Determination of benzoic and sorbic acids in Brazilian food

Development of a monoclonal antibody-based lateral flow immunoassay for the detection of benzoic acid in liquid food

To monitor benzoic acid (BA) residues in liquid food samples, a monoclonal antibody (mAb)-based lateral flow immunoassay (LFA) was developed in this study. First, 2-aminobenzoic acid (2-AA), 3-aminobenzoic acid (3-AA), and 4-aminobenzoic acid (4-AA) were conjugated to BSA and used as immunogens. After cell fusion, mAb 6D8 from 4-AA-BSA performed best with an IC50 value of 0.21 mg L-1 using 3-AA-OVA as a heterogeneous antigen, which represented a 3.4-fold improvement compared with the homogeneous antigen 4-AA-BSA. Subsequently, eight kinds of CGNPs with sizes varying from 20.94 nm to 90.00 nm were synthesized for screening the suitable size to develop a sensitive LFA. Finally, a sensitive LFA based on colloidal gold (23.27 nm) nanoparticles was developed for screening BA with a cut-off value of 4 mg L-1, which could meet the requirement of BA detection in milk, Fanta, Sprite, Coca-Cola, and Smart samples.

Polyphenols: Natural Preservatives with Promising Applications in Food, Cosmetics and Pharma Industries; Problems and Toxicity Associated with Synthetic Preservatives; Impact of Misleading Advertisements; Recent Trends in Preservation and Legislation

The global market of food, cosmetics, and pharmaceutical products requires continuous tracking of harmful ingredients and microbial contamination for the sake of the safety of both products and consumers as these products greatly dominate the consumer's health, directly or indirectly. The existence, survival, and growth of microorganisms in the product may lead to physicochemical degradation or spoilage and may infect the consumer at another end. It has become a challenge for industries to produce a product that is safe, self-stable, and has high nutritional value, as many factors such as physical, chemical, enzymatic, or microbial activities are responsible for causing spoilage to the product within the due course of time. Thus, preservatives are added to retain the virtue of the product to ensure its safety for the consumer. Nowadays, the use of synthetic/artificial preservatives has become common and has not been widely accepted by consumers as they are aware of the fact that exposure to preservatives can lead to adverse effects on health, which is a major area of concern for researchers. Naturally occurring phenolic compounds appear to be extensively used as bio-preservatives to prolong the shelf life of the finished product. Based on the convincing shreds of evidence reported in the literature, it is suggested that phenolic compounds and their derivatives have massive potential to be investigated for the development of new moieties and are proven to be promising drug molecules. The objective of this article is to provide an overview of the significant role of phenolic compounds and their derivatives in the preservation of perishable products from microbial attack due to their exclusive antioxidant and free radical scavenging properties and the problems associated with the use of synthetic preservatives in pharmaceutical products. This article also analyzes the recent trends in preservation along with technical norms that regulate the food, cosmetic, and pharmaceutical products in the developing countries.

Fast Sensitive and Accurate Analysis of the Most Common Synthetic Food Colorants in 65 Egyptian Commercial Products Using New HPLC–DAD and UPLC-ESI–MS/MS Methods

Overexposure to food colorants above the allowed daily intake (ADI) level can provoke hyperactivity and other disturbed behaviors especially in children. Two new methods were developed to separate five synthetic colorants, which were Tartrazine (E102), Sunset Yellow (E110), Allura Red (E129), Carmoisine (E122), and Brilliant Blue (E133). They are labeled on a large variety of commercial food products in the Egyptian market without mentioning their definite concentrations. Therefore, there was a real need to determine these colorants with simple, accurate, and fast methods. This is the first study to determine these colorants in a wide variety of food products present in the Egyptian market. The HPLC approach with photodiode array detection was developed to quantify these colorants, on a C18 column, with a mobile phase composed of acetonitrile and water containing 1% ammonium acetate (pH 6.8), separation was carried out using a gradient program. The colorants were eluted and efficiently separated within 9 min. Then, as a complementary technique to HPLC, the UPLC-ESI–MS/MS approach was developed for identification and accurate mass measurement of the colorants found in high concentrations, the colorants were obtained simultaneously in negative mode, the run time was only 3 min. These developed methods were validated according to ICH recommendations and they were applied to analyze 65 food products including jelly powder, puddings, ice cream powders, concentrated soft drink powders, carbonated drinks, chewing gums, and sugar confectionery.

Exposure assessment of benzoic acid from processed foods in South Korea

To evaluate the dietary exposure to benzoic acid of Korean consumers, the daily intake of benzoic acid was estimated using benzoic acid concentrations from processed food survey data in South Korea and food consumption data from the Korean National Health and Nutrition Examination Survey in 2018. The results were compared with the acceptable daily intake (ADI) stipulated by the Joint FAO/WHO Expert Committee on Food Additives. In addition, we estimated the effects and risk of benzoic acid intake, which may be increased by including amounts of naturally occurring benzoic acid recently established by the Ministry of Food and Drug Safety. Benzoic acid analyses were conducted in South Korea in 2020 for a total of 127,628 samples; it was detected in 1,803 samples, a detection rate of 1.4%. The mean contents of total samples and detected samples were 1.3 mg/kg and 89.4 mg/kg, respectively. The estimated daily intake (EDI) of benzoic acid for average consumers using a mean value of detected samples was 207.3 μg/kg.bw/day, which is 4.1% of ADI. The EDI of benzoic acid for high consumers (95^th percentile) of processed foods among the consumers was 1,406.7 μg/kg.bw/day, which is 28.1% of the ADI. As a result of estimating the intake of benzoic acid, which may be increased by a newly established standard on natural occurrence in South Korea, the theoretical maximum EDI of benzoic acid was 109.9 μg/kg.bw/day, which is 2.2% of the ADI.

WinMLR program for the determination of sorbic and benzoic acids in food samples

The program WinMLR has been developed to quantify sorbic and benzoic acids in soft drinks, fruit juices, and soy sauce by making a multilinear regression treatment of experimental data to a linear combination of standard signals. The spectra of sorbic and benzoic acid and samples were obtained from a conventional spectrophotometer, which has been saved in an ASCII file to be applied with the WinMLR program. Before to determine sorbic and benzoic acids in samples, the wavelength validation and calibration parameters were studied. Standard solutions of sorbic and benzoic acids were used for the calibration parameters to measure the individual analyte. If the sample has simultaneously both compounds, it is better to choose the synthetic mixture for the calibration parameters. This technique provides a good recovery in the range of 80.4-104.8% without a complicated and expensive instrument.

Evaluation of Exposure to Toluene and Xylene in Gasoline Station Workers

The main volatile organic compounds found at gasoline stations are benzene, toluene, ethylbenzene, and xylene isomers (BTEX). They cause several harmful effects on human health. Regulatory Norm 7 (1978) provides that, in Brazil, biological monitoring of toluene and xylene is carried out by measuring the urinary metabolites hippuric acid (HA) and methylhippuric acid (MHA), respectively. The objective of this study was to assess the exposure to toluene and xylene and to identify related signs and symptoms in gasoline station workers. A cross-sectional epidemiological study was conducted with workers occupationally exposed to fuels. These gasoline station workers were divided into two groups: 94 workers exposed mainly by inhalation (convenience store workers (CSWs)) and 181 workers exposed by inhalation and dermal route (filling station attendants (FSAs)). A comparison group was formed by 119 workers not occupationally exposed to fuels (office workers (OWs)). Workers exposed to fuels had higher average levels of these exposure biomarkers (HA and MHA), which were also higher in convenience store workers than in filling station attendants. In addition, individuals exposed to the solvents present in gasoline had altered mood/depression, cramps, dizziness, drowsiness, headaches, irritability/nervousness, weakness, weight loss, and other symptoms more frequently and had higher urinary levels of HA and MHA compared to the comparison group. Gasoline station workers showed high levels of HA and MHA, reflecting high occupational exposure to the solvents toluene and xylene present in gasoline, demonstrating that changes in the current legislation and in the work environment are necessary to ensure better health protection for these workers.

Determination of Sorbic Acid in Cheese by High Performance Liquid Chromatography

Background

Sorbic acid (E, E-2, 4-hexadienoic acid) is added as a preservative to cheese because of its fungistatic and antimicrobial activity.

Objective

A facile method for the analysis of sorbic acid that is applicable to sliced processed cheese and grated cheese products.

Method

A cheese sample and dry-ice mixture was blended and sorbic acid was extracted with methanol and analyzed by HPLC-ultraviolet with external standardization. A large sample size was used to overcome sample inhomogeneity due to imprecise sorbic acid addition techniques during production and sorbic acid migration through the fat over time.

Results

The method was shown to be accurate for both processed cheese and grated Cheddar cheese, with acceptable spike recovery (93.7, 103.7%, respectively), and no bias (α = 0.05) against an international reference method (p = 0.59, p = 0.13, respectively) was found. Acceptable precision was confirmed for both processed cheese slices and grated Cheddar cheese, with repeatability of 5.3% and 4.3% relative standard deviation, respectively, and intermediate precision Horwitz ratio values of 1.3 and 1.7 for processed cheese slices and grated Cheddar cheese, respectively. Method detection limit and ruggedness experiments further demonstrated the suitability of this method for routine compliance testing.

Conclusions

A method for high-throughput, routine testing of sorbic acid is described. The method was subjected to single-laboratory validation and was found to be accurate, precise, and fit-for-purpose.

Determination of Sorbic Acid in Cheese Samples by Rapid HPLC-DAD Method

The sorbic acid and its salts have been widely used in the food industries for many years as important food preservatives in order to inhibit the growth of various bacteria, yeasts, and fungi in acidic media. The health effects have led to limitation on the concentrations that can be used in food. Because of that, the analytical determination of these preservatives is important for consumer interest and protection. The purpose of this study is to determine the concentration of sorbic acid in cheese samples by using HPLC. For HPLC analysis, an X-Terra RP-18 (150 × 4.60 mm i.d. × 5 μm) column was selected as the stationary phase at 25°C. Analysis time is about 3 minutes. The developed method was applied to 10 different cheese samples collected from the Turkish market. The levels of sorbic acid in the analyzed samples were between 21.3 mg/kg and 511.3 mg/kg.

Rapid analysis of benzoic acid and vitamin C in beverages by paper spray mass spectrometry

A paper spray mass spectrometry (PS-MS) method has been developed for the rapid quantification of benzoic acid (BA) and vitamin C (VC) in beverages. Using BA-d5 as an internal standard (IS) to analyze BA and VC, the calibration curves ranged from 0.3 to 100 μg/mL for BA and 1 to 100 μg/mL for VC, the linearity was 0.9996 for BA and 0.9973 for VC. The limits of detection (LODs) and limits of quantitation (LOQs) were 0.1 μg/mL and 0.3 μg/mL for BA, 0.3 μg/mL and 1 μg/mL for VC, respectively. The recovery ranged from 91.1 to 106.7% for BA, 92.6 to 108.2% for VC. Compared with HPLC, there is no substantial difference in the quantification of BA and VC in samples, the accuracy was 95.7-102.2%, and the run time is far less than that of the HPLC method. The results indicated that PS-MS is a rapid, environmentally friendly and high-throughput method for the quantification of BA and VC.

Synthesis and antimicrobial activities of novel sorbic and benzoic acid amide derivatives

A series of sorbic and benzoic acid amide derivatives were synthesized by conjugating sorbic acid (SAAD, a₁-a₇) or benzoic acid (BAAD b₁-b₆) with amino acid esters and their antimicrobial activities were investigated against Escherichia coli, Bacillus subtilis and Staphylococcus aureus, mixed bacteria from rancid milk, Saccharomyces cerevisiae, and Aspergillus niger. The antimicrobial activity of sorbic acid amides was better than that of benzoic acid amides. The minimum inhibitory concentrations (MIC) of compound isopropyl N-[1-oxo-2, 4-hexadien-1-yl]-L-phenylalaninate (a₇) were 0.17 mM against B. subtilis, and 0.50 mM against S. aureus, while the MIC values of sorbic acid were more than 2 mM respectively. Also, compound a₇ displayed pH-independent antimicrobial activity in the range of pH 5.0-9.0 and was effective at pH 9.0. These results demonstrated that the conjugation of sorbic acid with amino acid esters led to significant improvement of in vitro antimicrobial attributes, but little effect was observed for benzoic acid amide derivatives.

Ecofriendly Fruit Switches: Graphene Oxide-Based Wrapper for Programmed Fruit Preservative Delivery To Extend Shelf Life

According to Food and Agriculture Organization 2015 report, post-harvest agricultural loss accounts for 20-50% annually; on the other hand, reports about preservatives toxicity are also increasing. Hence, preservative release with response to fruit requirement is desired. In this study, acid synthesized in the overripe fruits was envisaged to cleave acid labile hydrazone to release preservative salicylaldehyde from graphene oxide (GO). To maximize loading and to overcome the challenge of GO reduction by hydrazine, two-step activation with ethylenediamine and 4-nitrophenyl chloroformate respectively, are followed. The final composite shows efficient preservative release with the stimuli of the overripe fruit juice and improves the fruit shelf life. The composite shows less toxicity as compared to the free preservative along with the additional scope to reuse. The composite was vacuum-filtered through a 0.4 μm filter paper, to prepare a robust wrapper for the fruit storage.

Capillary electrophoresis to approach sorbate usage in processed meat products in Brazil

Sorbate is a highly used preservative in a wide range of processed foods, including meat products. In this work sorbate usage in commercial processed meat products from the Brazilian market was evaluated. A capillary electrophoresis method for sorbate analysis using ethanol:water extraction solution (1:2, v/v) and sodium tetraborate (20 mmol L^-1) electrolyte solution was validated. Low limits of detection (0.4 mg L^-1) and quantification (1.0 mg L^-1), good precision (RSD = 3.6%) and suitable accuracy (70.2%, RSD = 1.8%) were attained. Linearity was observed from 1.0 to 15.8 mg L^-1, with r ≥ 0.999. The proposed method was applied to Brazilian pork and hot dog sausages, salami, ham and mortadella. A peak of sorbate between 4 and 6 min was found in pork and hot dog sausages, poultry and pork mortadella, but not in ham and salami. The sorbate levels ranged from 54.0 to 976.4 mg kg^-1. Sorbate concentration exceeded the 200 mg kg^-1 limit of the Brazilian legislation in all sorts of products in the majority of the brands despite there being no information regarding sorbate on the label. These results indicated the widespread use of sorbate, turning this into food for thought.

Benzoic acid and its derivatives as naturally occurring compounds in foods and as additives: Uses, exposure, and controversy

Benzoic acid is an aromatic carboxylic acid naturally present in plant and animal tissues, which can also be produced by microorganisms. Benzoic acid and a wide range of derivatives and related benzenic compounds, such as salts, alkyl esters, parabens, benzyl alcohol, benzaldehyde, and benzoyl peroxide, are commonly used as antibacterial and antifungal preservatives and as flavoring agents in food, cosmetic, hygiene, and pharmaceutical products. As a result of their widespread occurrence, production, and uses, these compounds are largely distributed in the environment and found in water, soil, and air. Consequently, human exposure to them can be high, common, and lengthy. This review is mainly focused on the presence and use of benzoic acid in foods but it also covers the occurrence, uses, human exposure, metabolism, toxicology, analytical methods for detection, and legal limits for benzoic acid and its derivatives. Their controversial effects and potential public health concerns are discussed.

Production of benzoic acid as a natural compound in fermented skim milk using commercial cheese starter

In this study, we investigated the production of natural benzoic acid (BA) in skim milk fermentation by 5 kinds of commercial cheese starters. Five kinds of starter were inoculated into 10% reconstituted skim milk, and then the culture was incubated at 2-h intervals for 10 h at 30, 35, and 40°C. In fermentation by MW 046 N+LH 13, the starter for making raclette, BA was highly detected after 8 h at 30 and 35°C. In fermentation by LH 13, the starter for making berg, BA steadily increased and was highly detected at 40°C. In fermentation by TCC-3+TCC-4, the starter for making Caciocavallo and mozzarella, BA was detected after 2 h at 40°C. Also, BA was detected after 4 and 8 h at 35 and 30°C, respectively. In fermentation by Flora-Danica, the starter for making Gouda, BA was increased until 6 h and decreased after 6 h at all temperatures. Among the 5 kinds of fermentation, the level of BA was the highest in fermentation by Flora-Danica at 6 h at 35°C, at 14.55 mg/kg.

Simultaneous Determination of Preservatives in Dairy Products by HPLC and Chemometric Analysis

Cheese and yogurt are two kinds of nutritious dairy products that are used worldwide. The major preservatives in dairy products are sodium benzoate, potassium sorbate, and natamycin. The maximum permitted levels for these additives in cheese and yogurt are established according to Iranian national standards. In this study, we developed a method to detect these preservatives in dairy products by reversed phase chromatography with UV detection in 220 nm, simultaneously. This method was performed on C₁₈ column with ammonium acetate buffer (pH = 5) and acetonitrile (73 : 27 v/v) as mobile phase. The method was carried out on 195 samples in 5 kinds of commercial cheeses and yogurts. The results demonstrated insufficient separation where limit of detection (LOD) and limit of quantitation (LOQ) ranged from 0.326 to 0.520 mg/kg and 0.989 to 1.575 mg/kg in benzoate and sorbate, respectively. The correlation coefficient of each calibration curve was mostly higher than 0.997. All samples contained sodium benzoate in various ranges. Natamycin and sorbate were detected in a remarkable amount of samples, while, according to Iranian national standard, only sorbate is permitted to be added in processed cheeses as a preservative. In order to control the quality of dairy products, determination of preservatives is necessary.

Poly(styrene-co-N-methacryloyl-l-phenylalanine methyl ester)-functionalized magnetic nanoparticles as sorbents for the analysis of sodium benzoate in beverages

In this study, poly(styrene-co-N-methacryloyl-l-phenylalanine methyl ester)-functionalized magnetic nanoparticles were constructed and used as magnetic solid-phase extraction sorbents for analysis of food preservatives in beverages. To prepare the poly(amino acid)-based sorbents, N-methacryloyl-l-phenylalanine methyl ester, and styrene served as the functional monomers and modified onto the magnetic nanoparticles via free radical polymerization. Interestingly, compared with propylparaben and potassium sorbate, the proposed poly(amino acid)-based sorbents showed a good selectivity to sodium benzoate. The adsorption capacity of the sorbents to sodium benzoate was 6.08 ± 0.31 mg/g. Moreover, the fast adsorption equilibrium could be reached within 5 min. Further, the resultant poly(amino acid)-based sorbents were applied in the analysis of sodium benzoate in real beverage samples. The results proved that the proposed magnetic solid-phase extraction sorbents have a great potential for the analysis of preservatives in food samples.

Anion binding studies on receptors derived from the indolo[2,3-a]carbazole scaffold having different binding cavity sizes

The indolo[2,3-a]carbazole scaffold is a fused polyheteroaromatic system bearing two NH groups which suitably converge as hydrogen bond donor sites for the recognition of anions. A simple derivatisation of the indolocarbazole system at positions 1 and 10 with different functional groups, namely alcohols and amides, has contributed to modulate the anion binding selectivity and sensibility. A particularly good response has been obtained for the benzoate anion.