The Secret Behind The Pleasure Sensation of Food Products
Today, almost all food products you can find in the market contain flavor. Flavor is what gives food and drinks their magic and makes our sense of taste so precious. It is also the most important driver of food purchases, product loyalty, and demand from consumers.
What consumers demand now is not merely a 'good' taste anymore. They want more unique eating experience through various sensations that can stimulate their taste sensory such as fresh, cool, or warm sensations. This is why food flavor play an important role and their usage in foods have gotten serious attentions in the food industry.
What is flavor?
Flavor is the sensory impression of food, especially through taste and smell senses, that is influenced by the characters of food ingredients, texture, and appearance when foods are consumed i
Flavor compounds impart food aroma and taste, which are the major factors influencing consumer’s perception of the quality of food. Understanding the nature of flavor compounds and their effects on human organoleptic responses is important and flavor analysis is an inseparable part of the process
How to describe flavor?
As shown above, flavor can be classified as top note, which is the first impression/aroma that can be easily detected in less than 10 minutes, medium/heart note, which is the aroma that can be detected as signifying the first impression. Medium note is the binder between top note and bottom note. This aroma usually lasts up to 4 hours. Bottom note is the impression/aroma that can be detected as the aftertaste/profile of the flavor itself.
The characteristic of a flavor is usually determined by the volatiles in it. Both qualitative and quantitative analysis of these volatiles can be done by Gas Chromatography (GC). GC is the main choice of analysis for its ability to separate and analyse these volatiles by qualitative and quantitative. By the accurate configuration of GC (sample introduction, inlet system, column, detection system, library) and the right preparation technique, the outcome of the analysis is optimized to get the characteristics of flavors intended.
The components that give a flavor its particular characteristic might not always be the main component (with the highest concentration) in that flavor. There're lots of components at very low concentrations that give a flavor its main character, making it challenging to identify them in a sample as they have been coeluded in the sample's matrix. Thereby, the combination of human senses (olfactory) and Gas Chromatography Mass Spectrometer (GCMS) is an effective technique to analyse and characterize the flavor's components. Olfactory Detection Port (ODP) is an interface between GCMS and flavorists that enables flavorists to give a feedback to the instrument on the time of retention at which the flavor's components are detected at a particular intensity. Through GCMS-ODP technique, we can compare chromatogram and mass spectrum (Total Ion Chromatography/TIC) to further analyse the characterizing components (based on library search from GCMS) ii
Sample introduction of GCMS uses Dynamic Headspace (DHS) system, making the analysis of flavor's components to be more sensitive as compared to Static Headspace system. This is enabled by pre-concentration process in DHS system. The working principle of DHS is to extract flavor's components (volatiles) from a sample by heating at a particular temperature and time. The volatiles are then caught in the trapping system until an equilibrium is reached. The next step is heating of adsorbent in the trapping system through thermal desorption until that component is released and moved to GCMS-ODP system for sensory characterization through ODP and chemical analysis through Mass Spectrum. This DHS technique is applicable for both liquid and solid samples, usually directly without the needs of preparation iii
The output of DHS will then be put into the inlet system of GCMS. After column separation, the next process is the detection of flavor's components with Mass Spectrometry Detector (MSD). MSD detects ions based on molecular mass' intensity/charge numbers of ions or what's known as m/z iii
The technological advance of Mass analyzer today provides a few options according to different analytical needs, such as Single Quadrupole, Triple Quadrupole, Ion Trap & Quadrupole – Time of Flight (QTOF). Each of this mass analyzer has its own advantages.
The newest technology for the identification of unknown volatiles is GCMS with mass analyzer QTOF. Our current technological advance have enabled accurate and precise flavor analysis to provide an identification of flavor's characteristics intended.
The source of flavor raw materials is come from:
- Plants/parts of plants
Examples: spices (clove), herbs, fruits and vegetables
- Extraction products of raw materials through physical process: pressing, distillation.
- Chemical synthetics from isolates or natural products, such as vanillin from lignin
- Isolated or pure chemicals extracted from natural resources, such as eugenols from clove bud oils and citral from lemongrass oil
- Naturally identical synthetic chemicals
- Flavor enhancer/potentiator, such as MSG, Ribonucleotide (IMP, GMP)
- Artificials/synthetics produced in a laboratory such as ethyl vanillin, gamma undecalacton
Flavor Creation Mechanism
In food products, flavors are created through :
- Enzymatic process: the work of enzyme through metabolism of plants, animals, and microbes, both pre-harvest and post-harvest. Examples: spices, fruits and vegetables
- Non-enzymatic process: flavors are created through heating/other processes such as Maillard reaction, lipid degradation, caramelisation and process flavor or reaction flavor. Examples: chicken flavor, beef, bread, coffee and popcorn flavor
Purposes of flavor usage
- Impart a particular flavor other than that of the raw materials. Examples: cassava crackers, potatoes with hot, sweet, sour, beef, cheese and other flavors
- Enhance weak aroma or aroma of food products that is lost during processing.
- Flavor profile modification or masking unwanted flavor
- Seasonal flavor components and other factors
- Economical reasons
Based on its process, flavor can be categorized into three typesiV:
- Natural flavors: made from natural products that include:
- a) parts of whole plants such as spices and herbs
- b) products extracted from natural products such as essential oil, oleoresin, extracts
- c) mono chemicals isolated from natural's extracts such as eugenol from clove buds oil
- d) mono extracts gained by biotechnology
- Nature identical flavors: made from synthetic chemicals existing in nature
- Artificial flavors: synthetic flavors from chemicals non-existing in nature, such as ethyl vanillin. Vanillin is gained from vanilla plant. Ethyl vanillin has an intensity 3 times stronger than vanillin.
- Anon, Definition of flavor. Food Technol. 23, No. 11, 28.
- "Critical Mass: A History of Mass Spectrometry". Chemical Heritage Foundation. Retrieved 23 January 2015.
- Ferdian, 2015 Analisis flavor berbasis Mass Spectrometry, Berca
- Heath, H.B. 1978. Flavor Technology : Profiles, Products, Applications. AVI. Publishing company