Electronic-nose technologies have gained significant attention in sensor technology over the past two decades due to their diverse applications in various fields. Recent advancements in sensor design, materials, software, and microcircuitry have enabled the development of new e-nose sensor types and arrays, expanding their applications. These devices, known as electronic noses, mimic the mammalian olfactory system, allowing the identification and classification of aroma mixtures without identifying individual chemical components. They are used in various commercial industries, including agriculture, biomedical, cosmetics, environmental, food, manufacturing, military, pharmaceutical, and scientific research. Advances in e-nose technology have improved product attributes, uniformity, and consistency by enhancing quality control capabilities during industrial processes. The olfactory sense has long played a crucial role in human development and biosocial interactions. Aromas are complex mixtures of volatile compounds that can be detected by animals through olfaction. Aromas are characterized by four dimensions: threshold, intensity, quality, and hedonic assessment. Aromatic compounds have low molecular masses and are often volatile, contributing to their unique qualities. Aromas are categorized into various types, such as earthy, floral, fruity, spicy, fishy, sewage, medicinal, and chemical. These categories help in describing and quantifying aromas. Biological olfaction involves the detection of odors through the interaction of olfactory receptors with volatile compounds. The sensitivity to aromas varies among individuals and is influenced by factors such as the nature of the aroma, sex, age, and health. Aromas and tastes can be affected by certain illnesses, leading to conditions like anosmia, hyposmia, and parosmia. The detection threshold for aromas varies depending on the compound and the individual. The concept of the electronic nose was developed in the 1980s, with the first studies involving aroma measurements in the 1920s. The electronic nose consists of a sensor array, an information-processing unit, software, and reference-library databases. The sensor array is composed of incrementally different sensors that respond to a wide range of chemical classes. The output from individual sensors is integrated to produce a distinct digital response pattern, which is used to identify and classify aroma mixtures. Electronic nose sensor types include metal-oxide, semiconductive polymers, conductive electroactive polymers, optical, surface acoustic wave, and electrochemical gas sensors. Each sensor type has its own advantages and limitations, with conducting polymers and electrochemical sensors being particularly versatile due to their operation at ambient temperatures, low power consumption, and good sensitivity to a wide range of gases. The choice of sensor type depends on the specific application and the requirements of the analysis. Electronic nose instrumentation includes an aroma delivery system, a chamber for sensors, an electronic transistor, a digital converter, and a computer microprocessor. The aroma delivery system is crucial for transferring volatile compounds to the sensor array. The sensor array is the most importantElectronic-nose technologies have gained significant attention in sensor technology over the past two decades due to their diverse applications in various fields. Recent advancements in sensor design, materials, software, and microcircuitry have enabled the development of new e-nose sensor types and arrays, expanding their applications. These devices, known as electronic noses, mimic the mammalian olfactory system, allowing the identification and classification of aroma mixtures without identifying individual chemical components. They are used in various commercial industries, including agriculture, biomedical, cosmetics, environmental, food, manufacturing, military, pharmaceutical, and scientific research. Advances in e-nose technology have improved product attributes, uniformity, and consistency by enhancing quality control capabilities during industrial processes. The olfactory sense has long played a crucial role in human development and biosocial interactions. Aromas are complex mixtures of volatile compounds that can be detected by animals through olfaction. Aromas are characterized by four dimensions: threshold, intensity, quality, and hedonic assessment. Aromatic compounds have low molecular masses and are often volatile, contributing to their unique qualities. Aromas are categorized into various types, such as earthy, floral, fruity, spicy, fishy, sewage, medicinal, and chemical. These categories help in describing and quantifying aromas. Biological olfaction involves the detection of odors through the interaction of olfactory receptors with volatile compounds. The sensitivity to aromas varies among individuals and is influenced by factors such as the nature of the aroma, sex, age, and health. Aromas and tastes can be affected by certain illnesses, leading to conditions like anosmia, hyposmia, and parosmia. The detection threshold for aromas varies depending on the compound and the individual. The concept of the electronic nose was developed in the 1980s, with the first studies involving aroma measurements in the 1920s. The electronic nose consists of a sensor array, an information-processing unit, software, and reference-library databases. The sensor array is composed of incrementally different sensors that respond to a wide range of chemical classes. The output from individual sensors is integrated to produce a distinct digital response pattern, which is used to identify and classify aroma mixtures. Electronic nose sensor types include metal-oxide, semiconductive polymers, conductive electroactive polymers, optical, surface acoustic wave, and electrochemical gas sensors. Each sensor type has its own advantages and limitations, with conducting polymers and electrochemical sensors being particularly versatile due to their operation at ambient temperatures, low power consumption, and good sensitivity to a wide range of gases. The choice of sensor type depends on the specific application and the requirements of the analysis. Electronic nose instrumentation includes an aroma delivery system, a chamber for sensors, an electronic transistor, a digital converter, and a computer microprocessor. The aroma delivery system is crucial for transferring volatile compounds to the sensor array. The sensor array is the most important