Status of UK's Natural Mineral Waters in EU/EEA after 1 January 2021

Essentially, if exporting to EU/EEA states and Northern Ireland, an application for recognition of mineral water has to be made after 1 January 2021.

UK mineral waters would be regarded as 3rd country waters and have to be accepted by a member state. If one member state (EU and EEA) recognises the UK mineral water, all states will recognise the mineral water automatically. 

The UK mineral water must comply with the requirements of the 2009 Directive for mineral water (2009/54/EC).

Note that Northern Ireland is included solely because of the Northern Ireland Protocol. 

Applications have to be made in the language of the member state approached. Currently, Republic of Ireland and Malta cannot accept applications because of lack of administrative capability. Some countries will charge an administrative fee plus expenses (for example to visit the source).

 The requirements for TVC count at source are interpreted differently in the UK compared with the 2009 Directive. The Directive indicates maximum values of 20/ml and 5/ml at 22 deg C and 37deg C respectively, whereas the UK interpretation treats these figures as a guide only. If values are higher than these, some clarification will be required when making applications. 

Some countries (for example France) have suggested applying now to save time. Other counties will allow existing stocks in a country to be used up before applying the recognition requirements.

New Drinking Water Directive

The Directive was first published in 1998 and since then there have been three amended versions from 2003, 2009 and 2015. Over 20 years have passed since the first Directive and many things have changed since then regarding drinking water contamination. Four areas were considered as needing revision:

• The list of parameters

• The use of the risk-based approach

• Increased transparency giving consumers access to up-to-date information

• Greater insight into materials in contact with drinking water and analysis of migration

Rather than issue another amended version of the Directive, it was decided to recast a new version.

Redundant Parameters

Some parameters are no longer considered to be a problem in today’s water supplies, such as benzene, mercury and cyanide and these have been omitted from the listings.

New Parameters

Some parameters have been added, such as polyfluoroalkyl substances, which are considered as increasing pollutants (these are used widely in fire-fighting foams). Uranium has been added (occurring naturally or as a contaminant). Clearer indications of analytical methods and thresholds for migration of pipework materials into water (vinyl chloride, epichlorohydrin and acrylamides) have been established. The full list of new additions is about to be published.

Risk Analysis

Rather than analyse annually a large list of parameters, the list may be made smaller by considering the individual risks at the location of water extraction. This was first described in the 2015 amendment and briefly is as follows:

• Analytical results should be review over the previous 3 years

• If the parameter measured is consistently less than 30% of the threshold during this time, it may be  omitted

• If the parameter measured is consistently less than 60% of the threshold, the frequency of analysis may be reduced

Tables in the New Directive

There are three Tables in the new Directive, A, B and C. The latter is new and intended to provide more information for the consumer:

• Table A, microbiological parameters

• Table B, physico/chemical parameters

• Table C, indicator parameters

The indicator parameters are not considered harmful, such as colour, taste, conductivity and turbidity but are considered useful information for the consumer. Interestingly, HPCs and coliforms have been included in this table and removed from Table A.

Exemptions to the Directive

Bottled mineral waters are exempt from this Directive and considered under Directive 2009/54/EC. Spring water, on the other hand, is covered partly by the 2009 Directive and partly by the new Drinking Water Directive. The requirement from the 2009 Directive is that microbiological analyses for spring water must be the same as those for mineral water and with the same thresholds. Other aspects are covered by the new Drinking Water Directive.

At the point of bottling, mineral water, spring water and drinking water are considered as foodstuffs under Regulation 178/2002 and follow the requirements of food law.

Bottling plants that have their own private water supply (borehole, spring) and use it for bottling water for sale are exempt from the provisions of the Directive, provided they follow a HACCP plan under the relevant legislation on food.

Water Quality for POU

Water Quality – filtration, treatment and testing

Introduction

POU water dispensers use the water at point of entry into the building.  Depending on the quality of the water, a choice has to be made on further treatment required at the point of use.  The quality of mains water in the UK is good and the treatment processes effective, however, there are 25 water companies in England and Wales alone, each with its own treatment regimes.  It is essential that the POU distributor is aware of the water quality when installing new dispensers.  In fact, this should be part of the risk assessment when deciding on appropriate filters and dispenser types.

Information from Water Companies

The water companies are required to provide you with information for purposes of your risk assessment, as indicated by the Environmental Information Regulations 2004.  Information can include a description of their treatment process, data on historical cryptosporidium breakthroughs and whether special treatment has been used, such as additional filtration and use of UV.  Data on additives used to reduce lead migrating from old pipework and whether chloramines are used in the disinfection process should be available on request.  All this information should enable you to make a make a more informed decision about filter choice.

Typical Water Treatment

There is no typical water treatment because each company’s treatment process will have been worked out based on risk assessments of the source waters.  Generally, coagulation and filtration are the first stages using mixed media filters followed by a primary chlorination.  This chlorination stage will provide initial germ-kill and remove organic material by forming organo-chlorine compounds which are then removed by granular activated carbon beds.  Immediately afterwards the main dose of chlorine is added and allowed several hours contact time.

Special Treatments

Special treatments are put in place according to source water characteristics, for example, if animal waste contamination occurs frequently, special filtration and UV treatment would be employed to reduce risks of cryptosporidium breakthroughs.  If the distribution network is very long, chloramine treatment may be used to enable a more lasting disinfection during transit.  This is done by injecting ammonia in to the chlorinated water which forms the chloramine in situ.  Polyphosphate is added to the water supplies if the pH is low, to avoid lead being dissolved from the surfaces of old pipework.

Water Testing

Water companies provide a source of information to help you in making informed decisions about filters and dispenser specifications.  However, if you need an immediate answer, test strips are available which will indicate free chlorine, total chlorine (the difference will indicate whether chloramine is present), water hardness and pH.  However, you need to contact the water company to assess the risk of cryptosporidium contamination and for lead content.    

Monitoring Water Quality in Bottling Plants

        

Monitor your water quality with a range of diagnostic kits, such as Colilert®.  This measures presence or absence of coliforms and E.coli in source water.  Dipslides give a rapid indication of TVCs (Total Viable counts).   Ensure that your pipework is cleaned and disinfected with the correct cleaners and disinfectants. Hydrogen peroxide is an effective disinfectant which is taint-free and degrades to water and oxygen.  Foam cleaners, for larger surface areas, are available with alkaline, acidic and disinfectant properties.  Water sources are important, whether they originate from springs, boreholes or municipal supplies.  The water needs to be monitored to guarantee wholesomeness.  Our range of kits, test strips, cleaners and disinfectants will take care of the incoming water.  Water hygiene issues? Please call us for advice.

                            

                                                        Colilert® testing

 

                                                                        

                                                  

           Dipslides for Water and Surfaces

Taint in Bottled Water - Airborne Contaminants

Introduction

Bottled water is produced and distributed as a packaged food product and listed under food standards legislation in the UK.  The larger bottles seen on water dispensers in offices and other locations are a popular means of providing hydration to work forces in many industries and students in schools and universities.

Production, Storage and Distribution

The large 19L bottles are filled in a bottling plant and transported to distribution depots where they are stored for a while before delivery to customers.  When the bottles are empty, they are collected from the customer, returned to the distribution depot and subsequently forwarded to the bottling plant for washing and refilling.

Choice of Polycarbonate

Polycarbonate is the major plastic material used for the large 19L bottles.  This has many advantages over other plastic materials, for example, it is a clear, strong plastic which is durable and able to withstand the washing process at high temperatures without shrinkage or damage.  The disadvantage of polycarbonate is the porosity of the material when used in bottles.  Although the porosity does not affect any of the other bottle properties, there is a vulnerability to transmission of certain materials through the bottle walls which can then affect the taste of the water.  The porosity of polycarbonate has been studied and several scientific papers are available^{1, 2}.  The taste buds are very sensitive to minute traces of odoriferous materials in water.

Airborne Contaminants Affecting Taste

Materials with a strong odour, such as solvents, strongly flavoured foodstuffs such as garlic and coffee and certain chemicals will all affect the taste of water if kept in close proximity.  Of particular concern are highly volatile materials, such as volatile organic compounds, since the concentration of these can be very high near their source.  Small molecules are able to penetrate through polycarbonate more easily than larger molecules, for example, xylene is both volatile and a small molecule.  This is a component of paints and other coatings.

Proximity of Contaminants

It is a requirement of all distribution depots that no materials affecting the taste of water are allowed within the depot.  For example, diesel fork lift trucks are forbidden.  It is necessary at certain times of the day to open the roller doors to allow access for loading and unloading.  At this time, the bottled water is vulnerable to contaminants coming from the immediate outside environment.  This is particularly a problem with volatile contaminants such as solvents and other chemicals.  The choice of location of the depot is made with due consideration of near neighbours and any existing processes which could result in airborne contamination.  This sometimes limits the choice of location.

At the point where the roller doors are open, prevailing winds, down draughts, humidity or rain can markedly affect the ingress of contaminants that could affect water taste.

References 

1. D. S. Lee, K. L. Yam and L. Piergiovanni “Food Packaging Science and Technology”, CRC Press, Taylor and Francis Group (2008).
2. Valentina Siracusa “Food Packaging Permeability Behaviour: A Report” International Journal of Polymer Science, 2012 (2012) Article ID 302029, 11 pages.

Tap Hygiene in Hospitals

Many hospital departments have very high public usage of dispensers.  For example, in a major London hospital, the cooler located in A&E was in use 24hrs and, on average, 1000 cups were consumed over a time period when the average for other coolers in the hospital was 300 cups over the same time period.  The bacterial contamination at the tap outlets increased proportionally as the usage increased (survey previously commissioned by British Water Cooler Association).

Tap sprays containing disinfectants provide a simple way of reducing contamination and these are available from several suppliers.  Certain types of disinfectant spray produce a long-lasting effect, up to 30 days.  However, their use requires close cooperation between Facility Managers and the cooler providers to ensure that the coolers with the highest usage are treated more frequently.  Simple swab testing of the taps will enable the effectiveness of this intervention to be monitored. 

Radioactivity in Bottled Water

Objectives

The objectives of this short paper are to provide an easy understanding of the sources of radioactivity in bottled water, the regulated limits of the components causing radioactivity, types of analyses required, risks to human health and remedial actions where necessary.

Putting Risks in Perspective

Drinking-water may contain radioactive substances (radionuclides) that could present a risk to human health.  These risks are normally small compared with risks from microorganisms and chemicals that may be present in drinking-water.  Except in extreme circumstances, the radiation dose resulting from ingestion of radionuclides in drinking-water is much lower than that received from other sources of environmental radiation.  The United Nations Scientific Committee on the Effects of Atomic Radiation has estimated that the global average dose per person from all sources of radiation in the environment is approximately 3.0 mSv/year (the unit mSv is adopted as the measure of the effect of radiation on humans and is called “the Indicative Dose”).  Of this, 80% (2.4 mSv) is due to naturally occurring sources of radiation.  The maximum indicative dose set for drinking-water is just 0.1 mSv.

Indicative Dose for Drinking-water

The annual dose of 0.1 mSv for drinking-water is calculated from the alpha and beta particle levels in a sample of water taken at the point of filling and analysed at an accredited laboratory.  Alpha particles are positively charged and emitted by an atomic nucleus undergoing radioactive decay.  Beta particles are high speed electrons or positrons also emitted from an atomic nucleus undergoing radioactive decay.  They give a total measure of radioactivity from a sample of water measured in units called Becquerels (Bq/l).  The latest Directive (Council Directive 2013/51/EURATOM) sets out a procedure for demonstrating that doses from water supplies do not exceed 0.1 mSv per year (assuming a consumption rate of 730 litres per person per year).  This calculation is based on maximum alpha and beta particle concentrations of 0.1 Bq/l and 1.0 Bq/l respectively.

However, the WHO is at odds with these maximum concentrations and indicates that the maximum limit should be 0.5 Bq/l and 1.0 Bq/l respectively.  However, the EURATOM Directive will be put into the UK Regulations in November 2015, so we must comply with the lower figure for alpha particles.

Annual Water Analysis

Those companies producing between 100 and 1000 cubic metres of water daily must have an annual water analysis which includes alpha and beta particle concentrations.  If the values are less than 0.1 Bq/l and 1.0 Bq/l respectively, the indicative dose will calculate out at less than 0.1 mSv and no further action is necessary.  However if these values are exceeded, further analyses are required to determine repeatability and, if repeatable, analysis for other radionuclides must be done to determine the cause.  Many radioactive isotopes are naturally occurring, such as uranium and radium, which can contribute to high alpha particle readings.  Once identified, these materials can be eliminated by appropriate water treatment processes.

Risk Analysis

The additional risk to health from exposure to an annual dose of 0.1 mSv associated with intake of radionuclides from drinking-water is considered to be low.  Individual doses from natural activity in the environment vary widely.  The average is about 2.4 mSv/year, but in some parts of the world, average doses can be up to 10 times higher without any observed increase in health risks, as noted in long-term population studies.  An indicative dose of 0.1 mSv/year therefore represents a small addition to natural levels.

The nominal risk coefficient for radiation-induced cancer is 5.5 x 10^-2/Sv.  Multiplying this with an indicative dose of 0.1 mSv/year from drinking-water gives an estimated annual cancer risk of approximately 5.5 x 10^-6.

It should be clearly explained that guidance levels should not be interpreted as mandatory limits and that exceeding a guidance level may be taken as a trigger for further investigation, but it is not necessarily an indication that drinking-water is unsafe.

Recommendations and Going Forward

In the event that that alpha/beta particle results are consistently high, identification of the radionuclides causing this is necessary to enable remedial action.  For common radio nuclides which occur naturally, water treatment processes are available to remove them.  For example, uranium and radium can be removed by precipitation softening, ion exchange or reverse osmosis.  It may be possible to treat only part of water source and then blend it with untreated water to bring down levels to an acceptable level.

Conclusion

The new Directive will come into force in English Law in November 2015.  This will require an indicative dose of 0.1 mSv from 1 year’s consumption of drinking-water.  Initial screening has to be undertaken for alpha and beta activity on a yearly basis.  If below the levels of 0.1 Bq/l and 1.0 Bq/l, respectively, no further action to be taken.  If either of the screening levels is exceeded, the concentration of individual radionuclides has to be determined.  The outcome of this further evaluation will determine what further measures will be needed to reduce the dose, such as further water treatment processes.

Water Dispenser Sanitisation - How to Make it Cost Effective

Definition

It is important to understand the definition of “sanitisation” as used in Europe.  Sanitisation combines cleaning and disinfection in a single step.  “Disinfection”, on the other hand, is a single process which follows an initial cleaning step.

Techniques

The techniques used in dispenser sanitisation can be listed as follows:

·         Replacement of water contact parts by pre-sanitised or disposable components – reservoirs, reservoirs + tubing, taps

·         Manual cleaning and disinfection of components still in place

·         Auto-disinfection

Chemicals, Methods and Utensils

Chemicals include cleaners/acids and disinfectants.  Other methods include ozonation, steam treatment and hot water treatment.  Usual utensils are brushes, paper cloths and scouring pads.

Descalers

Acids are used for descaling reservoirs/piping and hot tanks.  Phosphoric acid is preferred and various concentrations are available from suppliers from 20-75%.  Increased concentration means more rapid descaling.  Some descalers contain detergents, which sometimes cause excessive foaming with heavy scaling.  Some descaling acids contain a disinfectant component, which enables descaling and disinfection.

Direct chill/spiral chill dispensers require a venturi doser to apply the descaler.  Push-fit fittings should be disconnected at the filter and the venturi doser connected.  Add 25-30ml acid, depending on the concentration, and draw into the dispenser with the chill tap.  Remember to rinse the push-fit fittings afterwards.

Disinfectants

Typical disinfectants are listed as follows:

·         Hydrogen peroxide

·         Hydrogen peroxide + silver ions

·         Peracetic acid

·         Ozone

·         Chlorinated materials

Hydrogen peroxide is highly effective against biofilm, leaves no taint and has harmless break-down products.  Peracetic acid is highly effective against biofilm, a small dosage is needed but residual product needs to be rinsed out thoroughly.  Chlorinated materials can create a taint issue if not rinsed out thoroughly and biofilm can resist.  An exception is chlorine dioxide, which leaves no taint and is very effective against biofilm.  The disadvantage of chlorine dioxide is that it has to be generated in situ because of stability issues.  However tablets are available, which generate the disinfectant on addition to water, although these are expensive.  Ozone can be generated with a portable kit and is effective against biofilm.  However it does create an ozone smell in the environment around the dispenser.  Steam provides effective sterilisation in 4 minutes with some units on the market.  However, care is needed in operation.

New Technologies – Auto Disinfection

Auto disinfection is possible with the following materials:

·         Ozone

·         UV

·         Hot Water

·         Silver and Copper

Ozone may be used by ozonating the water in the reservoir on a timed basis overnight.  Another technique ozonates the last section of the supply circuit prior to the tap outlet.  UV may be used to irradiate the reservoir contents or the water line just prior to the tap outlet.  A further technique irradiates the total tap outlet area.  Hot water disinfection uses hot water generated by the hot tank.  A microprocessor releases water into the rest of the dispenser and continues to heat until near boiling. 

Silver may be incorporated into plastic components.  This provides more of a bacteriostatic effect than germ-kill.  The treated plastic works well at low temperatures (5^oC), but is unable to cope at ambient temperature.  Copper is used in pipework.  It has a bacteriostatic action, but oxidation and subsequent passivation of the copper surfaces can reduce this effect.  Copper-silver alloys, unlike copper alone, can generate an electrolytic effect which provides better germ-kill.

Cooler Maintenance

Despite all the new technologies, a sanitary maintenance visit is still required to clean and disinfect the dispenser head, taps exterior and drip tray, otherwise poor in-house maintenance and difficult environments will always pose a problem for hygienic dispensing of water.  High-use dispensers are particularly vulnerable to tap contamination, including colonisation with Pseudomonas aeruginosa.  Sani-cloths may solve the problem for flat surfaces, but a disinfectant spray is necessary for tap areas.  A hydrogen peroxide spray provides a good germ-kill effect in the tap area, but the effect is not long-lasting.  New sprays are now available on the market which provide a long-lasting effect and these are to be recommended.

The Dangers of Drinking Pure Water?

100% natural pure water is difficult to find in nature.  As soon as rain hits the ground, it becomes mineralised.  Humans have been drinking mineralised water since they existed on earth.  If water is demineralised by reverse osmosis or distillation and we drink it, will this be something the body is not used to?  Will it do us any long-term harm?

The debate has been running for a long time.  If you look at the "The Natural Mineral Water, Spring Water and Bottled Drinking Water Regulations (England) 2006", the minimum hardness concentration in water sold to the general public must contain a minimum of 60 mg/l calcium.  However, hardness consists of a complex mix of polyvalent minerals, the main component of which is calcium.  Is adding a calcium salt to RO or distilled water up to 60 mg/l the same thing?  Probably not.

The reason often given for the need to maintain a minimum of 60 mg/l calcium is a body of epidemiological evidence that hardness in water has a benefit to cardiac health.  Does this infer that the absence of hardness salts could damage cardiac health?  Since the 2006 publication, the debate has continued over the years, with involvement of the Food Standards Agency, the WHO, The Scientific Advisory Committee on Nutrition and the bottled water industry, to mention a few.

A number of health aspects of water with or without hardness salts have been considered, including osteoporosis, hypertension, stroke, insulin resistance and epidemiological studies of water hardness (or lack of it) and cardiovascular disease.  These assessments are on-going and until a definitive conclusion is reached, water for human consumption, treated by osmosis or distillation, remains regulated at a minimum of 60 mg/l calcium re-mineralisation.

USE OF PHOSPHORIC ACID AS A DESCALER/DISINFECTANT IN COOLER SANITISATION

Phosphoric acid is sold as a descaler for application in cooler sanitisation procedures.  The manufacturers make no claim for disinfection and the technical data sheets refer only to use as descaler.  Disinfectants are highly effective at reducing microbial counts, even at very low concentrations, for example, hydrogen peroxide and peracetic acid.  Very strong acids will kill microorganisms, although their use in this manner is wasteful and can be dangerous.  However, a common problem with coolers is a tendency to build up both scale and biofilm and acids can be useful in helping to remove both.

In its simplest description, biofilm is a colony of microorganisms attached to a surface and protected by a self-generated protective film of polysaccharide.  This can occur in coolers and Pseudomonas aeruginosa is particularly adept at colonising surfaces and generating protective films.  Surfaces covered with scale are particularly susceptible to attachment by microorganisms.  They enjoy the ease with which a foothold can be made; smooth surfaces are more difficult to colonise.

Acids have the ability to dislodge and dissolve scale, provided the strength is high enough.  In dislodging the scale, they will also dislodge the attached biofilm and therefore help in its removal.  In this respect, acids will aid in removing microorganisms.  However, biofilm attached to plastic or stainless steel surfaces can resist  removal by acids, in fact older biofilms are very resistant to conventional chemicals such a phosphoric acid and chlorinated materials.  In this case the biofilm will remain intact and continue to protect the bacteria, including Ps. aeruginosa, gradually releasing the bacteria into their immediate environment over a period of time.  Oxidising acids, such as peracetic or nitric acids will attack biofilm successfully in this case.  Phosphoric acid is not an oxidising acid.

Phosphoric acid is a useful descaler in the cooler sanitisation procedure.  It will help in reducing microbiological count by removing scale which becomes coated with biofilm.  However it cannot be considered as an effective disinfectant and is not “heavyweight” enough to fulfil this role.  Descaling with phosphoric acid should always be followed by treatment with a disinfectant, such as hydrogen peroxide.

Simple Rules for Bottling Plants

1.       Segregation – The filling area should under a positive air pressure, to avoid inflow of contaminated air.  HEPA filters should be used to filter the air and these should be checked regularly to avoid blockage.  Either the filler should be treated in this way or the whole bottling plant should be under positive pressure if the filler is not enclosed.  Entry into the area must be limited to essential personnel wearing appropriate protective clothing.  Aseptic filling requires very high standards of hygiene and preferably should be run automatically and remotely from human participation.  When this is not possible, the operator should be specially trained to work in an aseptic environment.

2.       Process lines – The distance between the filler and capper should be as short as possible and likewise the distance between the blow moulding unit and the filler, although in the latter case this is not always possible.  Companies filling glass bottles must have a “glass breakage policy” to detail actions taken when glass breakage occurs.  If conveyor lubricants are used, these must be of the H1 grade (approved for indirect food contact).

Hygienic Design and Location of Bottling plants

1.       Site – avoid locations that could create problems in the future, e.g., nearby chemical works, rivers that may flood, farming environments.  The latter are a significant risk if animals are close by.  Transport of contaminants on footwear into the plant can be a big issue and there is a higher risk of pest infestation, both from flying insects and rodents.  Many bottling plants are located on farmland where the spring source originates.

2.       Building – the building must be fit for purpose and approved for food production.  It is unwise to use converted barns and the building should be purpose built.  A high-risk area should be defined within the building where product in open bottles is present.  The bottling plant should be sealed off from the external environment and no external doors should open directly to the outside.  Windows should be non-opening preferably or, at least , fitted with insect grills.  Glass should be strengthened and shatter-proof, this applies to windows, doors and lighting.  Drains should be fitted with traps and kept clear of blockage.  Toilets and canteen areas should not open directly into the plant area.  A hygiene and cleaning schedule needs to be created for the whole building based on the risk analysis highlighted by the HACCP programme.  External areas should be policed for excessive rubbish accumulation and encroachment of vegetation.

Sanitising Sealed Mains-Fed Water Coolers

Sanitising sealed mains-fed water coolers can be difficult but not impossible.  The main issue is how to get the descaling and disinfectant liquids into the unit. Typical units are the direct chill or spiral chill type.  Frequency for sanitising and filter changes is every 6 months.

The filter housing can be disconnected from the microbore tubing and a small device known as a venturi doser put in its place.  The doser is filled with the recommended amount of descaler and the hot tap actuated.  This will draw descaling acid solution into the tank.  After descaling, flush with at least 4 litres of water and test with pH paper until neutral.

The spiral chill pathways can be descaled and then disinfected using the same technique with respectively phosphoric acid (for example) and hydrogen peroxide.  The chemical is drawn from the doser by actuating the chill tap.  When the chemical begins to run from the tap (you can check this with pH paper or peroxide test strips), turn the tap off and wait for ten minutes.  Then flush with water until the test strips are clear.

This is not a detailed procedure and coolers vary considerably in design, however it will serve as a guideline.  Always check with your cooler supplier if in doubt.

Descaling and Disinfecting Water Coolers

The hot tank of coolers can be descaled using an acid such as phosphoric or citric. Sometimes other internal  parts of coolers need to be descaled and disinfected.  Scale build up in reservoirs, for example, is usually not severe but can lead to microbiological problems if left.  Attachment of micro-organisms and ultimately formation of a biofilm can rapidly cause deep-seated contamination which is not always easy to remove.

It is common practice to use a descaler, accompanied by mechanical action such as brushing, followed by a disinfectant such as hydrogen peroxide.  This will remove the scale and destroy the biofilm.  In some practices it is considered that one application of acid is sufficient to descale and destroy biofilm.  This is not always the case and is very dependent on the strength of acid used.  Very strong acids will do the job but these are usually applied diluted.

Diluted acids will remove scale more slowly and much of the acid is used up in this process.  In this case biofilm will not be removed.  If you want to use acid alone, then either use very strong acid (not recommended from a safety point of view) or use the acid in two steps, one to descale and the other to kill bacteria.

An alternative is to use an acid containing a disinfectant component which can then act as a sanitiser while removing scale.  These are available on the market.  However, the preferred method is to descale and then disinfect, in two separate steps.

Rapid Testing of Water Samples in the Bottling Plant

Following on from the ATP article in a recent blog, this section describes the procedure for rapid microbial testing of water samples.

Because water samples contain very few bacteria, an enrichment technique is employed. This involves taking a sample aseptically, and expelling it via a syringe through a special filter.

After waiting for 30 minutes to allow the microorganisms to recover from the stress of filtration, the filter housing is opened and the filter swabbed, using the special swab used in the ATP meter.

The swab is put back into the swab tube and activated using the snap and squeeze action. The swab is placed in the ATP meter and the measurement started. Results are recorded from the display.

Simple Microbiological Testing in the Bottling Plant

A new type of dipslide has recently appeared on the market which is double sided and able to detect 4 different groups of organisms:
1. Nutrient agar on one side to detect total counts.
2. Chromomeric coliform, E. Coli and pseudomonas aeruginosa on the other side.

It is a very versatile slide that can be used to dip into liquid samples or used as a contact plate on solid surfaces. The nutrient agar reacts with enzyme to produce a colour change which is specific to the bacteria type, allowing easy enumeration.

When sampling fluids, the sample is taken by immersing both sides of the paddle into the fluid to be tested. Excess sample should be gently shaken from the paddle before replacing in the container.

Surfaces can be sampled by allowing direct contact between the agar surface and the test material. The paddle is flexible and can be bent at the upper end to allow both surfaces to come into intimate contact.

Bacterial recovery rate is about 50% so that sweeping an area approximately twice that of the paddle will give a more accurate result. Afterwards incubate at 30/35 deg C for 24-48 hours, when full enumeration should be complete.

Apart from an indicator of aerobic bacteria (TVC), as shown in the picture above, the reverse side will give an indication of coliforms and Pseudomonas according to the following colour scheme: blue/purple or blue/green colonies = E.coli; pink/magenta colonies = other coliforms; buff colonies = Pseudomonas.

Recycling Plastics from the Bottling Plant

I previously attended a seminar run by the Food and Drink Association in the South West of the UK, entitled “Make Money, Not Waste”. This gave an up-to-date picture of latest developments in recycling and sustainability in general. My interest and perspectives were naturally focused on bottled water applications.

The main waste issues for bottlers are caps, 19L bottles and chemical drums, particularly the 25L size. Unfortunately all three items are made of different kinds of plastic which sometimes deters recyclers from collecting smaller quantities. If you are fortunate enough to be near a recycling site there may be an opportunity to drop off unwanted drums during the course of a delivery round by your drivers. However, this is not always convenient.

The organisation WRAP (Waste and Recycling Action Programme) currently has a study underway to collect plastics from smaller companies and deliver them to recycling points. This is useful for those companies who find it difficult to persuade recyclers to collect smaller quantities.

ATP Meters

Over the past ten years or so, a great deal of emphasis has been placed on the use of bioluminescence technology in the detection of microorganisms.

The mechanism by which fireflies produce a flash of light was first analyzed and identified by William McElroy in 1947. McElroy found that central to the light emission process was a specific enzyme reaction catalyzing the consumption of adenosine triphosphate (ATP).

In microbes, ATP can only be detected when living cells are present. It has since been established that the amount of light emitted from this reaction is directly proportional to the amount of ATP present. A high reading of relative light units (RLUs) indicates that the sample contains a high number of micro-organisms, provided that the background ATP level is low.

Unlike traditional testing methods, results from a bioluminescent reaction can be obtained quickly. Light is produced within seconds and can be measured with a luminometer (ATP Meter).

The current palm-sized instruments bring together state-of-the-art photodiode technology with simple user-friendly design to produce an affordable hygiene-monitoring system. Used with  ATP swabs, levels of contamination can be determined in just 15 seconds.

Key features of luminometers include, low cost, high sensitivity, compactness, simplicity in use, self- calibration with background check. Readings may be downloaded onto a PC or, as an optional extra, analysis software will provide spreadsheet-compatible data.

Preferred Bottle Wash/Sanitiser for Polycarbonate

New products specially designed for washing polycarbonate bottles are a rarity on the market. However, one new product provides many benefits for the bottler and gives that added confidence that the bottle is clean and germ-free. The product contains a food-safe disinfectant as well as the cleaning power of other products.

Extensive testing and trials have been carried out which show low TVCs, as expected, but also a reduction in the incidence of green bottles returning to the plant. The new product may be used under adverse conditions, for example, if the heater stops working or the throughput of bottles has to be increased because of production demand. If the concentration of the product is cranked up further, it behaves like a disinfectant and will pass the requirements for EN 1276.

The product generates slightly more foam than a regular bottle wash product, but rinsing is very rapid under normal conditions and the foam is controlled, particularly at normal wash temperatures.

The foam tracer makes the wash solution easier to see and provides reassurance that all parts of the bottle are being thoroughly washed. 

Taps for 25L Containers

The ability to reduce the manual handling of chemical drums can only be beneficial from a safety point of view. Pouring dangerous chemicals from a 25L container into a measuring jug is not the safest of procedures, but many plant operators do this.

As with many things, there is a simple solution. The cap/tap assembly illustrated in the photo provides a simple way of avoiding the lifting and pouring of chemicals. The cap replaces the standard cap and by simply punching out the centerpiece of the new cap, the tap can be screwed into the cap unit. In this way the drum can be left on its side, preferably in an elevated position, and chemical dispensed into the measuring jug via the tap.

The cap/tap unit is of robust construction and resistant to chemicals normally found in the bottling plants.