MEXCHEM2006 - 7-2-2007 at 10:38
I am going to start to work in a project that involves the crystallization of the sugars of the agave syrup , its chemical composition is :
fructose 87%
glucose 13%
Maybe someone with some experience in this field can give me some tips .
solo - 7-2-2007 at 13:53
PROCESS FOR THE OBTENTION OF FRUCTOSE AND FRUCTOSE-RICH SYRUPS
FROM XEROPHYTE PLANTS
Inventors: Enrique Zepeda-Castillo, deceased, late of Jalisco, by Isaura N. Vda, de Zepeda, executrix, Juan Bernardino 249, Guadalajara 5,
Jalisco, Mexico
United States Patent #4138272
Abstract
A process for the obtention of fructose and fructose rich
syrups from xerophyte plants, particularly of the
genus Amarillidaceae, such as Agave, comprises separately
collecting the plant material consisting of the leaf
portions and the core portions of the plant; admixing
and washing with water said plant materials; chopping
the washed plant material to form small pieces and
recovering the juices released, by the chopping operation;
subjecting the chopped material to an extraction
process with an aqueous liquor expressing the residual
solid plant material to expel the enriched extractant
therefrom; admixing the plant juice and extractant to
obtain a mixed juice, settling and clarifying said mixed
juice; acidulating the liquid phase of the process at a
preselected moment in the sequence, such that the settied
and clarified juice will be brought to a pH of from
about 3 to about 4; allowing said acidulated liquid phase
to stand for a period of time of from about 2 to 3 hours
at a temperature of from about 85' C. to the boiling
point; neutralizing the acidulated juice, clarifying the
filtered and neutralized juice, heating the clarified and
filtered juice, concentrating the heated juice by evaporation;
pasteurizing the concentrated juice whereby to
obtain a fructose-rich syrup; and crystallizing said fructose-
rich syrup to recover crystallized fructose therefrom.
Attachment: pat04138272.pdf (583kB)
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Reference Information
solo - 7-2-2007 at 16:02
Continuous crystallization
United States Patent 3981739
Abstract:
A crystallizable solute is crystallized from a solution containing the same by introducing a solution of said solute into a first stage
evaporative-crystallization zone together with seed solute crystals. Within the first stage evaporative-crystallization zone the solution is
concentrated to yield a saturated first stage concentrate containing crystals of said solute. The crystals of said solute are substantially larger
than said seed crystals and are suspended in a solution more concentrated with respect to said solute than the solution supplied to said first
evaporative-crystallization zone. A stream of said first concentrate is removed from said first evaporative-crystallization zone and transferred to a
second evaporative-crystallization zone for further concentration or crystallization of solute and for the production of solute crystals of increased
size. There is continuously recovered from the second evaporative-crystallization zone a slurry having a total solute or solids content of about 86-94
percent by weight and containing the solute crystals of desired crystal size.
Attachment: pat03981739.pdf (650kB)
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solo - 7-2-2007 at 16:09
Crystallization Kinetics of Lactose and Sucrose Based On Isothermal Differential Scanning Calorimetry
C.J. KEDWARD, W. MACNAUGHTAN, J.M.V. BLANSHARD, J.R. MITCHELL
Journal of Food Science 63 (2), 192–197.
ABSTRACT
Isothermal Differential Scanning Calorimetry (DSC) was used to study the crystallization kinetics of freeze-dried samples of lactose and sucrose at
several temperatures between Tg and Tm. The sample was rapidly heated to the required temperature. After subtraction of an induction time, the Avrami
equation was used to model the data and a Lauritzen-Hoffman like expression used to fit the derived rates of crystallization over the temperature
range Tg<T<Tm. For both sugars the maximum rate of crystallization occurred at a temperature slightly higher than the midpoint of Tg and Tm.
Crystallization rates were higher for lactose than sucrose. This could be explained by simple changes in Tg and Tm which could be accounted for by
differences in moisture content.
Attachment: Crystallization Kinetics of Lactose and Sucrose Based On Isothermal Differential Scanning Calorimetry .pdf (142kB)
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Ozone - 7-2-2007 at 16:58
This can actually be kind of tricky. Do you want pure fructose or is the mix OK? We do this sort of thing at work, sucrose, glucose, fructose,
tagatose, etc.
Fructose is inherently difficult to crystallize as solutions are stable in excess of 90% in dry solids. But...glucose is only stable below 50 (or so)
% on dry solids...
From my well loved copy of : Pigman, W. The Carbohydrates: Chemistry-Biochemistry-Physiology. (1957). Academic Press, Inc. QD 321 p624c.1, pp. 95.
"The separation of the ketose from the concomitant D-glucose then may be accomplished by direct crystallization, by removal of the D-glucose after
oxidation with Bromine to D-gluconic acid (ketoses are not effected), or by precipitation of the Calcium fructosate."
Or, you could precipitate the whole works with ethanol (glucose should fractionate first).
Cheers,
O3
Reference Information
solo - 7-2-2007 at 20:08
PROCESS FOR THE CRYSTALLIZATION OF GLUCOSE, FRUCTOSE, OR MIXTURE OF GLUCOSE AND FRUCTOSE
Kazuo Hara and Mistunobu Samoto, Yokohama, Masanobu Sawai, Yamato, and Shiro Nakamura
US Patent #3704168
http://mihd.net/nfpbl3
Abstract
A process for the crystallization of glucose, fructose, or a mixture of the two, which is characterized in that the crystallization is performed in
the presence of a combination medium of a liquid polyhydric alcohol and liquid monohydric alcohol as the crystallization medium.
chemoleo - 7-2-2007 at 20:55
Solo, just to say, awesome you are posting this, and to point out it doesnt go unnoticed, please keep going.
You pretty much answered his question just by your references.
MEXCHEM2006 - 8-2-2007 at 09:20
Thank you for the patents Solo , sometimes patented process dont work , for example this patent:
PROCESS FOR THE OBTENTION OF FRUCTOSE AND FRUCTOSE-RICH SYRUPS
FROM XEROPHYTE PLANTS
Inventors: Enrique Zepeda-Castillo, deceased, late of Jalisco, by Isaura N. Vda, de Zepeda, executrix, Juan Bernardino 249, Guadalajara 5, Jalisco,
Mexico
United States Patent #4138272
I tried to make agave syrup following the patent instructions and it did not work , but the good thing is that i came up with a new process
roamingnome - 8-2-2007 at 10:06
many people have suggested that some patents can be a crap shoot.
Indeed patents are more about paying money so you can patent a flying saucer esspresso machine that doesnt work, but if you pay all the fees theyll be
glad to "patent" it for you. In the old days patents seemed much more relavant, but i think they are obsolete these days.....
i tend to think chemical patents should work though... in what way did this fail?? just out of curiosity... was any compromise made or subsitution
done?
MEXCHEM2006 - 8-2-2007 at 10:35
For example they say that you have to heat to 100ªC after filtering and clarifying the juice , if you do this you will end up with a bitter dark
juice.
Ozone - 8-2-2007 at 17:41
Are you clarifying the juice with lime? What exactly are you doing (process-wise) and at what scale? At 100°C and alkaline pH you will absolutely
make what we call "hexose alkaline degradation products"(HADP); this process is *fast*. If acidic, you will be going the caramel-Maillard route (slow)
and, if intermediate, viz. 7-8.5 you should get primarily Maillard products. All save the caramels are notoriously bitter. HADPs are bitter, Maillards
vary significantly depending on the carbohydrate and the amino acid/amine and can range from floral to bitter to burnt; smoky/bitter is most common
(think burnt chicken skin on the grill).
Note that caramel and Maillard formation follows Arrhenius kinetics quite well, and the take-off point is at ~50%solids, 95°C (exponential after this
point). The HADP's form nicely at low brix (% dry solids).
Cheers,
O3
MEXCHEM2006 - 9-2-2007 at 09:30
Yes i am clarifying the juice with lime, we make 1 ton per day of agave syrup, and the process involves:
1.- Collect the leaf and core portions of the agave tequilana.
2.- Extraction of the juice.
3.-Clarifying the juice.
4.- Anion exchange resins.
5.-Cation exchange resins.
6.-Activated carbon column
7.-Hidrolysis with acids and heat.
(.- Vacuum evaporation
Maya - 9-2-2007 at 11:49
Why don't you put #6 between #3 and #4?
And you can also have a mixed bed resin which will combine #5 and #4 into one step!
[Edited on 9-2-2007 by Maya]
[Edited on 9-2-2007 by Maya]
Ozone - 9-2-2007 at 18:05
Yes, Iv'e had really good results with mixed beds, *but* mixed beds, viz. "softening resins" are notoriously difficult to regenerate.
OK, MEXCHEM2006, you are running a standard decolorizer (and de-ashing) procedure. Possible problems may include:
The temperature you operate at; generally, these operations are run at ~85°C to prevent microbical infestation, particularly Leuconostoc, which will
(via dextransucrase) cleave your sucrose and make a polycglucan from the glucuse (they will eat fructose making mannitol when out of their preferred
food). This is good microbiologically but *bad* chemically, particularly at low pH which brings us to the cationic resin...
Generally the deashing section, the cationic resin is an industrially feasible way to produce invert sugar. For sucrose rich solutions (when you wish
to deash, but also wish to keep sucrose intact) these sections are run under refrigeration (the cold keeps the inversion from occuring). This is
usually output to the anionic resin section which is also run hot (but usually suffers because it follows, directly, a refrigerated unit-operation).
OK, looking at your scheme, and knwoning that you want invert
(I always have to
save the sucrose), I would:
1. Express and collect the juice
2. Clarify the juice under hot lime conditions (100-110° with flash; the solubility of Ca(OH)2 goes *down* as the temperature goes up. The
clarification is not as good as under intermediate liming, but there is much less added ash to deal with (see Eggleston, G., numerous papers in the
International Sugar Journal, SPRI, etc.; hot-liming is her thing). Addition of up to 5ug/mL of anionic flocculent will *greatly* enhance both the rate
of floc settling (see "mud conditioning"). Watch the pH! It should not exceed ~7.2, tops. Back correction with phosphoric acid is effective.
3. Make sure your juice is around 80-100°C aand pass it through your cationic resin (this will deash and invert your sucrose and other oligos).
4. Run though the anionic resin (which is mainly a decolorizing resin--what form is your anionic resin in? you may not even need this.) and the carbon
(make sure the outgoing jucie is not still acidic, GAC usually drops the pH a bit, and is often fortified with magnesite to avoid this). The carbon
polisher will remove the HADP, caramel and Maillard products made a a consequence of processing.
Be sure to evaporate under vacuum or color (most of your color formation will occur between evaporation and crystallization stages, and concomittant
sugar loss) will result! Look up multiple-effect evaporators (or Rillioux, Norbert) for how the evaporation is done industrially (really quite cool
how it works).
Keep me posted,
O3
MEXCHEM2006 - 10-2-2007 at 07:30
Many thank`s for the info but my process works very fine , i only wanted to point out that some patents on this process dont work, i am allready
selling my product to japan and the U.S.A.
Related Reference Information (good Reading )
solo - 10-2-2007 at 18:27
2002 SPRI CONFERENCE
ABSTRACTS OF PRESENTATIONS MARCH 10-13, 2002
Attachment: the sugar spirals.pdf (270kB)
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