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The intent of this undertaking was to analyze different chili Piper nigrums and hot sauces for their Capsaicin and Dihydrocapsaicin content but concentration was focused more on the analysis of different chilis than sauces. Samples of chilis were refluxed utilizing Ethanol as an extraction dissolver and sauces were untrasonicated utilizing Methanol. The infusions were filtered and analysed via Reverse stage HPLC-UV Vis technique.

A figure of experiments were performed to optimize the method that has been antecedently used for analysis of chili Piper nigrums. The first experiment conducted was to optimize the continuance of reflux clip required to obtain a good output of Capsaicin. Results showed that 1hr is sufficient for the extraction of Capsaicin. A assortment of chilli Piper nigrums and sauces were analysed so as to determine the hottest Piper nigrum. In general all samples had good sensing. Different parts of chilis were besides examined to set up which portion contains the highest concentration of Capsaicin and Endocarp was found to be the hottest portion. The duplicability of the method was besides investigated and the sample showed to hold a low RSD value.

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“ Following to Jazz music, there ‘s nil that lifts the spirit and strengthensthe psyche more than a good bowl of chilis. ”Harry James ( Late American instrumentalist )Loved by 1000000s for their hot and sizzling spirits, the chili Piper nigrums have become really popular over the period of clip and are being grown in about in all parts of the universe, with Asia being the biggest manufacturer of chilis followed by Mexico and the U.S.In traditional Indian medical system, chili is used as manner of exciting the digestion and is besides believed to be a natural hurting slayer.The ruddy chili Piper nigrums are besides a beginning of K, Mg and Fe and vitamin C.

1.1 Why Are They So Hot?

The ‘heat ‘ esthesis in chilis is caused by a category of chemicals, called the Capsaicinoids. These compounds are found in members of the capsicum household of workss. Capsaicinoids themselves belong to a group called ‘Vanilloids ‘ i.e. incorporating the Vanillyl group [ ]Figure 1.

1 [ ]All Capsaicinoids have same functional groups and differ merely in length of hydrocarbon concatenation. The most common of Capsaicinoids compounds is ‘Capsaicin ‘ which is the major component of chili Piper nigrums and besides responsible for their acrid gustatory sensation.

[ 3d chem. ]

1.2 Structure of Capsaicins:

Capsaicin figure 1.


Dihydrocapsaicin figure 1.2.2

Nordihydrocapsaicin figure 1.2.3

Homocapsaicin figure 1.2.4

Homodihydrocapsaicin figure 1.


Out of all the Capsaicins, the capsaicin and dihydrocapsaicin are the major components of Capsaicinoids ( do up 80-90 % of capsaicinoids ) .

1.3 Cis-trans isomerism in Capsaicin [ 3dchem ]

Capsaicin can exhibit cis-trans isomerism due to the presence of C=C bond.

The dual bond prevents the molecule to revolve freely internally, hence, giving rise to stereo isomers.Cis isomer of the capsaicin is less stable and has higher energy due to steric hinderance. As the methyl groups are in close propinquity to each other it causes repulsive force between them and therefore doing it a less stable agreement due to this added strain.Trans isomer on the reverse has methyl groups further apart and does n’t hold any steric hinderance, doing it a more stable/low energy agreement.

Therefore, the Capsaicin is ever found in the Trans isomer.

Figure 1.3.1 [ hypertext transfer protocol: // ]

1.4 Scoville Scale

The graduated table for mensurating the extent of heat in chilis was foremost invented by an American Chemist Wilbur Lincoln Scoville in 1912.

The trial he devised is known as the ‘Scoville Organoleptic trial ‘ in which he had a group of voluntaries to savor the chilis on their ain and subsequently diluted them with sugar and H2O until they did n’t hold any firing esthesis left. The ensuing dilution factor was called the ‘Scoville heat value ‘ of the sample and a figure was so assigned to each sample of chili i.e.

Scoville unit, to determine the sum of dilution a chili needs before it ‘s hot flavour dies off. [ 3d.chem ]

Table 1.4.1 Scoville heat values for Capsaicinoids [ ]

MoleculeStrength /Scoville unitsCapsaicin16.1 millionDihydrocapsaicin16.

1 millionNordihydrocapsaicin9.3 millionHomocapsaicin6.9 millionHomodihydrocapsaicin8.1 millionThe hottest capsaicin found is in the chili known as ‘Naga Jolokia ‘ , grown in India and has Scoville strength of 855,000-105, 0000 units. The Habanero ( Mexican chili ) are the runners-up with Scoville evaluation scope of 200,000-300, 0000. g6csy.

netAs mentioned earlier, in add-on to Capsaicins being used as nutrient additives, they have of import medicative benefits and are known as ‘Phytochemicals ‘ . [ ] Due to holding pharmaceutical and antioxidant belongingss, it ‘s widely used in anti-flammatory picks and unctions and besides used as a counter thorn in surgical dressings and medical specialties. Furthermore, they are besides being used in nutritionary addendums for hurting alleviation and Arthritis. [ ]


5. Extraction Methods for Capsaicin

Different methods have been devised as a manner of pull outing capsaicin from chilies and sauces. The simplest technique is to fade out chilies in a polar dissolver and puting the mixture on hot home bases for half an hr and so filtrating the infusion via simple/vacuum filtration and doing up with Methanol ( 100 milliliter ) .The other techniques more efficient for extraction are as follows:

1.5.1 Solid Phase Extraction or SPE

This technique is peculiarly utile in pull outing capsaicin as it requires pre-treating the sample prior to analysis.

This reduces the sum of unwanted constituents that may interfere with the analysis.The extraction is completed in 4 stairss:Conditioning the cartridge: This involves triping the cartridge by go throughing the sample through it to accomplish same conditions with in the cartridge ( e.g.

to accomplish same pH, composing etc as the sample ) .Retention: The sample is applied to the cartridge and either contaminations are retained and analyte is flushed through the cartridge. Other manner used is keeping the analyte with in the column and the unwanted constituents are passed through the column.Rinsing: The cartridge is so rinsed with distilled H2O to rinse off the drosss.Elution: The last measure is to elute the sample with appropriate dissolver and the infusion can so be used for analysis.

1.5.2 Reflux

As demonstrated in this undertaking, this method involves refluxing the chilies in methyl alcohol for appropriate continuance. The reflux clip required can be optimized by refluxing samples for different continuances to set up the optimal clip required by the capsaicin to leach.

1.5.3 Ultrasonication

This method can be used for pull outing the capsaicin from sauces or capsaicin based picks in short clip.

The samples are soaked in Ethanol and placed in the supersonic bath for half an hr at high temperature. The supersonic quivers release the capsaicin from the samples.


4 Supercritical fluid extraction or SCFE

In this method, the extraction dissolver used is a ace critical fluid. A ace critical fluid ( SCF ) is a compound above its critical temperature and force per unit area. Therefore, an SCF is neither a liquid nor a gas. Hence, a ace critical fluid has belongingss similar to liquids i.e. fade outing compounds and besides gas like belongingss e.g. transit.

SCFE besides minimizes the matrix constituents. Due to these capablenesss, this method is more efficient and quicker than the other extraction methods. Carbon dioxide and H2O are the most normally used SCF. This technique has a assortment of applications in nutrient, gasoline, and pharmaceutical industries.

1.6. Previous research on Capsaicin

Capsaicin has been widely studied and researched by assorted administrations and establishments but deficient literature has been published with regard to the analysis of chili Piper nigrums and sauces. In this subdivision, three articles will be discussed as all three documents deal with the analysis of chilis and sauces relevant to this undertaking.

The first literatureA? investigated the concentration of Capsaicin and Dihydrocapsaicin in the Habanero Piper nigrums utilizing Super Critical Fluid Extraction method ( SCFE ) . In add-on to the analysis of Habanero whole Piper nigrums, different parts of chili were besides examined for their Capsaicin content. The Habanero Piper nigrums were obtained from two different locations: Cunningham Research station and Bailey Farm ( located in North Carolina, US ) .The Piper nigrums were cut into seeds and shells and anterior to extraction, the samples from Bailey farms were prepared fresh, oven dried and freezing dried and samples from Cunningham station were prepared in oven and freeze dried provinces.

The whole Piper nigrums and seeds/shells samples were extracted utilizing three polar dissolvers i.e. Methanol, Acetone and Acetonitrile.

The Method for SCFE is every bit follows as stated in the literature: “ Fresh, oven and stop dead dried readyings ( 0.5g dry weight ) were extracted utilizing a biomass: solvent burden of 15 % ( w/v ) based on the initial wet of the Piper nigrum samples/parts. Sample and solvent mixtures were homogenised in 50ml conelike glass tubings and placed in a shaking H2O bath ( 50°C ) . ” The infusions ( 2ml each ) were so filtered and stored at -20°C until the analysis.The preliminary work suggested that 1hr is sufficient to acquire good output of capsaicin.

The infusions were so analysed utilizing Reverse-phased HPLC with UV VIS Detector. The HPLC was equilibrated with capsaicin criterions ( 10, 30,50ppm ) . The nomadic stage composing was isocratic at 60:40 ( Acetonitrile: Water with acetic acid ( pH 3 ) ) .The research workers of this undertaking compared the capsaicin and Dihydrocapsaicin concentrations from both locations. The consequences showed that the Cunningham station ‘s Piper nigrums had higher concentration of capsaicin in comparing with the Bailey farm ‘s chilis but the Bailey Farm ‘s Piper nigrum had higher sum of Dihydrocapsaicin than the Cunningham ‘s. The consequences suggested that samples that were oven dried and extracted with Acetone gave maximal outputs of the Capsaicinoids. This literature besides suggested that regardless of the dissolver type and readying province used, seed has the highest sum of capsaicin.The research workers suggested the ground for differences in capsaicin concentration was due to different environments the fruits are cultivated e.

g. chemicals used, upwind conditions etc.The 2nd literatureA? trades with the analysis of three Capsaicinoids i.e. degrees of capsaicin, dihydrocapsaicin and nordihydrocapsaicin in different chilis, sauces and arthritis picks via contrary phased HPLC. This research employed a solvent extraction technique which involved add-on of ethyl alcohol ( extraction dissolver ) to the samples of land chilis, sauces and picks and puting the samples on hot home bases for 30mins.

After chilling and filtration, the infusions were transferred into flasks ( 100ml ) and made up to the grade with Ethanol. 5ml was withdrawn from this sample and filtered once more into a syringe filter cartridge ( 0.45Aµm pore size ) . This aliquot was so used for the analysis. A 1000ppm standard stock solution was used to do standard capsaicin solutions runing from 1-50ppm and ran through HPLC. The nomadic stage in this research was made up of ACN, H2O and phosphorous acid ( 0.

1 % ) .The UV sensor was set at 280nm and 205nm to find samples responses at different wavelengths. In add-on, Isocratic and Gradient elution were used.The findings from this diary suggested that Capsaicinoids nowadays in really small concentrations ( e.g. 0.

5ppm ) were detected better at 205nm wavelength utilizing gradient elution instead than Isocratic method. However, consequences besides indicated that for analysis of Capsaicinoids nowadays in greater concentrations, Isocratic elution and UV wavelength at 280nm. The concentrations of the Capsaicinoids were expressed in footings of the Scoville units and the value calculated for the Habanero Piper nigrums ( 150,000 ) in this experiment was different to the literature value scope ( 200,000-300,000 ) . The research workers attributed this fact to fluctuations in the environment e.g. conditions etc.The 3rd literatureA? determined the capsaicin and dihydrocapsaicin content in chilli Piper nigrums.

The chilis were grounded for 10mins and Acetonitrile ( 30ml ) was added to the crushed Piper nigrums and once more grounded for 20mins. The solid residue was filtered and an aliquot ( 1ml ) was made up to the grade with Acetonitrile. ( in 10 milliliters flask ) .The extraction method used in this work was Solid Phase Extraction ( SPE ) : An SPE cartridge was conditioned with Acetonitrile, methyl alcohol and H2O and the capsaicin infusion ( 10ml ) was so applied to the cartridge and the analyte was eluted with methyl alcohol ( 4ml ) and so once more with 1 milliliters of methyl alcohol ( incorporating 1 % acetic acid ) .The analytes were so run through contrary stage HPLC utilizing UV-VIS sensor ( at 281nm ) ; nomadic stage consisted of 77:33 ( Methanol: Water ) . The HPLC was eluted foremost with the criterions so as to obtain the standardization graphs.

The Capsaicinoids concentration of different chilis was expressed in Scoville heat units ( similar to literature 2 ) . The consequences showed that Habanero is the hottest amongst all Piper nigrums that were analysed i.e. Scoville heat value of 276,000 which corresponded to the literature value scope.

The least hot Piper nigrum was Jalapeno ( 41,000 Scoville heat units ) .

1.6.1 Comparison of three documents:

The researches have used different techniques to pull out the Capsaicinoids i.e. SCFE and SPE. However, the extraction technique used in this undertaking was Reflux ( for chilis ) and Ultrasonication ( for sauces ) . The extractions were successful and all samples in general were detected which indicates that more than one method can be employed as a manner of pull outing the Capsaicinoids from chilis and sauces.

Assorted parametric quantities were manipulated as portion of method development in literature 2 e.g. Isocratic/gradient elution and different wavelengths. Similarly in Literature 1 three readying provinces and three dissolvers were used to find what state/solvent gives maximal output of Capsaicinoids.

Literature 1 besides suggested that the hottest portion with in the chili is the seeds, nevertheless, the findings of this undertaking have shown that the Endocarp contains the highest sum of capsaicin and dihydrocapsaicin. This is declarative of the fact that the sum of Capsaicinoids can change even with in different parts of chili. However, all researches discussed every bit good as this undertaking has used polar dissolvers to pull out the analytes and the analytical technique used was rearward stage HPLC which indicates it ‘s usefulness in the capsaicin analysis in peculiar.Once an analyte of involvement has been extracted, it can be analysed by a procedure called Chromatography.

1.7 Chromatography

The word Chromatography originates from Greek ; Chroma means coloring material and graphein implies to compose. [ Skoog West Analytical Chem 7th Edition page 646 ]The history of this separative technique day of the months back to early 20th century when it was developed by a Russian Botanist Mikhail Tswett in 1903 [ D kealy Instant notes ] . He used this method for separation of assorted works pigments and samples were passed through a Ca carbonate column. The detached analytes were identified as they left colored sets on the column. [ Skoog West Ana Chem 7th Page 646 ] . Since its innovation by the Russian Scientist, this method has been modified and developed in many signifiers to give quantitative ( sum of the analyte nowadays ) and qualitative analysis ( designation of the terra incognitas ) of complex mixtures. [ d.

Kealey instant notes page 119 ] .Separation in Chromatography is achieved by go throughing the sample mixture through the stationary stage by uninterrupted flow of a nomadic stage. This procedure is known as Elution. Hence, the chromatographic separation depends on the differences in the distribution ratios of the sample constituents between the stationary and nomadic stage.

Therefore, this capableness of an analyte to migrate at different rates in both stages gives separation over a period of clip and distance travelled. [ D Kealey page 120 ]Kx= Cs/Cm, where kx is the equilibrium divider coefficient and Cs and Cm are molar concentrations of analyte in Mobile and stationary stage.There are two types of Chromatography techniques: Year 2 notes page 25-26

1.7.1 Planar Chromatography

In this method, the stationary stage is composed of a level bed of stuff which is made up of an adsorbed bed distributed equally over a sheet of glass, plastic or Aluminum ( known as Thin Layer Chromatography or TLC )Paper Chromatography is besides another type of Planar Chromatography in which the stationary stage is a sheet of cellulose stuff.

1.7.2 Column Chromatography

In this method, the stationary stage is a glass or metal column on to which the stationary stage is tightly packed onto a column where separation takes topographic point.

Examples of Column chromatography are Gas Chromatography, High Performance Liquid Chromatography etc.


3 Chromatogram

The secret plan of sensor response Vs elution clip is known as the Chromatogram. [ Year 2 notes page 25 ] .Figure 1.7.3.

1 [ hypertext transfer protocol: // ]

1.7.4 Retention clip

In the above figure is a typical chromatogram and term tr is the clip taken by the analyte to elute the column, known as Retention clip. [ twelvemonth 2 notes page 28 ]


4 Dead clip [ vitamin D Kealey page 121 ]

Indicated as thulium in the fig is referred to the dead clip this is defined as “ the keeping clip required by the non retained species ( i.e. nomadic stage molecule ) to go through through the column.

”A good Chromatogram should hold good defined extremums holding right form and symmetricalness ( i.e. Gaussian form ) , eluted in sensible keeping clip ( tr non excessively long or excessively short ) and should be separated from the immaterial extremums. [ Year 2 notes page 29 ]

1.8 Describing a Chromatogram

There are four parametric quantities used in chromatography that evaluate the quality of a chromatogram. These are:

1.8.1 The Capacity Factor, K ‘

It is the sum of nomadic stage required to elute a peculiar extremum.

The K ‘ is calculated for the first and the last extremum. This factor is peculiarly utile when set uping the best nomadic stage composing in the HPLC.K ‘ can be calculated as followers:K’= ( tr-tm ) /tm wheretr is the keeping clip and thulium is the dead clip.

A Chromatogram holding good separated extremums in good keeping clip will hold K ‘ values between 2-8.

1.8.2 The Selectivity Factor, I±

This is the ability of a system to divide two analytes ( A and B ) and is calculated by:I±= trb – tm/ tra- thulium, wheretrb and tra are the keeping times of analytes A and B.A system where extremums are clearly separated has a value of I± & gt ; 1


8.3 The Resolution factor, Rs

This determines the ability of a system to decide two extremums that elute really near to each other. And can be calculated by:Rs = 2 ( trb-tra ) /Wa+ Wb wheretra and trb are keeping times and Wa and Wb are the peak breadths of analyte A and B.The value of Rs & gt ; 1.

5 for a good quality chromatogram.

1.8.4 The Efficiency Factor [ D kealey page 126-127 ]

When separation takes topographic point in a column, the chromatographic separation can be evaluated by the declaration factor, Rs or the efficiency factor. The efficiency is defined as the figure of theoretical home bases in a column. This factor evaluates the extent of set widening of the analyte extremums. Increasing the figure of home bases and cut downing their highs gives better efficiency and frailty versa. The home base tallness can be calculated utilizing:H= L/N whereL is the length of the column ( in mm normally ) and N is the figure of home bases.

The efficiency factor N is calculated by:N= 16 ( tr/W ) A? for a extremum with a good baselineN= 5.54 ( tr/W1/2 ) A? for a extremum with a hapless baseline and W1/2 is the breadth at half the maximal tallness of the extremum. ( twelvemonth 2 notes 42-43 )

1.8.5 Band Broadening

As an analyte passes down a column, the extremums become shorter and broader due to assorted factors that cause set widening. The Van Deemter Equation explains the ground for the set widening:H= A+ ( B/u ) + Cu where H is the home base tallness and U is the additive speed of the nomadic stage. Other variables in the equation are explained below:A- Eddy Diffusion: As the nomadic stage carries the sample constituents through the stationary stage, some constituents pass through the column in a consecutive line whilst other may that are retained longer by the stationary stage may divert from the consecutive way and do the extremums or sets to be broader.

If equally sized atoms are used for packing the stationary stage, so the Eddy diffusion can be minimized.B- Longitudinal Diffusion: If the nomadic stage is going at low speeds, so the analyte will pass more clip in the column as analytes diffuse into the nomadic stage. This longitudinal diffusion contributes towards peak widening and can be minimized by an increasing the flow rate of the nomadic stage. The increased speed will cut down the keeping clip ensuing in reduced effects caused by this phenomenon. [ Veronica HPlc page 17-19 ]C-Mass transportation: As discussed earlier in this subdivision, the separation depends on the ability of the analyte to administer itself between the stationary and nomadic stage. As the nomadic stage is invariably fluxing, the true equilibrium distribution of the analyte is ne’er established. This leads to increased keeping times and therefore ensuing in extremum widening.

[ 500 kealey page 124 ]

5. High Performance Liquid Chromatography or HPLC

HPLC is a signifier of liquid chromatography which provides both qualitative and quantitative information about complex mixture samples in short clip. The stationary stage in this technique is made up of really little all right atoms and the sample is forced through the column by nomadic stage dissolvers under high force per unit area, hence besides bearing the name High Pressure Liquid Chromatography. [ page 1 Veronica HPLC ] .

5.1 Mobile stage in HPLC

The chief demand for this technique is that the analyte must be soluble in the nomadic stage as the nomadic stage carries the sample mixture through the column where separation takes topographic point. Therefore, if the analyte interacts with the nomadic strongly, it will elute the column faster, taking to shorter keeping times. [ page 66 Chromatographic separations ] .

The nomadic stage can either be a individual dissolver or different dissolvers combinations may be used. After suited nomadic stage has been chosen, the system can be set at isocratic or gradient conditions. In Isocratic conditions, the chosen ratio of dissolvers remains changeless throughout the analysis e.g. in this undertaking Isocratic Mobile stage used for analysis.

In contrast, the gradient nomadic stage can be changed over the period of clip. [ Year 2 notes ] .

1.9 Stationary stage in HPLC

The stationary stage in HPLC consists of a solid made out of micro porous stuff packed into the metal column. Silicas or modified Silicas with nonionic organic groups attached are normally used as column packing stuff. Out of all stationary stages used in HPLC, Octadecyl silica known as ODS or C18 is most extensively used due to its ability to divide the analyte constituents with high, intermediate and low mutual oppositions.

Other stationary stages used in HPLC are Aminopropyl, Nitile, Sulphonic acid, quaternate Amines etc [ d. kealey 159-161 ]Elution in HPLC is carried out by finding the extent of interactions of the analyte with the stationary and nomadic stages. The grade of separation of the sample constituents depend on their migration rates and distribution ratios in both stages.


9.1 Normal and Reverse stage HPLC

In normal stage HPLC ( surface assimilation chromatography ) , the stationary stage is more polar than the nomadic stage which is decrepit polar. The separations are based on the comparative mutual oppositions of the sample constituents. For case, if species A is more polar than the species B, A will hold strong affinity for the stationary stage and will be held in the column longer. This will ensue in species A holding long keeping clip compared to B.

Thus, in normal stage HPLC, least polar analyte elutes foremost.In Reverse stage HPLC ( bonded stage chromatography ) , the stationary stage in non polar and the nomadic stage dissolvers used are polar. This stage is governed by the hydrophilic and hydrophobic belongingss of the analytes. Most polar analyte elutes foremost and frailty versa.As Capsaicinoids are comparatively non polar, hence, if the nomadic stage mutual opposition in rearward stage is increased so the analyte will hold stronger affinity for the stationary stage and hence will pass more clip in the column, taking to long keeping times.

The nomadic stage dissolvers used in Reverse stage HPLC are H2O or aqueous buffer with an organic dissolver. The usage of protons in nomadic stage composing improves the peak form and travels in column rapidly.[ hypertext transfer protocol: //ionsource.

com/tutorial/chromatography/rphplc.htm # Solvents ]

1.9.2 HPLC Instrumentation

Figure 1.9.

2.1 [ hypertext transfer protocol: // v=I-CdTU5X4HA ]Pump: In HPLC dissolver bringing system, the pump is used to present the nomadic stage dissolvers to the column under high force per unit area. Most normally used pumps are ‘reciprocating pumps ‘ . The pumps used should be free of corrosion, must provide an accurate and controlled flow rate and should be pulse free.

The HPLC dissolvers for nomadic stage must be degassed to guarantee they are pure and free of any contaminations. This is done by go throughing an inter gas through the solvent reservoir in vacuity degasser.Injector: The sample is injected through syringe into the injector port. The injection system must non disrupt the flow of nomadic stage and should present sample into the column in little volumes ( 5-500AµL ) .Column: Most normally used HPLC column is 25cm in length, internal diameter of 4-6mm and particle size of 5Aµm.

1.9.3 Detectors in HPLC

When the sample constituents elute the column at different rates, they pass through the sensor, and the information signifier the sensor is so displayed in the signifier of a chromatogram.

1.9.4 UV-Vis Detector

The sensor is set at a specific wavelength which will be absorbed by the analyte. The grade of optical density of UV radiation by the analyte is relative to its concentration. ( Beer Lambert jurisprudence )

1.9.5 Diode array Detector or DAD

The Diode Array sensor is a type of UV Vis Detector [ D Kealey page 162 ] . When the sample reaches the detector cells, UV radiation is shone on the analyte.

The light beginning largely used is a Deuterium lamp. After light base on ballss through the cell, it ‘s dispersed onto the light-sensitive rectifying tubes via diffraction grate or quartz prism. Every rectifying tube in the array detects different wavelengths. The step of differences in extent of optical density at different wavelengths by the sample constituents consequences in their designation and besides gives information about the concentration of the analytes. [ hypertext transfer protocol: //www. ]Other sensors used in HPLC are Fluorescence, refractile index, electrochemical sensors etc. [ 500 Kealey 163-165 ]

Figure 1.


Experimental Method

This undertaking was performed in four different experiments. In all experiments, the methods for pull outing the capsaicin from chili Piper nigrums and sauces were the same i.e. reflux and Ultrasonication. However, different multitudes of chili Piper nigrums, their single parts were used and solvent volumes were taken in these experiments. ( see consequences )


1.1 Preparation of chili samples and extraction

Several chilis were cut into little pieces and weighed into a 250 milliliter unit of ammunition underside flasks. Ethanol ( 75 milliliter ) was so added to chilis. A capacitor ( fitted with gum elastic tubing to the H2O pat ) was fixed to the unit of ammunition underside flask and solution was placed on isomantle ( set at 80°C ) and refluxed in fume closet. After chilling off, infusion was filtered into 100ml flask and made up to the grade with ethyl alcohol. A 5ml aliquot was withdrawn into 1.

8ml sample vial utilizing a 0.45Aµm syringe filter. These aliquots were so analysed through HPLC.


2 Preparation of chili sauces and extraction

The hot sauces were prepared by dilution of sauce ( 2g ) with ethyl alcohol ( 15ml ) in beakers and solutions were topographic points in supersonic bath ( set at 60A°C ) for 30 proceedingss. The infusions were filtered in the same manner as chilis i.e. utilizing 0.

45Aµl syringe and transferred to 20ml volumetric flasks and conveying up to the grade with methyl alcohol.The equipment used was white tiles, knife, weighing boat and weighing graduated table.

2.1.3 Preparation of glasswork

In analytical experiments, it ‘s of premier importance to guarantee the glasswork used is clean.

Therefore, the glasswork used in this undertaking was washed foremost with deionised H2O and so with the dissolvers used.

2.1.4 Preparation of criterions for Calibration

The standard solutions were prepared from 200ppm stock solution straight into sample phials.

Eppendorf pipette was used for truth and 0, 20, 40, 60, 80, 100 ppm criterions were made with HPLC criterion Methanol.Concentration/ppmVolume of 200ppmCapsaicin/ I?LVolume of methanol/I?L00100020100900402008006030070080400600100500500

2.2 HPLC

The HPLC used in the research lab was Agilent 1100 SeriesColumn- ODS hypersilUV VIS Detector- G1315B Diode array sensor ( set at 280nm )Flow rate- 1.3 ml/minWindows XP CPUMobile phase- Isocratic at 65:35 Acetonitrile ( 2 % acetic acid ) : H2OParticle size- 5Aµm, Column dimension- 250mm ten 4.6mm


3 Determining I»max for UV- Vis sensor

The I»max for the sensor was determined by puting methanol space in UV spectrometer ( Perkin Elmer with lambda 40 ) to graduate it. After standardization, a 100ppm capsaicin criterion was placed in the spectrometer and a graph was obtained with the optimal wavelength ( see Appendix 1 ) . This was 280.40nm and the HPLC sensor was set at this wavelength.

2.4 Determining optimal nomadic stage composing ( see Appendix 2 )

The nomadic stage was altered to different ratios to set up what ratio gives the best separation and sensible keeping times ( less than 7 proceedingss ) . The 80:20 ratio ( MeCn: H2O ) gave shorter keeping clip but the extremums were eluted closer to each other. The 70:30 ratio showed good keeping clip but extremums were still closer to each other.

50:50 ratio gave long keeping clip and 60:40 ratio gave good separation but keeping clip was longer. Therefore ratio of 65:35 was used as this gave the best keeping clip and separation of extremums.

2.5 Determining Dead clip, thulium ( see Appendix 3 )

Uracil in methyl alcohol was used to mensurate the dead clip. The clip it took to go from column to the sensor was 2.166 proceedingss ( dead clip )

3. Consequences


1 Calibration graph 1 for green chilis ( see Appendix 4 )

Standard/ppmCapsaicin/ppmDihydrocapsaicin/ppmVolume of 200ppm capsaicin/I?LVolume of Methanol/ppm00001000201371009004026142008006039213007008052284006001006535500500



Standard/ppmRetention time/minPeak countryRetention time/minPeak country00000203.9876.84.8545.1403.98169.




3.2 Experimental Results for Optimisation method ( see Appendix 5 )

Green chilis were used to find the optimal reflux clip.



Reflux time/hrMass/gPeak AreasAverage Area[ Concentration ] / mg/gPeak AreaAverage Area[ Concentration ] / mg/g1 hour1 hour10.0231.534.132.80.075210.212.

211.20.04422 hour2 hour2 hour10.


0361A? hourA? hour10.0134.333.333.80.

077515.710.613.150.0519The half hr and one hr refluxed samples were refluxed once more for another 3 hours to look into if any capsaicin is left. Analysis showed that no capsaicin was detected for fruther reflux. ( see Appendix 6 )The 2hr refluxed sample could non be refluxed once more as the flask was by chance broken.


2.1 Calculating the concentration from standardization graph

The concentration in mg/g was calculated by the equation displayed on the graphs i.e. y = maxwell, where Yttrium is the mean peak country of the multiple injections of the same sample.X= y/m gives concentration in ppm, the concentration in ppm was so multiplied by the volume in dm3 and so divided by the mass of sample in gms. e.

g. y = 4.3547xten = 33.8/4.3547 = 7.76 ppm[ 7.76 tens ( 100/1000 ) ] / 10.

01 = 0.0752 ( capsaicin concentration for half hr sample )

3.3 Calibration Graph 2 ( see Appendix 7 )

CapsaicinDihydrocapsaicinStandard/ppmRetention Time/minPeak AreaRetention Time/minPeak Area00000404.02198.64.90139.




3.4 Analysis of 6 different types of chilis

Concluding volume of the infusions: 0.


3.4.1 Consequences for Naga ( see appendix 8 )



ChiiliMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gNaga20.031417.71413.31415.


3.4.2 Consequences for Small Green ( see appendix 9 )



ChiliMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gSmall Green20.



3.4.3 Consequences for Bullet ( See Appendix 10 )



ChiiliMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gBullet20.02102.187.3494.720.094662.3054.2558.280.100

3.4.4 Consequences for Bird Eye ( see Appendix 11 )



ChiiliMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gBird oculus20.021148.51121.821135.21.13442.24424.23433.240.7457

3.4.5 Consequences for Red Long chili ( see appendix 12 )



ChiiliMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gRed Long20.0390.1583.7386.940.086873.1368.2070.670.1216

3.4.6 Consequences for Long Green chili ( see Appendix 13 )



ChiiliMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gLong Green20.02148.17147.25147.710.14890.4979.7585.120.147

3.5 Consequences for different parts of chilis

Two different types of chilis were analysed to find the hottest portion with in the chili. The volume used for both chilis was 0.025dmA?

3.5.1 Consequences for Bird oculus parts ( see appendix 14 )



Chilli portionMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gSeed5.01483.5458.37470.940.47194.75181.23187.990.323



Chilli portionMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gStone5.013190.53408.53299.53.291217.021374.711295.872.23



Chilli portionMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gtegument5.01211.39218.13214.760.21484.5482.1583.350.143

3.5.2 Consequences for normal green different parts ( see appendix 14 )



Chilli portionMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gStone4.172558.62421.62490.12.991395.691307.181351.442.792



Chilli portionMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gSeed4.17280.45302.18291.320.349157.65152.83155.240.321



Chilli portionMass/gPeak AreasAverage AreaConcentration /mg/gPeak AreaAverage AreaConcentration/mg/gSkin4.18375.05332.27353.660.423185.32169.40177.360.366

3.6 Consequences for duplicability ( see appendix 15 )

Naga chili sample was analysed for duplicability of the method. Seven injections from the same sample were injected.The duplicability for the capsaicin gave an RSD value of 1.995 % . RSD for dihydrocapsaicin was besides calculated and value was 2.25 % . Ratios of Cap/DHcap were besides calculated the RSD was 3.47 %

3.7 Consequences for sauces ( see Appendix 16 )

Four sauces were analysed. The volume of the infusions were 0.02dmA?



SaucesMass/gPeak AreasAverage Area[ Concentration ] / mg/gPeak AreaAverage Area[ Concentration ] / mg/gSrichara2.0132.6713.1622.950.045713.204.278.740.0300Habanero2.0111.2969.7840.540.08073.5217.2410.380.0356Mr Naga2.0291.260.18118.040.0615Maggi2.0143.4763.5453.510.10724.3636.2730.530.105

4. Discussions

The first experiment performed was to analyze the optimal reflux clip required to pull out capsaicin. Consequences showed that the sum of capsaicin leached for half an hr was about the same as concentration of capsaicin extracted in 1 hour. Therefore, half hr is sufficient for refluxing the chilis. In the experiments all chilli samples were refluxed for 1 hr to guarantee maximal capsaicin is extracted.The analysis of 6 different chilis showed that Naga chili was the hottest chili followed by Bird Eye chili. It was interesting to see that the long green and ruddy chili had the least sum of capsaicin so can be classified as mildly hot.The analysis of different parts of chilis showed that Endocarp is the hottest portion for both chilis. Bird oculus chili had seed more concentrated in capsaicin than the tegument. However, for normal green chili, the tegument was hotter than the seed which shows that even with in the different parts of Piper nigrum, the sum of capsaicin may change.The duplicability method showed that consequences are consistent as the RSD values calculated were low overall.Mr Naga was the hottest sauce analysed followed by Wise Men.

5. Possible Further Study

For farther surveies, different methods for pull outing capsaicin can be analysed to look into what method gives the best efficiency. Different methods proposed are Solid Phase extraction and Supercritical fluid extraction.

6. Decision

From the consequences it can be concluded that the extraction methods used in this undertaking were successful and rearward stage HPLC is a good technique to mensurate the sum of capsaicin in chilis and sauces.Calibration graph 1 was non as additive so great attention was taken when doing criterions for standardization graph 2. Graph 2 was additive and showed good quality preciseness. The RSD values calculated were low overall, which indicated the consequences are consistent.In General UV sensor detected all samples.

7. COSHH hazard appraisal

Sigma Aldrich web site was used for jeopardy labels and hazard. Lab coat and goggles were worn at all times. Baseball gloves were besides worn when managing chilis.