New science clarifies flavour balance for orange juice matrix
made strides towards designing more precise flavour profiles for
better quality citrus juices that will ultimately cut costs for
beverage manufacturers and provide consumers with an accurate taste
of freshly squeezed orange juice, writes Lindsey Partos.
Developing higher-quality flavour packs that more closely mimic fresh juice flavour will provide juice makers with a competitive advantage in the global market.
When orange juice is produced, aroma compounds evaporate away during the condensing process used to make frozen concentrated orange juice.
The 40 detectable aroma compounds - blended into mixtures - are then sold to juice companies as 'flavour packs' from ingredients companies such as Danisco or Kerry, and are added back into the juice along with water before the juice is marketed.
Researchers at the Agricultural Research Service, the US government science agency, have so far identified the thresholds - how much of the component needs to be present for the consumer to taste it - of 14 different flavour profiles.
"Understanding the thresholds will ultimately improve the quality of the end product for the industry," Elizabeth Baldwin, the study's lead researcher, explained to FoodNavigator.com.
The ARS team, based in Florida, the heart of the US citrus growing zone, are half way through their research to map the 40-odd aroma compounds in orange juice.
Baldwin explained the motivation behind the study: "We set out to update a database for the industry on the thresholds of flavour compounds, to help juice makers and flavour houses produce an improved fresh orange juice profile."
In order to achieve this, they unravelled the interactions between all the compounds in juice, a complex mixture. In addition to flavour compounds, juice contains sugars, acids, pulp, pectin, salts, and phenolic compounds, which can all influence perception of flavour.
The researchers identified odour and taste thresholds of compounds considered to be important contributors to the orange juice flavour.
"One at a time we added a known amount of the flavour compound back into deodorised juice, at five different levels that spanned the estimated threshold level." Fifty participants then gave their opinion by smelling and tasting 15 different samples of chilled orange juice.
"This combined orthonasal (smelling through the front of the nose) and retronasal (the aroma going to the nose through the back of the throat) olfactory testing is really important to those in the citrus industry who are trying to formulate flavours," said Baldwin.
The database is freely available to the industry and will eventually contain the 40 flavour compounds that make up the complex matrix of orange juice.
Beverage industry analysts Canadean report that North America is by far the biggest market for juice and nectars, accounting for over 35 per cent. Canada's consumption has risen by more than 45 per cent since 1997, giving Canadians the highest per capita consumption in the world.
And while the US is the biggest single market in pure volume terms, it is Canada and Germany which lead the rest of the pack when it comes to per capita consumption. Orange is particularly popular there, with the flavour's share some 18 percentage points higher then the global average.
Total consumption in the US declined slightly in 2002 and is expected to have grown only modestly during 2003. Western Europe is the second largest regional market, and Canadean said that demand there tends to be higher in the northern countries - in the south of the continent, fresh fruit is more popular.
