Author Archives: Staff

What is Adhol No. 10 and why use it?

An additive used for blending with Caustic Soda solutions supplying a source of active oxygen…

Adhol No. 10 is an additive used for blending with Caustic Soda solutions. It is specifically designed to boost the detergency of not readily saponified or hydrolysed soils by supplying a source of active oxygen.

adhol-10-30-kgs-liquid-r-hz

Adhol No. 10 is designed primarily for applications in Breweries, Beverage, Dairies and Food Processing plants; it is also suitable for use in other high care industries.

USE INSTRUCTIONS

In use concentrations of Adhol No. 10 are application dependent and should be established during trials. For occasional deep cleans, concentrations will typically be between one third to one half of the caustic v/v concentration. If Adhol No. 10 is used for routine cleaning lower concentrations should be used, typically between one tenth to one quarter of the caustic v/v concentration. Maximum concentrations will typically be
0.5% v/v. Cleaning temperatures should be optimised during trials, but for maximum benefit must be between 70 – 80°C. Temperatures should not be allowed to exceed 85 – 90°C, at this level the evolution of oxygen will be very rapid and the detergency benefit will be lost.

It is important to note that long term poor control of concentration through over dosing, poor control of temperature, or local hot spots could result in discolouration of Stainless Steel.

Adhol No. 10 is not designed for direct food contact.

The following are typical example applications, users should refer to Cleaning Instruction Cards for specific guidance. Other applications should be discussed with your Holchem Consultant. General Use. The addition of Adhol No. 10 to caustic causes the evolution of oxygen bubbles, these have a scouring and oxidising effect on soils.
Although Adhol No. 10 can be added at any point in a CIP or boil-out clean, it is better to run for approximately one third of the CIP cycle with caustic before adding Adhol No. 10.

A second additive can then be introduced two thirds of the way through the clean. Using this split dosing technique will reduce the potential for discolouration of Stainless Steel surfaces. Alternatively the dose should be delivered slowly over the entire cleaning cycle. Because Adhol No. 10 evolves oxygen bubbles it is essential to ensure that the circulation loop is vented, or, if fitted, pressure relief valves are operating.

In some applications excess foam may be generated, in these circumstances Adhol No. 10 can be used in conjunction with Defoam.

BENEFITS
· Adjustable rate of addition to meet requirements.
· Cost effective.
· Boosts performance of caustic solutions.

 

Consultancy Corner – Master Brewer Mark Tetlow

Introduction to services…

mark tetlowCan I introduce myself?

My name is Mark Tetlow BSc Brew. Dipl Brew.

I have been working in the brewing industry for the last 30 years.

I am the founder of The Beer Hub – a valuable resource for brewers and publicans.

mt@thebeerhub.co.uk

www.thebeerhub.co.uk

The Beer Hub exists to offer a range of Consultancy Services allowing brewers and publicans to to ensure the safety, quality and consistency of serve.

beer hubThe Beer Hub also offers a range of beer events that can be tailored to meet your needs. These events are a great way to educate and enthuse your staff while raising the profile of your beers.

One area I am keen to help brewers and pub owners with is supporting the quality of their beers in trade. Recent articles I have  written for Cellar Craft have had very positive responses from the industry and has led on to me working with a number of companies who have identified that the integrity of their brands can be seriously affected by poor practices at the point of dispense.By designing and delivering bespoke onsite training and support packages The Beer Hub is able to help mitigate some of these issues.

beer hubWorking with a local micro brewery I have developed a beer brand BeerHub #1 a golden ale that is dry hopped with Mosaic hops to give it a soft apricot fruity nose.

The beer came second in the local CAMRA beer festival and is now sold in a number of pubs across the Midlands. I also work with big and small brewers covering everything from brewery start ups to supporting a National Brewers craft ale strategy and even acting as a consultant to a client looking to introduce Kombucha, fermented tea, into the market.

A bit about me

mark tetlow 2

After graduating from Heriot Watt Brewing school I have worked for a number of regional brewers namely Sam Smiths, Marston and latterly at Everards where I was the Quality Assurance Manager responsible for the quality of their products from raw materials through to final beer dispense.

I have been very fortunate to work in all areas of the brewing process and also to work within the trade which I believe gives me a unique insight as not many brewers can claim to have worked from grain to glass. Part of my responsibilities have been to run Technical Services departments and in this role I have been involved in training and auditing licences to ensure that the quality products brewed in the brewery are served to the end consumers as the brewer intended.

Over the last 10 years I have run numerous Meet the Brewer events in pubs and venues across the country, speaking to over 8000 customers sharing my passion for beer, brewing and beer food matchings.
In 2016 I successfully gained the Beer Academy’s Beer Sommelier award becoming the first Beer Sommelier in Leicestershire. I now train on behalf of the Beer Academy and run customer beer classes across the UK. I have also written articles for the press and spoken on the radio about beer and beer and food matchings.

Please take a look at The Beer Hub for a full description of the areas that I cover.
Tel: 07752 200280

Consultancy Corner – Master Brewer Martin Cullimore

cullimore

E-mail: martin@cullibrew.com                                                          Mobile: 07793 47 25 47

         Website: Cullibrew.com

 

martin

Master Brewer [Institute of Brewing & Distilling]

I have over 40 years experience as a professional Brewer.

The Beers I have brewed have won numerous awards including the CAMRA Beer of the Year.

I have extensive experience in innovation including new product development and new packaging formats.

I was the longest serving Head Brewer in the country.

I can offer professional advice on:

  • All aspects of Brewing, Fermentation & Packaging techniques
  • Technical troubleshooting
  • Yeast Handling
  • Sensory Training [Flavour Identification/Taste Panel Training]
  • Brewery Auditing
  • Brewery Plant Design & Commissioning
  • Plant Cleaning & Sterilization
  • Raw Material Specification and Purchasing
  • Quality Control
  • Quality Assurance [SALSA & FSQ]
  • Packaging innovation e.g. KeyCask, KeyKeg.
  • Health & Safety including Risk Assessments
  • Food Safety/HACCP Systems
  • HMRC Beer Duty
  • Microbiology

Additional Skills/Qualifications/Information

  • Qualified Taster Trainer
  • HACCP Level 3
  • Health & Safety
  • Risk Assessments
  • C.O.S.H.H.

Cleaning in the Brewery with Murphy and Son

There are three basic standards of cleaning

  1. Physically Clean – visually clean
  2. Chemically Clean – clean to a standard where anything coming into contact with the surface suffers no chemical contamination.
  3. Microbiologically Clean – clean and sterile so that there is no physical or micro-biological contamination.

Keeping you brewery clean

This table outlines the standard required for various parts of the brewing process:

Process Plant Soil Type Cleaning Procedure Cleaning Criteria Chemicals
Milling Mills and Rollers Dust Manual Physically clean None
Mashing Mash Tun Particulate sugar, scale, tannin Manual or CIP Chemically clean Detergent
Boiling Copper Starch, sugar, hop residues, scale, tannins Manual or CIP Chemically clean Detergent
Cooling Para-flow Particulate protein scale Manual, CIP or both Micro-biologically clean Detergent & Sanitiser
Fermentation F.V.’s Yeast, Tannin, Sugar, Scale, Protein, Oxidation products Manual or CIP Micro-biologically clean Detergent & Sanitiser
Conditioning Closed Vessels Yeast, Protein, Scale CIP Micro-biologically clean Detergent & Sanitiser
Packaging Casks Yeast, Protein, Scale CIP Micro-biologically clean Detergent & Sanitiser
Cellar Beer lines Yeast, Protein, Scale CIP Micro-biologically clean Detergent & Sanitiser

The choice of cleaner employed will be dependent upon the nature of the deposits found in a particular environment and on the cleaning criteria. Generally speaking organic deposits such as proteins, gums, yeast, sugars and hop residues are most efficiently removed by caustic based cleaners, whilst inorganic scale is removed by acidic cleaners. The materials of construction of the plant are also critical, caustic soda based cleaners for example being aggressive to Aluminium.

For more information please click here.
Murphy’s supply and number of brewery hygiene products.

Addition of Copper Finings Murphy and Son Ltd

General Considerations

• Copper finings are derived from seaweeds and the active ingredients are carrageenans and furcellarans. They are available as dried seaweed, e.g. Irish Moss, or as extracts in the form of either pellets or powders.
• Copper finings can be added directly to the copper. Alternatively powders can be slurried with cold liquor prior to addition.
• The optimum rate of addition of finings should be determined annually when starting the new season’s malt or whenever there is a change in the type or supplier of malt.
• The rate of addition of finings will affect the clarity of both hot and cooled wort. Incorrect addition of copper finings (both over and under) can give poor fining action in the cooled wort and beer which fines with difficulty.

Range of Values

• Optimum rates of addition may vary from one malt variety to another, from season to season and from brewhouse to brewhouse. Murphys are happy to offer an annual optimisation service to our customers, either in our labs or on-site.
• Typical rates of addition are in the order of 1·0 – 5·0 gms per Hectolitre (10 ppm to 50 ppm, 1·63 – 8·15 gms per barrel).• Hot breaks should consist of large flocs in bright wort. Cold breaks should be a heavy fine sediment in bright wort.
• The haziness of worts from the heat exchanger should be within the range of 2 – 6 E.B.C. haze units. If worts are too bright fermentation problems are sometimes encountered because the release of carbon dioxide and consequent ‘stirring action’ that such a release promotes, are hindered.

Operational Protocols

• When casting to a hop-back, finings are added during the last 5 to 15 minutes of boiling. If the practice is to recycle worts at the hop-back finings can be added at this point. When using a Whirlpool, finings should be added at casting from the copper.
• Whatever method of addition is used the copper finings must be evenly dispersed.
• Rates of addition should be optimised according to results obtained.

Measurement Protocols

• The formation of hot breaks is assessed visually after sampling from the copper at casting.
• Cold breaks are assessed visually after sampling from the cold wort mains and allowing to stand for a minimum of 2 hours.
• Rate of addition of finings; a graph is drawn of casting, gravity against rate of addition of copper finings and breaks are indicated as excellent, good or poor. The rate of addition is altered when poor results are observed.

Kettle Finings at Murphy & Son

Brewing Audit

Build up of Beerstone

NIPAC B  – Beerstone Remover

Corner-Technical

Beerstone removal

As a brewer you may have a problem with beerstone build-up in brewing vessels and containers.
Beerstone is a compound called calcium oxalate, and if not completely removed can harbour microorganisms. Beerstone is a common factor in wild yeast infections within breweries, it can also act as a nucleation point and cause gushing.
The removal of this material is carried out by using a concentrated formulation of nitric and phosphoric acids.

Nipac B is designed primarily for this application in breweries and is formulated to be low foaming and is suitable for use in recirculation applications. It can be used as an alternative to caustic based detergents in breweries for the cleaning of bright beer tanks and tankers whilst under CO2 atmosphere. A gel version exists for manual application where recirculation of the product is not possible.

https://murphyandson.co.uk/store/75-beerstone-removal

BENEFITS OF NIPAC B

· Excellent mineral and protein removal
· Aids removal of beer and milk stains
· Safe for use on Stainless Steel
· Can be used under CO2 atmospheres
· Suitable for use in CIP applications.
For more information and dosage rates please click on the following:
NIPAC B Technical Data sheet. Please contact our sales line or sales email to purchase this product.

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Hygiene from Holchem

Function of Auxiliary Finings

Auxiliary Finings

General Considerations
• Auxiliary fininqs aid the action of isinglass finings by enhancing the total negative charge, especially when contribution by yeast is low. This improves the electrostatic interaction between proteins and isinglass finings. Beers fine more quickly because of the larger floc size.
• Auxiliary finings are available in solution as acidified polysaccharides, silicates, alginates and formulated blends.
• Factors which need to be considered are the type of auxiliary finings, dosage rate, storage temperature and conditions, time of addition, fining performance, yeast count prior to fining and compactness of sediment.

Range of Values
• Sulphur dioxide content of liquid auxiliary finings is typically between 200 and 300 mg per litre.
• Solutions of auxiliary finings should be visually bright prior to use.
• Yeast counts are typically 0·5 x 106 – 2 x 106 cells per ml with a mean of 1·0 x 106 cells per ml.
• The dosage rate of auxiliary finings is typically 0·9 – 3·5 ml per litre (¼ – 1 pint per barrel), but is related to the isinglass dosage rate and depends on compactness of the sediment.

Operational Protocols
• Liquid auxiliary finings are stabilised with sulphur dioxide and stored in inert containers at ambient temperature There must be adequate ventilation in the storage area because levels of sulphnr dioxide particularly on delivery can be high.
• Addition is made in-line through a dosing pump as beer is transferred from fermenting vessel to racking tank or directly to tank or cask
• Addition of alginate auxiliary finings is made at least 4 hours before addition of isinglass finings. Due to the rapid action of silica based auliliaries they can be added either pre- or post-isinglass finings. The actual time of addition is determined by experience.

Measurement Protocols
• Every batch of finings should be inspected visually and examined for infection by micro- organisms.
• Fining action is monitored by making the equivalent addition of finings to appropriate samples of beer and noting daily the size of flocs, speed of fining action and clarity of fined sample
• A nine gallon cask is fined and stillaged in the sample cellar for a larger scale production check on the fining performance
• Finings contribute to sulphur dioxide levels in beer The levels of sulphur dioxide in samples of fined beer should be measured. Auxiliary finings supplied by Murphy & Son Ltd. will add in the order of 0·25 – 1 ppm SO2 to the beer at typical addition rates.

Take a look at our Auxiliary finings range

 

MURPHY AND SON LTD JOB VACANCY – LABORATORY MANAGER

Job Advert – Laboratory Manager

This role entails the management of all laboratory staff (currently a team of 6), in both Chemistry and Microbiology laboratories.

Work carried out in the laboratories covers: Quality Control testing of raw materials and all products manufactured on site in accordance with the ISO9001 Quality System, testing of samples supplied by customers and testing under the UKAS ISO 17025 banner.

The day to day duties involve:

Management

  • To coordinate both chemistry and microbiology laboratory staff on a day to day basis
  • To set and measure productivity targets
  • To undertake annual appraisals for all laboratory staff
  • To carry out one to one meetings and review staff objectives
  • To hold regular laboratory meetings
  • To train laboratory staff in relevant laboratory roles
  • To attend weekly management meetings
  • To liaise with other managers with regards to any company business that involves the laboratory

Laboratory

  • To confirm Quality Control testing of manufactured products and sign off batch cards
  • To compile laboratory reports to send out to customers
  • To liaise with customers regarding samples and to discuss the relevance of test results
  • To field customer technical queries via email and telephone
  • To provide laboratory testing quotes to customers
  • To liaise with the Technical Sales Representatives with regards to any specific customer analyses/trials
  • To ensure laboratory consumables are ordered and stock levels are correct
  • To provide cover in the absence of other laboratory staff
  • To develop and promote new methods and test procedures, in conjunction with the Product Manager and the R&D team
  • Extend the range of UKAS accredited testing offered to customers

Quality

  • Liaise with the Compliance department to meet the needs of and QRESH objectives
  • To carry out internal audits
  • To assist with external auditors on the day of auditing
  • To undertake the role of UKAS Quality Manager and UKAS Deputy Technical Manager

Attributes

  • Be a good all round manager
  • Have good communication skills
  • Have knowledge of good laboratory practices
  • Have knowledge of ISO9001 Quality Management systems
  • Have knowledge of ISO17025 UKAS systems
  • Preferably knowledge of BRC standards
  • Knowledge of the brewing, food and beverage industries would be an advantage
  • Have experience of working in, and preferably managed, a chemistry or microbiology laboratory

Hours: 8.30 – 5.00 Monday to Friday

Holidays: 22 days plus bank holidays rising to 25 days.

Salary: £28,000-£32,000 depending upon experience.

training day

If you would like to apply for the above position please could you send  your CV and a covering letter to Joanne.taylor@murphyandson.co.uk all applications will be treated as confidential.

The closing date for all roles is Friday 26th May at 12.00pm.

 

 

Water, Water Everywhere. Murphy and Son Ltd

Water, Water Everywhere

We take treating your liquor very seriously at Murphy’s. If you purchase any of our liquor treatments please remember you are entitled to a free liquor analysis and our technical support. We will recommend the most suitable treatment for your brewery.
Send in 50ml of your water to our Laboratory

Send in 50ml of your water to our Laboratory

Introduction

Beer contains approximately 90% water, and the importance of the liquor to final beer quality cannot be over-estimated. Historically a correlation was observed between the liquor composition of an area and the type of beer that the region could best brew. The Pale Ales of Burton-on-Trent and Edinburgh, Porters of London, Stouts of Dublin and Lagers of Pilsen are classic examples. Water falling as rain, hail, sleet or snow is pure, but dissolves gasses such as oxygen and carbon dioxide from the atmosphere. On reaching the ground the water runs off into rivers, streams and lakes and on in some cases to reservoirs. The composition of the water in the reservoirs is dependent upon the nature of the catchment area. In areas where the rocks are hard, the water will not penetrate deeply, and will be ‘soft’ – that is low in dissolved salts. In areas where the rocks are more permeable – gypsum obrewing liquorr limestone for example – water will penetrate readily and dissolve many minerals on its way to the reservoirs to become ‘hard’.

The water supplied by local Water Authorities is required to be potable – that is fit to drink and free from pathogenic organisms. In order to reduce microbiological counts chlorine will usually be added, but the water is not sterile. Fortunately however the micro organisms found in water are not beer spoilage organisms, being unable to survive the conditions of high ethanol and hop resin levels and low pH found in beers. So the objective of liquor treatment is to convert the water sent to us by the Water Authorities into acceptable brewing liquor. This we achieve by the removal of unwanted ions and addition of required levels of desirable ions

DWB Liquor Treatment from Murphy's

DWB Liquor Treatment from Murphy’s

Calcium

Of the ions required for brewing, calcium is by far the most important. This is because of the acidifying effect that calcium has on the wort.

Wort contains large amounts of phosphates derived from the malt, and these have a buffering effect – that is they tend to mop up hydrogen ions and keep the pH higher than desired. Calcium ions precipitate phosphates as insoluble calcium phosphate and release hydrogen ions into the wort. It is worth mentioning at this point that whilst the pH of the wort is critical, that of the water in the HLT is not. The pH of water may vary from about pH 5 to pH 8 dependent upon the levels of dissolved carbon dioxide – even de-ionised water can have pH levels as low as 5 after exposure to the air. However the carbon dioxide is driven off by heat in the HLT and the pH of the water will rise.

A combination of the presence of calcium ions and the decrease in pH has a number of effects on the brewing process:

The lower pH improves enzyme activity and thus wort fermentability and extract.

The optimum pH for ß-amylase activity is about 4·7. Wort produced from liquor containing no calcium has a pH in the order of 5·8 – 6·0, compared to values in the range of 5·3 – 5·5 for worts produced from treated brewing liquor. The activity of the ß-amylase then is greatly enhanced by the addition of calcium, this exo enzyme increasing the production of maltose from Amylose, and thus making worts more fermentable.

Calcium has an almost ‘chicken and egg’ effect in the precipitation of wort proteins, both during mashing and during the boil.

Protein-H + Ca2+ Protein-Ca + 2H+

The hydrogen ions released further reduce the pH which encourages further precipitation of proteins. Proteins are also degraded, that is converted to simpler substances by proteolytic enzymes called proteases. These are found in the malt, and have optimum activity at pH values of about 4·5 – 5·0. The reduction in pH then caused by the presence of calcium encourages proteolysis, further reducing protein levels and increasing wort Free Amino Nitrogen levels (FAN). FAN compounds are utilised by the yeast during fermentation for the manufacture of Amino acids, and an increase in FAN levels in the wort improves the health and vigour of the yeast. High protein levels in beers also have negative effects, making beer more difficult to fine and encouraging formation of hazes, in particular chill hazes. Product shelf life can also be adversely affected.

Calcium ions protect the enzyme a-amylase from inhibition by heat.

a-amylase is an endo enzyme, cleaving the internal 1,4 glucosidic links of amylopectin resulting in a rapid reduction in wort viscosity.

It can be seen then that the presence of calcium has positive effects on the activity of both a-amylase and ß-amylase, two of the most important enzymes in the brewing process.

The drop in pH encouraged by Calcium ions in the mash and copper helps afford the wort and subsequent beer produced a greater resistance to microbiological infection.

The reduced pH of the sparge liquor reduces extraction of undesirable silicates, tannins and polyphenols from the mash bed.

The extraction of such materials is encouraged by alkaline sparge liquor. These materials are very undesirable, contributing to harsh flavours, hazes in the finished beer and decreased beer stability.

Calcium precipitates oxalates as insoluble calcium oxalate.

This again occurs in both the mash tun and the copper. Oxalates cause hazes in finished beers and also contribute to the formation of beerstone in FV’s, CT’s and casks. Oxalates are also thought to promote gushing in certain beers, although this is not generally a problem to the micro brewer.

The presence of calcium reduces colour formation in the copper.

This is due to the reduction of extraction of colour forming compounds such as anthocyanogens and pro-anthocyanidins during the sparge. The reaction: Reducing Sugar + Heat Melanoidins is also inhibited.

Calcium ions improve beer fining performance.

Calcium ions encourage yeast flocculation – being a divalent Cation it has a natural affinity for negatively charged yeast cells.
With all the above advantages of the presence of calcium and reduction in pH there is one minor disadvantage.

The reduction in pH causes a decrease in hop utilisation, giving less bitter beers.

This increases hopping costs, since more hops will be required to achieve a desired level of bitterness. However the optimum pH for hop isomerisation as used in the commercial production of isomerised hop extracts is about pH 10, so a reduction from pH 5·8 in a mash with untreated liquor to pH 5·1 out of copper for a treated brew is not too critical.

You will see that much of the calcium added to the mash is lost – precipitated out as phosphate, proteinate or oxalate. Since calcium is specifically required in the copper for further precipitation of these materials it is common to add calcium to the grist or Hot Liquor Tank and to then make a second addition to the copper. Where this is not practical it is quite acceptable to make a larger addition to the grist or to the H.L.T.

Bicarbonate

This ion needs to be very closely controlled in order to achieve good beer. High levels of bicarbonate cause high pH values throughout the brewing process according to the equation:

It should be noted that bicarbonate ions are rather more effective at raising wort pH than calcium ions are at reducing it.
The conversion of bicarbonate to carbonic acid is reversible until heat is applied, which drives off the carbon dioxide. This effectively removes the acidic hydrogen ion from the system by using it to form a stable water molecule. The wort pH therefore remains high and all the advantages derived from the presence of adequate calcium levels and reduced pH are lost.

We therefore see the following:

  • Harsh after-tastes in the finished beer
  • Extract will be reduced due to lower ß-amylase activity
  • Reduced protein precipitation due to high pH
  • Worts and beer more prone to infection
  • Increased extract of undesirable materials in the sparge, notably silicates, polyphenols and tanning

The net result of this is then to decrease beer stability and shelf life and to increase the likelihood of troublesome hazes. Colour will be darker, and flavour will be detrimentally affected. Hop utilisation will be increased, giving more bitter beers. It is then essential to ensure removal of excess bicarbonate. You will recall from Figure 1 that a hard water may contain 250 mgs/l of bicarbonate. The maximum level that can be tolerated without adverse effect for the production of pale ales is 50 mgs/l, and the preferred level would be about 25 mgs/l. It should also be noted that whilst additions of calcium may be made to HLT, grist and copper, the removal of bicarbonate must be achieved in the Hot Liquor Tank.

This may be done in a number of ways:

Deionsiation: Very effective, but high capital and revenue costs.

Lime treatment: Addition of carefully controlled amounts of lime (calcium hydroxide) to the HLT will precipitate the bicarbonate as calcium carbonate.

There are 2 major drawbacks:

  1. The amount added needs to be exactly calculated and over addition may result in an overall increase in alkalinity.
  2. The precipitated calcium carbonate can form a sludge on the bottom of the HLT that will need periodic cleaning.

Boiling: This again is a traditional method of removal of bicarbonate (Temporary Hardness) but again has 2 drawbacks:

  1. Very expensive.
  2. Only effective where the alkalinity is present as bicarbonate. If the levels of sodium, potassium or magnesium carbonates or hydroxides present are significant boiling will not be effective.

Acid Treatment: Now the most widely used method, for a number of reasons:

  1. Relatively inexpensive.
  2. Easy to use and does not produce sludge in the HLT
  3. May add desirable anions – sulphate or chloride.
  4. Can use phosphoric or lactic acids if no anions are wanted – eg for lager beers.
AMS Murphy and Son Liquor Treatment

AMS Murphy and Son Liquor Treatment

It is essential to rouse the liquor when acid treating in order to encourage the removal of the carbon dioxide. This can have corrosive effects on the materials of construction of HLT’s if left in solution.

Magnesium:

Is an essential element of brewing liquor because it is required by yeast as a co-factor for the production of certain enzymes required for the fermentation process. It is invariable formulated into liquor treatments at relatively low levels.

However caution must be exercised for 3 reasons:

  1. Excess magnesium can interfere with the reactions of calcium because its phosphates are more soluble
  2. Above about 20 mgs/l magnesium can give beer a sour and bitter taste
  3. In excess magnesium has a laxative effect

Sodium:

Is present in all beers. Excessive levels are undesirable as it imparts a sour and salty taste at high concentrations. The flavour is more acceptable when the sodium is present as chloride than as sulphate.

Potassium:

Is, like magnesium, a yeast co-factor and is required at trace levels for satisfactory fermentations. It is more acceptable than sodium from a flavour point of view, giving a salty taste without the sour notes. It is also gaining some favour as Doctors warn of the effects of high sodium intake on blood pressure. However potassium salts are very much more expensive than the sodium equivalents, and in excess potassium has laxative effects on the beer.

Sulphate and Chloride:

It is convenient to discuss the effect of these two ions together. Much is made in brewing literature of the impact of these ions on beer flavour characteristics – sulphate gives beer a drier, more bitter flavour, whilst chloride imparts palate fullness and to an extent sweetness. However what must be noted is that it is the ratio of the concentrations of these two ions that is significant, rather than simply the actual concentrations. A ratio of about 2:1 sulphate to chloride is about right for a bitter beer, and it makes little difference if the actual values are 500:250 or 350:175 mgs/l. As will be seen in Figure 3 ratios of 1:2 sulphate:chloride are recommended for mild ales, whilst a ratio of 1:3 may give best results for stouts or porters.

Sulphate and Chloride: It is convenient to discuss the effect of these two ions together. Much is made in brewing literature of the impact of these ions on beer flavour characteristics – sulphate gives beer a drier, more bitter flavour, whilst chloride imparts palate fullness and to an extent sweetness. However what must be noted is that it is the ratio of the concentrations of these two ions that is significant, rather than simply the actual concentrations. A ratio of about 2:1 sulphate to chloride is about right for a bitter beer, and it makes little difference if the actual values are 500:250 or 350:175 mgs/l. As will be seen in Figure 3 ratios of 1:2 sulphate:chloride are recommended for mild ales, whilst a ratio of 1:3 may give best results for stouts or porters.

Sulphur is essential for the fermentation process, since the yeast needs to manufacture the two sulphur containing amino acids, cysteine and methionine. Some yeast strains will use sulphur from sulphate ions for this purpose and will then excrete any excess as sulphite ions. These can then be reduced to form hydrogen sulphide or sulphur dioxide. Both of these materials have characteristic pungent odours and even at low levels can give unacceptable sulphury noses to the beer. Bacteria also have the ability to produce a wide variety of sulphury off flavours, including rubber, garlic and cooked vegetable.

Nitrate:

Levels of Nitrate are beginning to drop generally due to greater control of the use of nitrogenous fertilisers. Nitrates themselves are not a problem at levels below 50 mgs/l, however they can be reduced by yeast or bacteria to form Nitrites. These ions can then react with wort amines to form Nitrosamines, which are carcinogenic.

Trace Ions:

Metals such as Iron, Manganese, Copper and Zinc may be found in small quantities in water and are all utilised by yeast at levels below 1 ppm. Higher levels can cause colloidal hazes and metallic off flavours, particularly with higher levels of Iron. Silica should also be at very low levels in brewing liquor because of the likelihood of colloidal hazes being formed. Ammonia should be absent in brewing liquors, being indicative of contamination by sewage. Fluorine, present in most waters at about 1 ppm for dental purposes, has no detectable effect on the brewing process. However Chlorine, used for sterilisation, may be at relatively high levels at certain times of the year. This can cause problems since chlorine is a very reactive chemical and will readily react with organics to form chlorophenols. These have a medicinal (T.C.P.) flavour which is in some cases detectable at levels below 1 ppb. Chlorine will be lost to some degree by the heat in the Hot Liquor Tank, but not all water used within the brewery is from that source. Some brewers may use untreated liquor to break down to gravity in fermenter, and rinsing following caustic or acid cleaning cycles will typically be with untreated mains liquor. One solution is to treat both Hot and Cold Liquor Tanks with 10 ppm of Salicon Liquid 169 (20 mls in 10 brls liquor) and rouse vigorously to remove the chlorine. The sulphur dioxide reacts with chlorine in the manner described below – reducing reactive, undesirable and potentially harmful chlorine ions to chlorides.



Typical Liquor Analyses for Beer Types:
Bitter Mild Porter Lager
Calcium 170 100 100 50
Magnesium 15 10 10 2
Bicarbonate 25 50 100 25
Chloride 200 200 300 10
Sulphate 400 150 100 10

Nitrate – As low as possible
Metals – Zn, Cu, Fe,Mn Less than 1 ppm All figures are in ppm (mgs/ltr)

ams200

AMS Liquor Treatment

Please take a look at Murphy’s Liquor treatment range.

 

WE HAVE A FEW SALE ITEMS

Due to all our new developments in the warehouse and production plant we have stumbled across a few stock items that are either obsolete or are nearing or past their best before date but still have good activity.

Yeast Quantity Best Before Price per pack
Mauri AWRI 1503 500g May-17 £23.44
Mauri Lager 497 500g Feb-17 £4.50
Munich Wheat Yeast 500g May-17 £30.56
Safspirit Malt Whiskey 500g Mar-17 £22.59
Safspirit American Whiskey 500g Jan-18 £21.19
Safspirit Fruit 500g May-17 £19.70
Safspirit Grain 500g Apr-17 £21.66

If you are interested in any of the above products please contact: frances.maud@murphyandson.co.uk