Beer organoleptic and microbiological quality [ LBRAL2101 ]

Icampus

Brewing chemistry, Food technology, Food microbiology

The different kinds of beer and the ways to produce them will be defined.

The student will then learn how to conduct the sensorial analysis of a beer. This will help him to identify the chemical and biochemical steps of the manufacturing process which could be improved. Theoretical data relative to water and foam quality will be also given.

The following themes will be discussed during the experimental sessions : visual parameters of a beer, quality of the water, aromas of malt, amber and brown beers, low-alcohol beer flavors, hop bitterness and aromas, fermentation aromas, sulfurous aromas, off-flavours in aged beers.

The contaminants (yeasts, bacteria and molds) being able to develop in a beer will be described, as well as the available technical ways to avoid the development of microorganisms at the "critical points" of contamination. Description of the various chemical and physical treatments applied (pasteurization, sterile filtration). Controls to make in the brewery since raw materials up to the finished product.

The course contributes to the following learning outcomes : 1.1, 1.3, 1.4, 1.5 + 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9 + 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9 (BIRC21)

At the end of this course, the student will be able to

- conduct sensorial analyses on different kinds of beers,

- describe the organoleptic qualities and defects of a beer,

- recognize the different microorganisms able to develop in beer,

- develop strategies allowing to avoid such problems.

Written examination. Oral presentation of a type of beer and its recipe.

The different types of beers associated to particular modes of production will be presented by groups of students.

The student will then learn how to experimentally conduct a sensorial analysis, this to identify the chemical and biochemical stages of the brewing process which could modify the beer flavors. Theoretical courses on water quality and foam stability will complete the experimental sessions.

The following themes will be discussed during the experimental sessions : visual parameters of a beer, quality of the water, aromas of malt, amber and brown beers, low-alcohol beer flavors, hop bitterness and aromas, fermentation aromas, sulfurous aromas, off-flavours in aged beers.

The contaminants (yeasts, bacteria and molds) being able to develop in a beer will be described, as well as the available technical ways to avoid the development of microorganisms at the "critical points" of contamination. Description of the various chemical and physical treatments applied (pasteurization, sterile filtration). Controls to make in the brewery since raw materials up to the finished product.