Acidulant

pH control agent

•With the aid of buffering capacity
•Citric acid-widest buffer range (pH 2.5 to 6.5)
•Tartaric acid only between pH 3.0 and 4.5

Preservatives

Chelating agents / antioxidant synergists

•Form ring structure with metal ions---chelation
•Eg. Citric acid- strongest chelating agent
•Other example: lactic, malic, tartaric acid

Control of gelation and coagulation

•Gelling HM pectin pH adjusted to 2.5-3.5
•Cheese making- lower pH for curd formation

Flavor adjuncts

Citric acid

•High solubility in water
•Appealing effects on flavor
•Deliver ‘burst’ of tartness
•Strong metal chelation properties

Phosphoric acid and phosphates

•The ONLY inorganic acid
•At concentration <5%, phosphates used in emulsification, buffering, metal sequestration, control of protein coagulation, dispersion of proteins
•Used in production of natural cheese for pH adjustment
•Phosphate chelate calcium required for bacteriophages
•As chemical leavening agent
•Increase retention of natural juices

Acetic acid

•Major component of vinegar
•pH reduction
•Control of microbial growth
•Enhancement of flavour

Fumaric acid

•From fermentation of glucose or molasses by certain Rhizous spp.
•Very low hygroscopicity

Malic acid

•Does NOT exhibit ‘burst’ effect as citric acid
•High water solubility
•Impart smooth and tart taste that lingers in the mouth
•Mask the after-tastes of low- or non-caloric sweeteners

Lactic acid

•Inhibit growth
•Retard spoilage
•Retard further fermentation
•Natural; mild and lingering
•Good for creamy flavours with fruit notes
•Enhances flavours