds.
In fact, only some sensory attributes, such as bitterness, astringency and burnt, acrid and earthy/musty flavours were proposed as relevant to the selection of 6.5 g 40 mL[ch8722]1 or 7.5 g 40 mL[ch8722]1 in conventional roasted coffees (Arabica 100% and Robusta blend), and 6.5 g 40 mL[ch8722]1 in torrefacto roasted coffees. On the other hand, the addition of sugar during the roasting process in torrefacto roast coffees seemed to contribute to a higher generation of acids, melanoidins and other compounds by the Maillard reaction or caramelisation, which led us to select the lowest coffee/water ratio. Copyright © 2006 Society of Chemical Industry