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Implementation of hazard analysis critical control point (HACCP) to a production line of beet sugar, molasses and pulp: A case study



White sugar, molasses and pulp constitute three products which are very important for human health. Sugar is either directly consumed or is used as main component for confectionery purposes. Molasses and pulp are most frequently used as animal feeds and eventually find their way back to humans when the latter consume meat. Therefore, it is of great importance to ensure the standard quality and safe production of sugar and its co-products. Implementation of Hazard Analysis Critical Control Point (HACCP) constitutes a crucial step in the latter direction. Identification of critical control points made possible the control of all parameters which could eventually deteriorate the final product. Application of HACCP system shows that this production line can be adequately controlled especially when HACCP is implemented within the frame of a quality control system as ISO 9001/2.
Charalambos Z. Kotzamanidis1, Ioannis S. Arvanitoyannis2*, George N. Skaracis1and
Dimitrios Ch. Hadjiantoniou3
1 Hellenic Sugar Industry S.A.
Agricultural Research Center
Laboratory of Industrial Microbiology
57400 Thessaloniki, Hellas.
2Laboratory of Food Chemistry & Biochemistry
Department of Food Science & Technology
Faculty of Agriculture BOX 256
Aristotle University of Thessaloniki
54006 Thessaloniki, Hellas.
3Technical consultant
Anixeos 13
55236 Thessaloniki, Hellas.
* to whom all correspondence should be addressed:
Ioannis S. Arvanitoyannis (Dr., Ph.D.)
Ass. Professor
Laboratory of Food Chemistry & Biochemistry
Department of Food Science & Technology
Faculty of Agriculture BOX 256
Aristotle University of Thessaloniki
54006 Thessaloniki, Hellas.
Tel: +30 31 99 87 88
Fax: +30 31 99 87 89
White sugar, molasses and pulp constitute three products which are very important for
human health. Sugar is either directly consumed or is used as main component for
confectionery purposes. Molasses and pulp are most frequently used as animal feeds and
eventually find their way back to humans when the latter consume meat. Therefore, it is of
great importance to ensure the standard quality and safe production of sugar and its co-
products. Implementation of Hazard Analysis Critical Control Point (HACCP) constitutes a
crucial step in the latter direction. Identification of critical control points made possible the
control of all parameters which could eventually deteriorate the final product. Application of
HACCP system shows that this production line can be adequately controlled especially when
HACCP is implemented within the frame of a quality control system as ISO 9001/2.
Sugar, molasses, pulp, HACCP, hazard, critical control point.
The food industry has traditionally ensured the quality of its products by employing
inspection and test methods, managed under the banners of quality assurance and quality
control. The evolution of food industry and the explosion of food poisoning outbreaks made
apparent the need for improved and more exhaustive controls over quality and safety (Early,
The needs for a systematic approach to the production of foods that meet the criteria of
quality, safety and wholesomeness were addressed by the development of ISO 9000 series
and HACCP system. The concept of the HACCP system was first introduced in the United
States in 1959 by the Pillsbury Corporation with the participation of NASA and the US Army
Natick Laboratories. The main stimulus for devising the HACCP system was the development
of a preventive system for the production of foods with high degree of safety, extremely
crucial for a space mission (Pierson & Corlett, 1992).
Since then, the development of HACCP was a result of intense international activity,
debate and cooperation. The proper use of HACCP as a powerful management system that
functions in conjunction with other modern quality assurance systems such as the ISO 9OOO
series, has regularly been evaluated by international and governmental regulatory bodies and
proposed as the most cost effective and secure means of assuring the safe production of foods
(Baird - Parker, 1992).
According to a recently published NACMCF guide, HACCP is defined as “a
management system in which food safety is addressed through the analysis and control of
biological, chemical, and physical hazards from a material production, procurement and
handling, to manufacturing, distribution and consumption of the finished product
(NACMCF, 1997). The goals of the HACCP system include the identification of hazards
associated with production, manufacture and distribution in a comprehensive and systematic
way as well as the designation of means to eliminate or control them at an acceptable level, so
that production of safe foods is ensured (Baird - Parker, 1992).
For a long time, food industry had adopted the classical approaches to food safety such
as Good Manufacturing Practices (GMPs), which include hygienic practices , cleaning and
disinfection regimes along with end-product testing (Harrigan & Park, 1991). In contrast, the
HACCP system is designed in a preventive way aiming at assuring the control and prevention
of all potential hazards throughout the food production steps (Jay, 1992).
Although the development of HACCP plans varies and in many cases is considered as
product and process specific due to unique conditions within each food factory, the NACMCF
and United States Department of Agriculture (USDA) visualise HACCP as a systematic
approach to food safety consisting of several well-defined steps (Jay, 1992; USDA, 1997;
NACMCF, 1997). The main steps of the development of the HACCP plan are shown in
Figure 1.
NACMCF guidelines suggest that the association of a company with HACCP is
established through HACCP plan writing that focuses on five preparatory steps and seven
principles. The five preliminary steps in developing a HACCP plan are:
1. Formation of the HACCP team.
A multidisciplinary team should be assembled in order to supply the specific
knowledge required for the particular product. Assistance from external experts (third
parties, advisors) should be obtained, whenever specialised knowledge is required.
2. Product description.
A complete description of the product by providing information about the ingredients,
processing methods, retail, packaging and storage conditions should aim at identifying
any possible hazards.
3. Determination of product use.
The intended consumers (i.e. infants, patients, etc.) and the intended use of the product
should be clearly described.
4. Construction of correct flow diagram.
A correct flow diagram that identifies all the steps involved in the process should be
drawn. The flow diagram may also include steps prior to and after the processing that
take place in the establishment.
5. Verification of the process flow diagram.
The confirmation of the flow diagram that outlines the processing operation should be
performed by an on-site review. If judged necessary, modifications should be made and
The completion of the five preliminary steps is followed by the application of seven
principles, universally accepted by government agencies, trade associations and the food
industry around the globe.
The principles of the HACCP plan are:
1. Hazard analysis
This principle is focused on the identification of steps in the process, where hazards of
potential significance might occur. Moreover, the application of the principle
anticipates the identification of appropriate control measures. A hazard is defined by
NACMCF as any biological, chemical or physical agent reasonably likely to cause an
unacceptable consumer health risk in absence of its control (NACMCF, 1997). It is
essential to consider all possible sources of potential hazards. The origins of the
potential hazards need to be analysed and related to the ingredients and raw materials,
to the process related steps, to the equipment, to the product storage and distribution,
and to the final preparation and use by the consumer (Mortimore & Wallace, 1994).
Hazard analysis is accomplished in two stages; a) hazard identification based on a
review of the origins of possible hazards, and b) hazard evaluation within the frame of
the potential significance of each hazard is assessed by considering its severity
(referring to health consequences) and its likeliness to occur (based on experience,
epidemiological data and available information in the literature). The information
obtained from the above mentioned analysis will be used for deciding whether hazards
are significant and due to be addressed in a HACCP plan. Hazard analysis is completed
by listing all significant hazards associated to each step, and all control measures that
can eliminate or control these hazards to an acceptable level.
2. Determination of Critical Control Points (CCPs)
The accomplishment of hazard analysis is also extremely informative and crucial for
determination of CCPs. According to NACMCF a CCP is defined as a step at which
control can be applied to eliminate a hazard, or to reduce it to an acceptable level.
The accurate determination and documentation of CCPs based on product safety are
essential for the development of a HACCP system capable of controlling food safety
hazards. The CCP decision tree is employed as a tool for the determination of each
CCP (Figure 2). However, it must be mentioned that the CCP decision tree does not
substitute the experts that are necessary for CCP identification.
3. Establishment of critical limits (CLs)
A critical limit is defined by NACMCF and USDA as the appropriate level of
tolerance to which a biological, chemical or physical parameter must be controlled
at a CCP, in order to prevent, eliminate or reduce to an acceptable level the
occurrence of a food safety hazard (USDA, 1997).
The establishment of CLs succeeds the identification of all components or factors
associated with CCPs. Scientifically determined CLs levels, are established for all
the identified factors and components causing an unacceptable consumer health
4. Establishment of monitoring procedures
The identification of deviations from established CLs, capable of causing consumer
health hazards, is executed through monitoring procedures. These procedures
comprise scheduled observations or measurements to assess whether a CCP is
under control (NACMCF, 1997). Monitoring, either continuously or intermittently,
aims at determining whether there is loss of control through data collection. Since
monitoring is strongly related to the success of the HACCP system, it is essential
that data collection is based on statistical analysis, calibration of monitoring
equipment and assignment of the responsibility for monitoring (NACMCF, 1997;
Pierson & Corlett, 1992).
5. Establishment of corrective actions
In case of deviations from established CLs, the information obtained from
monitoring procedures is employed for the appropriate practice of corrective
actions. Undertaking corrective actions is a response to monitoring procedures and
focuses on four fields involved with processes and products (Pierson & Corlett,
1992) :
a) adjustment of the process to maintain control
b) handling of non-compliant product
c) correction of the cause of non-compliance
d) recording of the corrective actions that have been taken
6. Establishment of verification procedures
Verification process is essential for the successful implementation of the HACCP
plan. It comprises scheduled activities that verify HACCP system, concerning its
effectiveness. Validity determination of the HACCP plan is conducted during the
development and implementation of the HACCP plan. When changes in
procedures are effected or new hazards are recognised, subsequent validations
have to be performed. It is also vital the establishment of verification procedures
that comprise extensive validations of the HACCP plan due to be performed
periodically by independent authority.
7. Establishment of record-keeping and documentation procedures
Record-keeping is an inseparable part of an effective HACCP system. All
information related to the functioning of the HACCP system provide evidence of
product safety due to the established processes and assurance of regulatory
compliance. HACCP records are also crucial for tracing the history of an
ingredient, in a process or a finished product (USDA, 1997).
The following study covers the production of white beet sugar, beet molasses and beet
pulp in a processing unit.
Flow diagram used for the application of HACCP may be either detailed or just a
simple outline of the process flow, depending on the complexity of a particular operation. In
all cases, flow diagram construction is extremely crucial because it is supposed to provide
clear descriptions of all the steps involved in the process, from raw materials to end-product.
The block type Process Flow Diagram for production of beet sugar, molasses and pulp is
shown in Figure 3.
white sugar
White beet sugar belongs to the food products that are characterised for their high
purity and rarely undergo microbial spoilage due to its low water activity (aw). Despite that,
sugar can not be considered as a problem-free raw material for processing into other foods.
New developments in the food industry and consumer requirements related to nutrition
physiology, led to the establishment of standards, governing the microbial and impurity
content of sugar (Bruijn & Bout, 1999; Mauch & Farhoudi, 1980).
Microorganisms present in sugar come from the soil and the raw plant material or are
due to the manufacturing processes. High processing temperatures, pH values and dry
substance content in sugar manufacture, prevent microbial growth. However, microorganisms
in white sugar can be found, in low numbers, due to reinfection in the sugar house (Mauch &
Farhoudi, 1980; ICMSF, 1980; Smittle et al., 1992). Microflora of white sugar consists
mainly of spores of thermophilic bacteria such as Bacillus stearothermophilus that may grow
in canned food and produce acid without gas, leading to a condition described as “flat sour”,
Clostridium thermosaccharolyticum that may produce acid in canned food and form hydrogen
swells and Clostridium nigrificans that may cause sulfide spots in canned food due to the
production of hydrogen sulfide. Furthermore, small numbers of osmotolerant yeasts
belonging to the genus Zygosacchamyces and Pichia, whose growth are not inhibited at low
water activity values (aw<0.86) can be found in white sugar. The presence of the latter
microorganisms may cause cloudiness in beverages, bursting of chocolate creams and melting
of chocolate coating. Mesophilic microorganisms (especially slime producers) occurring in
white sugar are also important in the manufacture of soft drinks due to the formation of
polysaccharides (Fiedler, 1995; Poel et al., 1998; Smittle et al., 1992; Mauch & Farhoudi,
1980; ICMSF, 1980). Taking into account the spoilage of products caused by microorganisms
comprised in sugar used as ingredient in other foods, food processors have established
specific standards (Table 1). No official standards exist for the microbial content of white
sugar within the EU. However, the sugar industry has adapted itself to the consumers requests
and internal standards between sugar factories and industrial sugar users, have been
established (Poel et al., 1998; Smittle et al., 1992; Mauch & Farhoudi, 1980). Official
methods for the microbiological analysis of white sugar have been introduced by ICUMSA
comprising membrane filtration and plate method (ICUMSA, 1994).
The great significance of white sugar in daily food consumption requires the
consideration of the presence of heavy metals, in concentrations capable of causing toxic
effects. Moreover, heavy metals such as copper, present in high levels in sugar, can cause
rapid spoilage of food products containing fats or phosphatides due to their high catalytic
activity in oxidation processes. National and international sugar standards determine
maximum levels of heavy metals. The Codex Alimentarius recommends 1mg/Kg, 2mg/Kg
and 0.5mg/Kg as the maximum permissible levels for arsenic, copper and lead, respectively.
Studies on the concentration of arsenic, lead, copper, mercury and cadmium in sugar samples,
demonstrated that all these elements are present in lower concentrations than the maximum
admissible values (Poel et al., 1998; Mauch & Farhoudi, 1980; Bruijn & Bout, 1999; Morris
et al., 1976).
Molasses, produced as the final run-off syrup in sugar manufacturing, can be sold as
raw material for the production of ethanol, yeast, citric acid, or for other biotechnological
processes. The fermentation of molasses leads to an increasing demand for agents that
promote or inhibit the growth of microorganisms used in the above mentioned processes.
Quality criteria have been established especially for molasses used in baker’s yeast
technology. These criteria include growth promoting substances such as sucrose, biotin and
fermentable sugars content along with undesirable molasses compounds harmful to yeast
production such as volatile constituents, pesticides, herbicides, heavy metals, detergents and
antifoams used as process chemicals (Hadjiantoniou, 1996, Pejin et al., 1996; Fattohi, 1994;
Cronewitz, 1996; Poel et al., 1998).
With regard to the use of molasses as livestock feeding, pesticide and herbicide
residues and heavy metal content are specified in the EU by the Council Directive 74/63/EEC
and its amendments 79/934 to 91/132/EEC (EU 1991), (Poel et al., 1998). Investigations of
molasses composition have revealed that traces of detergents and antifoaming agents can be
found. In addition, pesticide and herbicide residues and heavy metals were detected at levels
lower than the allowed limits (Table 2), (Poel et al., 1998; Pejin et al., 1996; Koster et al.,
1975; Koster et al., 1981; Malmros & Tjebbes, 1979, Schiweck, 1994).
beet pulp
Beet pulp used for livestock feeding, is subjected to strict legislation in the EU. The
European Commission has presented directives on the marketing of feedingstuffs, on the
introduction of Community methods of sampling and analysis for the official control of
feedingstuffs and on additives in feedingstuffs that may strongly affect the relevant sugar
industry co-products such as pulp and molasses (Poel et al., 1998). Regulations have also
been established for the determination of the maximum allowed limits of harmful substances
in beet pulp (Table 3).
Studies on the content of heavy metals in beet pulp have revealed that they are detected
in concentrations lower than the permitted values (Poel et al., 1998; Koster et al., 1975;
Koster et al., 1981). Beet pulp may contain herbicides and pesticides which are carried over
from the sugar beet roots to the pulp through the sugar manufacturing processes (Steyvoort et
al., 1968). It is also possible that process chemicals such as detergents and antifoam agents
are present into beet pulp (Malmros & Tjebbes, 1979). Beet pulp manufacturing process
assures the microbiological safety of the product in case proper storage conditions are
maintained preventing the growth of yeasts and molds (Poel et al., 1998).
sugarbeet growing (CCP 1)
Agricultural practices such as the use of commercial fertilisers as well as sewage
sludge produced from the treatment of domestic and industrial waste waters, constitute one of
the primary input sources of metals in agro-ecosystems raising their content in the ground.
The heavy metals of primary concern contained in commercial fertilisers and sewage sludge
are Cd, Zn, Cu, Pb, and Ni (Adriano, 1986; Alloway, 1995). These heavy metals can possibly
be carried over from the ground into the plants and finally into the products of white sugar
manufacturing process.
Herbicides, insecticides and fungicides are widely used for the control of herbs, insects
and diseases in sugarbeet crop. Their use can lead to the detection of residual traces of such
chemicals in white sugar, pulp and molasses (Poel et al., 1998; Pejin et al., 1996; Koster et al.,
1975; Koster et al., 1981; Malmros & Tjebbes, 1979, Schiweck, 1994; Steinle, 1977). In
addition, according to the type used, pesticides can contribute to the increase of heavy metal
soil content.
The heavy metal and pesticide residue contents of white sugar, pulp and molasses
depend to a large extent on the quality of the processed sugarbeets. The appropriate use of
fertilisers and pesticides according to supplier instructions is essential for assuring that raw
material will not be seriously contaminated. Following the steps of the CCP decision tree, the
control of the fertilisers and pesticides used, is crucial for the elimination of heavy metal
presence in sugar.
sugar extraction (CCP 2)
The microorganisms entering the extraction system mainly originate from the beet
fields and vary proportionally to the microbial population of the soil in which the sugarbeets
are grown (Samaraweera & Berg, 1991; ICMSF, 1980). Extraction system conditions such as
temperature, pH value, water activity and sugar content favour the microbial growth as well
as sugar losses. Microbial activity leads to the formation of reducing sugars due to sucrose
degradation and production of secondary metabolites such as organic acids and
exopolysaccharides (dextran, levan). In addition to the sugar losses caused by
microorganisms, microbial activity presents significant difficulties in the sugar manufacturing
process due to the formation of slime (levan, dextran) which clogs pipes and filters and the
production of lactic acid that induces corrosion of steel in the extractor and ancillary systems.
Microbial flora of the extraction system consists mainly of mesophiles ( Lactobacillus and
Leuconostoc spp.) and thermophiles (Bacillus stearothermophilus, B.pumilus, Clostridium
spp) (Belamri et al., 1991; Samaraweera & Berg, 1991; ICMSF, 1980; McGinnis, 1971;
Bruijn et al., 1991; Pollach et al., 1996).
For inhibiting microbial growth into the extraction system, sugar factory employs
chemical control with the use of formalin (40% aqueous solution of formaldehyde),
quaternary ammonium compounds, dithiocarbamates and sulphur dioxide. The disinfection
program in sugar industry is mainly based on the use of formaldehyde which is considered as
the most effective biocide in the prevention of sugar losses due to lactic acid producing
bacteria. However, its use has been recently associated with carcinogenic effects in workers
exposed to it (Poel et al., 1998; Pehrsson et al., 1995). The selection of biocides and their
amounts used should be based not only on their effectiveness but also on their residual
quantities found in sugar, molasses and pulp. The use of disinfectants should comply with
food regulations according to EU Directive 93/43 of 14 June 1993 which provide general
rules for disinfection in the food industry and Directives 67/548 of 27 June 1993 and 88/379
of 7 June 1988 which classify as dangerous the substances taking into account their physico-
chemical and toxicological properties (Maris, 1998). Disinfectants should be purchased from
official suppliers and should be adequately packaged and labeled providing information about
their proper manipulation thus ensuring their safe handling and use. Taking into consideration
detergent residuals traced in sugar, molasses and pulp and possible health risk associated with
the concentrations/doses of disinfectants to which human populations or environmental
compartments are or may be exposed, the sugar industry has been investigating the use of
alternative substances for disinfection (Pehrsson et al., 1995; Pollach et al., 1996; Bowler et
al., 1996).
Sugarbeets contain saponins (glycosides of hydrophobic alcohols) that enter the
extraction system thereby leading to the formation of foamy solutions. Foaming of flume
water and raw juices inhibits the circulation of liquids affecting the overall processes of sugar
production. Sugar factory employs antifoaming agents such as modified fatty acids to face the
problem caused by saponins (Poel et al., 1998). The use of antifoaming agents in excessive
amounts can lead to traces of them in molasses and pulp. Antifoaming agents should be
obtained from official suppliers which provide information according to EU Directives as is
the case with disinfectants.
Pulp pressing, drying, pelleting and storage (CCP 3)
Beet pulp consists of sugar depleted cossettes that leave the upper part of the extractor
with a very low dry substance content. In this form pulp is not economically suitable for
direct animal feeding and undergoes further treatment. Wet pulp is carried over to pulp
presses where is submitted to mechanical dewatering reaching a 30% dry substance content.
After pressing and addition of molasses in a portion of 15 to 18%, pulp is transported via
conveyors to a direct-fired, rotating drum dryer. Pulp dryer installation comprises a furnace
which, utilising crude oil as fuel, generates a gaseous atmosphere at a temperature of 600 to
900oC. Drying is an evaporation step, in which pressed pulp coming in contact with the
combustion gas is dried to a final dry substance content of approximately 90%. After drying,
pulp is pelletised by pelleting presses and is transferred to warehouses (McGinnis, 1971).
Due to the use of dried beet pulp for livestock feeding, analyses for the detection of
heavy metals and pesticide, disinfectant and antifoaming agent residues should be regularly
done. Special care should be given to the fuel used for the pulp dryer that may increase the
pulp heavy metal or nitrosamines content (Poel et al., 1998). The presence of contaminants in
beet pulp, originating from the process or the sugarbeets themselves, is regulated by Animal
Feed Legislation of the EU. Sampling procedures and methods of analysis should comply
with Analysis Directives of the EU.
Contamination of the dried pulp due to the fuel used for the pulp dryer can be
prevented by purification of the exhaust gas with the use of cyclone devices or gas washers.
Beet pulp is characterised as a substance of low risk of spoilage because of its high dry
substance content (90%). However, special storage conditions of pulp pellets are required to
prevent microbial growth and spontaneous combustion (McGinnis, 1971; Poel et al., 1998).
Pellet warehouses should be ventilated to lower air humidity as well as temperature monitors
should be installed to detect spontaneous heating of pulp, caused by chemical reactions or
microbial activity. In case of spontaneous heating the affected area should be rapidly removed
from the storage pile.
crystallisation and centrifugation (CCP 4)
Thick juice coming from the evaporation plant contains a low number of
microorganisms due to high temperature treatment. However, next process steps cause
microbial contamination of syrups and consequently sugar losses. High levels of humidity and
temperature in the sugar house as well as syrup remains that cover as thin films the walls,
floors and pipes, favour microbial growth and generate sources of contamination (Mauch &
Farhoudi, 1980). Strict measures in combination with hygienic precautions should be taken in
order to avoid microbial contamination. These measures could include air circulation, sugar
house temperature regulation when is possible, fast operation under high technologically
acceptable temperatures, general cleanliness of the production process and equipment. When
possible, storage tanks and pipes of the transport system should be covered, monitored,
cleaned and sterilised by the use of officially approved cleaning agents and disinfectants.
Special care should be taken in the use of appropriate filters, which are able to remove more
than 90% of the bacteria present in juices (Hollaus, 1997). Moreover, heating of the standard
liquor at a temperature of 90oC could destroy microorganisms which enter the crystallisation
stages (Poel et al., 1998).
The centrifugation process is considered crucial for sugar manufacture since any
downgraded sugar quality during this manufacturing stage is irreversible and no correction
stage is applicable at subsequent stages. During centrifugation the major part of microbial
population is removed together with syrup by centrifugal force. However, crystal sugar
conglomerates prevent removal of microbes due to the fact that microorganisms are trapped
into them. Formation of crystal conglomerates should be avoided by the use of appropriate
technological practices. Wash water, used during centrifugation, may become one of the
major sources of sugar microbial contamination. Therefore, filtration and sterilisation of the
wash water which comes into contact with sugar is essential (Mauch & Farhoudi, 1980).
During centrifugation, one of the major concerns should be the materials such as the
discharger and washing devices and screens which come into contact with the final product
(sugar). According to EU Directive 93/43 of 14 June 1993 on the hygiene of foodstuffs,
centrifugation equipment should be constructed of such materials that minimise any risk of
contamination because of substance migration into the sugar. Stainless steel, is usually
preferred to other materials because of its ability to maintain a high level of performance
while keeping corrosion to a minimum, for all the parts that come into contact with sugar
(Maller, 1998).
drying and cooling of sugar (CCP 5)
Serious microbiological problems arise during the drying/cooling sugar manufacturing
stage. Airborne microorganisms constitute the main source of microbial contamination since
sugar dust is a suitable carrier of mould spores (Mauch & Farhoudi, 1980; McGinnis, 1971).
The formation of moist sugar crust at the conveying devices as well as the condensed water at
the ceilings that may drop on the conveyors are the main components of sugar microbial
contamination (Hollaus, 1997). The most important action to avoid sugar contamination is the
implementation of sanitary measures in agreement with high hygienic standards. All the
premises included conveyors should be constantly monitored and cleaned by the use of
appropriate disinfectants. The enclosure of the conveyors by which sugar is transported and
the installation of air filters for dust collection are considered essential measures for reducing
the contamination risk.
The presence of foreign bodies such as metals, glasses and plaster from the walls and
ceilings should be of major concern during the drying/cooling stage of sugar manufacturing.
Techniques such as metal detection and X-ray systems, widely applied for the detection of
foreign bodies buried inside a food product, should be employed in order to assure white
sugar safety (Graves et al., 1998). As in the case of centrifugation stage, product-contact
surfaces such as conveyor’s belts, drum dryer and screens should be constructed of such
materials that minimise any risk of sugar contamination.
sugar storage (CCP 6)
White sugar is stored as sacked in storehouses and as bulk in silos. Sacked sugar is
stored in piles whose height depends on the crushing strength of the full sacks. Storehouse
into which the sacks are placed is ventilated to ensure the regulation of temperature and
relative air humidity. Long term sugar storage depends on maintenance of certain temperature
and humidity conditions that prevent sugar from becoming hard or caked or excessively wet.
High storage temperature (above 25oC) and relative humidity of the air above 60% induce
sugar crystal agglomeration (Mikus & Budicec, 1986). Additionally, the number of germs in
sugar depends on conditions of storage such as temperature, moisture and ventilation
(Hollaus, 1997).
Monitoring of temperature and relative air humidity is essential for long term storage of
sugar. The storehouses and silos should comply with high standards of hygiene to prevent
microbial contamination and sugar quality downgrading. In the storehouses where the sugar
bags are piled, the storage of other products neither in the same nor in the neighboured room,
should be allowed. For bulk sugar storage it is essential that the air used for silos conditioning
is filtered in order to prevent microbial contamination.
packaging (CCP 7)
White sugar is packaged into multi-wall paper sacks. At this stage the encountered
hazards can be of microbiological, physical and chemical origin. Microbial contamination of
sugar during packaging may originate from the packaging material (Poel et al., 1998; Hollaus,
1997; Mauch & Farhoudi, 1980) the equipment used and the personnel. Therefore, high
standards related both to food hygiene and personnel hygiene should be maintained within the
packaging area. Sugar-contact surfaces should be constantly monitored and cleaned, air filters
for dust collection should be used and sanitary measures for storerooms of the packaging
materials should be practiced. Physical hazards originating from foreign materials found into
packaged sugar, are eliminated by the use of metal or X-ray detectors.
Chemical hazards most frequently originate from the packaging material. The direct
contact of sugar with packaging paper could lead to chemical contamination of sugar due to
migration of heavy metals, paraffin components, dyes and chlorinated organic compounds
(Conti & Botrè, 1997; Soderhjelm & Sipilainen, 1996). The presence of these toxicants in
foods could represent a threat to the consumers’ health. Paper sacks should be approved for
food packaging, purchased from official suppliers and adequately packaged.
transportation (CCP 8)
Sugar transportation is carried out by tanker vehicles or covered trucks. Tanker
vehicles and trucks are used for transportation of bulk and packaged sugar, respectively.
Regardless the way that sugar is dispatched to customers, vehicles should only be used for
food transportation and they should be inspected for chemical remains and for the presence of
foreign materials and condensed water which may eventually become source of microbial
contamination. During bulk transportation, tanker vehicles should be loaded through flexible
pipes that are constructed from material approved for coming in contact with foods. Special
care should be also taken of the pipe connections, so as to avoid contamination of the sugar
(Poel et al., 1998).
The hazards, critical control points (CCPs), critical limits (CLs), monitoring and
responsible personnel for sugar production are summarised in Table 4.
Although the sugar industry is considered one of safest industries in terms of occurring
incidents and outbreaks caused by its product/co-products, the implementation of HACCP
substantially improves the safety of these products. In fact, a closer inspection of critical
control points introduces the range of most crucial parameters (moisture, heavy metals,
pesticides, herbicides, extraneous materials) within the acceptable limits as prescribed by the
corresponding legislation.
Furthermore, HACCP helps to improve the hygiene both of personnel and installations
thus ensuring the prevention of cross-contamination. In general, the benefits from HACCP
implementation are substantially enhanced when HACCP is applied in the factory in
conjunction with Total Quality Management.
1. Adriano, D.C. (1986) Trace Elements in the Terrestrial Environment, Springer-Verlag,
New York.
2. Alloway, B.J. (1995) Heavy Metals in Soils. Blackie Academic & Professional, London.
3. Baird – Pairker, A.C. (1992) The Hazard Analysis Critical Control Points Concept and
Principles. Bulletin of the IDF 276, 15-19.
4. Belamri, M., Mekkaoui, A.K., Tantaoui-Elaraki, A. (1991) Saccharolytic Bacteria in
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Beet Extraction – a Model Study. Zuckerindustrie 116, 729-732.
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9. Codex Alimentarius Committee on Food Hygiene (1997) Recommended International
Code of Practice. General Principles of Food Hygiene. CAC/RCP 1-1969, Rev. 3.
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Atomic Absorption Spectroscopy Investigation. Food Control 8, 131-136.
11. Cronewitz, T. (1996) Effects of Sugar Manufacturing Technology and Processing Aid
Usage on the Properties of Molasses for Yeast Production. Zuckerindustrie 121, 401-407.
12. Early, R. (1995) Guide to Quality Management Systems for the Food Industry. Blackie
Academic & Professional, London, pp. 1-48.
13. Fattohi, N. (1994) Studies of Volatile Secondary Molasses Constituents with Inhibitory
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by GC and HPLC. Zuckerindustrie 119, 554-560.
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in Sugar as well as in Sugar-containing Raw Materials and Foods. Zuckerindustrie 120,
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17. Hadjiantoniou, D. (1996) Raffinose and betaine in the molasses during the sugar beets
campaigh in Greece. Proceedings of the 59th IIRB Congress, February 1996.
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20. ICUMSA (1994) ICUMSA Methods Book. ICUMSA Publications Dept., Norwich.
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Molasses Quality for Baker’s Yeast Production as Influenced by its Microbiological
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Figure 1 Steps of a HACCP plan (Baird, 1992).
Figure 2 The CCP Decision Tree (NACMCF, 1997).
Figure 3 Process Flow Diagram of beet sugar, molasses and pulp production line in a
Sugar factory.
11. CONTROL 10.
Figure 1 Steps of a HACCP plan (Baird, 1992).
Q 1. Does this step involve a hazard of sufficient likelihood of occurrence and
severity to warrant its control?
Not a CCP
Q 2. Does a control measure for the hazard exist at this step?
YES NO Modify the step,
process or product
Is control at this step
necessary for safety?
Q 3. Is control at this step necessary to prevent, eliminate, or reduce the risk of the
hazard to consumers?
*Proceed to next step in the process.
Figure 2 The CCP Decision Tree (NACMCF, 1997).
Table 1 Microbiological standards for white sugar of the National Soft Drink Association,
USA (Bottlers) and the National Canners Association, USA (Canners); maximum
admissible germ per 10 g sugar or maximum admissible number of positive samples or
tubes examined (Poel et al., 1998; Mauch & Farhoudi, 1980).
Bottlers Canners
Microorganisms Maximum Average
of 5 samples of 5 samples
Mesophilic bacteria 200
Molds 10
Yeasts 10
Thermophilic spores 150 125
Flat sour spores 75 50
Anaerobic gas producers 3 of 5 samples 4 of 6 tubes
Sulfide producers 2 of 5 samples 5 spores per 10 g
Table 2 Pesticide and heavy metal contents of beet molasses compared with EU
admissible limits in mg/Kg (Poel et al., 1998)
Czech beet EU maximum
Organochlorine pesticides
Aldrin + Dieldrin expressed as Dieldrin 0.0009 0.01
Camphechlor (toxaphene) -* 0.10
Chlordane, sum of cis and trans isomers -* 0.02
DDT, sum of DDT, TDE and DDE isomers -* 0.05
Endosulphan, sum of α and β isomers 0.0006 0.10
Endrin, sum of endrin, D and Keto-endrin -* 0.01
Heptachlor, sum of heptachlor and epoxide 0.0008 0.01
Hexachlorobenzene (HCB) 0.0003 0.01
Hexachlorocyclohexane (HCH), α, β and χ 0.0013 0.02, 0.01, 0.20
Heavy Metals
Mercury <0.02 0.10
Cadmium <0.02 1.00
Lead <0.10 10.00
Arsenic <0.10 4.00
*None found
Table 3 Maximum levels of undesirable substances allowed in feedingstuffs derived
from sugarbeet processing, in terms of feedingstuffs with 12% water content (Poel et
al., 1998).
Substances Straight feedingstuffs Maximum content
and feed materials in mg/Kg
Arsenic Dried pulp and partially
exhausted and dried pulp 4
Other 2
Lead All feedingstuffs from
beet processing 10
Cadmium (Cd) » 1
Fluorine (F) » 150
Mercury (Hg) » 0.10
Aflatoxin B1 » 0.05
Chlorinated hydrocarbons
Aldrin/Dieldrin » 0.01
Camphechlor » 0.10
Chlordane » 0.02
DDT » 0.05
Endosulfane » 0.10
Endrin » 0.01
Heptachlor » 0.01
Hexachlorobenzene (HCB) » 0.01
Hexachlorocyclohexane (HCH):
α isomer » 0.02
β isomer » 0.01
γ isomer » 0.20
Figure 3 Process Flow Diagram of beet sugar, molasses and pulp
production line in a sugar factory.
Table 4 Synoptic presentation of Hazards, CCPs, CLs, monitoring and responsible personnel for sugar production.
Critical Control Point Critical Limit Monitoring of CCPs
Identity of
Stage Hazard Method Frequency Recording
growing Chemical
Toxic metals and pesticide
residues present in high
Chemical analysis by Gas
Chromatography (GC)
Atomic Absorption
Spectroscopy (AAS)
Incoming material
control files
Quality Control
extraction Chemical
Sufficiently low disinfectant
and antifoam residue content
not passing to next stage
Chemical analysis by GC Every
Extraction Control
pulp pessing,
pelleting and
1) Chemical
2) Microbiologi
(presence of
1) According to EU
legislation for
feedingstuffs (Table 3)
2) According to EU
legislation for
feedingstuffs (Table 3)
1) Chemical analysis by
AAS and GC
2) Immunoassays
Co-Product Quality
1) Microbiologi
2) Chemical
1) Absence of
microorganisms in
juices, clearance of all
materials coming in
contact with sugar
2) Heavy metals in juices
1) Detection of germs
and spores
2) Chemical analysis by
sugar batch Control Files Quality Control
Drying and
of sugar
1) Microbiologi
2) Physical
(presence of
1) Absence
2) Absence
1) Analysis according to
ICUMSA methods
2) X-ray detection, metal
1) Every
2) Contin
Archives both as
hard copies and in
electronic form
Sugar storage Microbiological Presence of microorganisms
within a range agreed with
Analysis according to
ICUMSA methods
Archives both as
hard copies and in
electronic form
1) Microbiologi
2) Physical
(presence of
3) Chemical
(due to
migration to
from the
1) Presence of
microorganisms within
a range agreed with
2) Absence
3) Heavy metal contents
below the maximum
permissible levels
1) Analysis according to
ICUMSA methods
2) Absence
3) Chemical analysis by
Archives both as
hard copies and in
electronic form
1) Microbiologi
2) Physical
materials into
1) Absent of moisture into
tanker vehicles
2) Absent of foreign
materials into tanker
Visual inspection
recording on chart
... Food additives containing sulfur are usually used as fumigants, decolorizers, and preservatives. These chemicals are used as decolorizers in the sugar industry to purify syrup and remove natural color compounds obtained from sugar beet [4] and sugar cane and color compounds created during production [5]. Sulfuric anhydride, potassium bisulfite, potassium metabisulfite, sodium hydrogen sulfite, sodium bisulfite, and sodium metabisulfite as an example of sulfurous organic compounds are used as preservatives and colorants in the food industry. ...
... To better understand the reaction dynamics between BSA and sodium hydrosulfite, temperature-dependent thermodynamic parameters including enthalpy changes (ΔH • ), entropy changes (ΔS • ), and Gibbs free energy change (ΔG • ) or reaction probability using Van't Hoff equation (4) (Fig. 4) and Gibbs-Helmholtz equation (5) were estimated. (5) in this equation, T is the absolute temperature and R is the gas constant. According to the Ross and Subramania thermodynamic theory, when both ΔH • and ΔS • values of ligand-BSA interaction are greater than zero, hydrophobic interaction has occurred between the two molecules. ...
... The work [9] provides a theoretical analysis of critical control points for the production of a line of sugar, molasses and pulp. Data are provided to identify potential hazards for sugar, molasses and beet pulp, as well as critical control points, monitoring and responsible personnel for sugar beet processing. ...
Full-text available
The objects of research are the process of sugar beet processing, sugar beet, sugar and molasses. The problem of determining critical control points in sugar beet processing and safety indicators of raw materials and products of the sugar industry was solved. The results were obtained based on the risk analysis and the system of control points for sugar beet processing, five critical control points were identified according to the criteria of physical, chemical and biological contamination. It was also found that in terms of safety indicators, raw materials – sugar beet, and finished products meet the requirements of regulatory documents for microbiological indicators and heavy metal content. The safety indicators of sugar beet, white sugar, molasses and beet pulp were studied. Microbiological indicators: CGB (coliforms), pathogens and S.aureus were not found in sugar beet samples. Microbiological indicators of QMAFAnM and yeast of white sugar, molasses and pulp 1–5*102, 6–7*102, 5–8*102 and 2–3*101, 1–3*101, 1*101 CFU/cm3, respectively, are within acceptable limits. The content of toxic elements did not exceed the permissible limits. For Kazakhstan sugar factories, no studies on hazard analysis and critical control points in the sugar industry have been conducted before, so the results of the study will fill this gap. The scope and conditions for the practical use of the results obtained are the possibilities of raising the quality of finished products and improving the safety of raw materials and finished products, increasing the shelf life of by-products (molasses, beet pulp) of sugar beet production. These opportunities are based on the hazard analysis and critical control points (HACCP) in sugar beet processing
Full-text available
Many food safety incidents have occurred in the world in the past 20 years, causing major threats and harm to human life and health. Each country or region has established different food safety management systems (FSMSs) in response, to increase food safety and to reduce food safety risks. Hence, it is important to develop an FSMS service platform with convenience, consistency, effectiveness, scalability, and lightweight computing. The aim of this study is to design and propose an IOTA Tangle-based intelligent food safety service platform for bubble tea—called IF4BT—which modularizes and integrates hazard analysis and critical control point (HACCP) principles to increase data transparency. The deep learning inference engine is based on long short-term memory and Siamese networks to check and extract significant rare data of high-risk factors, exception factors, and noises, depending on daily check and audit. IF4BT can ensure the correctness of the information of food manufacturers, so as to increase food safety and to reduce food safety issues such as allergen cross-contamination, food expiration, food defense, and food fraud.
The technological developments in sugar processing during year 2001 were examined. Various developments in areas such as beet and cane transport, extraction, clarification, demineralization and decolorization, mill sanitation and energy economy were presented. Publications concerned with energy and environmental issues were described. A modernization program at the Renville beet sugar factory in the USA was also described.
Full-text available
The levels of four representative heavy metals — Cd, Cr, Pb and Hg — have been measured by atomic absorption spectroscopy (AAS) in 12 different samples of paper: 7 different kinds of food packaging paper, commonly employed in Italy (brown and white bread bags, brown and white bakery paper, white bakery bag, butcher's paper and salami paper), and 5 samples of non-food paper (two newspapers, one weekly magazine, one blue and one yellow notebook), assayed, for comparative purposes, in the same experimental conditions. The levels of heavy metals have been measured in all the samples according to two different procedures: i) after immersion in distilled water for 24 h at T = 23%; and ii) after immersion in 3% v/v acetic acid for 24 h at T = 40 °C.The results of the present investigation show that all samples of food packaging paper contain concentrations of heavy metals that are generally lower than those detected in samples of common paper. Moreover, our results show that there is a remarkable difference among the levels of heavy metals depending on the procedure of sample pretreatment. Our observation points out that the pretreatment usually indicated as ‘migration test’ (performed in 3% v/v acetic acid at T = 40 °C), being remarkably more drastic than the ‘extraction test’ (performed in distilled water at T = 23 °C), should be requested in all those cases in which a direct contact occurs between the food and the paper packaging.
The molasses produced as the final run-off in sugar manufacturing is used as feed stock to produce yeast. The composition of molasses and hence its fermentation properties are essentially determined by the nonsugars in sugar beets, but are also affected by the processes in the sugar factory. This paper discusses the question what effects changes in sugar manufacturing technology and use of processing aids have and can have. Experience at Südzucker has shown that technical developments, including the introduction of processing control techniques, have led to better process management and consequently to more careful treatment of the product. These developments, connected with increases in capacity, energy saving and emission reduction, have restricted and lowered, rather than increased, the employment of processing aids. The selection of new processing aids is subject to strict rules within the framework of the Südzucker quality management system, which the paper describes. A fermentation test, linked to a discriminating programme of analyses for chemical and physical indicators, is applied to assess the properties of molasses. This broadly conceived analytical programme, tailored to the specific requirements of molasses fermentation, forms the basis for the interpretation and classification of various molasses properties. Südzucker thereby seeks to contribute actively to ensure that molasses continues to be a reliable feedastock for the manufacture of baking yeast.
This paper deals with the microbiological and chemical composition of molasses from five sugar factories over a period of three years. In total 77 samples of molasses were analyzed for content of biotin, total nitrogen, sucrose, dry substance and number of mesophiles and Leuconostoc sp. Linear regression equations were calculated for the dependence of sucrose content from fermentable sugars content, biotin content from total nitrogen content, purity from biotin content, total nitrogen content from purity and leuconostoc from total number of mesophiles. A significant dependence was found for sucrose content from fermentable sugars content, biotin content from total nitrogen content, purity from biotin content. The equations are reliable for prediction and evaluation fo the quality of molasses for baker's yeast production.
Nutrition physiology as well as hygiene require a more detailed approach to white sugar and its impurities. In the literature, more than 20 different criteria are described which could influence, in some way or other, the quality of sugar, its processibility or its direct use in the household. The most important criteria are discussed. In granulated sugar manufactured from sugar beet, floc formation is mainly caused by saponins. The maximum permissible values of toxic heavy metals are fixed by government regulations. The content of other heavy metals found in sugar are tabulated. Visual appearance of granulated sugar, color and turbidity of solutions and their conductivity are used as general criteria for sugar quality. Quality factors are treated under various aspects. The analytical possibilities for the determination of the various quality factors are demonstrated.
Methods for the determination of mercury in dried sugar beet pulp and molasses by flameless atomic absorption procedures have been studied. Recoveries of added mercury ranged from 90 to 105%. Limits of detection of the methods range from 3 to 5 ng of mercury. Investigations into the relationship between particle size and mercury content in ground pulp samples emphasize the importance of a well-designed sample preparation procedure. Good agreement is shown between the methods and the results obtained are comparable with those obtained by neutron activation analysis. The methods were applied to samples of pulp and molasses produced at various factories in Holland, the United Kingdom and the German Federal Republic during 1973/1974 and 1974/1975. With a few exceptions, the levels of mercury found in these samples fall within the prospective EEC standard for animal feeding stuffs.
Though sugar production has a seasonal character, its consumption is actually evenly distributed over the whole year. Large quantities of sugar must therefore be stored for different time periods. It is the aim of this work to present a balanced sum of the knowledge gained in our own studies of this problem, together with data from other fields, concerning these problems.
Research has been carried out to determine whether formalin, a widespread processing aid in the sugar industry, could be replaced by hop products principially. It was found that a product called "Base-extract" exists in the hop industry, whose price, based on the effect, is able to compete with formalin. The activity of this extract is based on a high content of bacteriostatically efficient hop-β-acids. During experimental stage dosing of this pasty and water-insoluble product was a problem, which was overcome by emulsifying with sorbitol ester or in case of short pipes by direct dosing of warmed extract. Under Austrian conditions, i.e. with an acceptance of microbial acid formation in the upper part of the extraction towers to improve pulp pressing, the content of lactic acid in the raw juice could be reduced to approx. 400 mg/l by dosing of Base-extract. After juice purification nitrite-forming microorganisms, within a juice softening equipment by an ion exchanger were successfully controlled with the help of Base-extract. It was found that also in this case hop constituents were inactivated to the extent that no harmful enrichment in molasses occured.
The use of Proxitane® formulations as a biocide in the sugar industry is described. Previous trials in the United Kingdom and Finland, comparing them against formalin, in both RT drum and tower extraction systems have been successful and have been reported [1]. Further progress has been made since then with reductions in application rates and identification of process improvements. Proxitane® has also been successfully compared with systems using glutaraldehyde and dithiocarbamate in a RT5 extraction system in Belgium.
Application of currently available (instrumental) analytical techniques has made it possible to both identify and quantify most of the minor constituents of white sugar, which above certain levels might interfere with customer problems. The application of different high-performance liquid chromatography methods for the analysis of inorganic cations (ammonium, calcium, magnesium, potassium and sodium) and anions (chloride, phosphate, nitrate, nitrite, sulfate and sulfite), organic acids (citrate, malate, oxalate, acetate, formate, lactate and pyroglutamate) and metal cations (cobalt, copper, iron, nickel, manganese and zinc) in white beet sugar samples is described. The origin of these constituents will be discussed as far as known. The presence of other miscellaneous nonsucroses, such as for instance invert sugar, saponins and micro-organisms, will be mentioned briefly.
A new technique for eliminating matrix interference in the determination of lead, cadmium, and zinc in sugars by flameless atomic absorption is described. Yeast fermentation converts the sucrose to ethanol and carbon dioxide, both of which are easily volatilized. Reproducible results for these elements are obtained with this technique. Relative standard deviation for lead and cadmium was less than 10%, and for zinc less than 17%. Using this yeast fermentation technique, it was found that all three elements were present in raw and refined sugars at levels well below limits recommended by regulatory agencies.