Agaves as a raw material: recent technologies and applications.

Abstract

Agave plants are a valuable source of raw material due to its fibrous and complex sugar content of their leaves and core, and their bagasse waste can be use for several aims. This plant genus belongs to the Agavaceae family and until now more than 200 species have been described. A large number of Agave species are currently used as raw material in several biotechnological processes. This review shows the reported applications and patents on fields like alcoholic brewages with special reference to Tequila and Mezcal, the isolation and use of compounds such as saponins and agave fructans, and their potential biotechnological application on several human demands. The process to obtain fibers and cellulose, stock feeds, and several miscellaneous extractives are also reviewed. Some possibilities and problems of cultivation are discussed.

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Recent Patents on Biotechnology 2009, 3, 185-191
185
1872-2083/09 $100.00+.00 © 2009 Bentham Science Publishers Ltd.
Agaves as a Raw Material: Recent Technologies and Applications
Narváez-Zapata J.A.1,* and Sánchez-Teyer L.F.2
1Centro de Biotecnología Genómica - Instituto Politécnico Nacional;
Investigación Científica de Yucatán A.C.
2Unidad de Biotecnología, Centro de
Received: June 23, 2009; Accepted: June 28, 2009; Revised: July 30, 2009
Abstract: Agave plants are a valuable source of raw material due to its fibrous and complex sugar content of their leaves
and core, and their bagasse waste can be use for several aims. This plant genus belongs to the Agavaceae family and until
now more than 200 species have been described. A large number of Agave species are currently used as raw material in
several biotechnological processes. This review shows the reported applications and patents on fields like alcoholic
brewages with special reference to Tequila and Mezcal, the isolation and use of compounds such as saponins and agave
fructans, and their potential biotechnological application on several human demands. The process to obtain fibers and
cellulose, stock feeds, and several miscellaneous extractives are also reviewed. Some possibilities and problems of
cultivation are discussed.
Keywords: Agaves, tequila, sisal, agave fructans, saponins.
INTRODUCTION

of Mexico, as it has been useful for a wide range of appli-
cations among Mexican cultural development, from alimen-
tary purposes to medicinal, religious, textile, construction,
and even ornamental ones [1, 2]. The genus belongs to the
order Asparagales and to the Agavaceae family, and more
than 200 species plus 47 infraspecific categories have been
identified, from which 75% are found in Mexico, being this
country the center of origin of this genus [3, 4]. There are
around 135 species of Agave endemic to Mexico [2].
Agave genus has a millenary relationship with the history

rages such as Mezcal (A. angustifolia; A. potatorum; A.
salmiana), Sotol (A. dasylirion; Dasilyrion ssp.), Bacanora
(A. angustifolia; A. potatorum; A. pacifica), Pulque (A. sal-
miana), and Tequila (A. tequilana). Natural aguamiel or
juices obtained from cores or “piñas”, fresh or cooked, can
be used to obtain polysaccharides, agave fructans, high fruc-
tose syrup, biofuel or Maillard compounds. Agave fibrous
wastes also can be used as source of paper-making fibers and
fertilizers.
Some agaves are mainly used to produce alcoholic beve-

has been largely basic emphasis. Commercial research has
been essentially conducted to optimize ancient processes and
recently to development new and promissory technologies to
use specific biomolecules of these desert plants. Conside-
rable development opportunities still exist and provide a
future position of economic importance for Agave plants.
Applied research on agave plants during the past decades
AGAVE AS A SOURCE OF SPIRIT BEVERAGES

and its raw material is restricted by law to the blue Agave (A.

*Address correspondence to this author at the Centro de Biotecnología
Genómica-Instituto Politécnico Nacional. Blvd Del Maestro esq. Elias Piña,
Col. Narciso Mendoza 88710, Reynosa, Tamaulipas (Mexico); Tel : +52
(55) 57 29 6000; Ext. 87730; Fax: +52 (55) 57 29 6000; Ext: 87740;
E-mail: jnarvaez@ipn.mx
Tequila is the Mexican liquor most consumed worldwide,
tequilana Weber var. Azul), at specifically designate geogra-
phic areas, primarily the state of Jalisco in west-central Mex-
ico [5]. An agave plant has two main parts: the long spiked
leaves from which sisal-type fibers can be obtained, and the
“core” or “piña” from which cooked (or baked) juices are
extracted for tequila production. To produce Tequila, [6]
provide the complete improvement process, beginning with
cooking piñas for at least 32 h at 100 °C. The agave-juice
obtained from cooked and crushed piñas is then fermented
and double-distilled to generate white Tequila. This product
can be matured from 3 to 12 months in oak casks to produce
rested tequila or from 1 to 5 years to produce aged Tequila
[7]. Tequila is usually bottled in one of five categories:
White (“blanco"), bottled and stored immediately after
distillation, or aged less than two months in oak barrels.
Young (“joven”), white tequila blended with rested or aged
tequilas, and often with caramel coloring, sugar-based syrup,
glycerin, and/or oak extract added. Rested (“reposado”),
tequila aged a minimum of two months, but less than a year
in oak barrels. Aged (“añejo), tequila aged a minimum of
one year, but less than 3 years in oak barrels. Ultra aged
(“ultra añejo”), tequila aged a minimum of three years in oak
barrels [5].

quality or the productivity of Tequila (Table 1). Accordingly,
some patents have been conceded to increase the rested taste
by the addition of ethyl acetate to the raw beverage prior to
the aging process [8] or by adding an extract of oak to
produce a beverage having the same taste of a mature oak
aged alcoholic beverage in less time [9]. Tequila production
efficiency has also been optimized by the use of a treatment
of stillage generated by the tequila industry during
distillation and mashing process [10].
Second in importance as a distilled agave beverage is the
Mezcal. This is a liquour with a particular taste and specific
organoleptic properties [11]. In recent years, Mezcal market
has increased considerably, and its consumption has been
promoted since 1994 by an origin denomination law.
Several patents have been submitted to improve the

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186 Recent Patents on Biotechnology 2009, Vol. 3, No. 3 Narváez-Zapata and Sánchez-Teyer
Table 1. Main Patents Development on Agaves as a Raw Material
Authors Patent No. Main Achievement
Agave as a source of spirit beverages
Zimlich III. and Joseph A. US6132788
Describes a method to accelerate tequila maturation. This consisted in adding a food grade
solvent to accelerate this process.
Herrera Orendain, E. and
Rodríguez Flores, V. M.
US20070051612
It is a method for the treatment of stillage generated by the tequila industry during distillation
and mashing, which are intended to eliminate any contaminants contained in the stillage for the
purpose of water recovery by water vapor
Gross II, R. F., Delmore, J. P.
and Buske, W. E.
US6869630
Describes a process for producing an aged beverage, in which a partially aged beverage is
processed in a closed system with controlled heat and oxygen levels, and in contact with a
beverage aging wood product.
Goodwin, J. E., Del Rosal, A. E.,
Henríquez, R., García, G. J. and
López, S. C.
US20060159812
It is a method for making tequila by distilling a first portion of an alcoholic mixture and by
distilling a second portion of the alcoholic mixture to make a first blend.
Soltero Jimenez, F. J. US20090123600
Consisted in the production of beer-type alcoholic drink, which is based on plants belonging to
the genus Agave. This method uses sugars that are obtained for the most parts from Agave plants.
Black, K. J. and Wolpert, K. A. US20060121173
Describes a pre-made, alcohol-containing Margarita cocktail mix having improved taste, quality
and consistency. It includes a combination of concentrated lemonade, tequila and a brandy-based
orange flavored liqueur.
West, J. P. and Toreki III, W. US20030021869
Consisted in a directly ingestible capsules containing ethanol to allow to have the physiological
effects of tequila ingestion.
Agave as a source of agave fructans
Roman, S. B., Kehoe, G. S. and
Deis, R. C.
US20080299258
A natural prebiotic syrup concentrate with levels of inulin greater than 30% by weight. This can
initially be obtained from crude Agave syrups, which contain fiber as inulin but its sweetness is
relatively low. A second process uses blue agave pulp as raw material.
Silver, B. S. US20030207003 Describes a method to obtain a sweetener containing fractions of inulin from agave sap.
Frippiat, A., Van Loo, J. and
Smits, G.
US20030068429
Consisted in a method to obtain a sweetener containing fractions of inulin with improved
nutritional properties by a particular mixture of fermentable fructans components.
Meuser, F., Bauer, I., Hellwege,
E. and Pilling, J.
US20090099129
Describes a method to produce a long-chain inulin and its use in foodstuffs and cosmetic
preparations.
Wada, T. and Ohguchi, M. US20040241810
This patent describes a method to produce inulin obtained from different plant sources by
bringing inulin synthase into contact with sucrose.
Silver, B. S. US6419978
Novel fractions of inulin are disclosed which have improved water solubility and/or water
miscibility at ambient temperatures. These fractions are extracted from plant materials
containing inulin. The process includes extracting inulin with water at lower temperatures which
causes precipitation of polysaccharides and allow separate the inulin from other components.
Agave as a source of natural fibers
Beauboeuf, S. US6881257
A machinable light weight sisal-based concrete structural building material. The material
includes short sisal fibers, a cement and perlite to form a solid mixture. The produced structural
building material can be machined, screwed, cut, and nailed.
Tomka, I. US5663216
This patent describes a substantially biologically degradable polymer reinforced by additives
such as natural fibers, in particular, sisal or ramie fibers.
Spehner, J. L. US5232779
This invention describes the reinforcing of plant fibers, which the wood components have been
removed.
Tang, E. O. and Chow, D. C. US20060222719
Articles of manufacture are produced from a composition comprising agave plant residue and a
thermosetting polymer resin.

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Agaves as a Raw Material, Recent Technologies and Applications Recent Patents on Biotechnology 2009, Vol. 3, No. 3 187
(Table 1) Contd….

Authors Patent No. Main Achievement
Agave as a source of saponins
Dibb, Douglas N. and Barbour,
John B.
US3895999
A process for concentrating and recovering water soluble glycosides from agave plant juices by
foaming the solution, collecting the foam as a concentrated-in-glycoside product.
Beauvoir, M. G. US3981867
An improved process for obtaining sapogenins, mainly hecogenin, from the juice of sisal leaves
by acid hydrolysis at elevated temperature and pressure.
Mcneff, L. C. and Mcneff, C. V. US20080274211
This invention describes a method for controlling microorganism populations in the digestive
system of an animal. The invention is a composition including a saponin isolated form agave
juices and an anti-microbial agent.
Xia, Z., Hu, Y., Rubin, I.,
Brostoff, J., Whittle, B., Wang,
W. and Gunning, P.
US20020193317
A specific formulations including saponin isolated form agave for the treatment of cognitive
dysfunction.
Xia, Z., Rubin, I., Whittle, B.,
Gunning, P., Hu, Y., Brostoff, J.
and Wang, W.
US20040081709
The present invention discloses compositions based on certain furostanol saponins and
sapogenins isolated from agaves that reduce sebum production. These compounds are useful for
the reduction of excess sebum associated with dermatological disorders such as acne, dandruff,
and body malodor
Uribe, J. G., Saldivar, S. S. and
Ozuna, A. V.
US20090124685
The present invention comprises an agave syrup that contained flavonoids, polycosanols and
sapogenins, which provide anticancerigen and antioxidant properties.

Alcohol and high fructose syrup production in Agaves
Brown, R. US20080248176
A method of producing a sugar free chocolate composition comprising reduced moisture of
agave syrup and a pretreated cacao liquor.
Dince, N. US20090029010
An organic beverage comprised of rice syrup, agave nectar, fruit juice and electrolytes. The
beverage is useful for rapid hydration and replenishment of lost carbohydrates and electrolytes
after exercise, physical exertion, or exposure to heat.
Goldman, F. US20070224323
A sugar replacement includes a mixture of agave inulin and agave fructose. The sugar
replacement has reduced calories and glycemic index compared to sugar. This is particularly
useful when the sugar replacement is being used in baking recipes, baked goods and caramels.

According to the declaration of protection, Mezcal can be
made from several Agave species, so Mexican producers
make use of the available resources in their regions. A.
angustifolia from the Mexican state of Oaxaca is probably
the most well known raw material for Mezcal, given the
popularity of this drink in that state; where A. karwinskii is
also employed. A. salmiana is widely used in San Luis
Potosí and Zacatecas states and so is A. cupreata in Guerrero
state [11]. Another commonly used agave is A. duranguensis
in Durango State. Other species like A. potatorum have been
exploited to make the spirit but in smaller proportions and
within specific regions [12]. Mezcal production begins with
the harvesting of the mature heads of agave (8-12 years),
which are also known as “piñas”. Plants are castrated 1-2
years before by removing the tender flower stalk when it
starts to grow, allowing the piñas to fatten and ripe rapidly.
They are then commonly baked in rock-lined pits in the
ground; next, they are crushed to extract the juice, which is
then left to ferment and finally distilled Fig. (1). The
Mexican Official Standarization of Mezcal [13] considers
two types: 100% agave Mezcal, which comes from fermen-
ting and then distilling just the agave juice with some water,
and blended Mezcal, where other types of sugars (up to
20%) have been added to the agave must.

related to Mezcal composition [14, 15] and even fewer to its
raw material, the Agave [16, 17], probably because of the
attention that its cousin drink, the tequila, has received in
terms of research. There are no patents specifically focused
on Mezcal. However, several patents have been development
to produce different kinds of alcoholic beverages using
different Agaves genus as a raw material, as [18] that
comprise the distilling of two different portions of an
alcoholic mixture and admixing a portion of the first and
second distillates to make a first blend. The first blend may
optionally be aged, proof-adjusted, sparged with gas, and/or
filtered to provide an alcoholic beverage, being in one
embodiment refered as tequila. More recently, a method to
produce an Agave-based beer-type alcoholic drink was
patented [19]. This drink is based on sugars obtained of
different parts from Agave plants and that is fermented using
traditional methodology. Other patents considered modifi-
cations on Agave-based beverages, as the one presented to
provide a pre-made, ready to drink alcoholic margarita
beverage mix [20]. Also, there are patents focused on
development of directly ingestible capsules containing
sufficient quantities of ethanol (like tequila) to allow the
Scientific research have been focus only to studies

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188 Recent Patents on Biotechnology 2009, Vol. 3, No. 3 Narváez-Zapata and Sánchez-Teyer
consumer to have the physiological effects of such ingestion
[21].

lic beverage produced from the sap known as aguamiel,
which is extracted from several species of maguey (A.
americana, A. atrovirens, A. ferox, A. mapisaga, A.
salmiana) [22]. This beverage is currently produced and
consumed mainly in the central states of Mexico. For its
production, freshly collected aguamiel is transported into
large barrels where fermentation takes place. It has been
proposed that the fermentation process starts in the maguey,
where naturally occurring microorganisms present in the
aguamiel ferment part of the available carbohydrates.
However, the process is accelerated by the addition of the
seed (a portion of previously produced pulque). Fermen-
tation occurs overnight for at least 8 h. Classes of Pulque,
fresh or mature are determined by the grade of fermentation
and/or viscosity. The final product is placed in wood barrels.
Polysaccharides involved on the Pulque production have not
been patented yet under US patent office and constitute news
and promissory biomolecules
applications.
Pulque is another traditional Mexican fermented alcoho-
with biotechnological
AGAVE AS A SOURCE OF FRUCTANS

high content of fructans that are oligomers composed mainly
In Agave genus, the heads (piñas) of these plants poses a
of fructose units attached to a sucrose molecule, being easily
degradable by thermal or enzymatic treatments. Some of
these fructans like inulin could be converted into free sugars,
mainly fructose [23], for their subsequent fermentation.
Fructans like inuline are widely distributed in the natural
world, and it is known to be present in a colloidal form in the
tubers of Asteraceae and Agavaceae plants such as Hene-
quen (A. fourcroydes), tequila plant (A. tequilana), dahlias,
Jerusalem artichokes, wild chrysanthemums and chicory
roots [24].
Many patents have been developed to use fructans from
Agave as a raw material for many purposes. In this revision
we only considered some representative examples Table 1.
The isolation procedure of natural sweetener compounds
present in the sap of these plants has been patented as source
of natural probiotic with high levels of natural fiber similar
to inulin [25]. Similar patents have been conducted to obtain
a sweetener containing fractions of inulin from this agave
sap [26] or with improved nutritional properties by a
particular mixture of both easily and hardly fermentable
fructans components [27]. In addition, several extraction,
synthesis and improvement methods related with inulins
have been reported. In this way, it have been patented a
method to obtain a long-chain fructans [28], and a method to
produce inulin by bringing inulin synthase into contact with
sucrose [29] and a method to extract novel inulin fractions
















Fig. (1). Traditional process to obtain Mezcal from Agave plants in Tamaulipas, Mexico. A) Cores or “piñas” from different Agave species.
B) The “piñas” are baked in a pit oven. C) The “piñas” juices are crushed in an artisanal grinder or “trapiche”. D) fibers are dumped into
plastic or wooden vats to enhance the fermentation. E) Agave must obtained is distilled in a copper still.

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Agaves as a Raw Material, Recent Technologies and Applications Recent Patents on Biotechnology 2009, Vol. 3, No. 3 189
with a improved water solubility and/or water miscibility at
ambient temperatures [30].

high temperature, low pH (4.5), time, and humidity are
highly favorable for formation of Maillard compounds [31].
These are involved in the flavor (caramel-like) characteristic
of this brewage; however there are not patents proposing to
optimize the flavor formation processes from the heated
aqueous mixtures of amino acids and reducing sugars.
Finally, the cooking conditions of the agave cores such as
AGAVE AS A SOURCE OF NATURAL FIBERS

forcement materials in recent years [32]. The more widely
used Agave fibers are the sisal and the henequen, which are
obtained from A. sisalana and A. fourcroydes Fig. (2),
respectively. Both can be use for machinable light weight
sisal-based concrete structural building materials [33].
Advantages of natural fibers over man-made fibers include
low density, low cost, recyclability and biodegradability.
These advantages make natural fibers potential replacement
for glass fibers in composite materials [34].
Natural fibers have been applied as composite rein-

composites have been recently patented [35], in particular,
Use of these natural fibers in the reinforcement of
sisal or ramie fibers are used to obtained biologically and
degradable polymers. Many other patents have been focused
on increasing the potential use of these fibers as
reinforcement for polymeric materials for the manufacture of
cheap, renewable and environmentally friendly composites
[36]. The use of these fibers is optimized by the wood
reduction using a controlled addition of air to allow carbo-
nization of the fibers to take place, Table 1.

subproducts of Agave species used on alcoholic production.
For example, the leaves of A. tequilana, are common
discarded after the piña is obtained, but these can be used to
produce good quality fiber to mix with a thermosetting
polymer resin to manufacture several items like home
furnishing products, and kitchen-wares (including plates,
cups, saucers, bowls, and other dishes, vases, and storage
containers) as well as commercial and industrial articles are
also included, such as building blocks, roof and floor tiles,
ceiling and wall panels, cabinet doors, window and door
frames, counter tops for structural and decorative uses [37].
In addition, some shredded Agave fibrous waste also could
be a valuable source of paper-making fibers [38], but no
patents are available to use pulping the blue agave waste.
Currently, many patents describe the utilization of

















Fig. (2). Process to obtain natural fibers from henequen. A) Plants of Agave fourcoydes. B) Leaves collected. C) Decortication process and D
and E) shows different ways to pack the natural fiber from henequen.