Page 65 - FoodFocusThailand No.198 September 2022

STRONG QC & QA

The IST included 3 technologies: Applications of Intelligent Sensory Techniques for
1. Electronics Nose (E-nose) The E-nose is composed of an Alcoholic Beverages
array of electronic chemical sensors with appropriate pattern-recognition The use of IST technology to study the flavor composition of alcoholic
systems, which can identify individual volatile or complex chemical beverages, especially the changes during production process and
mixtures that constitute aromas, odors, fragrances, formulations, spills, storage, is always a research hotspot in the alcohol industry. Each
and leaks. The working principle of the E-nose is to simulate the human alcoholic beverage has its own unique flavor characteristics. IST
olfactory organ through the gas sensor array, then perceive and analyze technology can analyze aroma profiles by registering signals produced
the odors, and transmit the collected signals information to the analysis by the mixture of gases and then comparing the pattern of responses
software for classification or identification. E-noses have been produced by different samples.
extensively developed in recent years and have been available IST has been applied in quality assessments of alcoholic beverages
commercially and used in diverse industries. in terms of variety and geographical origins, monitoring production
processes, detection of frauds and adulterations, discrimination of years
of aging, distinguishing brands and types, aroma analysis, and detection
of spoilage and off-flavors.
Fraud and Adulteration Detection
Alcohol adulteration is commonly occurring by a mixture of methanol
and ethanol with other alcohols of the same color, which has damaged
the reputation of the alcohol market and the benefit of consumers. To
avoid adulteration and market cheating, a rapid, reliable, and
accurate detection technology for authentication of alcoholic beverages
is essentially required to prevent illegal adulteration. In recent years,
electroanalytical techniques have been widely used in frauds and
adulterations of alcoholic beverages. The electroanalytical system
equipped with various sensors and coupled with multiple pattern
recognition methods, such as E-nose and E-tongues, has been widely
applied in alcohol beverage authentication. To summarize, this system
2. Electronics tongue (E-tongue) The E-tongue is a multi-sensor will use ‘the fingerprint data’ to compare with the real or fake sample.
system based on an array of sensors/biosensors designs combined
with multivariate statistical data analysis, which is widely used as a Discrimination the Year of Ageing
rapid and reproducible quantitative and qualitative measurement. The The economic value of a majority of alcoholic beverages is highly
E-tongue imitates the human taste system, which is mainly composed associated with the years of aging. During the aging process, a series
of three parts: 1) sample preprocessor, which is equivalent to the taste of complex physicochemical reactions occur, such as oxidation,
receptor of taste cells in the oral cavity, to convert the features of liquid esterification, and hydrolysis, which increase the abundance and variety
sample into electronic signals; 2) sensors/biosensors array, which is of volatiles in alcoholic drinks. Therefore, the year of aging decides the
equivalent to the neural sensory system in the brain, which sensitively quality and flavor of alcoholic beverages. Some dishonest producers
captures the signals sent by the preprocessor and transmits it to the counterfeit their younger products as several years aged liquors to get
data processing system; 3) data processing and pattern recognition a higher selling price. Thus, the discrimination of the age of alcohol is
system. The E-tongue is equivalent to the central nervous system in essential to protect the benefit of consumers as well as the reputation
the brain, which uses multivariate pattern analysis models for the of the producers. E-nose, E-tongue, and a combination of them were
interpretation of screening data, including principal component analysis used to discriminate and classify wines according to the vintage year,
(PCA) and other analysis regression. recognize the method of aging, and monitor the aging process.
Detection of Spoilage and Off-flavors
The presence of unexpected off-flavors formed during fermentation or
storage is a great concern for alcoholic beverages, which largely impact
the quality and consumer acceptance of the products. The early
detection of these off-flavors is crucial to undertaking remedial actions
that can correct the fault. The E-nose is usually employed as a real-time
detection tool for quality control of alcoholic beverages. Beers and wines
were doped with off-flavor compounds such as acetic acid or sulfur
compounds; before that, the E-nose was used to analyze a variety of
samples to keep the data in a recognition system to evaluate the
components of the sample alcoholic beverages in a second. The off-
flavors can also be detected by E-tongues which have been used to
monitor the levels of acetic acid in various wines and beers. The E-tongue
system has been developed to distinguish samples based on permitted
3. Electronics Eye (E-Eye) The E-eye uses image sensors coupled levels of fault compound content.
with computer simulation criteria to discriminate or identify the sample These are some of the possibilities to apply intelligent sensory
color, shape, size, and other specifications. The measurement is technology to the quality checking of alcoholic beverages, which
performed with the use of software that creates color spectra with the overcome the current methods. However, IST still needs improvement,
indication of the size of their presence in the tested sample. E-eyes especially the development of high sensitivity and selectivity of the
allow complex sensory information to be processed. Combined with sensor arrays aimed at improving the accuracy and reliability of the
machine learning techniques, E-eyes develop models that learn from analysis.
a training data set and can fit complex functions between input
and output data, which may generate actionable information for
manufacturers. E-eyes have been used in the food industry for More Information Service Info C009
characterizing the components that contribute to sensory properties:
from ripening to harvest, from raw material to processed food products.
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