Beer Brewing

Glossary

M

MAILLARD REACTION - A browning reaction, where situations of highly concentrated amino acids and reducing sugars exists producing compounds, collectively called melanoidins that provide the characteristic malty aroma and flavor to beers. Melanoidin production is most active in the malting process and continues to some extent in decoction mashing and to a somewhat lesser extent in boiling. For dark beers, it is important to use malt with a great deal of melanoidins already in it.

MALT - Barley or other grain that has been malted.

MALT EXTRACT - Wort that has been concentrated into a thick syrup or dry powder.

MALTING - The process of converting barley into malt by soaking, sprouting, and then germinating the barley (or other grain) to develop its enzyme content.

MALTOSE - A fermentable disaccharide of two glucose molecules, and the primary sugar produced by the breakdown of barley starch (diastatic hydrolysis of starch). It generally comprises 46 to 50 of the sugars in grain wort.

MANWAYS - Opening in tank that provides access to interior of tank.

MASH - A mixture of ground barley malt, cooked adjuncts (if used), and water that has undergone the conversion of grain starch to sugar.

MASH-IN - The initial stage of mashing; the process of mixing grist and water. It is also referred to as doughing-in.

MASHING - The process of mixing ground malt and cooked adjuncts (if used) with water in the mash tun to degrade haze-forming proteins and to further convert grain starches to fermentable sugars and non-fermentable carbohydrates (dextrins). The two main methods of mashing are infusion and decoction.

MASH-OFF - The final stage of mashing where the temperature is raised to about 76C to terminate enzymatic activity and improve flow of sugar solution.

MASH TUN - A vessel used for mashing as well as for wort separation.

MATURATION - Refers to maturing of beer flavor. A secondary fermentation may or may not be included.

MEALINESS - Hardness of kernels at completion of malting - soft mealy kernels indicate good modification.

MELANOIDINS - Dark colored organic compounds which form during kilning and wort boiling through a complex series of chemical reactions (called Maillard reactions) involving amino acids and sugars.

MODIFICATION - The physical and chemical changes occurring in barley during malting.