title: Purification of barley dimeric α-amylase inhibitor-1 (BDAI-1) and avenin-like protein-a (ALP) from beer and their impact on beer foam stability.
abstract: Foam stability is a key factor of beer quality for consumers and brewers. Recent beer proteome analyses have suggested that barley dimeric α-amylase inhibitor-1 (BDAI-1) and avenin-like protein-a (ALP) derived from barley are important for beer foam stability. In this study, BDAI-1 and ALP were purified from a Japanese commercial beer sample using salt precipitation and column chromatography. The purification level was verified using two-dimensional gel electrophoresis, mass spectrometry, and database searches. Purified BDAI-1 and ALP were added to a beer sample to compare the foam stability to that of a control beer sample. As a result, beer foam stability was significantly improved by BDAI-1 but not by ALP, thereby suggesting that BDAI-1 affects beer foam stability whereas ALP does not.
authors.affiliation: Bioresources Research and Development Department, Sapporo Breweries Ltd., 37-1, Nitta Kizaki, Ota, Gumma 370-0393, Japan. Electronic address: takashi.iimure@sapporobeer.co.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Iimure
authors.affiliation: Bioresources Research and Development Department, Sapporo Breweries Ltd., 37-1, Nitta Kizaki, Ota, Gumma 370-0393, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kihara
authors.affiliation: Institute of Plant Science and Resources, Okayama University, 2-20-1, Chuo, Kurashiki, Okayama 710-0046, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Sato
authors.affiliation: Bioresources Research and Development Department, Sapporo Breweries Ltd., 37-1, Nitta Kizaki, Ota, Gumma 370-0393, Japan.
authors.forename: Kensuke
authors.initials: K
authors.lastname: Ogushi
mesh_terms: D001515:Beer / Q000032:analysis*; D015180:Electrophoresis, Gel, Two-Dimensional; D004791:Enzyme Inhibitors / Q000302:isolation & purification*; D001467:Hordeum / Q000737:chemistry*; D010940:Plant Proteins / Q000302:isolation & purification*; D055315:Prolamins / Q000302:isolation & purification*; D000516:alpha-Amylases / Q000037:antagonists & inhibitors*
chemical_list: D004791:Enzyme Inhibitors; D010940:Plant Proteins; D055315:Prolamins; D000516:alpha-Amylases
keywords: Avenin-like protein-a; Barley dimeric α-amylase inhibitor-1; Beer; Foam stability