Water activity 水分活度 >Water is required for the growth and metabolism of microorganisms 水是微生物生长和新陈代谢必需的物质 All the water in foods is not available for microorganisms 并非食品中的水分都能被微生物利用 The degree of availability of water is measured by water activity (a w) 用水分话度āw衡量有效水分的含量 Chemical and enzymatic reactions are also affected by availability of water 化学反应和酶反应也受有效水分的影响 18 窗中18 ➢ Water is required for the growth and metabolism of microorganisms 水是微生物生长和新陈代谢必需的物质 ➢ All the water in foods is not available for microorganisms 并非食品中的水分都能被微生物利用 ➢ The degree of availability of water is measured by water activity (a w ) 用水分活度a w 衡量有效水分的含量 ➢ Chemical and enzymatic reactions are also affected by availability of water 化学反应和酶反应也受有效水分的影响 Water activity 水分活度