page_title: Tequila
section_title: Alcohol content
hierarchical_section_title: Tequila / Chemistry / Alcohol content
caption_attribution_description: English: Saccharomyces cerevisiae cells in DIC microscopy. Imaging was performed with the Olympus BX61 microscope and a UPlanSApo 100× NA 1.40 oil immersion objective (Olympus). Pictures were acquired at room temperature in synthetic complete medium with a camera (SPOT; Diagnostic Instruments, Inc.) using MetaMorph software (MDS Analytical Technologies). Polski: Komórki drożdży piekarniczych (Sacharomyces cerevisiae) widziane w różnicowej mikroskopii interferencyjnej. Zdjęcie wykonane w syntetycznej pożywce kompletnej za pomocą mikroskopu Olympus BX61 wyposażonego w obiektyw imersyjny (olej) 100x NA 1,40 (Olympus) sprzężonego z kamerą SPOT (Diagnostic Instruments, Inc.). Użyto programu MetaMorph software (MDS Analytical Technologies).
context_page_description: Tequila is a distilled beverage made from the blue agave plant, primarily in the area surrounding the city of Tequila 65 km northwest of Guadalajara, and in the Jaliscan Highlands of the central western Mexican state of Jalisco.
  The red volcanic soils in the region of Tequila are well suited for growing the blue agave, and more than 300 million of the plants are harvested there each year. Agave grows differently depending on the region. Blue agaves grown in the highlands Los Altos region are larger and sweeter in aroma and taste. Agaves harvested in the lowlands have a more herbaceous fragrance and flavor. Due to its historical and cultural importance, the region near Tequila was declared a UNESCO World Heritage Site in 2006, the Agave Landscape and Ancient Industrial Facilities of Tequila.
  Mexican laws state that tequila can only be produced in the state of Jalisco and limited municipalities in the states of Guanajuato, Michoacán, Nayarit, and Tamaulipas. Tequila is recognized as a Mexican designation of origin product in more than 40 countries.
context_section_description: Tequila is a distilled beverage that is made from the fermentation of the sugars found from the blue agave plant once it has been cooked, the main sugar being fructose. Through the fermentation process, many factors influence the higher alcohol content of tequila, which are molecules such as isobutyl alcohol and isoamyl alcohol, and ethanol. These parameters include the type of yeast strain, the age of the agave plant itself, temperature, and the carbon:nitrogen ratio. 
  However, the type of yeast strain used and the carbon:nitrogen factors have the biggest influence on the production of higher alcohols; this is not surprisingly as higher alcohol and ethanol production is an intrinsic property of the metabolism of each strain. The type of yeast most commonly found in tequila is Saccharomyces cerevisiae, which contains many strains. For example, CF1 agaves, a type of yeast, produces much more ethanol than a strain of CF2, as the two yeasts' metabolism mechanisms differ. This factor may be influenced from different agricultural practices that occur to cultivate the different yeasts strains. It was found that the higher the carbon:nitrogen ratio, the higher the production of higher alcohols such as isobutyl alcohol and isoamyl alcohol. A high ratio imparts that there is less nitrogen in the fermentation process, which results in deamination reactions of amino acids, leading to the synthesis of higher alcohols. The Ehrlich pathway is the name for this process, where alpha-keto acids are decarboxylated and transformed to aldehydes and to higher alcohols. 
  The temperature of the fermentation process also greatly effects the alcohol content of the resulting product. For example, a study conducted by Pinal et al. found that cultivating two strains at a temperature of 35 degrees as compared to a temperature of 30 degrees produced more isoamyl alcohol. The higher temperature suggests that this is a much more optimal condition for the yeast to ferment the distilled beverage. 
  Lastly the age of the agave plant itself: the older the plant, the greater the alcohol production. It was shown in a study that the concentration of amyl alcohol increased as the plant aged by a factor 30%. However, a higher concentration of methanol is found when using younger plants. This may be due to differences in agricultural practices that occur when taking care of plants of different ages.
caption: Saccharomyces cerevisiae, under a microscope
exif: {"Image Software": "ACD Systems Digital Imaging", "Image DateTime": "2019:03:04 00:04:17", "Image ExifOffset": "98", "EXIF SubSecTime": "958"}