Lesson 10 - Maturation and Finishing End of Unit SAQ
You have now completed the Maturation and Finishing Unit. This lesson enables you to test yourself on the material covered and to determine the level to which you have met the learning outcomes. It will provide you the opportunity to test your knowledge with a last set of self-assessment questions.
Suggested Response - Q4
**Answer BOTH parts of this question:
You work in brewery that is in a very remote location in the tropics. There is a drive to become self-sustainable and significantly reduce co-products and waste on site.
a) What process measures would you consider in the maturation department?
b) What ingredient changes would you consider for your beers whilst not altering the beers flavour or aroma profile?
Response:
a) Sustainable processes benefit from low energy and consumable demand, and this would be a major driver for a brewery in the tropics. There are technologies available that would help deliver this agenda.
Brewers Clarex has significant sustainable benefits. It is a proline-specific endopeptidase enzyme that can specifically degrade the proline-rich proteins which contribute to haze formation in beer. It is added to the fermenting beer and degrades proteins throughout fermentation. As a result, one of the major benefits is that it negates the need for a cold maturation phase. Warmer conditioning temperature means cold conditioning is negated, so refrigeration demands are lower which leads to energy savings. Use of Clarex also negates the requirement for stabilisation process aids such as silica gel and PVPP due to the haze forming units being already depleted. In summary, the use of Clarex would have a favourable impact on both energy and consumable demands.
Crossflow filtration has very convincing sustainability benefits. Many medium sized and larger brewers are purposefully moving away from kieselguhr filtration, towards crossflow as it is more sustainable, especially in isolated areas of the world where spent kieselguhr costs are high. The benefits include:
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Lower operating expenditure as there is no need for DE
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As a result, no spent kieselguhr disposal costs
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No DE storage, handling or logistics required
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Sustainable method of filtration – lower water usage, lower carbon footprint and no process aids required
b) Depending on the reliability in the supply of raw material for this brewery’s location, the use of post-fermentation additions may benefit the brewer. It would also eliminate the need to remove spent materials at the end of process, such as hops.
A brewer may want to consider hop pellet alternatives which are dosed later on in the process. One option to consider is the use of isomerised hop extract to contribute bitterness to a beer. An iso-extract is a liquid solution that contains iso-α-acids in the form of potassium salts. This post-fermentation bittering (PFB) allows for increased hop utilisation because the bittering potential is not lost with trub, yeast cells or fobbing during fermentation. There are additional benefits of using isomerised hop extracts, these include light stability (protecting against light struck flavour), and beer foam can be significantly enhanced in the glass.
Secondly, hop oils can be added post-fermentation, to impart a fresh dry hop character. The advantage with aroma products is that they are completely soluble in beer and provide 100% utilisation in comparison to dry-hopping in cold storage, again reducing co-product which would otherwise require disposal.