Analysis of Capsaicin and Dihydrocapsaicin in Capsicum

Download PDF April 4, 2019

Introduction

capsaicin analysis
LC-4000 Series HPLC

The pungent components (which are responsible for the ‘hotness’) contained in the fruit of the genus Capsicum are collectively referred to as the Capsaicinoids. Capsaicin and dihydrocapsaicin in Capsicums constitute 80 – 90% of the pungent components; these compounds are now widely used in medical products and health foods.

It is known that the capsaicinoids are present in differing amounts in the various parts of the capsicum fruit. In this experiment the capsaicinoid content of the pericarp, seed and placenta from each of four types of capsicum was measured – Capsicum frutescens, Serrano, Finger hot and Habanero.

Experimental

Equipment

Pump:PU-4180-LPG
Column oven:CO-4061
Autosampler:AS-4050
Detector:MD-4010

Conditions

Column:CrestPak C18S (4.6 mmID x 150 mmL, 5 mm)
Eluent A:1% Acetic acid/Acetonitrile (50/50)
Eluent B:Acetonitrile
Gradient condition:(A/B), 0 min (100/0), 15 min (100/0), 15.05 min (0/100)
 20.00 min (0/100), 20.05 min (100/0) 1 cycle; 35.5 min
Flow rate:1.0 mL/min
Column temp.:40°C
Wavelength:280 nm
Injection volume:20 mL
Standard sample:Capsaicin 10, 50, 100 µg/mL in methanol
 Dihydrocapsaicin 10, 50, 100 µg/mL in methanol

Keywords

capsaicin, Dihydrocapsaicin, capsicum, pepper, Scoville Scale

Results

The chromatograms of 10 µg/mL each of Capsaicin and Dihydrocapsaicin standards are shown in Fig. 1. Good separation was obtained within 12 minutes. The sampling procedure of the actual samples is shown in Fig. 2.

Fig. 1 Chromatogram of Capsaicin and Dihydrocapsaicin standard
1: Capsaicin, 2: Dihydrocapsaicin 2µg each
Fig. 2 Sample Preparation

The chromatograms for each  of 4 types of capsicum are shown in Fig. 3. In Table 1 the Capsaicin and Dihydrocapsaicin content in each Capsicum sample (wet weight) are shown. It is known that the contents are very different depending on each part and for the all capsicum, Placenta part contains Capsaicin and Dihydrocapsaicin the most.

Fig. 3 Chromatograms of each of the four species of Capsicum measured. Table 1 shows the Capsaicin and Dihydrocapsaicin content for each sample (wet weight).

Table 1 Capsaicin and Dihydrocapsaicin content in each part of the Capsicum

SampleComponents in each sample [µg/g]
CapsaicinDihydrocapsaicin
Capsicum frutescens  
Pericarp154120
Seed713542
Placenta95407410
Serrano  
Pericarp7.644.47
Seed387229
Placenta1080644
Finger hot  
PericarpN.D.N.D.
Seed2.892.87
Placenta217160
Habanero  
Pericarp13443.2
Seed29792.5
Placenta87202750
N.D.: Not detected

Conclusion

It is well known that the amount of capsaicinoids present is very different depending on the part of the capsicum fruit and is also widely different between species; as seen here the placenta contains the majority of capsaicin and dihydrocapsaicin, followed by the seed and then the pericarp which may contain little or no capsaicinoids. This simple application demonstrates a reliable sample preparation combined with a routine chromatographic separation to determine the concentration of capsaicinoids.

About the Author

Masao Bounashita