Market Trends and Opportunities for Beverage Industry

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					Flavoring Beverages:
Opportunities and Challenges




                                                   October
              Andrew G. Lynch, Ph.D.
              Quest International
              Global Citrus Applications Manager
                                                   2005
              andrew.lynch@questintl.com
  What is Food Science ?
Food Science deals with the physical, chemical and biological
properties of food. Food Scientists are concerned with:


Nutrition and Safety
Stability
Processing and Packaging
Cost and Quality


There are very few things as personal as food!
flavoring   beverages

            •background

            •opportunities

            •challenges

               •citrus flavor stability
               •orange juice processing
               •clouds
               •milk & coffee drinks
Quest for   creative difference

               key facts

                  • creative leader in the industry
                  • corporate headquarters in Naarden, the
                    Netherlands
                  • two businesses: Flavours and Fragrances
                  • total sales US$ 1.1 billion (2003)
                  • creative and application centres and production
                    facilities across Europe, the Americas and Asia
                    Pacific
                  • approx. 3,500 employees
Quest for   creative difference
sales 2003: US$ 1.1 billion
                                  60% flavours



                 40% fragrances
flavoring   beverages

            •background

            •opportunities

            •challenges

               •citrus flavor stability
               •orange juice processing
               •clouds
               •milk & coffee drinks
opportunities - North American beverage market
                                                                                              Projected
          Sales 2003 ($ billion)                                                        CAGR (04-07)
                                                                                                          22.5
     38
                                                                                                          20.0
     34
                                                                                                          17.5
     30
                                                                                                          15.0
     26
                                                                                                          12.5
     24
                                                                                                          10.0
     20
                                                                                                          7.5
     16
                                                                                                          5.0
     12
                                                                                                          2.5
     8                                                                                                    0.0

     4                                                                                                    - 2.5

     0                                                                                                    - 5.0
           Carbonates     Still    Flavored    Flavored    Juices     RtD Tea,    Powder     Sports &
                         Drinks    Alcoholic    Bottled   & Nectars    & RtD     Beverages    Energy
                                   Beverages    Water                  Coffee                 Drinks
opportunities
market trends


           diet (low carbohydrate, low calorie)

           healthy fats (shift from trans and hydrogenated fats)

           shift from fanciful to more exotic natural flavor
            e.g. Blood orange instead of orange
           masking, suppressing & smoothing

           innovative beverages
opportunities
non-alcoholic beverage segment new launch top flavors 2004

     citrus flavors top the list, moving strawberry from #1 2003 to #3
           in 2004. cranberry and chocolate are new to the list.

           1.    lemon
           2.    orange
           3.    strawberry
           4.    chocolate
           5.    apple
           6.    peach
           7.    mango
           8.    raspberry
           9.    vanilla
           10.   cranberry

                 Source: Global New Products Database (Mintel)
opportunities
obesity




                                                       Obesity in the US is truly an
                                                      epidemic. In the last 10 years,
                                                     obesity rates have increased by
                                                      more than 60% among adults.




                            percent

                Source: World Health Organization 2003
opportunities
masking and suppressing




        • bitterness
          (soy, grapefruit, protein drinks, coffee)
        • sourness
          (coffee, fermented and acid products)
        • saltiness
          (iso-tonic applications)
        • artificial sweetener
          (low cal products, lingering aftertaste, lack of body)
opportunities
enhancement



                •   sweetness
                    sugar flavors
                •   aromatics beyond drinking
                    odor release prior to consumption, instant
                       teas & coffees
                •   visual
                •   taste modification
opportunities
innovation in beverages




        • dairy-based beverages
        • soy and juice combination drinks
        • meal replacement (juice/cereal/yogurt)
flavoring   beverages

            •background

            •opportunities

            •challenges

               •citrus flavor stability
               •orange juice processing
               •clouds
               •milk & coffee drinks
challenges

    •   packaging
    •   regulatory
    •   consistent quality of natural ingredients
    •   stability
        • processing
        • flavor stability
        • physico-chemical stability
challenges
regulatory


         • GMO

         • natural & artificial

         • kosher
         • nature identical

         • global customers

         • globalization of flavors
         • Halal

         • TTB (formerly BATF)
challenges
consistent quality of natural ingredients




         • natural products have natural variation
         • focused quality assurance program is critical
         • catastrophe in one part of the world? Example: 2004 Florida
           hurricanes significantly damage grapefruit crop
challenges
processing



        • consistency in scale-up & transfer to other regions
        • processing impact on flavor/cloud
              hot fill vs. cold fill

              oxygen control
challenges
flavor degeneration




        • fading

        • light induced degradation
        • acid hydrolysis

        • oxidation
flavoring   beverages

            •background

            •opportunities

            •challenges

               •citrus flavor stability
               •orange juice processing
               •clouds
               •milk & coffee drinks
challenges
citrus flavor stability




          • oxidation of terpenes

          • citral in aqueous low pH
          • acid catalyzed hydrations




           Source: Rouseff, R. and Naim, M. 2000. Citrus Flavor Stability. In: Flavor
           Chemistry, ed. By Risch, S.J and Ho, C.T. American Chemical Society. Pages
           101-121.
challenges
citrus stability demonstration



         soda base
               pH 2.7
               Brix 10.6
               Carbonation 7 g/L
               Good oxygen control

         storage conditions
               2 weeks at 4°C and 2 weeks at 45 °C
challenges
typical off flavor formation in acidic aqueous solution
challenges
off flavor formation in lemonade stored at high ambient temperatures
challenges
sensory analysis of aged lemonades

              bitter                   deteriorated

              3.5
                    3
                        2.5
                           2
                          1.5
                             1   0.5
 barny                            0                   moldy


                                                          Control 4°C
                                                          Control 45°C



             metallic                  oxidized
challenges
lemon flavors


                     less off flavors
                     increased shelf life




                      traditional citrus favorites
   citrus flavors that deliver

           with authentic taste profiles
flavoring   beverages

            •background

            •opportunities

            •challenges

               •citrus flavor stability
               •orange juice processing
               •clouds
               •milk & coffee drinks
Orange Juice Processing

    •   Oranges are processed to make not from concentrate
        (NFC) or frozen concentrated orange juice (FCOJ)

    •   Quality must be controlled (variety, growing conditions, etc)

    •   Processing must be closely controlled to:
        •   Deactivate enzymes
        •   Limit oxygen levels
        •   Destroy pathogenic and spoilage microorganisms
        •   Minimize chemical and flavor changes

    •   Correct packaging and storage conditions must be used to
        deliver safe and stable product to consumers.
Cross section of Orange

                     Juice vesicles




                              Flavedo

                                 Albedo




                                Oil glands
Citrus Materials: Basic Processing
Overview of Production of Orange Juice Concentrate

             Main Products                               By-Products



        Fruit Reception     Juice Extraction              Peel Oil Recovery
                              Clarification
                                                             Peel Oil
                Pasteurization           Past/Evaporat

                      NFC                      OJFC


                            Bulk Transportation
                                                          Essence Recovery
                              Reprocessing
                                                          Oil Phase
                                 Packaging                Water-Phase Aroma
                               Distribution

                                                            Pulp, Limonene,
                                                           Citrus Pulp Pellets
Why does juice need to be pasteurized ?
 (1) Enzyme deactivation

 •   Deactivation of pectin methyl esterase (PME)

     •   PME cleaves methyl groups from pectin causing cloud loss and gelation
     •   Calcium (from the juice) interacts with the demethylated pectin
     •   Calcium pectate is insoluble and settles at the base of the container



 •   For Florida-grown Valencia oranges, a heat load of 2-3 D values is
     generally sufficient for total enzyme destruction.

     •   Typically pasteurization conditions employed are 95-98C for 10-30 secs.
    Why does juice need to be pasteurized ?
        (2) Ensure a microbiologically stable product



•   Main micro-organisms of interest in OJ are:
    •   Acid-tolerant bacteria, yeasts and moulds


•   Acid-tolerant bacteria, e.g., Lactobacillus plantarum (grow best at 20-37C)
    •   Spoilage characterized by diacetyl (buttery) off-notes and CO2


•   Saccharomyces cerevisiae is the most common spoilage microorganism
    •   Spoilage characterized by alcoholic fermentation, off-flavors and CO2

•   Spore-forming microorganisms (thermo-resistant acidophilic bacteria)
    •   In 1992, Alicyclobacillus classified as new genus
    •   Spoilage characterized by an off-flavor like “disinfectant” or guaicol
    Thermal processing of OJ

•   Thermal resistance of microorganisms is traditionally expressed in terms
    of D values and Z values.



•   D value is the time at a specified temperature for the microbial population
    to decrease by 90% or one log cycle (also called the decimal reduction time)



•   Z value is the change in temperature needed to alter the D value by
    one log cycle
    •  For example, if an organism has a z = 10C and a D80C = 1 min,
    then the D90C = 0.1 min and the D70C = 10 min.
Thermal processing of OJ

•   Pasteurization destroys most vegetative microorganisms but has little effect
    on bacterial spores (Most spores do not grow < pH 4.5).

    •   long term survival of some pathogens in unpasteurized refrigerated juice is
        possible, therefore pasteurization is recommended



•   For microorganisms usually found in fruit juices, z values are typically 5-7.
    •   Typical pasteurization temperatures are 75-95C for 15 to 30 secs


•   For a given increase in temperature, the rate of destruction of microorganisms and
    enzymes increases faster than the rate of destruction of sensory and nutrient
    components.


•   Summary……Deactivate enzymes, Ensure microbiological safety and
    minimize heat damage to nutrient and flavor components.
Theoretical thermal destruction curves of pectin methyl esterase,
ascospores and vegetative cells of Saccharomyces cerevisae in
orange juice (The Orange Book, Tetra Pak)
challenges
packaging


         •   trend towards less glass and increased use of
             polypropylene and PET (polyEthyleneTerephthalate)
         •   scalping
             (loss of flavor into the packaging material)
         •   permeation
             (movement of compounds through packaging materials)
         •   migration
             (movement of components of the packaging material into
             food product)




  Source: Risch, S. 2000. Flavor and packaging interactions. In: Flavor Chemistry, ed. By
  Risch, S.J and Ho, C.T. American Chemical Society. Pages 94-100.
Barrier properties


                              Off-flavor formation


             Oxygen                                  oxidation




                                                     Flavor


                Flavor fading (scalping, permeation)


      Permeation rate = Diffusion x Solubility
      P=DxS
Vitamin C stability in different package types
(The Orange Book, Tetra Pak)




        AA + ½ O2 = DHA + H20
        AA = ascorbic acid (vitamin C), DHA = dehydroascorbic acid
Properties of different polymers: P = D x S

Polar polymers: PET, ethylene vinyl alcohol (EVOH) and polyamide (PA)
  show very slow diffusion coefficients with polar and non-polar aroma
  compounds.


Non-polar polymers: low density polyethylene (LDPE), high density
  polyethylene (HDPE) and polypropylene (PP)


Limonene (non-polar aroma compound) has a high solubility in all the non-
  polar polymers and diffusion and consequent permeation rates differ by
  orders of magnitude in the different polymers – in decreasing order
                    LDPE > HDPE > PP


Ethyl butyrate (polar aroma compound) has low solubility in non-polar
  polymers. Losses of polar molecules are negligible with this type of barrier.
Terpenes: the largest single chemical class within citrus volatiles




*Three month study of orange juice in Tetra-Pak laminated containers showed:
(a)   Significant loss of limonene due to absorption/scalping by polymer barrier
(b)   a-terpineol (formed from degradation of limonene) increased more rapidly
      at higher storage temperatures
      *Duerr et al., Alimenta 1981, 20, 91-93
 Volatile contribution to orange juice aroma


Contribution to typical aromas     Contribution to off-notes
Important           Desirable      Precursors   Detrimental


ethyl butyrate      linalool       linalool     a-terpineol
neral               limonene       limonene     carvone
geranial            a-pinene       valencene    t-carveol
                    valencene                   4-vinyl guaiacol
                    acetaldehyde                2,5-demethyl-4-
                                                hydroxy-3-(2H) furanone
                    octanal
                    nonanal
                    a-sinensal
                    b-sinensal
flavoring   beverages

            •background

            •opportunities

            •challenges

               •citrus flavor stability
               •orange juice processing
               •clouds
               •milk & coffee drinks
challenges
clouds


         • provides turbidity to a beverage; visual enhancement that gives
           finished beverage more value

         • many different types of cloud systems
         • weighting agents in clouds are regulated
         • sucrose acetate isobutyrate (SAIB)

         • brominated vegetable oil (BVO)
         • ester gum

         • blended systems
challenges
clouds




         Neutral cloud

           Goal: cloud with minimal taste impact

             Most made from orange terpenes

             Vegetable oil as an alternative

                • typically less stability

                • cleaner taste
challenges
cloud ringing



   emulsion in beverage product breaks down giving rise to creaming

   perform tests to predict stability
     • make assumptions for predictions
     • microscope, particle size analyzer, shelf-life studies etc.
challenges
cloud ringing



  Stokes Law:
                                   V = 2gr2 (po-p)
                                          9no
  v = velocity
  r = droplet radius
  g = gravity
  po - p = difference in density
  no = viscosity


          v = negative             creaming
          v=0                      stable cloud
          v = positive             sedimentation
challenges
cloud ringing

                                    ringing

   stable




                phase separation,
                shrinkage of cloud layer
flavoring   beverages

            •background

            •opportunities

            •challenges

               •citrus flavor stability
               •orange juice processing
               •clouds
               •milk & coffee drinks
milk-coffee RTD          challenges
matrix complexity




                    milk-coffee drinks contain coffee, milk,
                    sweeteners, flavors, salts, hydrocolloids, proteins,
                    emulsifiers amongst other components


                       complex mixture of ingredients


                       physico-chemical and flavor stability issues
                        (processing and storage)
Milk coffee RTD matrix

Milk coffee RTD matrix

                                      Coffee



  Black        Fresh whole milk              Specialty proteins     Alternative systems
  Coffee       Fresh skimmed milk
               Skim/whole milk powders
                                                Caseinate
                                                                           Clouds
                                               Whey proteins

                                                  Others                   Others


                                                       Dairy/non-dairy fat with milk flavour


                 Effect of heating, antioxidants, pH, O 2 content, stabilizing salts,
 Processing
                 homogenization etc.


    R&D                  Application, Sensory & Flavour expertise        Emulsifiers, Proteins
                                                                           Hydrocolloids

              Beverages with improved stability & fresher coffee flavour
milk-coffee RTD                 opportunities
consumption


coffee consumption is growing
     2.5 billion liters of canned coffee are
      consumed annually in Japan alone!
      served hot during winter & cold in summer
     beverage manufacturers are adopting coffee
      house trends into RTD‟s
milk-coffee RTD              challenges
flavor complexity



        • coffee contains over 830 volatile components!
        • some of the key flavor components responsible for fresh
           roast coffee character are:
           • 2-furfurylthiol

        • coffee aroma and taste is dependent on the type of coffee used
          • species: Arabica or Robusta
          • origin
          • degree of roasting
milk-coffee RTD               challenges
flavor complexity



        at temperatures > 60°C, acidity increases, sourness increases and
           volatiles are lost resulting in an unpleasant drinking experience
        milk is added to coffee for:
           appearance
           taste
           mouthfeel
LC Fractionation of Arabica Coffee (filtered brew)
milk-coffee RTD              challenges
flavor complexity


  • coffee flavors are needed to compensate for the damage to the coffee
     volatiles during the extraction and beverage processing stages
     • fruity (eg. acetaldehyde)
     • phenolic (eg. guaiacol)
     • earthy (eg. 2-ethyl-3,5-dimethylpyrazine)
     • roast (eg. 2-furfurylthiol)
     • sweet (eg. methylpropanal)

  • opportunities for flavored coffees include;
    • vanilla                            • amaretto and almond
    • Irish Cream
    • chocolate and caramel
                                         • coconut
    • macadamia Nut and Hazelnut • fruit flavors                      eg.
                                       orange & raspberry
The composition of milk




            CONSTITUENT    RANGE %       MEAN VALUE %

            Water          85.5 – 89.5       87.0
            Total solids   10.5 – 14.5       13.0
            Fat             2.5 – 6.0        4.0
            Protein         2.9 – 5.0        3.4
            Lactose         3.6 – 5.5        4.8
            Minerals        0.6 – 0.9        0.8
Main fatty acids of milk fat



                           % OF TOTAL FATTY    MELTING
             CONSTITUENT
                            ACID CONTENT       POINT °C

             Butyric            3.0 – 4.5        –7.9
                                              85.5 – 89.5
             Caproic            1.3 – 2.2        –1.5
             Caprylic           0.8 – 2.5        16.5
             Capric             1.8 – 3.8        31.4
             Lauric             2.0 – 5.0        43.6
             Myristic          7.0 – 11.0        53.8
             Palmitic          25.0 – 29.0       62.6
             Stearic           7.0 – 13.0        69.3
             Oleic             30.0 – 40.0       14.0
             Linoleic           2.9 – 3.1        –5.0
Distribution of the major constituents of the casein micelle
between the serum and micellar phases of bovine milk at pH
6.7 at 20°C




                        MICELLAR PHASE SERUM PHASE
           COMPONENT
                              (g/l)        (g/l)

           as1-Casein        10.9           0.7
                                        85.5 – 89.5
           as2-Casein        3.0            0.1
           b-Casein          9.0            1.3
           k-Casein          2.9            0.5
           Calcium           0.8            0.4
           Phosphate         0.9            1.1
           Citrate           0.1            1.8
Some physico-chemical characteristics of casein micelles

      CHARACTERISTIC                   AVERAGE VALUE

      Diameter                         130-160 nm
      Surface area                     8.0 x 10-6 cm2
      Volume                           2.1 x 10-5 cm3
      Mass                             2.2 x 10-15 g
      Density (hydrated)               1.0632 g/cm3
      Water content (hydrated)         63%
      Hydration                        3.7 g H2O/g protein
      Voluminosity                     4.4 cm3/g
      Zeta potential (at 25°C)         –18.7  0.3 mV
      Particle weight (hydrated)       1.3 x 109 Da
      Particle weight (dehydrated)     5 x 108 Da
      No. of monomers (av MW 25,000)   5 x 103
Schematic representation of a sub-micelle (A) and a
casein micelle (B) composed of sub-micelles (from
Schmidt, 1982)
Possible reactions of side-chain residues
of proteins at high temperatures – 1

   1. -CH2-CONH2 + H2O            -CH2COOH + NH3
      Asparagine                  Aspartic acid

   2.   -(CH2)2-CONH2 + H2O       -(CH2)2-COOH + NH
        Glutamine                 Glutamic acid

   3. -CH2-O-PO32- + H2O          -CH2-OH + HPO42-
      Phosphoserine               Serine

   4.   -CH2-O-PO32-              =CH2 + HPO42-
        Phosphoserine             Dehydroalanine

   5.   -CH2-SH + OH-             -CH2-S- + H2O
        Cysteine
   6.   R1-CH2-S-S-CH2-R2         R1/R2-CH2-S-
        R3-CH2-S-                 R3-CH2-S-S-CH2-R1/R2
Possible reactions of side-chain residues
of proteins at high temperatures – 2

   7. -CH-S- + -S-                      -CH2-S-S-CH2
      CH2-                              Cystine
      Cysteine
   8. -CH -S-
         2
                                        =CH2 + HS-
      Cysteine                          Dehydroalanine
   9. =CH2 + HS-CH2-                    -CH2-S-CH2
                                        Lanthionine

   10. -(CH ) -NH + + H C + OH-           -(CH2)4- +NH-CH2- + H2O
            24   3     2                  Lysinoalanine
       Lysine
   11. -(CH ) -NH + + -O C-CH             -(CH2)4-NH-CO-CH2 +
            24   3      2      2          H2O + e-N-(B-aspartyl)lysine
       Lysine          Aspartic acid
   12. -(CH ) -NH + + -O C-(CH ) -        -(CH2)4-NH-CO-(CH2)2- +
            2 4  3      2      22
       Lysine           Glutamic acid     H2O + e-N-(g-glutamtyl)lysine
Browning (Maillard) reactions in milk




       in milk the main Maillard reactants are lactose and lysine

       the rate of Maillard reaction in milk is dependent on pH, time,
        temperature and water activity

       some of the compounds identified from „dry‟ extracts of milk
        systsems incubated at pH 6 or 7 and water activity 0.75 to
        0.80 included: 5-hydroxymethyl-furfural, furfuryl alcohol,
        furfural, maltol, acetol, 2-oxo-proponal, acetaldehyde, and
        formic, acetic, propionic, butyric and lactic acids
Heat stability versus pH curves
for normal skim milk heated at 140°C



          HEAT COAGULATION TIME (HCT) (min.)
     50


     40

                                  maximum
     30
                       milk A                              milk B
     20
                                             minimum
     10


      0
      6.2        6.4            6.6        6.8         7      7.2

                                      pH
Changes which can occur to milk constituents on heating – 1



            calcium and phosphate are converted from soluble to
             colloidal state

            formic acid and lactulose are formed from lactose at
             temperatures > 100°C

            hydrolysis of the phosphoserine residues at high
             temperatures

            the titratable acidity of the milk increases and pH
             decreases

            solubility of the whey proteins decreases significantly at
             temperatures > 75°C
Changes which can occur to milk constituents on heating – 2




           enzymes are inactivated by heating at > 50°C, but varies
            with enzyme

           there is a decrease in redox potential probably due to the
            formation of free sulphydryl groups and hydrogen sulphide
            formation at temperatures > 60°C

           Maillard reactions increase as temperature of heating
            increases

           casein micelles may start to aggregate above 110°C

           lactones and methyl ketones are formed from the fat
Alkaline urea-PAGE of solutions of sodium caseinate
heated at different pH values and temperatures.




    as1-casein
    as2-caseins
                                               Alkaline urea-PAGE of
                                               unheated sodium
       b-casein                                caseinate (1); sodium
                                               caseinate, pH 7, heated
                                               at 110°C (2), 120°C (4),
       k-casein                                of 130°C (6) for 5 min.
                                               and sodium caseinate,
       g-casein                                pH 10.0, heated at
                                               110°C (3), 120°C (5)
                                               or 130°C (7) for 5 min.
                                               Lynch, Andrew, Ph.D thesis,
                                                NUI, Cork, Ireland, 1995.
                   1   2   3   4   5   6   7
milk-coffee RTD               challenges
preparation of milk-coffee beverages


Coffee-milk mixtures usually have near neutral pH values and careful
processing is required to ensure a stable product with good organoleptic
properties


     •   controlled temperature & duration of heating during coffee extraction
     •   homogenization is required if milk fat or other fat is used
     •   sufficient amount of surface active material must be present
     •   check coffee-milk/ingredient and flavor compatibility
     •   pH of the mixture needs careful control
     •   sterilization/UHT processing is required for long shelf-life products
milk-coffee RTD           challenges
why homogenize?




            under homogenization   optimum homogenization
milk-coffee RTD               challenges
emulsion stability



                                                       OIL




            Creaming                Aggregation   Coalescence
                                     creaming      separation


                       Reversible                  Irreversible
       STABLE                                             UNSTABLE
milk-coffee RTD               challenges
droplet stabilitly
                                close approach of
                                droplets



                                steric stabilization


               coalescence               interfacial film
                                           rupture

                                      interfacial rheology




                                                   no interfacial film
                                                   rupture


                       flocculation
Emulsifiers




             Surface active molecules


             Contain water-loving hydrophilic part and oil-loving
              lipophilic part


             Reduce surface tension


             Orientate at oil / water or air / water interface


             Interact with other ingredients (e.g. protein, starch)
Emulsifiers : Chemical Characteristics



           Iodine value               unsaturated fatty acids
               gram iodine absorbed per 100 g emulsifier

           Peroxidase value                   oxidation level
               meq. oxygen bound as peroxide per kg emulsifier

           Acid value                  free fatty acids
               mg KOH needed to neutralise 1 g emulsifier

           Saponification value               free + bound fatty
            acids
               mg KOH needed to saponify 1 g emulsifier
Composition of emulsifiers
Hydrophilic / Lipophilic Balance of Emulsifiers
Monoglyceride : Saturated




               -o-

        E
                     CO

               -          Fatty
               OH         acid
               -
               OH



 GMP
 (glyceromonopalmitate)
Sodium stearoyl-2-Lactylate




           CH3
           |
      CH3 CHO CO
      |     |
      CHO--CO         Fatty
                      acid
      |  -    +
      COO (Na )
milk-coffee RTD              challenges
effect of homogenization pressure on particle size distribution
flavoring   beverages

            •background

            •opportunities

            •challenges

               •citrus flavor stability
               •orange juice processing
               •clouds
               •milk & coffee drinks
Flavoring Beverages:
Opportunities and Challenges
A.G. Lynch

				
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