**Alcohol Content Measurement:**
– Alcohol by Volume (ABV)
– ABV measures ethanol content in alcoholic beverages.
– Defined as milliliters of pure ethanol in 100mL of solution at 20°C.
– Alc/vol is a globally recognized standard measure.
– In France, ABV is sometimes referred to as degrees Gay-Lussac.
– Alcohol proof and alcohol by weight are alternative methods of measuring alcohol content.
**Effects of Alcohol Content:**
– Volume Change with ABV
– Mixing alcohol solutions of different strengths alters volume.
– Partial molar volume explains volume changes.
– Water and ethanol attract due to polarity.
– Alc/vol differs from volume fraction (v/v).
– Max difference between alc/vol and v/v is less than 2.5%.
**Thresholds and Levels:**
– Legal thresholds exist for alcohol content in drinks.
– Some low-alcohol drinks are considered non-intoxicating.
– Healthy individuals find it hard to get intoxicated by low-alcohol beverages.
– Ethanol fermentation halts at a certain alc/vol level.
– Yeasts have tolerance limits for alcohol content.
**Typical Alcohol Levels in Beverages:**
– Various beverages have different typical alc/vol percentages.
– Alc/vol ranges from 0.05% in low-alcohol drinks to 95% in vodka.
– Different wines have alc/vol ranging from 5.5% to 25%.
– Spirits like rum, gin, and whisky have alc/vol ranging from 37.5% to 68%.
**Biological Impacts and Estimation Methods:**
– Low-alcohol drinks limit intoxication due to slow metabolism.
– Kidneys can excrete limited water per hour, affecting intoxication.
– Yeast tolerance sets upper limits for alc/vol in non-distilled drinks.
– Water intoxication risk may precede alcohol intoxication.
– Practical estimation of alcohol content involves fermentation and specific gravity measurement.
Alcohol by volume (abbreviated as alc/vol) is a standard measure of how much alcohol (ethanol) is contained in a given volume of an alcoholic beverage (expressed as a volume percent). It is defined as the number of millilitres (mL) of pure ethanol present in 100 mL (3.5 imp fl oz; 3.4 US fl oz) of solution at 20 °C (68 °F). The number of millilitres of pure ethanol is the mass of the ethanol divided by its density at 20 °C (68 °F), which is 0.78945 g/mL (0.82353 oz/US fl oz; 0.79122 oz/imp fl oz; 0.45633 oz/cu in). The alc/vol standard is used worldwide. The International Organization of Legal Metrology has tables of density of water–ethanol mixtures at different concentrations and temperatures.
In some countries, e.g. France, alcohol by volume is often referred to as degrees Gay-Lussac (after the French chemist Joseph Louis Gay-Lussac), although there is a slight difference since the Gay-Lussac convention uses the International Standard Atmosphere value for temperature, 15 °C (59 °F).