Adsorption and Desorption of Beer and Coffee on a Lipid Membrane as Related to Sensory Bitterness

Abstract

An objective evaluation method for the bitter characteristics of beverages was developed with a lipid-coated quartz-crystal microbalance connected with a flow injection system. Observation of the adsorption and desorption of beer and coffee on the lipid membrane in the buffer system specifically noted the hydrophobic interactions between the beer and coffee components and the lipid membrane, which could simulate the bitter reception reactions on the tongue. The adsorption or duration of beer or coffee on the lipid membrane in the acetate buffer successfully agreed with the bitter intensity or duration in the sensory evaluation, respectively. Key words:Beer, coffee, lipid membrane sensor, bitterness. -2863(9'8-32Bitterness is one of the most important organoleptic characteristic of several beverages such as beer and coffee, and not only the intensity but also the duration affect the bitter quality in a sensory evaluation. Lewis et al. 15 have emphasized that the time-intensity rating of bitterness provides a category scaling and additional information, including the rates of increase and decrease of bitterness, persistence of maximum intensity, changes caused by swallowing, and duration of after-taste. Hughes et al. [9][10][11] have studied the sensory characteristics of isohumulones using the time-intensity method. However, sensory analysis, as traditionally applied, suffers from an objective, unbiased, and reproducible evaluation, thus necessitating statistical handling of the data.Previously, we used a lipid-coated quartz-crystal microbalance (QCM) 12 to relate adsorption of beer/beer components on the lipid membrane with sensory perception of bitterness for the same beer/beer components. The adsorption of beers on the lipid membrane in the acetate buffer system showed a significant correlation with their bitter intensity and duration as judged by a sensory evaluation. However, there is a potential problem in that the correlation between the adsorption value and bitter intensity in the sensory evaluation might mathematically also lead to a correlation between the adsorption value and bitter duration, because the relationship between bitter intensity and duration show good correlation.The aim of this study was to improve the lipid membrane sensor for reasonable determination of not only bitter intensity but also bitter duration of beverages using a lipid-coated QCM connected with a flow injection system, imaging the behavior of bitter components on the tongue while drinking beverages, and to study the bitter characteristics of beer and coffee. 1%8)6%07 %2( 1)8,3( &IIVW ERH GSJJIIWJapanese all-malt beer and European stout beer were commercially purchased. The isohumulone contents by HPLC analyses were 24 mg/L and 41 mg/L, respectively. Beer lacking isohumulones was brewed in our 400 L pilot plant. Wort was produced with malt and adjuncts but without hop addition by a decoction method, fermented at 8°C for about 10 days, and then at 0°C for about 1.5 months.Canned coffees were provided from Production Deve...

Classification of non-alcoholic beer based on aftertaste sensory evaluation by chemometric tools

“…A similar approach is the adsorption and desorption of beer and coffee on a lipid membrane simulating the bitter reception of the tongue. The measurement of bitter intensities and durations showed good correlation to sensory experiments (Kaneda & Takashio, 2005;Kaneda, Watari, Takshio, & Okahata, 2003).…”

A survey of the 2001 to 2005 quartz crystal microbalance biosensor literature: applications of acoustic physics to the analysis of biomolecular interactions

“…The manifold number of analyte-membrane/receptor combinations possible with a label-free piezoelectric sensor is apparent from diverse types of measurements reported for a range of analytes. Selected examples include interactions of membranes with tannins (Kaneda et al, 2002b(Kaneda et al, , 2003b, divalent non-metallic cations (Ekeroth et al, 2002), metal ions (Bukreeva et al, 2003), metal-binding proteins , lipases (Pastorino and Nicolini, 2002;Snabe and Petersen, 2003;Justesen et al, 2004), lectins (Hildebrand et al, 2002), Shiga toxin (Uzawa et al, 2002), glucose (Galeska et al, 2001;Svobodová et al, 2002), beer (Kaneda et al, 2002a(Kaneda et al, , 2005, coffee (Kaneda et al, 2003a) and detergents (Shimomura et al, 2003).…”

Development of Taste Sensor with Lipid/Polymer Membranes for Detection of Umami Substances Using Surface Modification

“…Taste sensing systems, a category of chemical sensors, have received much attention in recent years due to their objectivity and reproducibility, which offer important economic benefits to food industries [1][2][3][4][5] and pharmaceutical industries [6][7][8]. These systems encompass a range of sensing methodologies [9,10], such as electrochemical methods [11][12][13][14][15][16][17][18][19][20][21] (e.g., potentiometry or voltammetry), biomimetic biosensing [22,23], optical methods [24,25], mass change sensing methods [26] or enzymatic methods [27][28][29].…”