Orange juice is a preferable morning nectar to be consumed for breakfast by the people worldwide. The presence of Diacetyl and Limonene in it would surely be extremely undesirable as these two harmful components not only destroy the taste but also could be hazardous. The occurrence of these compounds can take place through microbiological contamination due to poor processing or handling procedures. Limonene, a colorless liquid hydrocarbon is classified as a cyclic terpene and is more common d-isomer that possesses a strong smell of oranges. It has a detrimental impact on cellular health if consumed for long. It also has been associated with neurodegenerative diseases and general cell aging.  Whereas, diacetyl, an organic compound is a yellow/green liquid that has a buttery flavor. Its exposures could lead to hazardous flavorings in orange as well as other fruit juices due to its toxic properties.

These undesirable materials mainly do not set back flavor, unless at concentration level is extremely high. Therefore, quantifying the accurate amount of the presence of Diacetyl and Limonene in orange juice is imperative before it reaches the consumers. California-based EST Inc. has invented a unique electronic nose called zNose® that quantifies the concentration of hydrocarbons and detects the presence of undesired components in orange juice within a minute. The zNose® is specially designed to support quality control testing of aroma and flavor virtually in any food or beverage.

This unique technology is very fast and possesses the ability to analyze the chemistry of any vapor over the range C4-C20 using a 1-meter db-624 capillary column. It can speciate and quantify the discrete chemicals present in any odor, smell, fragrance, vapor, or odor in a minute with part per billion sensitivity, unlike an array of physical sensors.  The zNose® also produces high-resolution visual olfactory images, called VaporPrints™ and hundreds of virtual chemical sensors simultaneously.

Testing Limonene & Diacetyl in Orange Juice:

Testing Standards-

• For quantifying the presence of Limonene & Diacetyl in Orange Juice fast, keep the temperature programming as high as 18°C/second.
• Full hydrocarbon spectrum viewing C4-C20 is accomplished by ramping the db-624 column temperature from 40°C to 140 °C in 10 seconds.
• Conversely, the maximum resolution is achieved using isothermal column conditions (40°C to 150°C).

Testing Limonene in Orange Juice-

• Clear zNose® using Air Blank and 10ps-0
• Create orange juice standard
• Pre-concentrate headspace vapors from orange juice standard
• Analyze orange juice with zNose® using 10ps-0 method
• Clear zNose® using Air Blank and 10ps-0 method

Testing for Diacetyl in Orange Juice-

• zNose® initialized by clearing the air blanks using 10ps-0 method.
• Create diacetyl/orange juice standards.
• Tenax absorber air blanks (170°C) using 10ps-0 method.
• Cool, Tenax absorber to room temperature.
• Pre-concentrate headspace vapors from diacetyl/orange juice standard.
• Dry the tenax absorber.and raise it to 170°C.
• Analyze tenax vapors with zNose® using 0ps-0 method.
• Tenax absorber air blanks (170°C) using 10ps-0 method.

Hence, zNose® possesses the ability to detect and quantify the presence of harmful components such as Limonene & Diacetyl in orange juice easily within a minute with speed, precision, and accuracy. It also capable of carrying over 300 measurements per day which proffers a cost effective quality control tool with a payback period of 30 days in most of the situations. Therefore, zNose® is a utilitarian device which is a one stop solution to keep the quality check in order to give the consumers a healthy and safe taste of nature.