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                                 INDUSTRY PROFILE #17
                                    GLUCOSE FROM
                                   CASSAVA STARCH
                                     Prepared By
                                   Peter K. Carrell
                                     Reviewed By
                                     Robert Batey
                                    Arnold Krochmal
                                      Published By
             1600 Wilson Boulevard, Suite 500, Arlington, Virginia 22209 USA
                     Telephone:  (703) 276-1800, Fax:  (703) 243-1865
                         Telex:  440192 VITAUI, Cable:  VITAINC
                  Internet:, Bitnet:   vita@gmuvax
                          Glucose from Cassava Starch
                                ISBN:   0-86619-311-1
                    [C] 1990, Volunteers in Technical Assistance
                               INDUSTRY PROFILES
This Industry Profile is one of a series briefly describing small or medium-sized industries.  The
Profiles provide basic information for starting manufacturing plants in developing nations.
Specifically, they provide general plant descriptions, financial, and technical factors for their
operation, and sources of information and expertise.   The series is intended to be useful in
determining whether the industries described warrant further inquiry either to rule out or to
decide upon investment.  The underlying assumption of these Profiles is that the individual
making use of them already has some knowledge and experience in industrial development.
Dollar values are listed only for machinery and equipment costs, and are primarily based on
equipment in the United States.   The price does not include shipping costs or import-export taxes,
which must be considered and will vary greatly from country to country.  No other investment
costs are included (such as land value, building rental, labor, etc.) as those prices also vary.
These items are mentioned to provide the investor with a general checklist of considerations for
setting up a business.
These profiles should not be substituted for feasibility studies.  Before an investment is made in
a plant, a feasibility study should be conducted.   This may require skilled economic and
engineering expertise.  The following illustrates the range of questions to which answers must
be obtained:
        *   What is the extent of the present demand for the product, and how is it now being
        *   Will the estimated price and quality of the product make it competitive?
        *   What is the marketing and distribution plan and to whom will the product be
        *   How will the plant be financed?
        *   Has a realistic time schedule for construction, equipment, delivery, obtaining
           materials and supplies, training of personnel, and the start-up time for the plant
           been developed?
        *   How are needed materials and supplies to be procured and machinery and
           equipment to be maintained and repaired?
        *   Are trained personnel available?
        *   Do adequate transportation, storage, power, communication, fuel, water, and
           other facilities exist?
        *   What management controls for design, production, quality control, and other
           factors have been included?
        *   Will the industry complement or interfere with development plans for the area?
        *   What social, cultural, environmental, and technological considerations must be
           addressed regarding manufacture and use of this product?
Fully documented information responding to these and many other questions should be
determined before proceeding with implementation of an industrial project.
                            Equipment Suppliers, Engineering Companies
The services of professional engineers are desirable in the design of industrial plants even though
the proposed plant may be small.   A correct design is one that provides the greatest economy in
the investment of funds and establishes the basis of operation that will be most profitable in the
beginning and will also be capable of expansion without expensive alteration.
Professional engineers who specialize in industrial design can be found be referring to the
published cards in various engineering magazines.   They may also be reached through their
national organizations.
Manufacturers of industrial equipment employ engineers familiar with the design and installation
of their specialized products.   These manufacturers are usually willing to give prospective
customers the benefit of technical advice by those engineers in determining the suitability of their
equipment in any proposed project.
Volunteers in Technical Assistance (VITA) is a private, non-profit, volunteer organization
engaged in international development.   Through its varied activities and services, VITA fosters
self-sufficiency by promoting increased economic productivity.  Supported by a volunteer roster
of over 5,000 experts in a wide variety of fields, VITA is able to provide high quality technical
information to requesters.  This information is increasingly conveyed through low-cost advanced
communication technologies, including terrestrial packet radio and low-earth-orbiting satellite.
VITA also implements both long- and short-term projects to promote enterprise development and
transfer technology.
Prepared By:  Peter K. Carrell
Reviewed By:  Robert W. Batey
The Product
The product is clear, colorless, glucose syrup, extracted from
dried cassava starch or cassava chips.   It is sold in drums or
tank wagons.
Glucose, also called dextrose, was first manufactured in France
early in the 19th century as a sweetener to replace sucrose
(table sugar) which had become scarce in wartime.   The variety of
its uses has since grown enormously.   Today, glucose is valued in
almost all industrial countries for its unique properties.  In
candies (sweets) and preserves it provides "body" (desired density
and flow characteristics) and controls crystallization.   In
canning, it provides body to the syrup without too much sweetness.
The Facility
A small plant can operate 250 days a year on a three-shift continuous
basis and produce about 2,500 tons of glucose syrup.   The
degree of conversion of the starch to glucose depends on customer
needs.  The plant supplies a small market and can be expanded, if
market conditions allow, to take advantage of economies of scale.
The plant should be accessible by good roads and should be near a
good supply of cooking water.   Access to a municipal sewer system
is also recommended.  Disposal of spent carbon and fiber tailings
from the starch screen are the major solid-waste problems.  Additional
environmental issues concern disposal of effluent from
housekeeping water and gases from the boiler flue and the convertor.
However, the wastes pose very little health hazard when
added to the environment.
The process is relatively simple and its principles are widely
understood.  The market demand is stable at levels depending on
local economic development.
Economic Outlook
Profitability depends on market factors, which, in turn, are
heavily influenced by the agricultural and trade policies of the
country.  Transport costs are not usually a major factor.
Manufacturing Equipment Flexibility
The same equipment can be used to produce a crude, solid form of
dextrose ("cast sugar") by acquiring aluminum pans in which the
evaporator product is allowed to crystallize.   After grinding,
this product is suitable as a reducing agent for tanning.  Making
cast sugar requires more acid to be added to the convertor supply
and slowing the rate of starch breakdown.
Knowledge Base
A chemist experienced in the food industry, particularly related
to sweets, preserves, and canning, is needed to explain the uses
of this product to potential customers.   A chemical engineer is
needed to perform or supervise analytical process control as well
as oversee mechanical operations.   It is strongly recommended that
a professional engineer with experience in the production of
glucose from starch be retained, at least when the plant is in
the planning stage.
Quality Control
The product meets established standards.   Syrup has a reducing-sugar
content equivalent to 30% to 40% glucose by dry weight ("dextrose
equivalent [DE]" = 30 to 40), and contains 80% to 82%
dissolved materials by weight.   Cast sugar requires a DE of 90.
Quality is assured by having the right laboratory instruments and
the plant personnel to use them correctly.   For the small plant,
amounts of chemicals are measured by volume or weight.   For larger
production, bags or barrels of some materials may be counted.
Acidity of the convertor supply is checked by titration.  Acid
addition and product dry substance are monitored hourly.  The
product is neutralized by adding sodium carbonate solution and
the end-point is checked with a pH meter.   The needed amount of
activated carbon is weighed according to the volume of the treatment
The concentration of dry substance is measured with a torsion
tube density controller.  Batch quality testing involves determining
reducing sugars (DE) by copper reduction, dry substance by
refractometry, color by spectrophotometry, and taste, appearance,
and odor by direct inspection.
Constraints and Limitations
Cassava is most likely to be grown only in moderate or tropical
climates.  Economical motor transport is limited to about 400 km.
If long-distance rail transport lowers the temperature to 5
degrees C or less, the tank car may need to be reheated to speed
unloading; this, in turn, can lead to unacceptable color changes.
Glucose syrup in used for hard candies and preserves, and for
making medicinal syrups, canning syrups, and table syrups.  It can
be used in manufacturing table syrups to adjust their viscosity
or consistency.  There are now better products for supplemental
addition to milk for infant feeding, but glucose syrup remains an
inexpensive substitute.
The raw material is dried cassava flour or chips.   Cassava is
grown in Africa, Central and South America (especially Brazil),
India, and Indonesia, mostly for use as a boiled vegetable.
Malaysia has a cassava-processing plant.   Manufacturing chemicals,
all common in trade, are hydrochloric acid, powdered activated
carbon, and sodium carbonate (soda ash).
Sales Channels and Methods
Sales are by direct contact with those manufacturers who are
prospective users.  Some of then may already use syrups prepared
from other sources.  Good technical service is required to adapt
the users' present formulation to the new product.   Once a use
pattern has been established, brokers may help to sell the product
in drum lots.  Sales to individuals are promoted by mass
advertising and the usual channels for food specialties.
Geographic Extent of Market
The plant should be located where cassava is grown or is readily
available at low cost.  If the water content of the cassava chips
significantly increases their shipping weight, it is best that
the plant be located near the source of the raw material.   The
product is stable and is readily transported in bulk, as well as
in drums and bottles.  High bulk-transport costs can limit the
size of the market area, The 400-km limit on motor transport can
also control the size of the market area.
Glucose syrup is well known, and competitive syrups are available
worldwide.  Syrups are manufactured from various materials in such
tropical and semitropical countries as Australia, Brazil, colombia,
Guatemala, Kenya, Mexico, Morocco, New Zealand, Pakistan,
and Venezuela.  In most of these, maize is the raw material.
Some broken rice is processed in Pakistan.   Some wheat is used in
Australia and New Zealand.
Market Capacity
As a guideline, consider that U.S. annual usage of glucose syrups
amounts to 9 kg per capita, of which 60% replaces sucrose in the
canning of foods.  At half this per-capita consumption, the plant
described here would supply a population of 1/2 to 1 million
      Requirements                         Annual Output:
                                            2,500 tons
Infrastructure, Utilities                     Small Plant
    Land                                      1500 sq m
    Building                                   400 sq m
    Power                                       30 kW
      Steam ( electric boiler)                600 kg/h
    Fuel (gas)
      cooling (from stream)                  1400 cu m/d
      boiler feed water                        14 cu m
      process, use condensate
        from evaporated heater and:             6 cu m
Major Equipment & Machinery                   Small Plant
    Tools & Machinery
    converter tank
    neutralization vat
    lift truck                                   2
    rotary leaf filter
    Support equipment & parts
    Chemical lab instruments
    Production tools & equipment
    transportation equipment
    furniture & fixtures
Materials & Supplies                          Small Plant
    Raw Materials
    cassava starch                           1870 tons
    hydrochloric acid                           8 tons
    sodium carbonate                         2750 tons
    lubricants & hand tools
    cutting tools & abrasives
    maintenance & spare parts
    office supplies
    Packaging; for example:
       Drums, 20 and 200 1
       Bottles, 500 ml
Labor                                        Small Plant
    Skilled                                     3
    Semiskilled                                 6
    Unskilled                                   6
    general mechanic                           1
    supervisor (grad. foods                    1
    technician/industrial chemist)
    sales representative                       1

06p06y.gif (600x600)

Explanation of Diagram
Workflow begins with receipt of dried cassava starch or chips, if chips, a mill and dust collector
should be added.  The raw material is dumped into the slurry tanks with water to make a slurry of
30 percent dry substance.  It is screened to remove the fibers and then pumped to a convertor supply
lank.  The chemical breakdown of starch to sugar takes place in the presence of weak acid.   After the
breakdown has proceeded to the desired stage, the acid is neutralized with soda ash (sodium carbonate).
Impurities are then removed with activated charcoal in filter presses and the product is concentrated by
evaporation as diagrammed.
The tanks and pipes are made of stainless steel and other materials in standard use for food processing.
Filter presses can be made of wood or polypropylene.
Unless otherwise stated, these addresses are in the United
Technical Manuals & Textbooks
Grace, M. R. (ed.), Cassava Processing, rev. ed.   Plant production
and protection papers, No.  3.  Rome (Italy):   Food and Agriculture
Organization of the United Nations, 1977.
Equipment Suppliers
Anhydro Division of APV Crepaco, Inc., 120 John S. Pietsch
Square, Attleboro Falls, Massachusetts 02763.   Plate evaporators,
heat exchanges.
Chemineer, Inc., P.O. Box 1123, Dayton, Ohio 45401.   Agitators.
Dedert Corp., 20000 Governors Drive, Olympia Fields, Illinois
60461.  Falling film evaporators.
Illinois Water Treatment Co., 4669 Shepherd Trail, Rockford,
Illinois 61105.  Ion exchange, chromatographic enrichment.
Mitsubishi Chemical Industries, Ltd., 5-2 Marunouchi 2-Chome,
Chiyoda-ku, Tokyo 100; P.0 Box 245, Tokyo Central, Japan.  Ion
exchange, chromatographic enrichment.
Mixing Equipment Co., Inc., 138 Mt. Read Blvd., Rochester, New
York 14603.  Agitators.
Sparkler Filters, Inc., Box 19, Conroe, Texas 77305.   Safety
filters, leaf filters.
U.S. Filters Corporation, 12442 E. Putman St., Whittier, California
90602.  Rotating leaf filters.
Financing and Engineering Companies
A.E. Staley Manufacturing Co., 2200 East Eldorado St. Decatur,
Illinois 62525.
Cargill, Inc., P.O. Box 9300, Minneapolis, Minnesota 55440
CPC International, Inc., International Plaza, P.O. Box 8000,
Englewood Cliffs, New Jersey 07632.   (This company has the widest
Professional Services:
Intensa, S.A., Rio Panuco 82, Col. Cuauhtemoc, Mexico, D.F.,
Karl Kro/yer Genbrog, A/S, Dronningens Tvaergade 16, DK-1302
Copenhagen K, Denmark.
Mitsubishi Chemical Industries, Ltd., 5-2 Marunouchi 2-chome,
Chiyoda-ku, Tokyo 100; P.0 Box 245, Tokyo Central, Japan.
Suomen Sokari Oy (Finnish Sugar Company), Kyllikenportti 2,
SF-00240 Helsinki, Finland.
VITA Resources
VITA has a number of documents on file dealing with industrial
processes.  VITA also provides a variety of services to help set
up processing plants, including locating used equipment, brokering,
etc.  Fees depend on service rendered.