Acidulants

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Acidulants

• Acids and their salts serve a variety of
  functions in foods that include the following
• 1. Flavoring to provide a desired taste and serve
  to intensify, enhance, blend of modify the
  overall flavor of the product.

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Acidulants

• 2. Reduction of the pH to prevent or retard the
  growth of microorganisms and the germination of
  spores and to increase the lethality of the
  process.
• 3. Maintaining or establishment of pH by serving
  as buffering agents. Usually a combination of
  free acids and salts are used.

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Acidulants

• 4.Chelation of metal ions to assist in minimizing
  lipid oxidation (Cu, Fe), reducing color changes
  and controlling texture in some fruits and
  vegetables.
• 5.Alteration of the structure of foods including
  gels made from gums (pectin, carrageenan), and
  proteins.

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Acidulants

• 6.Interaction with proteins and emulsifiers to
  modify the structure of foods such as doughs,
  alter the heat stability of proteins, and to
  serve as an emulsifier in processed cheese.
• 7. Modification of sugar crystallization in hard
  candy manufacturing.
• http//www.foodproductdesign.com/archive/1993/0593
  DE.html

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Major Differences In Acidulants

• 1. Flavor
• 2. Acidity
• 3. Metal Chelating Activity
• 4. Anti-microbial Activity
• 5. Solubility
• 6. Hydroscopicity
• 7. Cost

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pKas of Food Acids

• ACID pKa
• Acetic 4.75
• Phosphoric 2.1, 7.2, 12.3
• Citric 3.08, 4.74, 5.4
• Lactic 3.86
• Hydrochloric
• Sulfuric --, 1.92
• Carbonic 6.4,10.3
• Malic 3.4, 5.1

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pKas of Food Acids

• ACID pKa
• Succinic 4.2, 5.6
• Tartaric 3.2, 4.8
• Fumaric 3.03, 4.44
• Adipic 4.43, 4.41
• Gluconic 3.60
• Pyrophosphoric 0.9, 1.5, 5.8, 8.2

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Acids and Taste

• Acetic vinegar like
• Citric sharp, clean bite
• Fumaric acid taste lingers
• Malic builds slowly and lingers
• Most acids modify the sweetness of sugar

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Taste of Acids
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Solubility

• Varies with acid
• Degree and rate varies with temperature
• Fumaric poorly soluble in cold water
• Encapsulation sometime used to delay solubility

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Solubility of more soluble acids
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Solubility of Less Soluble Acids
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Moisture Absorption
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Citric Acid

• Accounts for 60 of all acids used.
• Helps preserve color, aroma and and vitamine
  content of canned foods
• pH control, stong chelator, antioxidant,
  synergist
• Excellent solubility
• Provided buffering capacity pH 2.5-6.5
• Cultured dairy products-substrate for flavor
  production
• Processed cheese-alter protein and emulsify
• Evaporated milk-stabilize protein to heat
• Honey-retard crystallization

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Phosphoric Acid

• Phosphoric acid-Accounts for 25
• Major use - cola
• The acid that, through no fault of its own, has
  many other functions. ie Chelator, ionic bridges

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Lactic Acid

• Flavor
• Moderate chelator
• pH adjustment
• Anti-microbial activity
• Coagulating agent

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Malic Acid

• Flavor
• Moderate chelator
• pH adjustment

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Tartaric Acid

• Moderate chelator
• Buffering capacity pH 3.5-4.5
• Baking powder-leavening acid
• Fruit butters, jams, sherbets, jellies-flavor, pH
• Hard candies-flavor, crystallization control
• Artificial sweetener - bitter masking

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Glucono Delta Lactone

• Slowly soluble
• Soluble in hot water
• Hydrolyzes to form gluconic acid
• Direct set cottage cheese
• and Mozzarella
• Tofu (aseptic, instant)
• Leavening

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Adipic Acid

• Gelatin powder-pH control to alter texture
• Baking powder-leavening acid
• Fruit products-tartness
• Processed cheese-sequesterant for better melting
• Meringue-whipping aid

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Succinic acid

• Bread dough-modifies plasticity
• Gelatin powder-Controlled pH adjustment to
  regulate texture
• Soluble in hot water

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Acetic Acid (Vinegar)

• Products
• Mayonnaise, sauces, pickles, dressings, natural
  breads
• Functions
• pH control, flavor, shelf-life
• Always a flavor impact

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Ascorbic Acid

• Not generally used as an acidulant
• Strong reducing agent
• Acts as an antioxidant (and is oxidized)
• Stabilized by citric acid

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Sodium Acid Sulfate (SAS)

• Solid form of sulfuric acid
• NaHSO4

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Acids Summary

• pH adjustment may not require listing on
  ingredient label (processing aid)
• Mineral acids may allow pH adjustment without as
  much flavor as organics
• If something other than phosphoric or citric is
  used there must be a reason for it
• Slow release of acid has many uses