As one of the eight major allergens recognized by the World Health Organization and the Food and Agriculture Organization of the United Nations, it is crucial to determine sesame allergens in food. Employing liquid chromatography-tandem mass spectrometry (LC-MS/MS), which exhibits exceptional precision and sensitivity, enables the identification of sesame allergen proteins. In this investigation, we established and validated a methodology for quantifying sesame allergen protein (Ses i 1-7) in processed foods utilizing LC-MS/MS. The key innovation lies in screening sesame allergen characteristic peptides with processing robustness and using isotope labeled derived peptides as internal standards to correct trypsin digestion efficiency, significantly improving quantitative accuracy. The quantitative method showed excellent sensitivity (limit of detection: 1.0-28 μg/g; limit of quantitation: 2.9-56 μg/g), accuracy (recovery rate: 90%-110%), and repeatability (intra/inter-day precision: 1.06%-7.59%/2.68%-6.98%). In addition, this method has been successfully employed in the examination of commercial food. The quantitative method established in this study is beneficial for the management of sesame allergens in processed foods.

The abuse of opium poppy (Papaver somniferum L.) and its derivatives may lead to addiction and serious health problems. In recent years, cases of illegal addition of opium poppy-derived ingredients to foods have occurred frequently worldwide. For this reason, countries have generally strengthened the control over opium poppy-derived ingredients in foods through legislation, strictly restricting their illegal use in food additives and seasonings, and continuously improving relevant detection technology systems. This article reviews laws and regulations pertaining to opium poppy at home and abroad, focusing on the application of mainstream detection methods such as physicochemical analysis methods, immunoassays and molecular diagnostic techniques. Additionally, it discusses the latest progress and future prospects in opium poppy detection methods. The aim is to provide theoretical support for improving food safety risk prevention and control mechanisms and enhancing regulatory efficiency.

Alpha-lactalbumin (ALA), a significant allergen in cow's milk, requires urgent preventative and therapeutic techniques. Peptide immunotherapy may modify allergic reactivity without cross-linking IgE, making it crucial to milk allergy treatment. In the present study, tolerogenic peptides of α-lactalbumin have been identified by constructing immune cells (MLN cells, splenocytes) from a mouse model of cow's milk allergy and co-culturing them in vitro with candidate peptides. The allergy model demonstrated significant alterations in physiological and biochemical indices within the experimental group. Subsequent co-culture of immune cells with candidate peptides revealed that peptide ALA AA (1-19) induced the expansion of Treg cells and promoted a tolerogenic phenotype in DCs. Taken together, these results led to the successful screening of ALA-tolerant peptides, which inhibited the release of allergy-related cytokines and induced the differentiation of immune cells toward the tolerant phenotype. This study provides a food-compatible peptide strategy for CMA management, with potential applications in hypoallergenic dairy products. Meanwhile, these findings laid the foundation for further validation in subsequent in vivo experiments.

Sesame is one of the eight major allergens that cause food allergies. Study of the epitopes of sesame allergens is important for understanding their sensitization mechanisms. Currently, less information is available on the epitope studies of sesame allergens. In this study, we analyzed the molecular characteristics, structure and homology of Ses i 3, one of the important sesame allergens. We predicted the B-cell linear epitopes of Ses i 3 using bioinformatics tools and characterized them by slot blot immuno-microarrays technology. Eight peptides as B-cell linear epitopes of Ses i 3 were identified, in addition, key amino acids in these epitopes were predicted and leucine 422 was identified as a key amino acid. The present work will contribute to further understanding of the sesame allergen and provide some help in the prevention and treatment of sesame allergy.

To solve the problem of the lack of reference material (RM) for determination of allergenic ingredients in food, a RM of cashew nut powder was developed in the study. Cashew nut powder was prepared from cashew nut kernel by selecting, cleaning, crushing, n-hexane degreasing and sieving treatment. The reliability and traceability of RM was verified using real-time quantitative polymerase chain reaction (qPCR) and phylogenetic tree analysis. The cashew nut powder RM showed good homogeneity, and good stability under long-term storage at 4 ℃ and short-term simulated transportation from –20 to 45 ℃. The RM was determined jointly by 8 collaborative laboratories, and the characteristic C_T value was 24.732, and the extended uncertainty was 1.052% (k = 2). The RM was applied to verify the amplification efficiency and the limit of detection for qPCR assay, and showed good applicability. The RM could be used for method validation and quality control, for the determination of allergenic ingredients in food mixed with trace amounts of cashew nut.

To understand the differential N-glycoprotein characteristics of camel versus cow milk, we employed label-free quantitative N-glycoproteomics to compare the N-glycoprotein composition and the number of N-glycosylation sites between the two milks and utilized bioinformatics tools to predict potential biological functions of their N-glycoproteins. A total of 137 N-glycoproteins harboring 224 N-glycosylation sites were identified in camel milk, and 116 N-glycoproteins with 183 N-glycosylation sites in cow milk. Compared with cow milk, camel milk exhibited greater diversity in both N-glycoprotein types and N-glycosylation site number. Most identified N-glycoproteins contained only one N-glycosylation site, with only a minority displaying hyperglycosylation. Gene Ontology (GO) enrichment analysis revealed that differentially expressed N-glycoproteins were predominantly localized in the extracellular region and extracellular space and played an important role in immune response involving enzymatic activity, extracellular matrix organization, molecular binding, and signal transduction. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that these proteins were mainly enriched in metabolic processes such as complement and coagulation cascades and lysosomal pathways. Collectively, these findings provide molecular-level insights into the differences in N-glycoprotein composition and glycosylation between cow and camel milk.

In the present study, three orange cultivars (Citrus sinensis L. Osbeck), including Trovita, Early-golden, and Hamlin, were selected to produce not from concentrate (NFC) orange juice and from concentrate (FC) orange juice by the commercial manufacturing processes. Eight pairs of primers to obtain targeted fragments of different lengths were designed based on the chloroplast maturase K (matK) and nicotinamide adenine dinucleotide dehydrogenase (ndhF) genes. Polymerase chain reaction (PCR) coupled with capillary electrophoresis (CE) was used to analyze the effects of key processing steps such as extraction, homogenization, pasteurization, concentration, and secondary pasteurization on DNA degradation in the chloroplast matK and ndhF genes in Trovita orange juice. By comparing the differences in DNA degradation between NFC and FC orange juice, we selected the characteristic differential fragment sets and established a PCR-CE method to discriminate between NFC and FC orange juice. The developed method was applicable to analyze NFC and FC orange juice within shelf life. It was equally applicable to discriminate between NFC and FC orange juice manufactured from Early Golden and Hamlin sweet oranges. Finally, this method was used to test commercial NFC orange juice. The results were not consistent with the label information. The PCR-CE method will provide technical support for the effective regulation of the juice industry.

This study aimed to compare the effect of different pretreatment methods for DNA extraction on the bacterial community structure in salami for the purpose of selecting appropriate pretreatment methods for a standardized high-throughput sequencing process. We extracted bacterial DNA from salami by three common pretreatment methods: direct extraction (M0), tapping homogenization (M1), and bead beating (M2). We performed MiSeq high-throughput sequencing of the V3-V4 hypervariable region of the bacterial 16S rRNA gene and analyzed the bacterial community structure based on operational taxonomic units (OTUs). The results showed that a total of 319, 206, and 253 OTUs were observed with M0, M1, and M2, respectively; the number of OTUs shared by the three methods was 129, accounting for 31.85% of the total OTUs. For the three methods, the Chao1 index was 177.93 ± 31.02, 120.76 ± 28.60, and 166.96 ± 15.63, respectively, and the Shannon index was 2.79 ± 0.22, 2.95 ± 0.31, and 3.25 ± 0.30, respectively. At the phylum and family level, the bacterial community structure of the samples obtained by different pretreatment methods was similar despite differential abundance; however, different pretreatment methods affected the results of subsequent community structure analysis at the genus level. M0 increased the abundance and diversity of dominant bacteria, and could be applied to detect bacteria in maturing salami samples. M1 and M2 removed free DNA, leaving only bacterial cells with a complete structure, which could better reflect the bacterial community structure in samples. The bacterial community structure and abundance observed with M1 and M2 for homogeneous samples tended to be consistent. In conclusion, this study shows that different pretreatment methods can affect the results of bacterial community structure analysis. A standardized procedure for high-throughput sequencing should be established as soon as possible to ensure data reliability and the comparability of results across studies.

Milk is rich in a variety of essential nutrients and plays an important role in the growth and development of the human body and immune function. Milk has become indispensable as a highly-frequent consumer goods in people’s daily life. As the bioactive components and nutritional functions of different mammalian milks have been investigated, milk from non-bovine mammals such as camel, donkey, horse, and goat are becoming more and more popular among consumers. In this paper, we summarize and compare the composition and content of major nutrients in bovine, ovine, caprine, equine, donkey and camel milks and their biological functions, which will provide a scientific basis for the development and application of different types of dairy products and the healthy development of the dairy industry.

In this study, the low-level presence of genetically modified (GM) soybean event GTS-40-3-2 was quantitatively detected and the measurement uncertainty was estimated. Within 95% confidence interval, the quantitative method developed using real-time polymerase chain reaction (PCR) and digital PCR could stably detect 0.01% GTS-40-3-2 content with acceptable cost and uncomplicated operation, while the digital PCR method could quantify 0.1% GTS-40-3-2 content accurately, and the quantitative error did not exceed 50% even at GTS-40-3-2 content as low as 0.05%. The sources of uncertainty in quantitative digital PCR analysis were analyzed, and the calculation formula for uncertainty was derived from calculation models in analytical chemistry. Furthermore, GTS-40-3-2 was used for laboratory verification. The expanded uncertainty in quantitative analysis of 0.1% and 0.05% GTS-40-3-2 contents was calculated as 23.56% and 107.29% (k = 2), respectively.