Alkaline　extraction　is　an　important　process　in　the　integrated　biorefining　of　leafy　biomass　to　obtain　protein,　but　the　resulting　alkaline　protein　extract　(APE(1))　may　have　poor　emulsification　properties　for　food　applications.　In　this　study,　the　components　in　the　APE　fractionations　obtained　by　size　exclusion　chromatography　were　deter-mined.　The　emulsification　properties　of　APE　were　determined　using　oil/water　with　a　ratio　of　7:3.　Whey　protein　and　soybean　protein　isolate　were　used　as　controls　while　enzymes　were　used　to　improve　APE＇s　emulsification　properties.　The　results　showed　that　the　APE　could　be　divided　into　three　fractions　with　protein　content　of　83,　56,　and　34%.　Carbohydrates　mainly　derived　from　homogalacturonan　pectin　were　mostly　in　Fraction　2,　while　Fraction　3　consisted　of　peptides,　oligosaccharides,　and　free　polyphenols.　The　APE　had　similar　emulsification　capacity　and　emulsification　stability　as　those　of　whey　protein　and　soybean　isolate.　The　emulsion　made　by　the　APE　had　a　creaming　index　of　92%　with　emulsification　activity　index　value　of　44　m(2)　g(-1),　and　these　numbers　could　retain　after　storing　at　25　C　for　15　days.　The　emulsification　properties　of　the　APE　can　be　further　improved　by　carbohydrate　degradation.　With　the　use　of　Viscozyme　(R)　L,　the　emulsification　activity　index　value　of　treated　APE　was　increased　by　60%,　and　then　still　retained　at　67　m(2　)g(-1)　after　storing　for　15　days.　Treated　by　either　pepsin　or　alkaline　protease,　the　emulsification　properties　of　APE　were　decreased,　suggesting　the　key　role　of　protein　in　APE　for　emulsification.