Unmalted Adjuncts Flashcards
What are unmalted adjuncts?
Solid cereals that require enzymes to convert their starch into dextrins and fermentable sugars.
What is the purpose of processing unmalted adjuncts?
To make the starch available for conversion.
What components are typically removed during the processing of cereals for adjuncts?
The embryo and any husk material.
What is the main goal of further processing some unmalted adjuncts?
To increase the proportion of starch and make it easier to convert in the brewhouse.
What are the three steps in the conversion of starch into sugar during brewing?
- Gelatinisation
- Liquefaction
- Saccharification
What happens during gelatinisation?
Starch granules unwind to expose individual glucose chains to enzymes.
What is the result of liquefaction in the starch conversion process?
The hydrolysis of starch chains catalysed by enzymes, turning the gel into a liquid.
What is saccharification?
The further hydrolysis of liquefied starches to produce sugars.
What two elements are required for gelatinisation to occur?
- Moisture/water
- Thermal energy
What does the gelatinisation temperature of starch granules dictate?
Where in the brewing process you can use the adjunct.
Which cereals require cooking due to their gelatinisation temperatures?
- Maize
- Rice
- Sorghum
What is the gelatinisation temperature range for barley?
75-80°C
True or False: The gelatinisation temperature for rice is lower than that for maize.
True
What is the role of malted barley in cereal cooking?
To provide some enzymes that will start the liquefaction of the starch.
What can be used instead of malted barley to aid in the liquefaction of starch?
Commercial (exogenous) enzymes.
What happens to diastatic enzymes when exposed to high heat directly?
They will be denatured.
What protects the diastatic enzymes in the mash during cooking?
The thick cereal mash.
What is the main form of unmalted adjuncts used in breweries?
Grits.
Fill in the blank: The gelatinisation temperature of starch granules is influenced by _______.
[the nature of the starch]
What is the impact of removing the germ during maize grit production?
Reduces the lipid content significantly.
Which cereal has the highest protein content as an adjunct?
Wheat
What is the protein content of maize as an adjunct?
9.8%
What is the gelatinisation temperature range for oats?
55-56°C
What is the size range of barley starch granules?
1-25 µm
