Malted grains are just about the most important ingredient in beer. That is why all brewers look for the best malt. If your beer did not turn out 100% what you expected it to be, then the malt quality will have something to do with it surely? To be honest, it usually doesn't. But to make a really good choice, it is important to understand what is written on a malt specification sheet. You can download those spec sheets for all our malt products. Let's go through the most important and most common parameters of such a specification sheet and explain what they mean.
On the specification sheets, the terms "upper" and "lower supply limits" or "min." and "max." usually refer to the range within which the values of the various parameters fall. These limits indicate the minimum and maximum values that can be expected for certain properties of the malt.
1. Moisture
This is the percentage of water in the malt. A lower moisture level means the malt has a longer shelf life and less chance of mould or bacteria. Typically, this is around 4-6%. The moisture level also impacts the malt's crushability. Too high a moisture level makes it harder for the grains to break, leading to less efficient sugar extraction. Furthermore, excessive moisture levels also affect the consistency of enzyme action and can additionally cause unnecessary weight.
2. Colour
EBC (European Brewery Convention) and Lovibond (1 Lovibond roughly corresponds to 2.65 EBC): these indicate the colour of the malt, which ultimately affects the colour of your beer. EBC is common in Europe, while Lovibond is used more in the US. A lower value means a lighter malt, and a higher value means a darker malt.
This is the colour of the wort after boiling and may vary slightly from the original colour value of the malt. It helps you understand what your beer will look like after boiling, because although the EBC or Lovibond values of malts are a good starting point, chemical reactions during boiling can affect the final colour of the beer.
4. Extract fine dm
This indicates how much sugar can be extracted from the malt per kilogram of dry malt. A higher percentage means more sugars available for fermentation. "Extract fine dm: 80%" means that 80% of the dry matter in the malt can be converted into fermentable sugars.
5. Fine and coarse grind extract difference
This shows the difference in extraction efficiency between finely and coarsely ground malt. A smaller difference means better extraction efficiency. This is an important parameter for brewers as it affects how well sugars are extracted from the malt during mashing. The difference can help optimise the grinding process to achieve efficient sugar extraction and understand how grind size affects the final quality and yield of your beer.
If you grind finely, it can increase your extraction efficiency because of the larger surface area for enzymatic reactions, but there is also a chance that you will have problems when filtering because your filter bed will clog up. Therefore, experiment with different grind sizes to see which offers the best balance between extraction efficiency and filtration ease.
6. Soluble protein
These are the proteins that dissolve in the wort. Soluble proteins help form foam and maintain the head on the beer (but beware, too many soluble proteins will just have a detrimental effect on foam stability). They can also contribute to the beer's turbidity if they start to react with other components such as polyphenols. The right level of soluble proteins helps achieve a clear beer. Typically this will be around 4-5%.
7. Kolbach Index
This is the ratio of soluble protein to total protein, expressed as a percentage. It helps assess protein modification and affects the clarity, mouthfeel and foam stability of the beer. Thus, a higher Kolbach Index percentage indicates well-modified malt. This means that the proteins and starch have been sufficiently broken down during malting, allowing more efficient conversion during mashing. Well-modified malt facilitates enzymatic activity during mashing, allowing more efficient extraction of sugars from the malt.
8. Friability
This measures how easily the malt grains break when ground. Well-modified malt grains tend to be more brittle, meaning they break more easily, and their starch and enzymes are more readily available for the brewing process. Good breakability (>80%) means more efficient extraction of sugars during mashing.
9. Wort Viscosity
This indicates the viscosity of the wort. A lower viscosity is better because it makes the mashing and filtration process smoother.
Low Viscosity (below 1.5 cP): indicates a thin wort that flows easily through the filter bed, resulting in fast filtration and an efficient brewing process. However, too thin wort can sometimes lead to lower extraction efficiency.
Optimal Viscosity (between 1.5 and 2.5 cP): indicates that the wort has the right balance between flowability and sugar extraction. This ensures efficient filtration and a good sugar yield.
High Viscosity (above 2.5 cP): indicates a thick wort that flows more slowly through the filter bed. This can reduce the filtration rate and cause problems in wort clarification.
10. pH of the wort
The pH value of malt is an important parameter that has a significant influence on the brewing process and beer quality. It refers to the acidity or alkalinity of the extract obtained when malt is dissolved in water. The pH of the malt has a direct influence on the pH of the mash. Since an optimal mash pH (between 5.2 and 5.6) is crucial for enzymatic activity and the efficiency of the starch conversion process, it is sometimes useful to know the pH of the malt used.
11. Free Amino Nitrogen (FAN)
Free Amino Nitrogen (FAN) is a measure of the amount of available amino acids and small peptides in the wort. These nitrogen compounds are essential for the growth and health of yeast during fermentation. Measuring FAN helps brewers ensure that enough nutrients are present to support healthy and efficient fermentation. A good value is usually between 120-240 mg/l. Too low values can slow down fermentation, while too high values can promote unwanted flavours such as diacetyl. If the FAN values are too low, the brewer will have to add yeast nutrients.
12. Diastatic power (DP)
This measures the enzyme activity in the malt, which is needed to convert starch into sugars. A higher DP means more active enzymes and more efficient starch conversion. Use a mix of malts with high DP (>300 °WK) and malts with low (<100 °WK) or no DP to ensure a balanced mash. Make sure you use enough base malts to support enzymatic activity.
13. Beta Glucan in Wort
Beta-glucans are a type of polysaccharides, or complex sugars, found in the cell walls of barley and other cereals. In the brewing process, they are important because they can affect the viscosity of the wort and the filtration process. Lower is often better, usually below 200 mg/l.
14. Hartong Index 45°C
This measures enzyme activity at a lower temperature (45°C) and gives an indication of malt modification. It is an additional measure of diastatic power.
15. Saccharification time
This is the time it takes for starch to fully convert into sugars. Shorter is better, typically less than 20 minutes.
16. Glassy Kernels
These are incompletely modified malt grains that are harder and more difficult to grind. Vitreous grains occur during malting when certain parts of the grain are less well processed, giving them a glassy and translucent appearance. This often happens due to insufficient or uneven germination of the malt. A lower percentage (<5%) is always better.
Your informed choice
Understanding these specifications will help you make informed choices or avoid potential problems during brewing. Take the time to study the specification sheet of your chosen malt before resorting to the killer phrase "it must be the malt".