abstractEspressocoffee extraction i

abstract
Espressocoffee extraction is the most common brewing method in Italy and it is becoming very popular in many other countries around the world. Water (including its ionic content) is an essential ingredient and its role inEspressobrewing must be taken into due consideration. It is well known that water treatment is necessary to remove possible off-flavours deriving from the disinfection performed at municipal waterworks as well as to prevent expensive professionalEspressocoffee machine from scaling problems. However, there is little awareness of the direct effect of water composition on the quality of coffee beverages, particularly forEspressocoffee. In this paper, the state of the art is reviewed with emphasis of water/coffee components interaction during the brewing process. The role played by alkalinity and selected cations on sensory properties of Espressocoffee is discussed.

1. Introduction
Water is the second essential ingredient for coffee brewing, and, from a quantitative point of view, it is the most important. Several early studies have been focussed at individuating possible correlation between water (and its ionic content) and coffee beverage quality (Gardner, 1958; Lockhart, Tucker, & Merritt, 1955; Pangborn, 1982; Pangborn, Trabue, & Little, 1971; Tassan & Russell, 1974). These studies have been carried out by using filter or drip coffee extraction as coffee beverage sample preparation method. In the typical set-up, a paper filter is placed in a proper coneshaped holder. Medium ground coffee is put into the filter and the holder placed on top of a glass jug. Boiled water is poured into
the filter and allowed to seep through. The resulting coffee beverage is a clean, transparent system (Petracco, 2001). In a wide range of natural mineralised drinking waters, differences in the visual
attributes of brewed coffee often were greater than differences in flavour (Pangborn, 1982). However, electrolytes in both natural drinking waters and in model water systems adversely influenced
the quality of the resultant beverages (Pangborn et al., 1971). In particular the carbonates were the worst offenders, resulting in a bitter, flat coffee. Moreover, although a certain degree of acidity
is characteristic of brewed coffee, the sourness of coffee prepared from distilled water has been found to be excessive (Pangborn et al., 1971). The relevance of water alkalinity in influencing (neutralising) coffee acidity has been evidenced by Sivetz (1972).In particular, ‘‘for each 100 ppm of water alkalinity, the pH is raised about 0.22 unit for roast and ground coffees and about 0.33 unit for instant coffees” (Sivetz, 1972). It has been also found that the concentration and species of ions in solution change the rate at which water passes through the bed of ground coffee, thereby causing differential extraction of coffee solids (Gardner, 1958). Carbonates and bicarbonates with excessive sodium ions have been found to affect the brewing time, both having a retarding effect in direct relation to their concentration, while all other ions normally present in municipal water supplies appeared to have little effect, if any on brewing time (Gardner, 1958). For this reason, Gardner (1958)suggested to avoid the use of ion exchange (replacement of calcium and magnesium with sodium) to treat water containing a high concentration of bicarbonate. More recently, water quality affecting the taste of filter or drip
coffee beverage has been discussed in terms of the presence of foreign flavours due to disinfecting treatments (chlorination) and of water hardness, being the latter investigated in detail (Cammenga
& Zielasko, 1997). In fact, if, on one hand, possible foreign flavours directly affect the coffee taste, on the other hand, water hardness through its scaling potential, indirectly affect the beverage quality
by reducing heat transfer effectiveness of heat exchangers and then affecting the extraction temperature. In spite of the increasing popularity of the Espresso coffee extraction as a coffee preparation method around the world, little is known about the role played by water and its ionic content in beverage quality and acceptability.Espresso– the word refers to a preparation made on request expressly for the occasion – is brewed by rapidly percolating a small quantity of pressurised,
heated water through a compressed cake of finely ground roasted coffee. The process is applied (brewing time) until the beverage volume in the cup meets the personal preferences of the consumer
and/or the regional traditions, in Italy, for instance, this falls in the range 15–50 ml, with an optimal outcome at 25–30 ml (regular Espressowith a brewing time of 25–30 s). The resulting beverage,
differently from drip coffee, must be topped by a velvety thick, reddish-brown foam calledcremato be considered properly prepared and to be appreciated by connoisseurs. This peculiar brewing method requires specialised and costly equipment that can heat water to a temperature of 92–94 C and then pressurise it to 9 ± 2 bar (Illy, 2002). The detrimental effect of foreign flavours as well as of water
hardness in Espresso brewing is well documented (Petracco, 2001; Schulman, 2002). However, as far as we know, only two papers reported quantitative data on the effects of water composition
and water treatment onEspressocoffee brewing (Fond, 1995; Rivetti et al., 2001). Moreover, the role played by water composition on thecremaproperties has not yet been the subject of study. As
matter of fact, the few reports onEspressocoffee foam mainly focused on its chemical aspects and interfacial properties neglecting the effect of water ingredient (D’Agostina et al., 2004; Ferrari,
Navarini, Liggieri, Ravera, & Suggi Liverani, 2007; Navarini, Ferrari, Suggi Liverani, Liggieri, & Ravera, 2004; Nunes, Coimbra, Duarte, & Delgadillo, 1997). In this paper, the state of the art is reviewed with emphasis of water/coffee components interaction during the brewing process. Alkaline scale formation and sodium softening chemistry is briefly discussed in view of its relevance inEspressocoffee quality. Moreover, new experimental data on the effect of water composition on Espressocoffee foam is also reported and discussed.

Hasil (Bahasa Indonesia) 1:

abstrakEkstraksi Espressocoffee adalah metode pembuatan bir yang paling umum di Italia dan itu menjadi sangat populer di banyak negara lain di seluruh dunia. Air (termasuk isinya ionik) adalah unsur penting dan inEspressobrewing peran yang harus diambil karena pertimbangan. Hal ini juga diketahui bahwa pengolahan air diperlukan untuk menghapus kemungkinan off-rasa berasal dari desinfeksi dilakukan di municipal pengairan serta untuk mencegah mesin mahal professionalEspressocoffee skala masalah. Namun, ada sedikit kesadaran akan efek langsung dari komposisi air pada kualitas kopi minuman, terutama forEspressocoffee. Dalam tulisan ini, canggih ini ditinjau dengan penekanan interaksi komponen air kopi selama proses pembuatan bir. Peran yang dimainkan oleh alkalinitas dan dipilih kation pada sifat sensorik Espressocoffee dibahas.1. PendahuluanAir adalah unsur penting kedua untuk menyeduh kopi, dan, dari sudut pandang kuantitatif, adalah yang paling penting. Beberapa studi awal telah difokuskan pada individuating mungkin korelasi antara air (dan isinya ionik) dan minuman kopi berkualitas (Gardner, 1958; Lockhart, Tucker, & Merritt, 1955; Pangborn, 1982; Pangborn, Trabue, & sedikit, 1971; Tassan & Russell, 1974). Studi ini telah dilakukan dengan menggunakan filter atau kopi drip ekstraksi sebagai metode persiapan sampel minuman kopi. Dalam set-up khas, kertas filter ditempatkan di dudukan tepat coneshaped. Kopi bubuk yang sedang dimasukkan ke dalam saringan dan pemegang diletakkan di atas kendi kaca. Air direbus dituangkan ke dalamfilter dan diizinkan untuk meresap melalui. Minuman kopi yang dihasilkan adalah bersih, transparan sistem (Petracco, 2001). Dalam berbagai alam mineralisasi minum air, perbedaan dalam visualatribut diseduh kopi sering yang lebih besar dari perbedaan dalam rasa (Pangborn, 1982). Namun, elektrolit dalam kedua air minum yang alami dan model sistem air negatif dipengaruhikualitas minuman resultan (Pangborn et al., 1971). Khususnya karbonat adalah pelanggar terburuk, mengakibatkan kopi pahit, datar. Selain itu, meskipun tingkat keasaman tertentuis characteristic of brewed coffee, the sourness of coffee prepared from distilled water has been found to be excessive (Pangborn et al., 1971). The relevance of water alkalinity in influencing (neutralising) coffee acidity has been evidenced by Sivetz (1972).In particular, ‘‘for each 100 ppm of water alkalinity, the pH is raised about 0.22 unit for roast and ground coffees and about 0.33 unit for instant coffees” (Sivetz, 1972). It has been also found that the concentration and species of ions in solution change the rate at which water passes through the bed of ground coffee, thereby causing differential extraction of coffee solids (Gardner, 1958). Carbonates and bicarbonates with excessive sodium ions have been found to affect the brewing time, both having a retarding effect in direct relation to their concentration, while all other ions normally present in municipal water supplies appeared to have little effect, if any on brewing time (Gardner, 1958). For this reason, Gardner (1958)suggested to avoid the use of ion exchange (replacement of calcium and magnesium with sodium) to treat water containing a high concentration of bicarbonate. More recently, water quality affecting the taste of filter or dripcoffee beverage has been discussed in terms of the presence of foreign flavours due to disinfecting treatments (chlorination) and of water hardness, being the latter investigated in detail (Cammenga& Zielasko, 1997). In fact, if, on one hand, possible foreign flavours directly affect the coffee taste, on the other hand, water hardness through its scaling potential, indirectly affect the beverage qualityby reducing heat transfer effectiveness of heat exchangers and then affecting the extraction temperature. In spite of the increasing popularity of the Espresso coffee extraction as a coffee preparation method around the world, little is known about the role played by water and its ionic content in beverage quality and acceptability.Espresso– the word refers to a preparation made on request expressly for the occasion – is brewed by rapidly percolating a small quantity of pressurised,heated water through a compressed cake of finely ground roasted coffee. The process is applied (brewing time) until the beverage volume in the cup meets the personal preferences of the consumerand/or the regional traditions, in Italy, for instance, this falls in the range 15–50 ml, with an optimal outcome at 25–30 ml (regular Espressowith a brewing time of 25–30 s). The resulting beverage,differently from drip coffee, must be topped by a velvety thick, reddish-brown foam calledcremato be considered properly prepared and to be appreciated by connoisseurs. This peculiar brewing method requires specialised and costly equipment that can heat water to a temperature of 92–94 C and then pressurise it to 9 ± 2 bar (Illy, 2002). The detrimental effect of foreign flavours as well as of waterhardness in Espresso brewing is well documented (Petracco, 2001; Schulman, 2002). However, as far as we know, only two papers reported quantitative data on the effects of water compositionand water treatment onEspressocoffee brewing (Fond, 1995; Rivetti et al., 2001). Moreover, the role played by water composition on thecremaproperties has not yet been the subject of study. Asmatter of fact, the few reports onEspressocoffee foam mainly focused on its chemical aspects and interfacial properties neglecting the effect of water ingredient (D’Agostina et al., 2004; Ferrari,Navarini, Liggieri, Ravera, & Suggi Liverani, 2007; Navarini, Ferrari, Suggi Liverani, Liggieri, & Ravera, 2004; Nunes, Coimbra, Duarte, & Delgadillo, 1997). In this paper, the state of the art is reviewed with emphasis of water/coffee components interaction during the brewing process. Alkaline scale formation and sodium softening chemistry is briefly discussed in view of its relevance inEspressocoffee quality. Moreover, new experimental data on the effect of water composition on Espressocoffee foam is also reported and discussed.

Hasil (Bahasa Indonesia) 2:

abstrak
ekstraksi Espressocoffee adalah metode pembuatan bir yang paling umum di Italia dan itu menjadi sangat populer di banyak negara lain di seluruh dunia. Air (termasuk konten ionik) merupakan unsur penting dan peran inEspressobrewing yang harus dipertimbangkan karena. Hal ini juga diketahui bahwa pengolahan air diperlukan untuk menghapus kemungkinan off-rasa yang berasal dari desinfeksi dilakukan pada pengairan kota serta untuk mencegah mesin professionalEspressocoffee mahal dari skala masalah. Namun, ada sedikit kesadaran akan efek langsung dari komposisi air pada kualitas minuman kopi, khususnya forEspressocoffee. Dalam tulisan ini, keadaan seni ditinjau dengan penekanan air / interaksi komponen kopi selama proses pembuatan bir. Peran yang dimainkan oleh alkalinitas dan kation yang dipilih pada sifat sensori dari Espressocoffee dibahas. 1. Pendahuluan Air adalah unsur penting kedua untuk menyeduh kopi, dan, dari sudut pandang kuantitatif, itu adalah yang paling penting. Beberapa penelitian awal telah difokuskan pada individuating korelasi mungkin antara air (dan konten ionik) dan kualitas minuman kopi (Gardner, 1958; Lockhart, Tucker, & Merritt, 1955; Pangborn, 1982; Pangborn, Trabue, & kecil, 1971; Tassan & Russell, 1974). Studi-studi ini telah dilakukan dengan menggunakan filter atau kopi ekstraksi tetes sebagai metode minuman kopi persiapan sampel. Dalam khas set-up, filter kertas ditempatkan dalam wadah coneshaped tepat. Kopi darat media dimasukkan ke dalam filter dan pemegang ditempatkan di atas kendi kaca. Air rebusan dituang ke dalam filter dan dibiarkan merembes melalui. Minuman kopi yang dihasilkan adalah bersih, sistem yang transparan (Petracco, 2001). Dalam berbagai perairan minum mineral alami, perbedaan visual atribut kopi diseduh sering lebih besar dari perbedaan dalam rasa (Pangborn, 1982). Namun, elektrolit di kedua perairan minum alami dan sistem air model yang buruk mempengaruhi kualitas minuman yang dihasilkan (Pangborn et al., 1971). Khususnya karbonat adalah pelanggar terburuk, menghasilkan pahit, kopi datar. Selain itu, meskipun tingkat tertentu keasaman adalah karakteristik dari kopi tubruk, yang asam kopi dibuat dari air suling telah ditemukan untuk menjadi berlebihan (Pangborn et al., 1971). Relevansi alkalinitas air dalam mempengaruhi (penetral) keasaman kopi telah dibuktikan oleh Sivetz (1972) .Dalam tertentu, '' untuk setiap 100 ppm alkalinitas air, pH dinaikkan sekitar 0,22 satuan untuk panggang dan tanah kopi dan sekitar 0,33 Unit untuk kopi instan "(Sivetz, 1972). Telah juga menemukan bahwa konsentrasi dan jenis ion dalam larutan mengubah tingkat di mana air melewati tempat tidur kopi bubuk, sehingga menyebabkan ekstraksi diferensial padatan kopi (Gardner, 1958). Karbonat dan bikarbonat dengan ion natrium yang berlebihan telah ditemukan untuk mempengaruhi waktu pembuatan bir, keduanya memiliki efek penghambat dalam hubungan langsung dengan konsentrasi mereka, sementara semua ion lain biasanya hadir dalam pasokan air kota tampaknya memiliki pengaruh yang kecil, jika ada waktu pembuatan bir ( Gardner, 1958). Untuk alasan ini, Gardner (1958) menyarankan untuk menghindari penggunaan pertukaran ion (penggantian kalsium dan magnesium dengan natrium) untuk mengobati air yang mengandung konsentrasi tinggi bikarbonat. Baru-baru ini, kualitas air mempengaruhi rasa filter atau menetes kopi minuman telah dibahas dalam hal kehadiran rasa asing karena desinfektan perawatan (klorinasi) dan kesadahan air, menjadi yang terakhir diselidiki secara rinci (Cammenga & Zielasko, 1997) . Bahkan, jika, di satu sisi, mungkin rasa asing secara langsung mempengaruhi rasa kopi, di sisi lain, kekerasan air melalui potensi skala nya, secara tidak langsung mempengaruhi kualitas minuman dengan mengurangi efektivitas perpindahan panas dari penukar panas dan kemudian mempengaruhi suhu ekstraksi. Terlepas dari meningkatnya popularitas kopi ekstraksi Espresso sebagai metode persiapan kopi di seluruh dunia, sedikit yang diketahui tentang peran yang dimainkan oleh air dan kadar ion dalam kualitas minuman dan acceptability.Espresso- kata mengacu pada persiapan yang dilakukan atas permintaan tegas untuk acara - diseduh dengan cepat meresap sejumlah kecil bertekanan, air dipanaskan melalui kue kompresi ditumbuk halus kopi panggang. Proses ini diterapkan (waktu pembuatan bir) sampai volume minuman dalam cangkir memenuhi preferensi pribadi konsumen dan / atau tradisi daerah, di Italia, misalnya, ini jatuh dalam kisaran 15-50 ml, dengan hasil optimal di 25-30 ml (Espressowith biasa waktu menyeduh 25-30 s). Minuman yang dihasilkan, berbeda dari kopi drip, harus diakhiri dengan beludru tebal, busa coklat kemerahan calledcremato dianggap dipersiapkan dengan baik dan harus dihargai oleh para pecinta. Metode pembuatan bir aneh ini memerlukan peralatan khusus dan mahal yang dapat memanaskan air dengan suhu 92-94 C dan kemudian menekan ke 9 ± 2 bar (Illy, 2002). Efek merugikan dari rasa asing maupun air kekerasan di Espresso pembuatan bir didokumentasikan dengan baik (Petracco, 2001; Schulman, 2002). Namun, sejauh yang kita tahu, hanya dua makalah melaporkan data kuantitatif pada efek dari komposisi air dan pengolahan air onEspressocoffee menyeduh (Fond, 1995; Rivetti et al, 2001.). Selain itu, peran yang dimainkan oleh komposisi air di thecremaproperties belum menjadi subyek penelitian. Sebagai soal fakta, beberapa laporan onEspressocoffee busa terutama terfokus pada aspek kimia dan sifat antarmuka mengabaikan pengaruh bahan air (D'Agostina et al, 2004;. Ferrari, Navarini, Liggieri, Ravera, & Suggi Liverani, 2007; Navarini , Ferrari, Suggi Liverani, Liggieri, & Ravera, 2004; Nunes, Coimbra, Duarte, & Delgadillo, 1997). Dalam tulisan ini, keadaan seni ditinjau dengan penekanan air / interaksi komponen kopi selama proses pembuatan bir. Pembentukan skala Alkaline dan natrium pelunakan kimia dibahas secara singkat dalam pandangan relevansinya kualitas inEspressocoffee. Selain itu, data eksperimen baru tentang pengaruh komposisi air busa Espressocoffee juga dilaporkan dan dibahas.