Brewing Microbiology Practical Knowledge & Application by TPM methodology m ethodology (non-yeast) Le Quang Hai V B L G r o u p - T ec ec h n o l o g i c a l C o n t r o l l er er V B L M ic ic r o b i o l o g y W o r k s h o p 2009 Feb
Chapter 1
Brewing m icrobiology
Chapter 1
Brewing m icrobiology
Micro-organisms
During production of beer, several micro-organisms are likely to grow because of nutrient-rich environment (sugar, amino acid, phosphate, sulphate, oxygen, vitamins, minerals…) and suitable conditions (temperature, time, pH…)
However, characteristics of beer – beer – alcohol, CO2, SO2, pH – pH – reduce the range of organisms. Examples:
Lactobacillus (L.brevis, L.lindneri, L.brevisimilis, L.frigidus, L.coryniformis, L.Casei…)
Pectinatus cerevisiiphilus
Microbiological defect and off-flavor Sensation
Bacterium
O2
Phenolic, Smoke, DMS
Enterobacter - Aerogenes - Klepsiella
+
Wort, Fermentation
DMS, H2S
Flavobacterium - (Obesum)
_
Wort
Celery
Aerobacter Escherichia
_
Fermentation
Sweat, Cheese, Iso-valeric acid
Megasphera
_
Wort, Fermentation
Milky, Vingar, Propionic acid
Pectinatus Cerevisiiphilus
_
Wort, Beer
Rotten apple, H 2S
Zymomonas
_
Beer
Vinegar
Acetobacter
+
Wort, Beer
Diacetyl, Sour
Pediococcus Lactobacillus
Buttery, Cheese, Rancid
Clostridium
_
Adjuncts, Wort
Apple, Vinegar
Acetomonas / Gluconobacter
+
Beer
Phenolic, Smoke
wild yeast
Anise
wild yeast
_ or trace of oxygen is required
_ _
Process stage
Wort, Fermentation, Beer
Wort, Fermentation Wort, Fermentation
Micro-organisms (ex: flourescence method)
Reclamation of beer spoilage in Germany
Micro-organism type
With requirement of Oxygen
Group
Aerobic Env
Anaerobic Env
O2 effect
Obligate Aerobe
Growth
No growth
Use O2 as a food electron acceptor in aerobic respiration
Microaerophil
Growth if O2 level not to high
No growth
Required O2 < 0.2 atm
Obligate anaerobe
No growth
Growth
O2 is a toxic substance
Facultative aerobe / anaerobe
Growth
Growth
Not require O2 to growth but utilize it when available
Aerotolerant anaerobe
Growth
Growth
Exclusively anaerobic (fermentative) type of metabolism but not insensitive to the presence of O2. Not required O2 and not utilize it
Organism grows from 1 – 108 times in less than 9 hours when circumstances are ideal
Micro-organism type (cont)
With temperature
Psychrophiles (cold)
: 0 – 300C
Mesophiles (medium)
: 20 – 500C
Thermophiles (hot)
: 40 – 700C
With acid degree or pH value
If 6 < pH < 8: optimum for micro-organisms
If pH < 4: growth of most bacteria limited (except for acid tolerant bacteria
With water and other nutrient (sugar, minerals)
Osmophilous: growth in medium wealthy on sugar
Xerophilous: growth in medium poor in water
Halophilous: growth in medium wealthy on salt
Bacteria growth is limited with less water
Prevention of infection
Sanitary mindset of personel
Good housekeeping
Hygiene design of equipment
Hygiene maintenance
Efficiency CIP (cleaning and disinfection)
Monitoring through reliable microbiological control procedures
Chapter 2
B i o f o u l i n g a n d B i o f i lm
Source: IWW Water Center, Mulheim an der Ruhr, Duisburg Essen University Markus Timke, Analysis of Biofilm com munities in Breweries, Biologies/Chemie der Universitat Osnabruck
What are bio-fouling and biofilm
Fouling: undesired deposit of materials on surface
Organic: deposit of fat, oil, protein…
Inorganic: precipitation of inorganic crystal or scaling
Particle: silt, clay, humid particles
Bio-fouling: undesired deposit and growth of microorganisms on surface – particles (interface) which can multiply on the expense of nutrient
Biofilm: is a matrix of extracellular polymeric substance (EPS), associated with working materials, corrosion products, debris, soil, particles, etc
Biofilm includes films on surface, flocs, (floating biofilms), mat and sludge – all kinds of cell in matrix
Examples of biofouling, biofilm
Examples of biofouling, biofilm
(cont)
Examples of biofouling, biofilm
(cont)
Affection of biofoul & biofilm
Water quality: contamination by releasing micro-organisms
Health: release of pathogens in water
Hydrodynamic parameters: clogging, friction & hydraulic resistance
Material: covering surface, changing surface properties, enhancing microbial influenced-corrosion
EPS: house of the cells
Has a composition of extracellular polymeric substance: polysaccharides, proteins, nucleic acids, forming hydrogels (> 95% water) of microbial origin
Is an attachment of cells and of entire biofilm to surface
Is the cohesion in microbial aggregation
Is filling and forming the space between the cells, shape the threedimensional biofilm structure
Helps immobizing cells, allowing long-term syngenesis interactions
Step formation of biofilm
EPS and micro-organisms infection
Examples of biofouling, biofilm
Examples of biofouling, biofilm
Where are biofilms in water system
Mushroom model of biofilm
Mushroom model of biofilm
(cont)
Principles to reduce biofoul & biofilm
Nature of live: brewery has to learn to live with biofoul / bioflim and keep them under control – elimination of their affection
Detection: the growth of biofoul / biofilm and their affection
Defining detection parameters (cell/cm 2, CFU/cm2, biofilm thickness…), points, sampling points to monitor their growth, affection
Setting up a monitoring system: crucial for timely detection of biofilms and countermeasure optimization
Tolerance of biofoul/biofilm growth : applying risk management in terms of Haccp and product quality to set up max tolerance. Either:
Thickness of biofoul / biofilm
Micro-organism plate count on suitable media
Cleaning: is more important than killing biofilm organisms. Setting up a suitable cleaning regime with consideration of affection and cost
Prevention: where possible, biofilm management is done by nutrient limitation (nutrients are potential biomass)
Biofilm growth and threshold
Monitoring biofilm growth on time via quick testing method (ATP swab) or Onvida sensor
Pain Threshold is defined by user where the affection of biofoul, biofilm – pathogenic and product quality - is measurable
Method to detect & monitor biofilm
Killing vs Removal biofilm
Killing does not necessary to remove biomass, so dead biomass can still cause problems for process, product and health (head exchanger, membranes, process water…) Disinfection means inactivation of micro-organisms and this frequent job creates additional cost but not to sustainable solution
Chapter 3
C l ea ea n i n g & D is i s i n f e c t i o n p r i n c i p l es es
Source: HeiQ Paul Wood APB Microbiology Workshop Stijn Van Liefferinge, C&D Sopura SA DiverseyLever, Basic principle of CIP& Application John David Cluett, Cleanability of Stainless steel surface, Rank Afrikaans University, U SA
C l ea n i n g p r i n c i p l e s
What to clean: soil
To eliminate impurity of solution – called soil
To disinfect a surface effectively, elimination of soil must be completed first
Soil is any undesired matter on surface including product whether containing micro-organism or not
Sources of soil:
Residues of products (beer extracts, fats, lipids, proteins …)
Residues of water-soluble (salt, sugars) and acid-soluble products (calcium precipitates, dissolved inorganic)
Residues of water/acid-non-soluble (yeast)
Bio-film (bacteria, mould)
Residues / carry-over matters from cleaning and disinfection products
Contaminated by external environment (dust…)
Cleaning of soil - Function
Function of cleaning soil: is to remove/eliminate soil without leaving residues by either one or combination of actions:
Dissolving / emulsifying
Chemical reaction
Physical: mechanical, thermal
An effective cleaning of soil depends on soil’ characteristics, nature of surface and selection of
Right physical actions
Right cleaning product
Sufficient activity of cleaning product (concentration, activity level)
Right cleaning procedure (regime)
Right cleaning tools/equipment
Right process control conditions
Cleaning soil
Function: cleaning of soil is achieved by one / combination of energies:
Mechanical
Liquid rinsing flow (hl/h respective with designed flow Re)
Pressure flow impact (bar)
Brushing (kg/cm 2, frequency time/s), stirring (rpm)
Thermal: only effective when it goes with time and limited by machine component and economy reasons ( 0C)
Chemical
Removal of soil without leaving residues
Concentration, frequency and contact time (economy use)
Environmental impact
Affection
on material being cleaned (machine component, pipe…)
Time is combined with energy to have necessary cleaning but sometimes a waste and limited by product process flow
Cleaning product - Function
Function of soil cleaning is achieved by the help of a cleaning product or also called carrying-product
Without cleaning product, soil cannot be removed from surface/system
Function of cleaning product: is to
Set a complete and full contact between soil, surface and product by wetting, lowering surface tension
Eliminate adhesion of soil on surface by rinsing
Reduce soil’s gravity by dispersing soil in small particles
Carry soil particles in product till it is discharged to sewer by dissolving or emulsifying and suspending them - keep floating detached particles to prevent precipitation
Sequestering: eliminate / prevent the fall out water hardness salts
Cleaning products
Surfactants: makes a link between organic matter and water Anionic
Cationic
Non-ionic
Amphoteric
Wetting / Rinsing agent: reduces surface tension of water only
Dispersing agent: keeps removed soil in suspension – avoids the formation of soil floc
Sequestering agent: binds itself to something else Alkaline:
EDTA (Ethylene Diamine Tetra Acetic Acid) can dissolve scale – binding with calcium – and break it up when rinsing
Phosphonates
Na5P3O10
Gluconates
Cleaning products
Dissolving / Reaction agent Acids:
H2SO4
H3PO4
HNO3
Sulphamic acid
Organic acid like acetic acid
Alkaline:
Strong alkaline: caustic soda
Alkaline
salts:
Metalisicates,
Na3PO4
Na2CO3
Oxidization agent
Wetting & surface tension
Surface tension is the result of intermolecular attractive force which assures the cohesion of molecules
Both cleaning product and soil have surface tension
Water has high surface tension > bad wetting action Wetting and low surface tension
Wetting and low surface tension
No wetting and high surface tension
No wetting and high surface tension
Surfactants
Sequestrant
Physical form of soil
Physical form of soil on surface and its adhesion on surface
Loose, dry soil on surface:
Priority: mechanical (liquid flow)
Addition:
mechanical (pressure impact), thermal, chemical (dissolving / emulsifying)
Sticky soil in liquid or solid form (yeast stone, protein…):
Priority: mechanical (pressure impact, liquid flow) + chemical (reaction, dissolving/emulsifying)
Addition:
thermal
Solidified soil (dried yeast stone, beer/extract stone, scale…)
Priority: chemical (reaction, dissolving/emulsifying) + mechanical (liquid flow, pressure impact)
Addition:
thermal
Composition of soil
Composition of soil and removal method
Organic: containing carbon element in molecule Alkali
dissolvable organic matters like caustic soda in environment of non-CO2
gas Acid
Inorganic: not containing carbon element (Ca++, Mg++…) Acid
dissolvable organic matter like phosphoric acid
dissolvable inorganic matter
Combination of organic and inorganic
Practical soil in brewery
Practical soil in brewery
(cont)
Practical soil in brewery
(cont)
Practical soil in brewery
(cont)
Practical soil in brewery
(cont)
Practical soil in brewery
(cont)
Practical soil in brewery
(cont)
Practical soil in brewery
(cont)
Practical soil in brewery
(cont)
Nature of surface
Surface roughness is evaluated via parameter Ra (µm) – peak-tovalley height. The less the better. Stainless steel fermentation tank: Ra ≤ 0.8 µm
Other parameters: max R a, waviness Wt, total depth P t, spacing N r
Mechanical rinsing flow - pipeline
Fluid movement: Reynolds index
Reynolds index for pipeline: Re = ρ*r*v/n
ρ: density of chemical product (g/cm 3)
v: average flow velocity (cm/s)
r: pipe radius (cm)
n: dynamic viscosity of liquid (g/cm*s)
Flow during cleaning of pipe line at internal surface
Re < 2,000
: laminar flow
2,000 < Re < 3,000
: transition flow
Re > 3,000
: turbulent flow
Real turbulent flow starts only at Re > 10,000
Internal pipe surface and welding line are failure of Re
Mechanical rinsing flow – pipeline
(cont)
Rule of thumb for liquid flow respectively with Re > 3,000
Cold cleaning (ambient temperature): velocity >< pipe diameter
For pipe diameter ≤ 50 mm, a flow > 3.5 m/s must be reached
For pipe diameter > 50 ≤ 100 mm, a flow > 2 m/s must be reached
For pipe diameter > 100 mm, a flow > 1 m/s must be reached
Hot cleaning (80 – 850C): velocity 1 – 1.5 m/s is sufficient
Flow rate is calculated from pipe diameter and velocity
If velocity is lower than above, cleaning is not effective, i.e. presence of soil residues after cleaning
If velocity is higher than above, there is no improvement of cleaning but a risk of water hammer, damage to pipe work and fittings
If velocity is as above but soil residues are found at final rinse, look at effectiveness of other cleaning actions and energies
Mechanical rinsing flow – pipeline
Flow rate in liter per minute
(cont)
Mechanical rinsing flow - tank
Reynolds index for tank: Re = mF/n
mF: mass flow of medium film a meter tank width (circumference)
n: dynamic viscosity of liquid (g/cm*s)
Flow during cleaning internal surface of tank
Lamination film 200 < Re < 500
: 0.5 – 1.5 L/min/m 2
Turbulent film Re > 3,000
: 1.4 – 3.3 L/min/m 2
As experiment, at Re > 3000 and Ra = 0.8 stainless steel tank, the flow speed on internal tank surface is about 0.022 – 0.025 m/s
Extra mechanical effect: pulse dwell with fixed spay ball
Mechanical rinsing flow – Plate Heat Exchanger
Rule of thumb, cleaning of heat exchanger requires a detergent flow rate which is 20 – 30% higher than the product flow rate
For high soil content product like wort, cleaning rinsing flow of PHE is in reverse direction of product flow, i.e. cleaning product going from outlet of PHE to discharge at inlet of PHE
Mechanical flow pressure impact
Flow pressure impact is critical in cleaning of soil in tank. All tank cleanings are done by spray device system
Spray ball inlet flow pressure is very critical
Static spray head
: 1 – 2.5 bars
Rotary spray ball / disk
: 5 – 8 bars
Too little pressure: tank wall is not reached, less flow pressure impact to remove sticky/solidified soil, not enough rinsing flow for tank
Too high pressure: reduces effectiveness of rinsing flow
Thermal of cleaning flow
Temperature is defined according to
Cleaning product used (supplier spec)
Customer specification (machine, system, fittings, sealant…)
Soil’s characteristics
Material – surface to be cleaned
Not always higher temperature of cleaning fluid, lower cleaning time!!
D is i n f e c t i o n p r i n c i p l es
What to disinfect: micro-organisms
Function of disinfection: destroying of beer spoiling and not-beer spoiling micro-organisms to an acceptable level
Micro-organisms can be :
Pathogenic
Harmful
Troublesome
to health or to the quality of products
Bacterial spores are usually not killed and difficult to be killed
Micro-organisms are destroyed by one or combination of methods
Chemical disinfectants
Physical: UV, heat
Sterilization destroys all forms of live
Source of micro-infection
Source of contamination:
Production process Apparatus
having dead ends
Chinks, fittings, couplings
Surface, material, system cavities
Open vessels (air suction)
Residues from previous process
Pre-run / Post run…
CIP process
Contaminated final rinse water
Bio-film
Others
Man: flora from hand, breath, skin, clothes, production tools…
Insects, dust…
Disinfection
An effectiveness of disinfection depends on:
Type of micro-infection, i.e. micro-organism species
Level of micro-infection, i.e. number of micro-organisms
Type of disinfection method, e.g. disinfectants
Concentration of disinfection dose
Type and conditions of surface
Temperature
Movement of liquid
Type and amount of soil residues, dirts
Disinfectants
Selection of disinfectant is a consideration of:
Broad spectrum and biodegradability, especially spore forming
Minimum influence of at application conditions: pH, low temperature, presence of protein
Neutralization by CO2
Composition should not changed or reduced by carrier (ex water hardness)
Food and health safety: no smell, taste / colour or harmful to man
No influence on material / surface (ex: corrosion)
Easily rinse-able by water (ex residue after cleaning)
Environment friendly and local legal compliance
Technological useful (contact/exposure time, installation…)
Recoverable
Cost (i.e. consumption, price)
Disinfectants can be not stable at storage (both concentrated solution and working solution)
Disinfectants (cont)
Common disinfectants:
Chlorine (NaOCl and ClO2)
Iodophores
Halogenated acetic acid ester
Halogen carbon acid
Peroxydes
Gluteralhehyde
Quaternary ammonium compounds (QAC)
Amphoterics
Salicylates
Chapter 4
C l ea n i n g & D i s i n f e c t i o n S y s t e m & P r o c e d u r e (R eg i m e )
Source: HeiQ Stijn Van Liefferinge Sopura SA
Control and reduction of soil load
CIP is a cleaning system integrated into production process – can be manually controlled or completely automated
03 type of CIP programs:
Regular Cleaning and Disinfection (C&D)
Disinfection only
Occasional Cleaning & Disinfection
TPM 1st priority: Regular CIP program is set up and controlled for a “standard” soil load and micro-infection level and routes. It is effective when
Soil type and load level (thickness) is controlled (what and how much)
Soil deposited location is controlled (where)
CIP program conditions are controlled
TPM – 2nd priority: Less soil load is on surface and system, less cleaning activities (procedure) is required, i.e. lower cost, higher productivity
Control and reduction of soil
(cont)
Control Control of of soil load - examples examples
Scheduled inspection of tank before / after CIP
No violent fermentation, no overfoam at FST
Cleaning within time tolerance after emptying
Contamination of recovery cleaning chemical products…
Reduction Reduction of soil soil load - examples examples
Settlement and draining caustic in washer
Mess-filtration of caustic at washer
Pre-rinsing yeast harvest on pipe before CIP
Keeping system cleaned and dry for a period of stop time…
Soil development conditions are present and monitored so that occasional CIP is applied
Standard CIP – recovery & circulation
Standard CIP program – Functions of step
Pre-rinse: reducing of soil to a level where the designed CIP regime Pre-rinse: (procedure) is applied, normally by water rinse or recuperation caustic
Medium change: change: obtaining right conc of cleaning chemical, normally in CIP supply pipe
Rinse: eliminating soil by hot/cold caustic, acid agent is used in some Rinse: conditions (under CO2 pressure…)
Intermediate rinse: rinse : recuperating and reducing conc of cleaning chemical to an acceptable level
Medium change: change: obtaining right conc of disinfection chemical, normally in CIP supply pipe
Disinfection:: destroying micro-organisms Disinfection
Medium change: change: recuperating and reducing conc of disinfectant to an acceptable level
Final rinse: rinse: eliminating disinfectant residues before re-using by disinfected water
Example of a CIP program
Object Group 2
InFlow
Steps
OutFlow/Recup. Parameters
s p e t S
T
Strength
Duration
Rest
Pulses
1% w/v
1 min
10 min
4
1 min
2 min
3
3 min
1 min
8
1 min
2 min
2
Fermenter (Vertical)
1
Fresh
Caustic pulses
to drain
Ambient
Fermenting and/or Storage Tank
2
Recup
Water rinse
to drain
Ambient
Rest Beer Tank
3
Recup
Acid circulation
Unfiltered Beer Buffer Tank
4
Recup
Water rinse
(W aste Yeas t T ank , see rem ark s)
5
Recup
Disinf ec tant c irc ulat ion
to Group 1 and 2 Am bient by s upplier
3 min
1 min
8
Foam catcher
6
Fresh
Water rinse
to Group 1 and 2 Ambient
1 min
2 min
4
to Group 1 and 2 Ambient by supplier to drain
Ambient
Conditions of CIP: run & change steps
Pre-rinse: one / combination of either some or all
Soil load (thickness): visual assessment before and after pre-rinsing – majority of sticky soil
Circle count: pre-rinsing volume and total volume of all ci rcles; Or: pre-rinsing time / circle and total time of all circles
Circle ends: Empty signal if applicable (LAL)
Number of circles
Pressure of flow on CIP supply pipe (after pump) or pipe head to spray ball
Flow rate of CIP supply pipe (after pump)
Medium change to rinse: one / combination of either some or all
Concentration / conductivity at pipe head to spray ball or sometimes at r eturn pipe to drain
Medium volume at desired point
Time to reach the concentration / conductivity
Opening time of draining valve
Conditions of CIP: run & change steps (cont)
Rinse: one / combination of either some or all
Soil load at final rinse: visual assessment (color), chamber count of soil (soil density), identification of soil
Circle starts: temperature, conc/conductivity = designed value
Hot cleaning: temperature after PHE, temperature at return pipe (recovery)
Conc/cond at pipe head to spray ball (rinse t o drain) or at return pipe to drain (recovery)
Circle count: pre-rinsing volume and total volume of all circles; Or: pre-rinsing time / circle and total time of all circles
Circle ends: Empty signal if applicable (LAL)
Number of circles
Spray ball: pulse and pause duration
CIP return pump: run / stop duration
Pressure of flow on CIP supply pipe (after pump) or pipe head to spray ball
Flow rate of CIP supply pipe (after pump)
Chemical contamination load after rinse (COD, turbidity, EBC, UV A rate): recovery system
…
Conditions of CIP: run & change steps (cont)
Final rinse: one / combination of either some or all
Micro-infection: ATP swab, micro analysis of final rinsing sample
Disinfectants/cleaning product infection: smell, concentration, indicator (phenolphthalein)
Circle count: pre-rinsing volume and total volume of all circles; Or: prerinsing time / circle and total time of all circles
Circle ends: Empty signal if applicable (LAL)
Number of circles
Spray ball: pulse and pause duration
CIP return pump: run / stop duration
Pressure of flow on CIP supply pipe (after pump) or pipe head to spray ball
Flow rate of CIP supply pipe (after pump)
…
Volume for a CIP circle
Sufficient fill volume for a C&D circle is important for an effective CIP: cleaning flow and sometimes soaking
Cleaning product and water consumption is made up on a given CIP route
A fill volume is about 1.3 calculated volume of pipe route + volume of chemical thickness on vessel surface (1.5 – 3.5 L/m2)
Chapter 5
C le an i n g & D i s i n f ec t i o n A g en t s
Source: HeiQ Stijn Van Liefferinge Sopura SA Paul Wood APB Microbiology workshop DiverseyLever, Basic principle of CI P& Application
Selection of cleaning products
Factors affecting selection of cleaning products
Nature of soil
Nature of material of unit / system (surface, type of steel, heat stability…)
Hardness of material
Temperature
Cleaning method, procedure
CIP equipment / system
Possible danger of product – man safety
Influence on product – food safety
Biological degradability – environment
Cost
Application properties of cleaning product
Some chemical products ex Sopura
ATR B
Based on phosphoric acid combined with non-foaming non-ionic biodegradable surfactants
Removal yeast deposit and beer stone on vessel surface under CO2 pressure condition
Caustic Purexol:
Based on sequestrants + KOH + 3g chlorine / 100 g product
Alkaline
chlorinated detergent for the simultaneous deep cleaning and sanitation – removal sticky and organic scale (solidified) on surface
Normal application frequency: once 12 – 18 months
Septacid S
Based on sulphuric acid, bromacetic acid and corrosion inhibitors
Simultaneous cleaning and sanitation with strong bacteriocidal actions on yeast, both gram positive and negative bacteria
Chapter 6
S p r a y h e ad s
Source: DiverseyLever, Basic principle of CI P& Application Sani-matic spray ball Toftejorg high pressure impact Rotary Jet Head
Static spray head
Static / fixed spray head:
2 types: spray ball and spray disk
Operation pressure: normally low pressure: 1 – 2 bar
Key parameters of spray ball should obtain to get effective cleaning:
Specific flow rate
Pressure and pressure curves
Connection inner and outer diameter
Spray ball types: 360 0, 1800 upward, 180 0 downward, 180 0 directional bias shot, 2700 upward, 1200 upward
Choice of spray ball types depends on:
Distance of device from walls of tank
Depth of installation
Tank dimension
Type of cleaning product used
Tank use
pump specification
Guide line for spray ball
3600: applied for heavily soil or tank with internal devices
1800 upward spray: cleaning top of tank, lower half of tank will be cleaned from the fluid running down side
1800 down spray: cleaning specific internal instrument or other items that interfere with cleaning used downstream spraying ball
2700 upward spray: covering more surface and allow direct cleaning (pressure impact of cleaning product) of more heavily soiled areas, specially top tank dome, yeast ring.
Bottom center of tank may have outlet valves or other fixtures that do not require direct exposure to cleaning unit
Static spray head – pattern
Static spray head – pattern (cont)
Static spray head – parameters
Static spay ball – Installation depth
High pressure rotary spray head
High pressure rotary spray head
High pressure: 5 – 8 bar
Impact throw length is 5 – 15 meter
Rotary Jet head provides 3600 indexed impact cleaning over a defined period
Working principle: flow of fluid makes nozzles performs a gear rotation around vertical and horizontal axes. Normally, 1 st cycle nozzle lay out a coarse pattern on tank surface. A full pattern is reached after 8 cycles
Choice depends on desired jet impact length and flow rate at desired pressure
Rotary spray head – pressure curve
Pressure loss at spray head
To obtain sufficient pressure at spray ball, pressure at cleaning pump must be compensated for hydraulic pressure loss (mainly) and other losses (friction, fittings, bend…)
Chapter 7
H y g i e n e Re q u i r e m e n t s a n d S t an d a r d s
Source:
Heinek en Hygienic D es ign Manual (HeiQ) DiverseyLever, Basic principle of CI P& Application Martin Hees, Industry Marketing Food
What is hygiene?
Hygiene is
Compliance with all conditions
During design & use of process equipment
To achieve the greatest possible suitability of process
For the purpose to guarantee the highest possible safety for customer of the product
Functions of hygiene are
Clean-ability of equipment: easily to clean, disinfect protect product from contamination
Avoidance
of penetration of micro-organism from external to system
Inhibition of micro-organism growth in equipment: like dead-ends, gaps, cracks, bio-film
Suitability of process in compromising hygiene compliance and other equipment functional requirements (ex OPI)
Hygiene zone
Zone B: basic level of hygienic design and maintenance for open areas like outside buildings, walking way, canteen…
Zone M: medium level of hygienic design and maintenance to protect the interior of food processing equipment during closed processes like fermentation, filtration…
Zone H: high level of hygienic design and maintenance to protect product contamination during open processing like culturing / propagation, filling from environment and exterior of equipment
What hygiene practices
Hygienic standards should be set for
Suitable selection of equipment and design
Materials and accessories for C&D (ex smooth, no crevices, pits, edges, blind ends)
Correct construction
Process layout (ex cross contamination)
Process automation of the installation
Effective cleaning is difficult to check but a few below method is used:
Visual inspection before and after cleaning
Water break test (no drops on clean surface)
ATP-free
swap test
ATP bio-luminescence
ATP is a molecule found in living organisms – a main immediate source of usable energy for all activities of cell
Enzymes called Luciferases that emit light and when ATP is brought into contact with a combination Luciferin Luciferase, a reaction is taken place, resulting in production of light from release of Luciferase
The higher contamination, the more ATP present and more light is produced
ATP-free swab
ATP is practically used to evaluate the effective cleaning level instead of waiting for 3 – 5 days period where incubation of samples required How ATP-free swab test works: ATP
swabs are pre-moistened with agents that help to lift soil off surface
After
taking sample with the swab, it pushes into tube, is shaken and finally into illuminometer
Clean sample gives low light level
Dirty level gives high light level. The measure is made in RLU (Relative Light Unit)
Normally RLU > 100, the surface is not hygiene
Application areas of ATP in a brewery
Application areas of ATP in a brewery (cont)
ATP test example in a brewery
Hygiene in piping, fittings, connections
Hygiene in piping, fittings, connections (cont)
Hygiene in piping, fittings, connections (cont)
Hygiene in piping, fittings, connections (cont)
Hygiene in piping, fittings, connections (cont)
Hygiene in piping, fittings, connections (cont)
Hygiene in piping, fittings, connections (cont)
Hygiene in piping, fittings, connections (cont)
Hygiene in product contact surface
Hygiene in product contact surface (cont)
Hygiene in product contact surface (cont)
Hygiene in accessories
(cont)
Hygiene in accessories
(cont)
Hygiene in accessories
(cont)
Hygiene in accessories
(cont)
Hygiene in process equipment
(cont)
Hygiene in process equipment
(cont)
Hygiene in process equipment
(cont)
Hygiene in process equipment
(cont)
Hygiene in process equipment
(cont)
Hygiene in fittings, connections
Hygienic standards - others
Other hygienic standards are reference in Heineken Hygienic Design Manual for:
Materials: plastic, elastics, adhesives, stainless steel…
Piping system, tees, flanges, gasket, coupling, hosing,
Valves
Other accessories
Heat exchanger
Pump
Process equipment: spray ball, drive shaft and bearing,
Hygiene standards for high risk local machine cleaning is set up by brewery
Haccp (Iso 22000) requires food safety risk analysis, pre-requisitition program and verification of risks and control plan
Hygiene audit
After standards available, Hygiene is maintained by schedule Hygiene Audit by qualified staff Hygiene Audit is a mandatory requirement of brewery operation
Chapter 8
D i s i n f ec t i o n b y U V L i g h t
Source:
UV Wikipedia encyclopedia American Water Works Association
UV Light Application
UV-C 265 nm is germicidal, (1) di-merizes on ADN and inhibits bacteria to replicate molecule ADN, (2) produces a condense ozone environment (air)
Germicidal effectiveness is depended type of bacteria and UV dosage (Ws/m2) at the application point
Each bacterium has different UV resistance: protozoan cyst > bacteria spore > viruses > vegetative bacteria
UV dosage = UV intensity W/cm2 * Exposure time t (seconds)
UV intensity = UV intensity of Lamps * number of Lamps * Intensity Factor / Transmission Loss
UV Intensity
In air, UV transmission = 100% at a distance of 1 meter to application point. The closer the stronger and vice versa (table)
In distilled purifying water, UV transmission = 100% at a distance of 10 mm to application point
UV intensity sensor provides only means of ensuring that adequate disinfection
Ex: 04 lamps of 66 W/m2 each, reactor: 70 L, water flow: 320 L/min, T10 = 0.95
Conditions of UV transmission
Water quality factors
Shielding caused by suspension solids
UV light scattering by colloidal solids
UV absorbance by dissolved organics (w
Quartz sleeve foul by inorganic constituents (Ca, Mg, Al, Fe, Mn,
Quartz sleeve transmission ability (colorization of quartz over time)
Water quality (color, air bubble, other factors affecting transmission)
UV lamp low-pressure (LP)
Giving optimum germicidal wave length 260 nm – monochromatic
Optimum lamp operating temperature
Lamp age and spectral shift
Conditions of UV transmission
Reactor
Internal chamber surface reflecting capability
UV dose delivered is path-dependent
UV sensor
Number of sensors and placing them at optimum positions
Routine check with reference sensor
Factory check to control linearity and drifting
Sensor window cleaning
UV Reactor monitoring
As the minimum
UV intensity by sensor
Water flow rate
Lamp outage
In addition
Water turbidity
Quartz foul
Start-up / out-specification operation / shut-down
Chapter 9
Q N et i n m i c r o -i n f e c t io n i n v e s t ig a t i o n & p r o b l e m s o l v i n g
Setting up a QNet
Only setting up a QNet when reoccurrence of micro-infection is high and daily solution does not give sustainable improvement
Steps to build up QNet and investigation of micro-infection
Identifying process flow and machine boundary (the closed product source of supply) related to the detection point of product micro-infection – normally P&I is used
Identifying all product inflows, outflows to external extents of t he machine boundary – P&I and/or site check
Identifying all product internal flows in machine boundary – P&I and site check
Identifying, marking all machine components in the boundary and defining their functions
Defining possible soil sources of soil and soil characteristics on each machine component
Defining possible sources of micro-infection, if necessary extra detection point is installed, at each machine component
Hygiene and CILT audit on site to check for compliance – at least 3 times at different moment. The more auditing times, the more problem is found because of more opportunities to catch abnormally
Restoring basic conditions according to Hygiene requirements
Setting up a QNet
(cont)
Steps to build up QNet and investigation of micro-infection
(cont)
Defining reverse clockwise activities of a full cycle (repeat activity) and flow routes of each product flow machine component.
Check generation points (of soil, infection according to above identification), detection point and control points of all cycles. Make correct ion or improvement
Check if the micro-infection is eliminated
If not, repeat the s ame steps to the upstream (inflow) process flow/machine boundary and downstream (outflow) process flow / machine boundary
Defining also the reverse clockwise activities of new process flows/machines, sources of soil/contamination, generation point, detection point and control point. Make correction or improvement
Update new control point and condition in QM for tr aining, monitoring…
Setting up a QNet
Internal flow Function: CIP to spray ball
(cont)
Product buffer tank system
Detection point
Product inflow Function: Product supply Product inflow Function: CIP supply
Product outflow Function: product discharge
Product outflow Function: overflow from filling
Setting up a QNet
Product inflow Function: Water supply
CIP system
Water
Product inflow Function: CIP supply
(cont)
New detection point
Caustic Product outflow Functi Function: on: CIP supply to Buffer tank
Product outflow Function: overflow from filling
Setting up a QNet
(cont)
Weekly cleaning Pre-rinsing Caustic medium change
e l c y c w o l f s s e c o r p k n a t r e f f u B
Level making-up
New generation point
Supplying fresh water at 30% tank level to 80% Waiting
Caustic rinsing
Supplying water till level drops to 30%
Post rinsing water Product buffering
Level making-up
Flushing in tank, pipe Filling and supplying Emptying Sterilization
New detection point
Pre-rinsing Sterilizing Cooling (fresh water) Waiting (time) Product buffering Flushing in tank Filling and supplying Emptying Weekly cleaning
Detection point
e l k c n y a c t r w e l o t a f w s s h e s c e r o r F p
