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zach1288 12-06-2012 01:36 AM

Difference between Proteins, Carbohydrates and Suagrs
 
I am looking for a simple description of proteins, carbohydrates and sugars in beer. I know that carbohydrates are found in starch and are converted to sugar in the mash but where do proteins come into play? I know that proteins as well as long chain sugars can contribute to mouth-feel. I'm just trying to break down and understand the "pieces" that make beer.

Thanks,
Zach

edds5p0 12-06-2012 02:08 AM

Quote:

Originally Posted by zach1288
I am looking for a simple description of proteins, carbohydrates and sugars in beer. I know that carbohydrates are found in starch and are converted to sugar in the mash but where do proteins come into play? I know that proteins as well as long chain sugars can contribute to mouth-feel. I'm just trying to break down and understand the "pieces" that make beer.

Thanks,
Zach

Carbohydrates are sugars and starches. Before enzymatic hydrolysis (mashing) starches are comprised of chains of simple sugars. After amylases work on them, they are broken down onto simple sugars (imagine single, double, and triple links) that yeast can ferment. Proteins are also chains, but they are made up of amino acids. Proteins contribute to head retention and somewhat to mouthfeel. Protein rests allow proteases, which break down amino acid chains, to work most efficiently. Proteins usually are lost to the hot break and cold break, but some remain and can cause chill haze.

dbsmith 12-06-2012 07:41 AM

Quote:

Originally Posted by edds5p0 (Post 4654035)
Carbohydrates are sugars and starches. Before enzymatic hydrolysis (mashing) starches are comprised of chains of simple sugars. After amylases work on them, they are broken down onto simple sugars (imagine single, double, and triple links) that yeast can ferment. Proteins are also chains, but they are made up of amino acids. Proteins contribute to head retention and somewhat to mouthfeel. Protein rests allow proteases, which break down amino acid chains, to work most efficiently. Proteins usually are lost to the hot break and cold break, but some remain and can cause chill haze.

While proteins are made from connected amino acids, describing them as a chain is not accurate. They are 3 dimensional molecules that perform a variety of functions, such as breaking down carbohydrates for energy by weakening chemical bonds/linkages, lowering activation energies for chemical reactions(catalyst), etc. Proteins carry out TONS of functions for cells. Virtually all of the cell's 'machinery' is made out of protein. For an enzyme to work properly, such as to break down starch into fermentable sugar, there are 3 things that must be in the right 'zone':
1-pH
2-Temperature
3-Substrate concentration (e.g. quarts water per pound of grain)

There are several different 'protein rests' that one can perform during the mash to optimize the quality of the wort. These rests are simply performed by maintaining the three things I mentioned above for a sufficient amount of time for the enzymes to do their job. Exceeding temperature can lead to denaturation, which will permanently deform the shape of the enzyme and thus not allow it to work properly.

ajdelange 12-06-2012 12:00 PM

It is not inaccurate to describe a protein as a chain of amino acids as that's exactly what it is. It may not be a complete description of a protein as the conformation of the chain is as important as the sequence of the particular acids in describing what the protein does and how it does it but it certainly is an accurate one. It would also be a good idea to mention bonds between links as they are a big part of what conforms a protein in a particular shape.

Would you say describing a starch as a chain of sugar molecules in inaccurate because they can link up in different ways?

zach1288 12-06-2012 02:07 PM

What is the purpose of protein in beer if most of it is lost to hot break and cold break? Does the beer need some protein?

I know that protein can cause chill haze but on the other hand you need it for head retention. Is there a balancing act in terms of this? Also flaked wheat and oats contribute more head retention and mouth feel than malted, why is this?

dbsmith 12-06-2012 03:05 PM

Quote:

Originally Posted by ajdelange (Post 4654785)
It is not inaccurate to describe a protein as a chain of amino acids as that's exactly what it is. It may not be a complete description of a protein as the conformation of the chain is as important as the sequence of the particular acids in describing what the protein does and how it does it but it certainly is an accurate one. It would also be a good idea to mention bonds between links as they are a big part of what conforms a protein in a particular shape.

Would you say describing a starch as a chain of sugar molecules in inaccurate because they can link up in different ways?

The chain idea is not an ideal description because it is the molecule's shape that enables the protein to do its task, such as weaken links between sugar monomers. You have to look at the big picture. There are all kinds of chemical bonds, such as disulfide bridges and ionic bonds, that connect amino acids to other ones that are not directly attached to each other via the ribosome to give the protein its shape. The idea of it being a chain is simplistic and does not convey how a protein works very well. For someone who wanted to know about proteins, it would be more useful for them to imagine it as a 3 dimensional molecule, rather than a simplistic 'chain'. As for the differing linkages in starches and any other kind of carbohydrate polymer, a new protein is often needed to break the bond, but the mechanism is the same. The protein will weaken the chemical bonds and allow it to break more easily. Though the carbon atom where the sugar monomers are linked is different for different carbohydrates, it is still a chain nonetheless. As for simple carbohydrates, while they can have different formations such as linear or ring shapes, the shape itself is not so important in terms of understanding its use in beer brewing. Additionally, simple carbohydrates can switch back and forth between linear and ring formations, whereas proteins never exist as a linear 'chain'. As soon as the ribosome begins to build the protein it begins folding and conforming into it's 3 dimensional shape. It never exists in any relative 2 dimensional 'chain' form.

edds5p0 12-07-2012 01:07 AM

Quote:

Originally Posted by dbsmith

The chain idea is not an ideal description because it is the molecule's shape that enables the protein to do its task, such as weaken links between sugar monomers. You have to look at the big picture. There are all kinds of chemical bonds, such as disulfide bridges and ionic bonds, that connect amino acids to other ones that are not directly attached to each other via the ribosome to give the protein its shape. The idea of it being a chain is simplistic and does not convey how a protein works very well. For someone who wanted to know about proteins, it would be more useful for them to imagine it as a 3 dimensional molecule, rather than a simplistic 'chain'. As for the differing linkages in starches and any other kind of carbohydrate polymer, a new protein is often needed to break the bond, but the mechanism is the same. The protein will weaken the chemical bonds and allow it to break more easily. Though the carbon atom where the sugar monomers are linked is different for different carbohydrates, it is still a chain nonetheless. As for simple carbohydrates, while they can have different formations such as linear or ring shapes, the shape itself is not so important in terms of understanding its use in beer brewing. Additionally, simple carbohydrates can switch back and forth between linear and ring formations, whereas proteins never exist as a linear 'chain'. As soon as the ribosome begins to build the protein it begins folding and conforming into it's 3 dimensional shape. It never exists in any relative 2 dimensional 'chain' form.

As a chemist, I am quite aware of this. My explanation was deliberately simplified to contribute to the OP's understanding of how enzymatic hydrolysis is relevant to beer production.

dbsmith 12-07-2012 01:18 AM

Quote:

Originally Posted by edds5p0 (Post 4657650)
As a chemist, I am quite aware of this. My explanation was deliberately simplified to contribute to the OP's understanding of how enzymatic hydrolysis is relevant to beer production.

I understand your point. I suppose that I imagined describing proteins as a chain would raise more questions than it would answer if I were trying to understand what they were. But that is certainly not true for everyone, and I also imagine that not everyone really wants a detailed description. :mug:

zach1288 12-07-2012 04:32 AM

Quote:

Originally Posted by zach1288 (Post 4655085)
What is the purpose of protein in beer if most of it is lost to hot break and cold break? Does the beer need some protein?

I know that protein can cause chill haze but on the other hand you need it for head retention. Is there a balancing act in terms of this? Also flaked wheat and oats contribute more head retention and mouth feel than malted, why is this?

:confused:

dbsmith 12-07-2012 05:55 AM

Quote:

Originally Posted by zach1288 (Post 4658327)
:confused:

The hot and cold break proteins are not required for a beer with good body and head retention. The hot break more or less is unavoidable, as it is caused by the rolling of the boil. The cold break makes certain proteins precipitate and drop out of suspension and allows a nice, clear beer. The proteins of the cold break are different from hot break proteins. I believe the break is high in tannins, which you most likely do not want in you beer. Cooling quickly also prevents infection. Wheat and oats are loaded with proteins. Wheat adds a nice starch haze to your beer. Unmalted grains and other adjuncts are primarily used because they can add characteristics to your beer relatively inexpensively. Why use expensive malted grains when you can use just a pinch of the unmalted form to still get the characteristics you are seeking? Unmalted wheat also has more of the original 'wheatiness' intact (higher protein content), since the endospore never began the germination process, which involves many biochemical reactions.


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