Soft drinks flavour standards kit used to train professional tasters to recognize and scale the intensity of eight off-flavours.
Use them to deliver up to 20 hours of taster training for ten people. Comes complete with presentation case and one set of soft drinks flavour cards.
AROXA™ certified soft drinks flavour standards are: food grade | free from sensory impurities | extensively tested | safe to smell and taste. Unsure whether this kit is right for you? Don’t forget about our 100% satisfaction guarantee.
The importance and origins of each flavour are:
Flavour: ACETALDEHYDE Chemical name: ACETALDEHYDE
“Acetaldehyde, like green apple, fermenting fruit or emulsion paint”
IMPORTANCE: Low levels of acetaldehyde contribute to apple character, cleanness and complexity of soft drinks. Acetaldehyde is an off-flavour at high concentrations when the note resembles emulsion paint.
ORIGINS: Acetaldehyde is present in fruit extracts and juices. It occurs in higher levels in soft drinks and juices as a result of product spoilage through alcoholic fermentation of sugar by contaminant yeasts and bacteria. At low levels it can arise in soft drinks through degradation of plastic bottles.
Flavour: ACETIC Chemical name: ACETIC ACID
“Acetic, like vinegar”
IMPORTANCE: Acetic acid imparts a vinegar-like odour to soft drinks and a common indicator of microbiological spoilage. The acidity is apparent both in terms of smell and taste.
ORIGINS: Acetic acid is produced by contaminating bacteria and yeasts. The flavour is more common in the case of products which are exposed to oxygen, such as those which are served via post-mix dispense systems.
Flavour: DIACETYL Chemical name: 2,3-BUTANEDIONE
“Diacetyl, like butter, butter popcorn, or warm milk”
IMPORTANCE: Diacetyl imparts a sweet, butter-like note. Its presence can be indicative of microbiological spoilage of soft drinks by lactic acid bacteria or by alcoholic yeasts.
ORIGINS: Diacetyl (2,3-butanedione) is produced by contaminant lactic acid bacteria (Lactobacillus, Pediococcus, Leuconostoc). Some yeasts produce a precursor of this compound which can give rise to 2,3-butanedione formation during product storage.
Flavour: BUTYRIC Chemical name: BUTYRIC ACID
“Butyric, like cream liqueur, toffee or baby vomit, rancid”
IMPORTANCE: Butyric acid imparts a rancid note to soft drinks, reminiscent of baby vomit, which is especially prominent in products of low pH value. While regarded as desirable in some types of confectionery, it is generally rejected by consumers of soft drinks.
ORIGINS: Butyric acid is produced in sugar syrups by bacteria, including Bacillus spp. and Clostridium spp. It is also occasionally caused by penetration of adhesive label components into soft drinks which have been packaged in plastic bottles.
Flavour: SMOKY Chemical name: GUAIACOL
“Smoky, like smoked fish or cheese”
IMPORTANCE: Guaiacol imparts an undesirable smoky / disinfectant-like note to affected soft drinks and fruit juices. The flavour tends toward a more medicinal note when bromophenols, formed by the same contaminant bacteria, are present.
ORIGINS: The presence of guaiacol in soft drinks can be caused by growth of Alicyclobacillus bacteria in packaged product or in ingredients. This microorganism is acidophilic and survives pasteurization. It converts vanillin present in the product, and derived from ingredients and / or flavourings, to less desirable guaiacol.
Flavour: H2S Chemical name: HYDROGEN SULPHIDE
“H2S, like boiled eggs or rotten eggs”
IMPORTANCE: Hydrogen sulphide imparts an unpleasant sulphury note to contaminated soft drinks. H2S is easily oxidized to less odour-active species, so its presence is indicative of the failure of water treatment processes or contamination arising during production of soft drinks.
ORIGINS: H2S is a contaminant of carbonated soft drinks which can be introduced through use of insufficiently-purified carbon dioxide. It can also arise through microbiological spoilage by bacteria, and through chemical reactions involving metal surfaces in canned products.
Flavour: KEROSINE Chemical name: 1,3-PENTADIENE
“Kerosine, like petroleum or geranium”
IMPORTANCE: 1,3-Pentadiene imparts a potent ‘chemical’ taint to affected products. It is typically described as kerosene-like, with additional descriptors of plastic, paint, and geranium depending on the nature of the affected product. Styrene may also be formed together with 2,3-pentadiene by some organisms. during spoilage of soft drinks and fruit juices, or the ingredients from which they are made, by moulds.
ORIGINS: 1,3-Pentadiene is produced by contaminant microorganisms. Moulds such as Penicillium and Trichoderma, and yeasts such as Zygosaccharmoyces and Debaromyces convert odourless sorbic acid used as a preservatives in some soft drinks and fruit juices into the highly odour active molecule 1,3-pentadiene.
Flavour: PLASTICS Chemical name: STYRENE
“Plastics, like polystyrene or model aeroplane glue”
IMPORTANCE: Styrene is often described by consumers as ‘chemical’, ‘plasticy’ (like polystyrene) or ‘contaminated’. When formed by yeasts or moulds, additional compounds such as 4-vinyl guaiacol and 1,3-pentadiene may be present which can modify the flavour making the drink more ‘medicinal’, ‘smoky’ in the case of guaiaco, or like kerosine in the case of pentadiene.
ORIGINS: Styrene can contaminate plastic bottles and, in turn, impart a taint to the soft drinks or juices packaged into these bottles. It can also arise from the action of contaminant yeasts and moulds. Use of defective carbon dioxide is occasionally to blame for styrene contamination incidents.