What Is Preservatives?
Preservative analysis is the determination of the amount of additives added to food to extend its shelf life. Benzoic and sorbic acid are measured by HPLC, sulfite by distillation-titration or enzymatic method, and nitrite and nitrate by ion chromatography or spectrophotometric method.
Purpose of Preservatives
The aim is to determine whether the preservative used is allowed in the product group and whether the amount exceeds the maximum level in the legislation. In addition, the accuracy of the 'preservative-free' statement is checked with this analysis.
Which Products Is Preservatives Applied To?
- Soft drinks and juices
- Pickles, tomato paste and sauces
- Delicatessen and meat products (nitrite/nitrate)
- Dried fruit and starch products (sulphite)
- Unlu mamuller
In Which Sectors Is Preservatives Used?
Standards Related to Preservatives
- EN 12856 (benzoic and sorbic acid — HPLC)
- EN 1988-1 / -2 (determination of sulphide)
- EN 12014 series (nitrate and nitrite)
- Turkish Food Codex Food Additives Regulation
Preservatives Conditions
- Method
- HPLC-UV (benzoat/sorbat), iyon kromatografisi veya spektrofotometri (nitrit/nitrat)
- Sulphite
- Distillation-titration (Monier-Williams) or enzymatic method
- Sample preparation
- Extraction, deproteinization and filtration
- Calibration
- Separate standard for each protector
Equipment for Preservatives
- Analytical balance and homogenizer
- Sample preparation apparatus (extraction, filtration, concentration)
- Kromatografi veya spektrometri sistemi
- Temperature controlled storage and conditioning cabinets
Sample Requirements for Preservatives
- The sample should be taken to be homogeneous and representative of the lot.
- For analytes that are sensitive to light or oxygen, a dark colored and tightly closed container should be used.
- The sample amount varies with the number of analytes; If more than one analysis is requested, the total amount increases.
- The product name, list of ingredients and declared value, if any, must be provided with the sample.
Duration of Preservatives
Determinations made by HPLC can be completed within one business day. Monier-Williams distillation takes longer per sample.
Preservatives Procedure
- 1The sample is homogenised and weighed.
- 2Extraction appropriate to the preservative is applied.
- 3The extract is cleaned and filtered.
- 4HPLC veya ilgili sisteme verilir.
- 5Quantity is calculated via the calibration curve.
- 6The result is reported in mg/kg.
Preservatives Acceptance Criteria
The legislation, not the method, determines whether the result will be considered appropriate or not. The relevant communiqué of the Turkish Food Codex, EU 2073/2005 and 1881/2006 and the specification of the buyer company define different limits depending on the product group; The report gives the measured value and takes the limit from the applicable legislation.
Evaluation of Results
The result is compared with the maximum level of the Turkish Food Codex Food Additives Regulation in the relevant product category. The same item has different limits in different product groups; The evaluation is made after the product category is determined correctly.
Preservatives Report
- Sample description, batch/lot information and arrival conditions
- Sampling method (if taken by the laboratory)
- Applied analysis method and reference standard
- Analysis date and incubation conditions, if any
- Result and its unit
- Measurement uncertainty (if requested)
- A statement that the result applies only to the specimen submitted for testing
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- Turkish Food Codex Regulation and related product communiqués
- EU 1881/2006 — maximum limits of contaminants in food
- Turkish Food Codex Labeling and Consumer Information Regulation
Food Testing — What Does This Testing Field Cover?
The section below describes the field that the Preservatives test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
Food testing shows that a product is safe for consumption and contains what its label states. The family works along three axes: microbiological safety, chemical safety and nutritional composition. All three require different laboratory infrastructure, a different body of methods and a different turnaround time.
The most distinctive feature of the field is TIME PRESSURE. A steel specimen can wait on a shelf; a raw milk or fresh meat sample cannot. The time the sample was taken, the transport temperature and how long it takes to reach the laboratory directly determine the validity of the result. In food microbiology the cold chain record is therefore an inseparable part of the test report.
On the microbiological side there are two different questions and they must not be confused. DETECTION of a pathogen is a qualitative question: is Salmonella present in the sample or not? ENUMERATION of indicator organisms is a quantitative question and an indicator of production hygiene. The absence of a pathogen in a product does not show that hygiene is good; if the total mesophilic aerobic count is high, there is a problem in the process.
On the chemical side, pesticide residues, mycotoxins, heavy metals, additives, veterinary drug residues and process contaminants (acrylamide, furan, PAH) are measured. Multi-residue methods in this area (QuEChERS-based LC-MS/MS and GC-MS/MS) can screen hundreds of active substances in a single analysis; limits are defined separately for each product–substance pair.
On the composition side, protein, fat, moisture, ash, fibre, sugar profile, fatty acid composition, vitamin and mineral content are determined. These values are the basis of the nutrition declaration on the label and the tolerance ranges are defined in legislation — the difference between the declared value and the measured value must stay within that tolerance.
There is NO CE marking on food, and this shapes how the field works. Conformity is demonstrated through operating a HACCP-based food safety system, complying with labelling rules and not exceeding contaminant, residue and microbiological limits. A test result produces evidence not for a certificate but for a functioning system.
Allergen management carries particular weight. The presence of an undeclared allergen in a product is one of the most frequent causes of food recalls. Analysis here runs together with cleaning validation: it is shown that the line has been cleaned adequately after a production run containing an allergen and that the risk of cross-contamination is under control.
Voluntary schemes have become effectively mandatory in this field. Retail chains require their suppliers to hold a certificate under a GFSI-recognised scheme (BRCGS, IFS, FSSC 22000); without it, getting onto the shelf is practically impossible.
Method groups in this field
Pathogen detection
Detection of Salmonella, Listeria monocytogenes, Campylobacter, Cronobacter and Shiga toxin-producing E. coli; culture-based and molecular methods.
Indicator counts
Total mesophilic aerobic count, Enterobacteriaceae, coliforms and E. coli, coagulase-positive staphylococci, yeasts and moulds, lactic acid bacteria, sulphite-reducing Clostridia.
Pesticide and veterinary residues
Multi-residue screening by LC-MS/MS and GC-MS/MS with QuEChERS extraction.
Mycotoxins and contaminants
Aflatoxins, ochratoxin A, deoxynivalenol, patulin; heavy metals (ICP-MS), acrylamide and PAH compounds.
Nutritional composition
Kjeldahl protein, fat and fatty acid profile, moisture, ash, dietary fibre, sugar profile, vitamin and mineral analyses.
Allergens and authenticity
Gluten, milk, egg, nut and soy allergen analyses; molecular methods for species identification and adulteration detection.
Commonly confused in this field
- Sampling is half the result. A sample transported at the wrong temperature or delayed gives an invalid result even if it is analysed correctly in the laboratory.
- The absence of a pathogen does not show that hygiene is good; indicator counts give separate information and the two are read together.
- A result from a sample taken from a lot can be generalised to the whole lot only if the sampling plan was set up statistically.
- Limits are defined in separate regulations by product group and are updated regularly; a conformity decision based on an outdated limit table may be wrong.
- For exports, the limits of the destination country may differ from EU limits; the same product may be compliant in one market and non-compliant in another.
Which decisions these results support
- Verification of the HACCP plan and process monitoring
- The basis for the nutrition declaration and allergen information on the label
- Health certificates before export and compliance with destination market limits
- Supplier and lot-based acceptance control
- Shelf-life studies and determining storage conditions
- Producing evidence for audits under GFSI-recognised schemes
Related Tests
Frequently Asked Questions About Preservatives
Is naturally occurring benzoic acid a problem?
Benzoic acid can be found naturally in some products (for example, dairy products and some fruits). This natural contribution is taken into account in the evaluation; The legislation addresses this separately.
Why is sulfite measured by a separate method?
Sulfite is found in food in free and bound forms and is volatile. Therefore, distillation-based or enzymatic methods are used instead of chromatographic measurement.