Sample and Laboratory Analysis in Carob Trade
The most concrete basis of trust between the buyer and the seller in the trade of carob and carob products is the representative sample and the laboratory analyzes performed on this sample. Moisture, sugar, ash, protein, mineral, HMF and adulteration tests; It becomes part of the specification according to the type of product and its intended use.
In this article, we discuss how samples should be taken in the carob trade, which analyzes stand out for which product, analysis methods used in scientific studies, and points to consider when choosing an accredited laboratory.
Why Are Samples and Analysis So Important?
Carob is a natural agricultural product and its composition varies depending on the variety, the region where it is grown, the time of harvest and the processing conditions. For example, in three carob varieties grown in Cyprus, the moisture in the fruit flesh was found to be between 13.59–14.80 percent and the sugar was found to be between 53.59–54.83 percent (Papaefstathiou et al., 2018). In a study examining wild carob in Morocco, it was observed that the total sugar, protein, and mineral values differed significantly according to the collection region (Laaraj et al., 2024).
This inherent variability means that saying "carob" alone is not enough in trade. The buyer wants to know if the product he is buying is suitable for his production process; the seller wants to certify that his product meets the specified criteria. This common language between the two parties is established through representative samples and reliable laboratory analysis.
How to Get a Representative Sample?
The value of the analysis depends on how well the sample represents the batch. Even the most sensitive laboratory cannot produce an accurate result from an incorrectly taken sample.
- The sample should not be created from a single point in the batch, but by combining sub-samples taken from different sacks, big bags or layers.
- The combined sample should be homogenized by mixing and divided if necessary.
- Sample; It should be placed in clean, dry and sealable packages, and moisture should be prevented.
- Each sample; It should be labeled with the product name, batch number, date, place of receipt and recipient information.
- A sealed witness sample should be separated and stored under appropriate conditions in case of possible disputes.
- The preliminary sample and the shipment batch must be the same product, traceable with batch number and documents.
One of the common problems in trade is that the preliminary sample turns out to be different from the shipping batch. For this reason, the contract should determine from the beginning how the sample will be collected, in which laboratory it will be analyzed and with what tolerances the results will be evaluated.
Featured Analyzes by Product
Which analyses are required depends on the type of product and the buyer's intended use. The table below provides a general framework; the exact list is always determined by the buyer's specification.
| Product | Frequently requested physical/chemical analyses | Additional requests |
|---|---|---|
| Carob fruit and kibble | Moisture, foreign matter, grain/piece size, sugar | Mycotoxin, insect/pest control, nucleus ratio |
| Carob flour / powder | Moisture, ash, particle size, color, sugar | Protein, fiber, mineral, microbiology, mycotoxin |
| Carob molasses / syrup | Soluble dry matter (Brix), HMF, pH, sugar profile | Adulteration (glucose syrup) test, mineral, microbiology |
| Carob seeds | Moisture, purity, broken/damaged core ratio | Gum (galactomannan) yield, protein |
| Carob extract | Brix, sugar, HMF, phenolic substance | Determination of specific component (e.g. D-pinitol) |
There is also an internationally prepared product standard for carob: ISO 7907:1987 "Carob — Specification" standard covers quality elements such as odor, taste, freedom from live insects and pests, damaged fruit, foreign matter and moisture for ripe and dried carob fruit; sampling, test methods, packaging and marking. According to ISO's records, this standard was repealed in 2019; however, its scope continues to be a guide in terms of showing which parameters are looked at in the dried fruit trade.
Some of these analyzes (humidity, Brix, pH) are quick and relatively simple measurements; some of them (mineral profile, sugar profile, adulteration tests) require special equipment and expertise.
Basic Chemical Analysis and Methods
In scientific studies, the composition of carob and its products is determined by internationally accepted methods. The study by Papaefstathiou et al. (2018), in which carob and traditional carob products were examined, is a good example of these methods:
| Humidity | Thermogravimetric method (drying in an oven); ISO and AOAC methods were referred to in the study. |
| Ash | It is determined by burning the sample at high temperature (550 °C). |
| Protein | It is calculated based on the determination of nitrogen by the Kjeldahl method. |
| Sugars | With HPLC, sucrose, glucose, and fructose are measured separately using a refractive index detector. |
| Minerals | After microwave dissolution, elements such as potassium, calcium, magnesium, iron and zinc are determined with the ICP-OES device. |
In the same study, it was stated that certified reference materials were used for the reliability of the measurements. This detail is also important from a commercial point of view: A reliable laboratory regularly checks the accuracy of its results with reference materials and proficiency tests.
In liquid products such as molasses and syrup, soluble dry matter is measured in Brix with a refractometer (Yaman and Duraklı Velioğlu, 2019). Dilek et al. (2025), who examined traditional molasses in Turkey, also compared different types of molasses by analyzing total soluble dry matter, HMF, sugar profile, vitamins, and essential amino acids.
HMF Analysis in Molasses and Syrups
HMF (hydroxymethylfurfural) is a compound that can form during heat treatment and storage in sugary products; it is an important quality indicator that provides information about the intensity of heat treatment and freshness in molasses. For this reason, HMF analysis is among the frequently requested parameters in molasses and syrup trade.
Scientific studies show that HMF values can vary in a wide range. Yavuz Küçük and Duraklı Velioğlu (2022) measured HMF in the range of 0.79–50.25 mg/kg in carob molasses collected from the market and 1.25–68.77 mg/kg in products sold under the name "carob extract". In the study of Dilek et al. (2025), HMF values ranged from 2.28 mg/kg to 1238.43 mg/kg among different types of molasses; 3.89 mg/kg was found in carob molasses. In the same study, it is stated that the HMF limit in the legislation for grape molasses is 75 mg/kg.
In a study conducted on mulberry molasses, the type classification of the product in the TSE 12001 standard was made based on the HMF value (Petek, 2026). This example shows that HMF is not only a quality indicator but also a parameter used in the classification of the product according to the standard.
Another analysis subject specific to carob molasses is benzoic acid. According to the announcement of the Ministry of Agriculture and Forestry, General Directorate of Food and Control dated March 14, 2025, benzoic acid can be found naturally in carob molasses; therefore, a decision limit of 250 mg/kg will be used to evaluate benzoic acid from the nature of the product, and if this value is exceeded, it will be evaluated that benzoic acid does not come from the natural structure of carob. This regulation is a good example that the natural composition of the product should also be taken into account when interpreting the analysis results.
For details of quality criteria in carob molasses What is Carob Molasses and How is it Made? You can also take a look at our article.
Adulteration and Authenticity Tests
One of the most significant risks in high-value sugary products such as molasses and syrups is adulteration with cheaper sugars. Turkish food legislation prohibits adding glucose syrup, high fructose corn syrup, or other sugars to molasses (Yaman and Duraklı Velioğlu, 2019). Therefore, buyers may request authenticity tests, especially for large-volume purchases.
FTIR spectroscopy: Yaman and Duraklı Velioğlu (2019) developed an approach that detects glucose syrup additive in grape, carob, and mulberry molasses by ATR-FTIR spectroscopy and chemometric models. The models distinguished between pure and adulterated samples with high accuracy and were able to predict the adulteration rate. This method is promising for screening use due to its speed.
Carbon isotope ratio analysis: The difference in the photosynthesis pathways of plants gives products different carbon isotope signatures. Jamali et al. (2024) showed that when glucose, fructose, and sugar beet syrup were added to grape molasses, the δ13C value changed significantly, and adulteration could be investigated quickly and accurately with this method. In the same study, physicochemical parameters such as Brix, conductivity, specific gravity, pH, moisture, ash, and HMF were also examined.
Originality tests require more specialized devices and databases than standard quality analyses. For this reason, it should be asked in advance which laboratory performs these tests and with which method.
Food Safety Analysis
In addition to chemical composition, analyzes for food safety are also an important part of trade. For carob products, the following analyzes may be requested according to the buyer's specification and the legislation of the target market:
- Microbiological analyses (in products consumed directly such as powders and syrups)
- Mycotoxin analyses (especially for risks related to storage conditions)
- Pesticide residue analysis
- Heavy metal analysis
Since the legal limits in these analyzes differ according to the product group and the target country, the current legislation of the market to be exported should be checked separately each time. Aliyazıcıoğlu et al. (2009), who examined different types of molasses from Turkey, reported that the samples they examined did not pose a risk to public health; however, such general findings do not replace the analyzes that should be done for each batch.
How to Choose an Accredited Laboratory?
The most accepted analysis reports in commercial disputes and official processes are those obtained from accredited laboratories. Accreditation means that a laboratory's competence to perform a certain analysis with a specific method is evaluated and approved by an independent organization. The basic international standard for testing and calibration laboratories is ISO/IEC 17025; In Turkey, the national accreditation body in this field is the Turkish Accreditation Agency (TÜRKAK).
Here are some considerations when selecting a laboratory:
- It should be checked whether the laboratory is accredited for the desired analysis parameter and method, not in general (scope of accreditation).
- The method used, measurement uncertainty and detection limit should be specified in the analysis report.
- Whether there is a recognized accreditation in the buyer's country should be confirmed before export.
- The analysis time and sample amount should be learned in advance and shipment planning should be made accordingly.
- The vendor's internal quality control results and independent laboratory results should be evaluated together.
What Should a Certificate of Analysis (CoA) Include?
In wholesale and export transactions, the Certificate of Analysis (CoA) prepared by the seller for each batch is the basic document showing the product's compliance with the specification. A well-prepared CoA usually contains the following information:
- Product name, batch/lot number, production and expiration dates
- Specification value and measured result for each parameter
- Analysis method used
- Name of the laboratory performing the analysis and approval information
An example of how important label and analysis compliance is is the study of Papaefstathiou et al. (2018): Only 60 percent of the 20 conventional carob products examined had a nutritional label label, and 75 percent of the products with a label found the measured values to be compatible with the label. Similarly in trade, the overlap of declared values and independent analysis results is the basis of trust.
Frequently Asked Questions
Which is the most basic analysis in carob purchase? Moisture and impurities in dry products, Brix and HMF in molasses and syrups are among the most frequently requested basic parameters. The exact list is determined by the buyer's specification.
Is the seller's own analysis report sufficient? Most commercial relationships are based on the seller's CoA; however, when working with new suppliers or in case of disputes, an analysis by an independent and accredited laboratory is preferred.
How to prove that molasses is original? Methods such as FTIR spectroscopy and carbon isotope ratio analysis are used to detect added sugars such as glucose syrup.
How long should the witness sample be stored? This period is usually determined in the contract between the parties; the shelf life of the product and possible complaint periods should be taken into account.
Carob Supply with Carob Türkiye
Clarifying the sample, specification and analysis processes in wholesale and export transactions from the beginning is the basis of a healthy commercial relationship for both parties. As Carob Türkiye, we supply carob fruit, crumbs, flour/powder, seeds and extracts. Our products Our Products page; For your sample, specification, wholesale and export requests Contact Now You can contact us on our page.
Domestic resources
Yavuz Küçük, A., Duraklı Velioğlu, S., "Determination of Some Chemical Properties of the Product Offered for Sale Under the Name of 'Carob Extract' and Comparison with Carob Molasses", Gıda, 47(5), 889–903, 2022. doi.
org/ 10. 15237/ food. GD22033 Petek, B., "Nutritional profile of traditional Tortum Bağbaşı (Haho) mulberry molasses (molasses)", Toros University Journal of Food, Nutrition and Gastronomy, 4(2), 237–249, 2026. doi.
org/ 10. 58625/ jfng- 3076 Republic of Turkey Ministry of Agriculture and Forestry, General Directorate of Food and Control, "Decision Limit Determined for Benzoic Acid in Carob Molasses" (announcement), 14.03.2025. agriculture.
gov. en/ GKGM/ Announcement/ 634/ Carob- In molasses- … Aliyazıcıoğlu, R., Kolaylı, S., Kara, M., Yıldız, O., Sarıkaya, A. O., Cengiz, S., Er, F., "Determination of Chemical, Physical and Biological Characteristics of Some Pekmez (Molasses) From Turkey", Asian Journal of Chemistry, 21(3), 2215–2223, 2009. I'm hungry.
Selcuk. edu. en/ items/ 1003AAD7- 3ca8- 46fc- 8990- 4f... Foreign sources
Papaefstathiou, E., Agapiou, A., Giannopoulos, S., Kokkinofta, R., "Nutritional characterization of carobs and traditional carob products", Food Science & Nutrition, 6(8), 2151–2161, 2018. doi.
org/ 10. 1002/ FSN3. 776 Dilek, N. M., Babaoğlu, A. S., Ünal, K., Turan, M., Pırlak, L., Karakaya, M., "Nutritional Profile and Functional Characteristics of Various Types of Traditionally Produced PEKMEZ—Part I", Food Science & Nutrition, 13(7), e70662, 2025. doi.
org/ 10. 1002/ FSN3. 70662 Yaman, N., Duraklı Velioğlu, S., "Use of Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) Spectroscopy in Combination with Multivariate Methods for the Rapid Determination of the Adulteration of Grape, Carob and Mulberry Molasses", Foods, 8(7), 231, 2019. doi.
org/ 10. 3390/ foods8070231 Jamali, V., Emamifar, A., Beiginejad, H., Moradi, M., Rasouli, M., "Detection of adulteration in Iranian grape molasses added glucose/fructose/sugar beet syrups with 13C/12C isotope ratio analysis method", Food Science & Nutrition, 12(10), 8432–8440, 2024. doi.
org/ 10. 1002/ FSN3. 4259 Laaraj, S., Tikent, A., El-Rhouttais, C., Farihi, A., Ed-Dra, A., Bouhrim, M., Mothana, R. A., Noman, O. M., Salmaoui, S., Addi, M., Serghini-Caid, H., Noutfia, Y., Elfazazi, K., "Nutritional value, HPLC-DAD analysis and biological activities of Ceratonia siliqua L. pulp based on in vitro and in silico studies", Scientific Reports, 14, 31115, 2024. doi.
org/ 10. 1038/ S41598- 024- 82318- 6 International Organization for Standardization, "ISO 7907:1987 Carob — Specification" (repealed in 2019), 1987. ISO.
Scientific Resourcesorg/ standard/ 14869. html
