Beer Stability - Knudsen Beverage Consulting
Download
Report
Transcript Beer Stability - Knudsen Beverage Consulting
Novel Options for Stabilization of Beer
Mustafa Rehmanji
Ashland Inc.
1005 Route 202/206
Bridgewater, NJ 08807
Scope of Presentation
• Why should you Stabilize your Beer ?
• Implications of Colloidal Stability
• Mechanism of Haze Formation
• Option for Upstream Stabilization with Polyclar
Brewbrite
• Combined Stabilization with Polyclar Plus 730
Drivers for Beer Stabilization
• Consumer expectations for better quality and product
consistency
• Expanded distribution areas: Beer travelling farther
from the brewery
• Challenge of producing quality products in developing
markets to compete with imports
• Need to reduce costs – production, return of beers
Beer Haze Stability Definition
• Development of Haze in Beer – The
colloidal stability of beer is a function of time
and temperature.
• The end of useful shelf life of beer is defined
in terms of haze.
• Total Haze of 2.0 EBC units is usually taken as
the end of shelf life
Beer Storage and Transport
8
7
EBC
6
Store 0 C
5
Store 40 C
4
Haze
Cycled
3
Shaken 40 C
2
1
0
Treatments
Data courtesy Brewing Research Institute, UK.
Model of Haze Formation
Tannoids
Simple
Flavanoids
Protein
Oxidized
Flavanoids
No haze formation
Protein
Chill haze
Protein
Permanent haze
Model for Protein – Polyphenol
Interaction
Polyphenols are depicted as having two ends that can bind to protein. Proteins
are depicted as having a fixed number of polyphenol binding sites.
polypeptide
Proline-rich region
polyphenol
Courtesy : Karl Siebert, Cornell University
Formation of Protein-Polyphenol Haze in Beverages, J. Agric. Food Chem. 1996,44, 1997-2005
Relative Haze Formation
Beer stabilized with 100 g/hl PVPP to remove
reactive polyphenols
Catechin Haze EBC
Tannic Haze EBC
Oxidized Catechin
2.4
30
Catechin
2.2
25
Oxidized Catechin
2
20
Tannic acid
1.8
1.6
1.4
1.2
1
0.8
15
10
5
0
10
20
30
40
Addition rate of reactive polyphenols in g/hl
50
0
Flavanoids & Tannoids in Beer
Shelf Life Model
Compare with PRIOR SLIDE
Haze-active Polyphenols & Proteins
Beer Model
Balanced “As Needed” Stabilization
Sensitive
Proteins
Tannoids
3 months
5-9months
Flavanols
9-12months
Non-haze
active
proteins
Proteins
Non-haze
active
polyphenols
Polyphenols
Raw Material & Process Strategies to
Optimize Colloidal Stability
Process
Polyphenol Reduction Protein Reduction
Process Optimization
Raw material
selection
Low proanthocyanidin
malt
Hop extract
Low protein
barley
Low malt modification
Brewhouse
High adjunct ratio
Mashing process
pH, temperature
Vigorous kettle boil for
>60 min.
Avoid weak worts
Good hot break
Coarse grind of malt
Avoid excess mineral
salts
Cold wort filtration
Fermentation/
Maturation
Filtration
Rapid onset to
fermentation
Early yeast
removal
Minimum 7 days
maturation at -1OC
Low solids count
Filter at -1OC
Avoid O 2 Pick up
Admixture of Kappa-Carrageenan and micronized
PVPP- Polyclar Brewbrite
Kappa Carrageenan
OSO-
CH OH
3
2
O
O
O
PVPP
CH
2
O
N
O
O
N
O
N
O
O
OH
OH
n
ß-D-galactose 4 sulfate 3,6-anhydro-α-D-galactose
Marine polysaccharide of
galactose & galactose sulfate
monomers
n
2-pyrrolidinone,1-ethenyl-, homopolymer
Cross-linked
polyvinylpyrollidone
Function/Purpose
The addition of Admixture of Carrageenan/PVPP
to the boiling wort has the following functions:
• To stimulate coagulation of the proteinaceous
particulates
• To promote the cohesion of the coagulated
protein particles and of other proteincarbohydrate complexes into bigger flocs which
can settle to the bottom of the tank faster
(whirlpool), or are more effectively removed by a
mash filter
• To facilitate upstream adsorption of polyphenols,
particularly, TANNOIDS from the wort
Courtesy of Murphy-Savilles Clarification
Effect of Cold Wort Clarity on Beer Clarity
Bright 3
(<3 EBC)
Hazy 2
Clarity (>4 EBC)
Rating
Cloudy 1
(>8 EBC)
0
0.7
1.4
Filtered Beer Haze (EBC)
wort clarity is very important and is
related to beer clarity
2.1
Increase in Wort Yield - Commercial Trial
Brewbrite gave 3.2% increase in cold wort collected in FV as
compared to untreated wort
Volume of Wort at collection, hl
Also, Brewbrite gave a higher throughput on the centrifuge
and longer filter run lengths
16.1
16.0
15.9
15.8
15.7
15.6
15.5
15.4
15.3
15.2
Untreated
Carrageenan,
alone 3.9g/hl
Brewbrite
15g/hl
Decrease in Fermentation Time –
Commercial Trial
Brewbrite gave 10 % reduction in
fermentation time as compared to untreated
145
140
135
130
125
120
Untreated
Carrageenan alone,
3.9g/hl
Admixture
15g/hl
Analysis of Packaged Beer - Commercial Trial
Accelerated Forcing Test
Total Haze, EBC Units
3.5
3.0
Admixture
2.5
15g/hl
2.0
1.5
Untreated
1.0
0.5
0.0
Initial
Cycle 1
Cycle 2
Cycle 3
Cycle 4
Cycle 5
Cycle = 24 hours at 600C followed by 24 hours at 00C
No. of Cycles (to reach 2.0 EBC Units) = month of predicted shelf life
Trial A
Malt- Adjunct Lager
Control Beers
• Average cold wort
collection = 501 hl
Brewbrite Trial Beers
• Average cold wort
collection = 506 hl
(+1% volume)
• Wort clarity = 4.3 EBC
• Total haze at end of
shelf life = 7.1 EBC
• Wort clarity = 1.2 EBC
• Total haze at end of
shelf life = 4.5 EBC
Trial B – All Malt Lager
Dosage Evaluation
120
35
Optimum
Addition
Range
30
25
80
20
60
15
40
10
20
5
0
0
0
5
10
15
20
Brewbrite Addition Rate (g/hl)
Tannoids (mg/l)
Wort Clarity (EBC)
25
30
Wort Clarity (EBC)
Tannoids (mg/l)
100
Dosage Evaluation-Trial B
Trial-B
100% Malt Lager
Polyphenol Reduction
400
350
Total Polyphenol reduction = 21%
300
mg/l
250
200
150
100
Tannoid reduction = 49%
50
0
Pre-addition
Post addition
Sample Stage
Tannoids
Total Polyphenols
South America Brewery Trials
Brewery
A
Wort Yield
(%)
+2
B
+2
C
0
Beer Stability
Slight increase
Similar to 40 g/hl
SHG + wort
stabiliser
Similar to 60 g/hl
SHG + papain
Will the Materials Segregate?
110
100
90
80
70
60
Sample as is
50
40
Segregation BEGIN
30
Segregation MIDDLE
20
Segregation END
10
0
0
25
50
75
100
125
150
Particle Size in m
The potential for Polyclar Brewbrite to
segregate due to a sifting mechanism is low
Summary of Trial Results
Enhances clarity of wort & beer
Increases wort production
Decreases fermentation time
Improves total productivity of plant
Extends shelf life of packaged beer
Longer shelf life requires PVPP treatment at
filtration
PVPP helps reduce astringency in beer*
* Measuring Astringency of Beverages using a Quartz-Crystal Microbalance
J.Am.Soc. Brew. Chem. 61(3):119-124, 2003
A composite of micronized
Polyvinylpolypyrrolidone (PVPP) and
selected Silica Xerogel- Polyclar® Plus 730
Key Features
Optimized ratio for preventing chill
and permanent haze
High adsorptive capacity for hazeforming precursors
Improved handling and performance
characteristics
Re-dispersion PVPP/Silica Admixture
Greater than 2000
80
57
PVPP
Xerogel
PVPP/Silica
Admixture
Inversions required to re-disperse 10%
slurries after 24 hours of sedimentation
Improved dispersion results in a more homogeneous dosing into the beer
Possible Injection Points
DE
Stabilizer
Inlet
Buffer
Tank
To
Packaging
DE Filter
Buffer
Tank
Dosing
Tank
Bright
Beer
Tank
Trap/Bag
Filter
Polish Filter
Cycles to 2 EBC (Warm Days)
60°C/24 hr. - 0°/24 hr.
Forced Haze Development in Packaged
Beer - Trial A
10
8
6
4
2
0
Si hydrogel
95 g/hl
Si hydrogel
95 g/hl
+ PVPP
20 g/hl
Admixture
PVPP/Silica
xerogel
40 g/hl
Admixture
PVPP/Silica
xerogel
60 g/hl
Admixture
PVPP/Silica
xerogel
80 g/hl
US Microbrewery Trial B
200 bbl of American lager treated
Stabilizer dosed in-line, before buffer
tank
Dosage rate of PVPP/silica xerogel
admixture - 10 lb/100 bbl (38.5 g/hl)
Increasing Protein Stability ==>
(ml P40/100 ml Beer to 5 EBC Additional Haze
Trial B Stabilization Results
PVPP/Silica Xerogel Admixture
Predicted Shelf-Life in Months
100
90
5
80
70
4
60
Stabilized - 10 lb/100 bbl
50
40
3
2
30
20
Unstabilized Region
10
1
0
0
0
10 20 30 40 50 60 70 80 90 100
Untreated
Admixture
I week @ 370C with total haze @ 2 EBC
Increasing Polyphenol Stability ==>
is equivalent to I month of shelf-life
(ml T125/100 ml Beer to 2 EBC Additional Haze
Ale Stabilization- 2 Stage : Trial C
Objective to increase product shelf life
Normal regime - silica hydrogel on transfer to MV &
PVPP at filtration
Admixture of PVPP/Silica Xerogel (40 g/hl) dosed
on transfer from FV to MV (900 hl)
Beer cold stored for 7 days
PVPP (20 g/hl) added with DE body-feed - very
short contact time
~3 min.
Ale Stabilization- 2 Stage : Trial C
T125 & P40 - high values indicate better stabilization
Tannoids
(mg/l)
T125 Polyphenols
(ml/100ml)
P 40 Proteins
(ml/100ml)
FV
MV
BBT
35.0
<12
<12
11.9
55.0
123.0
21.2
49.4
51.6
Admixture PVPP/Silica Xerogel (40 g/hl)
PVPP (20 g/hl)
• Stage 1 - complete tannoid removal & substantial
protein and flavanoid reduction
•Stage 2 - further flavanoid reduction
Brewery Trials – Filter Pressures, Run Lengths
& Beer Stability
Dose rate
g/hl
P/hr*
Filter Run Time
(hr.)
Total Haze**
(EBC)
Xerogel only
35.8
0.49
6.4
6.9
PVPP only
12.6
0.35
7.4
3.6
Admixture
PVPP/Silica
Xerogel
33.0
0.25
12.0
1.2
Stabilizer
*Pressure increase at steady state
**Total haze measured at 0oC after 5 days
incubation at 60oC