Using ethelyne gas to convert starch to sugar

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Discussion Overview

The discussion centers on the potential use of ethylene gas to convert starch in flour into sugar, drawing parallels with its application in ripening fruits. Participants explore whether a flour paste exposed to ethylene could yield a sugary solution and consider the implications of particle size and exposure time. The conversation shifts towards the use of amylase enzymes as an alternative method for starch conversion, particularly in the context of extracting sweet sap from shredded palm tree material.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • Some participants propose that ethylene gas could convert starch to sugar in flour, similar to its effect on fruits.
  • Others argue that ethylene will have no effect on dead or processed plant materials like flour, suggesting that enzymes like amylase are necessary for starch conversion.
  • One participant inquires about the effectiveness of amylase at room temperature (25°C) and whether time and agitation could enhance the conversion process.
  • Another participant suggests that while gentle agitation may help, excessive agitation could inactivate the enzymes.
  • One participant shares their research context involving the extraction of sweet sap from palm trees and discusses the potential for using amylase to convert remaining starches in shredded material before processing.
  • A later reply recommends considering cellulase enzymes for breaking down wood fiber in the context of the proposed process.

Areas of Agreement / Disagreement

Participants generally agree that ethylene gas is not suitable for converting starch in flour, with a consensus on the utility of amylase enzymes. However, there remains uncertainty regarding the optimal conditions for starch conversion, including temperature and time, as well as the effectiveness of different types of amylase.

Contextual Notes

Limitations include the dependence on specific enzyme types and their optimal conditions, the need for empirical testing to determine conversion efficiency, and the potential variability in results based on agitation methods.

Who May Find This Useful

Researchers and practitioners in food science, enzymology, and agricultural processing may find this discussion relevant, particularly those interested in starch conversion and sap extraction techniques.

mellotango
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It is commonly known in the fruit industry that ethylene gas is widely used to boost a fruit's ripeness. i.e. fruits are harvested when they are still unripened, but prior to selling them on the market, they are exposed to a dose of ethylene gas, which are fruit's hormones to convert its internal starch to sugar. Hence, the sweet taste of ripened fruits.

I would like to know if the same effect can be applied to flour such as wheat flour, corn flour, etc. Would a flour paste i.e. flour mixed with water, and exposed to ethylene gas convert the starch to sugar? And therefore a sweet sugary solution (mainly glucose) can be extracted after this process.

And since flour is in small particles, would stirring the flour paste in presence of ethylene gas to convert it to sugar be an almost instantaneous conversion? As compared to ethylene gas on fruits, which could take 24 hours or more due to its size as a whole fruit as well as exposure to ethylene gas only on the outside skin surface of the fruit?

Thx in advance for your answer.
 
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No. As you mention, ethylene acts as a hormone that tells the plant cells to begin producing the enzymes required to break starch into sugar. In preparations where the cells are dead or removed, such as flours, ethylene will have no effect.

There are enzymes that you can add to starch solutions that will convert the starch into sugar, such as amylase. In fact, our saliva contains amylase, which is why starches will begin to taste slightly sweet if you chew them enough. There are also chemical means of breaking down starches (although these generally are not as efficient and produce dextrins instead of simple sugars).
 
Ok, so the key would be to add amylase instead of ethylene gas. I had thought about it but aware that amylase worked best at an optimal temperature of 60C thereabouts. Now if I didn't have the luxury of a 60C temp, but only room temperature amylase solution of 25C, would the starches be eventually converted fully to sugar given enough time? Would a few hours or overnight be a good estimate? If I can't control the available temperature, I could control other areas such as providing it constant agitation. Would agitation increase the rate of which starch will be converted to sugar at a shorter duration?
 
I don't know which amylase enzymes are commercially available, but I'd think you could find an enzyme that acts optimally around room temp or slightly above room temp (e.g. 37oC). As to the conditions required for full conversion, you'd probably have to search the literature/perform some pilot experiments to figure that out. Gentle agitation of the solution would probably help the reaction by keeping the solution well mixed but agitation that is too vigorous can inactivate the enzymes.
 
That's interesting to know there are such amylase enzymes that work optimally close to room temperature. I'll definitely try to find out more about it. Usually both types of alpha and beta amylases are needed to break down starch to sugar. I'll see if there are both types that work around room temperature.

To fill you in more, I'm actually research the process to extract sweep sap from old palm trees. The palm trunks are shredded finely before it sent to a roller mill to extract the juice. The shredded trunks actually consists a generous portion of starch and the rest is fibrous woody material, hence the sweet sap. But I'm trying to see whether we can use amylase to convert remaining starches in the shredded material into sugar before it gets to the roller mill. All this must be done at normal outside temperature to reduce processing costs. Hence, I'm trying to figure out the wait time for most of the starches to convert to sugar. And as for agitation, we are trying to use a long and slow screw conveyor to feed the material into the roller mill, so hopefully by the time it reaches the mill, the shredded material is nicely agitated and most of the starch convert to sugar by then.

Any feedback or opinions on our proposed process would be greatly appreciated. Thx
 
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Try using cellulase on that wood fiber.
http://www.enzyme-india.com/cellulase-enzymes-dietetic.html
 
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