Syntax
Literate: Jurnal Ilmiah
Indonesia p–ISSN: 2541-0849 e-ISSN: 2548-1398
Vol. 9, No.
12, Desember 2024
IDENTIFICATION
OF VOLATILE COMPOUNDS IN SOY MILK DRINKS USING SOLID PHASE MICROEXTRACTION-GAS
CHROMATOGRAPHY-MASS SPECTROMETRY (SPME-GC-MS)
Aisah Kensar Nawang
Wulan Sari1, Dedi Hanwar2*
Universitas
Muhammadiyah Surakarta, Indonesia1,2
Email:
[email protected]1, [email protected]2*
Abstrack
The distinctive aroma produced by soy milk is
thought to come from volatile compounds. The development and use of soy milk
derivative products require a deep understanding and characterization of the
flavor profile. The aim of this study was to identify volatile flavoring
compounds found in soy milk made from imported and local soybeans. Milk samples
extracted using the headspace-SPME method at a temperature of 60°C for 20 minutes,
and analyzed using GC-MS. The results obtained, detected as many as 23 major
volatile compounds (relative levels> 1%) in both samples. The difference in
total volatiles produced between the two samples showed that there was a
significant difference (P <0.05), while the difference in relative levels
between compounds that often appear such as pentanal in both samples showed
insignificant results (P> 0.05). It can be concluded that the origin of
soybeans between imported and local soy milk influences the total amount of
volatile compounds identified, however, it does not significantly influence the
flavour and aroma characteristics caused by the
pentanal compound.
Keywords: Volatile Compounds; Soy Milk; SPME; GC-MS
Introduction
Soybeans are the most important seeds in the world
because they are widely marketed in the form of
original seeds and in the form
of by-products whose processing is widely used
in various industries. Soybeans are famous for their high
protein content of 40% to 41%. Apart
from its high protein content, soybeans also contain
35% carbohydrates, 8% to 24% oil,
and 5% ash
Breaking the soybean shells during processing into soy milk
products will activate the presence
of the lipoxygenase
enzyme. This enzyme reacts with
fat and produces
volatile compounds such as glucosides (causing
a chalky taste), saponins (causing bitterness), and
the main compound in soy milk, hexanal,
which can cause a beany flavor.
The process of making soy milk will
activate these volatile compounds
The Solid Phase Microextraction (SPME) technique is a solid extraction method for gas chromatography analysis using the principle
of polymer-coated fibers used as an extraction tool.
The extracted analytes can be directly
analyzed using gas chromatography without the use of
solvents that can contaminate the sample
The composition profile of volatile
compounds in soy milk can vary.
This is due
to several factors including differences in soybean origin, soybean varieties, soil conditions, climate and cultivation
methods which will influence the color, chemical
composition, flavor and sensory attributes
of the soy
milk produced
Research Methods
Materials
The research was carried
out at the Analytical Chemistry Laboratory, Faculty of Pharmacy, Universitas
Muhammadiyah Surakarta. The tools used are laboratory glassware, SPME (Solid
Phase Microextraction Supelco, USA), SPME fiber
PDMS/DVB (Polydimethylsiloxane/Divinylbenzene) 65 µm, GC - MS (Gas
Chromatography-Mass Spectrometry Detector) Shimadzu - GC 2010 equipped with
Shimadzu - GC 2010S, RxiTM-1MS chromatography column (30 m x 0.25 mm, layer
thickness 0.25 μm), macro pipette 1000 to 5,000 µL,
stative, burette clamp, magnetic stirrer, pan, stove, basin, filter cloth,
blender and stirrer. The ingredients used are imported soybeans originating
from the USA (United State of America) with the brand (Soybeans, USA BOLA) and
local soybeans originating from the Grobogan area,
Central Java, Water for injection (pro analysis - IKA Pharmindo,
Indonesia), mobile phase helium gas.
Soy Milk Making Process
The
soybeans are washed, soaked for 8 hours with a soybean and water ratio of 1:2
(w/v), squeezed to separate the soybean skin and boiled for 5 minutes. Next,
crush the soybeans using a blender by adding water in a ratio of 1:5 (w/v). The
soybean sprout pulp is wrapped in a filter cloth, then squeezed and the
filtrate is collected. The filtrate is boiled until it boils for 5 minutes over
medium heat while stirring gently.
SPME Fiber Cleaning
SPME
fiber was injected into the Gas Chromatography injection port, left in the
injection port for 30 minutes. Such as desorption of samples, and the injector
temperature used is 280℃.
Optimization
of GC-MS
Optimization of gas
chromatography with an MS (Mass Spectrometry) detector requires adjustments to
several important parameters to achieve optimal results. This process requires
settings such as a programmed increase in column temperature and adjustment of
the injection split ratio. This parameter setting is carried out to increase
sensitivity, ensure more optimal separation, control the number of samples
entering the column, and detect with high accuracy the identification of
analyte components present in the sample. Optimization of GC-MS in this study
involved the following parameters in Table 1.
Table 1. Parameter Optimization of GC-MS
|
Parameter |
Optimization |
|
Inject port temp. |
280⁰C |
|
Ion Source temp. |
200⁰C |
|
Interface temp. |
250⁰C |
|
Gas flow rate |
3,0 mL/min |
|
Carrier gas |
Helium |
|
Initial Column
Pressure |
84.6 kPa |
|
Column temp |
70°C (5 min) to
270°C (15 min) with a regulated temperature increase 10°C/min |
|
Mode of injection |
Split 10 : 1 |
|
Total program time |
40 min |
The initial column
temperature of 70⁰C was held for 5 minutes; rise 10⁰C/minute to 270⁰C held for
15 minutes. Split ratio 10 : 1. Analysis was carried
out by looking at the chromatogram results, the relative concentration (% Area)
obtained and the mass spectra of the samples which had been compared with the
internal Willey Library.
Sample Extraction
Extraction of Soy
Milk drink samples was carried out
using the SPME technique. The material was taken (5 mL) and
recorded, then put into a 10 mL
measuring flask and added to
10 mL with Water For Injection then vortexed. 5 ml of the dissolved sample
was taken and then put
into a 20 mL flacon, closed tightly using silicone.
Insert the SPME needle into the flacon,
then heat it at the
SPME optimization temperature
and time. When heating the
flacon, the SPME fiber is removed from
the SPME into the flacon to
absorb the analyte. After heating, the analyte
is injected into the GC - MS Injection Port, the injection results from SPME are analyzed by looking at
the chromatogram results, the relative
concentration (% Area) obtained
and the mass
spectrum of the sample which
has been compared with the internal Willey Library.
Optimization
of SPME
The sample (5 mL) was added
with water for injection in a 10 mL measuring flask and vortexed. A 5 ml sample was taken
and placed in a 20 mL flacon. Closed
tightly with silicone. Insert the SPME needle into the
flacon, then heat it at
the SPME optimization temperature and time as in Table 2.
Table 2. Extraction Temperature and Time Optimization of SPME
|
Temperature
(⁰C) |
Time (min) |
|
40⁰C |
10 min |
|
20 min |
|
|
30 min |
|
|
50⁰C |
10 min |
|
20 min |
|
|
30 min |
|
|
60⁰C |
10 min |
|
20 min |
|
|
30 min |
After heating using the
SPME optimization temperature and time, the analyte is injected into the GC-MS
injection port, the SPME injection results are analyzed by looking at the
chromatogram results, the relative levels (% Area) obtained and the total volatile
compounds detected. The mobile phase used in this research is helium gas
Statistical Analysis
Statistical
significance of the difference between total volatiles and the difference
between the relative levels of certain volatile compounds from soy milk
samples, namely, imported soy milk and local soy milk. Each value represents
the average of triple SPME analysis, namely one orientation analysis and two
replication analyzes. Error bars indicate SD (standard
deviation)
Result and Discussion
Analysis of the taste
and odor profiles of food
and drinks is very useful
for their quality. Apart from that, taste
and odor profiles are also used to determine
the right way to manage
derivative products from these foods
and drinks. One way to find
out the taste
and odor profile of food
or drink is by analyzing
the volatile compounds contained. There is even
research that states that volatile
compounds can also be good
antimicrobials. This proves that the
identification of volatile compounds in vegetable products, both food and
beverages, is very important.
1.
Optimization of Solid Phase Microextraction
a. Effect of
Incubation Time
The effect
of extraction time is very
important for maximum absorption results. The aim of optimization by increasing the
incubation time from 10 minutes, 20 minutes to 30 minutes
is to find
out at what
minute SPME can maximally encourage greater adsorption of volatile compounds
into the fiber by increasing the
analyte partition balance between the SPME fiber and the sample. The definition of adsorption
is the ability
of standard volatiles/analytes to adhere to
SPME fibers under the conditions studied and measured
using an MS detector. In Figure 1,
you can see
the change in total volatiles produced at each time.
Figure 1. Effect of incubation time on total volatiles
The graph shows that
there was an increase in the total volatiles detected in the 20th minute, namely 16.33 volatile compounds. After the 20th minute, there was a decrease
in the total volatiles detected, namely at the 30th minute
there were 12 volatile compounds. The decrease in total volatiles at 30 minutes probably occurred due to
reverse diffusion, resulting in analytes that had been absorbed
into the SPME fiber diffusing back into the sample
because they had reached the maximum
equilibrium point. Therefore, an incubation
time of 20 minutes is suitable
for use in sample analysis (optimal volatile recovery).
b. Effect
of Incubation Temperature
In analysis
using the SPME method, apart from
setting the incubation time during sample preparation,
it is also
necessary to set the appropriate temperature so that later sample
analysis produces maximum results. Here we use 3 temperatures
for optimization in the SPME method, namely at 40; 50; and 60⁰C. The aim of optimizing by
adjusting the incubation temperature is to accelerate
the release of analytes from
the sample matrix and increase
the analyte diffusion coefficient so that the
analytes can reach the fiber quickly and an
equilibrium partition occurs between the analyte and
the fiber. A graph of the differences
in volatile compounds detected at each
temperature can be seen in Figure
2.
Figure 2. Effect of incubation temperature on total volatiles
From the results obtained, it is known that there was an increase in
total volatiles from the lowest temperature, namely 40⁰C, namely 11 volatile
compounds, increasing to a temperature of 50⁰C, namely 16 volatile compounds
and reaching a peak at a temperature of 60⁰C, namely 17.33 volatile compounds.
This shows that the higher the sample extraction temperature, the more analytes
are absorbed into the SPME fiber, so that this can increase the number of
volatile compounds identified. In this way, the incubation temperature of 60⁰C
is suitable for use in sample analysis (recovery of total volatiles).
2.
Analysis of Volatile Compounds of Soy Milk Samples
a.
Sample Extraction
In the
analysis of volatile compounds in imported and local
soy milk samples, the first
thing that must be done
is to extract
the sample. In this research, sample extraction was carried out
using the headspace technique, which is a technique
with the principle that the analyte must
not come into direct contact with the SPME fiber. The SPME
fiber used in this research is PDMS/DVB (Polydimethylsiloxane/Divinylbenzene)
65 µm fiber. These fibers
are more efficient in
sampling highly volatile organic compounds. The advantage of using
this coating is that the
shorter extraction time speeds up
the analysis process and also
ensures linear extraction of compounds over time
Sample extraction
is carried out using samples
of the same
type but from different origins. The first sample uses soy
milk originating from imported soybeans
from the USA (United State of America) with the brand (Soybeans,
USA BOLA) while the second sample uses
soy milk from soybeans originating
from the Grobogan area, Central Java. Each sample was extracted
with the time and temperature
obtained during optimization, namely at 60⁰C for 20 minutes. Apart from that, the
sample volume used must be properly
regulated so that it is
not touched by the SPME fiber during extraction. The volume used is 5 mL for
each sample analyzed.
The results
of qualitative analysis using GC-MS show that total volatile compounds have been identified
in imported and local soy milk.
In this study, compounds
were grouped that frequently appeared in the analysis of
samples of imported soy milk
and local soy milk, each
in three copies (orientation, replication 1 and replication 2), with relatively high levels. Relative
concentration is defined as the proportion of the
peak area of each component relative to the
total area of all peaks in the chromatogram.
It is often
used to determine
the relative composition of each component in a sample.
The
grouping of compounds from all samples can be seen from the cluster analysis
results in Table 3. Cluster data analysis is used to classify the GC-MS
analysis results based on the presence of compounds that frequently appear in
each analysis. Compounds that appear frequently and have relatively high levels
(>1%) are major compounds, while compounds with relatively small levels
(<1%) are minor compounds
Table 3. Volatile
compounds in local and imported soy
milk with 2 replications
|
No |
Name
Compound |
Relative
levels (% area) Import |
Relative
levels (% area) Local |
||||
|
Ori |
Rep 1 |
Rep 2 |
Ori |
Rep 1 |
Rep 2 |
||
|
1 |
Pentanal (Pentanal, n-pentanal valeraldehyde) |
2,42 |
7,02 |
1,93 |
2,47 |
9,57 |
2,05 |
|
2 |
Ester (O-(2-Methylethyl) ester of carbamothioic acid and 4-hexenoic acid,2,2,5-trimethyl, ethylester) |
1,84 |
3,64 |
4,10 |
- |
- |
8,75 |
|
3 |
Siloksan (Decamethylcyclopentasiloxane and octamethylcyclotetrasiloxane) |
2,09 |
8,10 |
1,58 |
1,26 |
- |
2,51 |
|
4 |
Benzaldehyde |
- |
6,73 |
|
- |
5,73 |
- |
|
5 |
Benzenemethanol, benzyl
alcohol |
- |
- |
61,74 |
- |
- |
11,70 |
|
6 |
Acetophenon semicarbazone |
1,97 |
- |
- |
- |
- |
- |
|
7 |
1,2-Benzenediol, 3,5bis(1,1-dimethylethyl) |
1,05 |
- |
- |
- |
- |
2,51 |
|
8 |
1-undecen-3-ol. 1-phenyl |
3,22 |
- |
- |
- |
- |
- |
|
9 |
Methoxy, phenyl, oxime |
1,54 |
- |
- |
- |
- |
- |
|
10 |
Cyclohexane, 1-(1,1-dimethylethyl) |
2,00 |
2,76 |
- |
2,60 |
- |
- |
|
11 |
Endo-isofenchol, bicyclo(2,2,1)heptane-2-ol |
- |
1,70 |
- |
- |
- |
- |
|
12 |
1,3-oxazetidin-2-one, 3-phenyl |
- |
- |
3,24 |
- |
- |
- |
|
13 |
Propane, 1,1-dicloro, 1,1-dichloropropane |
- |
- |
3,38 |
- |
- |
- |
|
14 |
3-butenoic acid, vinylacetic
acid |
- |
- |
1,51 |
- |
- |
- |
|
15 |
EZ-3-methyl-2,4-hexadiene, 2,4-hexadiena,3-methyl |
- |
- |
1,93 |
- |
- |
- |
|
16 |
Benzenemethanol,
alpha-(1-aminoethyl, norephedrine |
- |
- |
1,93 |
- |
- |
- |
|
17 |
2,2-diphenyl-1,3,2-benzo-dioxa-4H-tellune |
- |
- |
1,13 |
- |
- |
- |
|
18 |
Acetamide, 2-fluoro |
27,51 |
- |
- |
- |
- |
2,52 |
|
29 |
D-alanine |
- |
- |
7,06 |
- |
- |
- |
|
20 |
Cyclopentene, 3 heptyl |
- |
- |
- |
5,00 |
3,90 |
8,75 |
|
21 |
Cyclohexanol,2-(1-methylethyl) |
- |
- |
- |
- |
3,90 |
- |
|
22 |
1-Napthalenecarboxaldehyde |
- |
1,14 |
- |
- |
- |
- |
|
23 |
1-octen-3-ol |
1,29 |
- |
- |
- |
- |
- |
Note : (-)
Relative Levels (<1%) not counted
The major
compounds identified in the two soy
milk samples with high similarity
were pentanal, alcohol, siloxane, ester, benzaldehyde, while for cyclopentene,
it only appeared
in the local soy milk samples.
Many other compounds were detected but in relatively small levels (<1%) or below the
instrument threshold so they were not counted in the total volatile compounds. The results of statistical
analysis show that the type
of soybean between imported and local has a significant effect on the total number
of volatiles identified. (P < 0.05) Figure
3. This significant difference probably occurs due to
differences in the origin of the
soybeans used in making soy milk, including
age, origin, time and method
of harvesting, drying and soybean
production processes.
Figure 3. Total volatile
compounds detected in imported and local
soy milk
The major compounds identified in the two soy
milk samples greatly influenced the taste and
aroma characteristics of soy milk. The taste
resulting from major compounds such as carbonyl compounds such as pentanal in soy milk has a green, woody pleasant odor, nutty aroma, and gives a slightly
sweet taste like honey. Meanwhile,
the carbonyl compound benzaldehyde reportedly does not really contribute to the taste
of soy milk,
however, benzaldehyde has a
masking effect because its aroma resembles cherry or almond. The alcohol compounds contained here such as 1-octen-3-ol describe an earthy, mushroom-like,
and slightly vegetable aroma and have a taste like
green, oily, and faintly fatty
(creamy feel). Siloxane compounds generally have no taste, but
these compounds usually have benefits
such as natural preservatives
in food to slow the spoilage
process and maintain the texture
and taste of the product.
The ester compound here is defined as having
a honey-like aroma and a floral taste. The distribution of GC-MS chromatogram peaks for the major
compounds can be seen in Figure
4 &
5.
A
Figure 4.(A) Chromatogram of volatile compounds in imported soy
milk
B
Figure 5 (B) Chromatogram of
volatile compounds in local soy milk
The
differences in volatile compound components in soy milk are not only based on
the total volatiles produced. This data is not enough to show the taste and
odor profile of soy milk. Therefore, more specific research is needed, by
comparing the relative levels of major compounds (>1%) and compounds that
frequently appear in both samples with the resulting triplicate analysis. The
compound that appeared in the six analyzes was. The imported samples of
pentanal compounds in orientation, replication 1, and replication 2 each had a
relative level of 2.42%; 7.02%; 1.93%, while local samples of pentanal
compounds in orientation, replication 1, and replication 2 each had relative
levels of 2.47%; 9.57%; 2.05%, the relative content graph can be seen in Figure
6.
Figure 6. Comparison of
relative levels of major compounds
from imported and local soy
milk
The relative levels of each
sample obtained were subjected to statistical
analysis. The results showed that the
pentanal compound in imported and local
soy milk had no significant effect on the
relative levels produced (P > 0.05). This shows that the
taste and odor characteristics produced by the
pentanal compound do not significantly influence the differences
in the origin of the samples
used.
Conclusion
The Solid Phase
Microextraction - Gas Chromatography (SPME - GC) method is an appropriate
method to use to identify the volatile compound content in soy milk products.
This research shows that good optimization for analyzing imported and local soy
milk samples is at a temperature of 60⁰C for 20 minutes. The maximum volume
used is 5 mL to prevent direct attachment of the sample to the SPME fiber. The
difference in total volatiles produced between the two soy milk samples shows
that there is a significant difference (P < 0.05), so it can be concluded
that the origin of imported and local soybeans used to make soy milk influences
the total number of volatile compounds identified. Furthermore, the differences
in relative levels between the pentanal compounds in the two soy milk samples
showed insignificant results (P > 0.05), so it can be concluded that the
taste and aroma characteristics produced by the pentanal compounds did not
significantly influence the differences in the origin of the samples used.
BIBLIOGRAPHY
Achouri, A., Boye, J. I., & Zamani, Y. (2006). Identification of
volatile compounds in soymilk using solid-phase microextraction-gas
chromatography. Food Chemistry, 99, 759–766.
https://doi.org/10.1016/j.foodchem.2005.09.001
Adawiyah, D. R., Andarwulan, N., Triana, R. N., Agustin, D., & Gitapratiwi, D. (2018). Evaluas Perbedaan Varietas Kacang Kedelai terhadap Mutu Produk Susu Kedelai. Jurnal Mutu Pangan, 5(1), 10–16.
Al-Rubaye, A. F., Hameed, I. H., & Kadhim, M. J. (2017). A Review: Uses of Gas Chromatography-Mass Spectrometry (GC-MS) Technique for Analysis of Bioactive Natural Compounds of Some Plants. International Journal of Toxicological and Pharmacological Research, 9(1), 81–85. https://doi.org/10.25258/ijtpr.v9i01.9042
Badulla, Wafa. F., Al-Maqdi, D. H., & Bamahmood, Ebtesam. S. (2021). In Vitro Biopharmaceutical and Physicochemical Evaluation of Different Brands of Ciprofloxacin Marketed in Aden-Yemen. Malaysian Journal of Pharmaceutical Sciences, 19(2), 73–86. https://doi.org/10.21315/mjps2021.19.2.5
Balasubramanian, S., & Panigrahi, S. (2011). Solid-Phase Microextraction (SPME) Techniques for Quality Characterization of Food Products: A Review. Food and Bioprocess Technology, 4(1), 1–26. https://doi.org/10.1007/s11947-009-0299-3
Fadida, T., Selilat-Weiss, A., & Poverenov, E. (2015). N-hexylimine-chitosan, a biodegradable and covalently stabilized source of volatile, antimicrobial hexanal. Next generation controlled-release system. Food Hydrocolloids, 48, 213–219. https://doi.org/10.1016/j.foodhyd.2015.02.033
Fuchsmann, P., Stern, M. T., Münger, L. H., Pimentel, G., Burton, K. J., Vionnet, N., & Vergéres, G. (2020). Nutrivolatilomics of urinary and plasma samples to identify candidate biomarkers after cheese, milk, and soy-based drink intake in healthy humans. Journal of Proteome Research, 19, 4019–4033. https://doi.org/10.1021/acs.jproteome.0c00324
Hanwar, D., Arsanti, T. N., Primaharinastiti, R., & Yuwono, M. (2023). Analysis of Residual Solvents in Co-amoxiclav Coated Tablets Using Solid Phase Microextraction–Gas Chromatography. In Proceedings of the 4th International Conference Current Breakthrough in Pharmacy (ICB-Pharma 2022). Atlantis Press International BV. https://doi.org/10.2991/978-94-6463-050-3_20
Hidayatullah, M. H., Ibrahim, S., & Permana, B. (2022). Pengembangan Dan Validasi Metode Analisis Amlodipin Besilat dan Identifikasi Cemarannya Dalam Sediaan Tablet. Pharmacon: Jurnal Farmasi Indonesia, 19(2), 148–159. https://doi.org/10.23917/pharmacon.v19i2.20210
Mawarni, R. D., Anggraini, Y., & Jumari, A. (2018). Pembuatan Susu Kedelai Yang Tahan Lama Tanpa Bahan Pengawet. Seminar Nasional Teknik Kimia Ecosmart 2018, 122–128.
Mendoza-Avendaño, C., Ovando-Chacón, S. L., Luján-Hidalgo, M. C., Meza-Gordillo, R., Ruiz-Cabrera, M. A., Grajales-Lagunes, A., Gutiérrez-Miceli, F. A., & Abud-Archila, M. (2022). Volatile Compounds in Tofu Obtained by Soy Milk Fermentation with Lactobacillus plantarum BAL-03-ITTG and Lactobacillus fermentum BAL-21-ITTG. Current Microbiology, 79(317), 1–11. https://doi.org/10.1007/s00284-022-03014-0
Novi, C., Apriliane, K. L., & Oktavia, S. (2024). Chemical Profiling of Essential Oil Extracted from Fresh Walang Leaves (Etlingera walang (Blume) R. M. Sm.), an Indigenous Species in Banten, Indonesia. Bioeksperimen: Jurnal Penelitian Biologi, 10(1), 23–29.
Pointke, M., Albrecht, E. H., Geburt, K., Gerken, M., Traulsen, I., & Pawelzik, E. (2022). A Comparative Analysis of Plant-Based Milk Alternatives Part 1: Composition, Sensory, and Nutritional Value. Sustainability, 14(7996), 1–23.
Salih, B., & Celikbicak, O. (2012). Gas Chromatography in Plant Science, Wine Technology, Toxicology and some specific Application (B. Salih & O. Celikbicak, Eds.). InTech.
Suhendi, A., Rohman, A., Wahyono, D., Nurrochmad, A., & Manggo, T. F. (2023). Validasi Metode Analisis LC-MS/MS Pada Penetapan Kadar Isoniazid Dalam Serum Tikus Validation of Analytical Method LC MS/MS for Determination Isoniazid in Rats Serum. Pharmacon: Jurnal Farmasi Indonesia, 20(2), 96–103.
Yulifianti, R., Ginting, E., & Utomo, J. S. (2020). Karakteristik Fisiko-Kimia dan Sensoris Susu Kecambah Beberapa Varietas Unggul Kedelai. Buletin Palawija, 18(2), 83–93. https://doi.org/10.21082/bulpa.v18n2.2020.p83-93
Zhang, R., Tang, C., Jiang, B., Mo, X., & Wang, Z. (2021). Optimization of HS-SPME for GC-MS Analysis and Its Application in Characterization of Volatile Compounds in Sweet Potato. Molecules, 1–18.
|
Copyright holder: Aisah
Kensar Nawang Wulan Sari, Dedi Hanwar (2024) |
|
First publication right: Syntax Literate:
Jurnal Ilmiah Indonesia |
|
This article is licensed under:
|
