Identification and characterization of the aroma-impact components of Thai fish sauce

Changes in the chemical properties and metabolite profiling of fish sauce prepared from underutilized large yellow croaker roes during fermentation at different temperatures

Fish sauce is a popular aquatic condiment with unique flavor. In this study, the changes in the chemical properties and metabolite profiling of fish sauce from large yellow croaker roes during fermentation at different temperatures were revealed. The results found that the contents of total acid, amino acid nitrogen, total soluble nitrogen and soluble salt-free solids of fish sauce fermented at 40 °C were higher than those in other temperatures groups (25 °C and 32 °C), while the contents of total volatile basic nitrogen were lower than other temperatures. Therefore, 40 °C was the ideal fermentation temperature for fish sauce. The metabolomics analysis showed that organic acids, amino acids, nucleotide, and lipid compounds were found to participate in the biosynthesis pathway. Compared to 25 °C and 32 °C, fermented at 40 °C could increase the abundance of metabolic substances in the fish sauce, such as sugar alcohols, L-Citrulline, L-Aspartic acid, L-Cysteine, Glutathione, and L-Arginine. These results provide a theoretical basis for the production of high-quality fish sauce and the high-value utilization of fish roes.

The Impact of Sea Urchin as an Ingredient on the Physicochemical, Microbiological, and Sensory Properties of Fish Sauce Fermentation

The consequences of using 25% whole or shelled sea urchin as an ingredient in anchovy sauce on its fermentation and development of its physicochemical properties after 20 days fermentation was studied. Two varieties of fish and sea urchin sauce were made with or without shell at 1:2:1 ratio (salt:fish:sea urchin) plus a control fish sauce at 1:3 ratio (salt:fish). All sauces were fermented at 40-50 °C for 20 days, where for the first 7 days the preparation remained in a static phase. During their fermentation, pH, salt concentration, aw, TVB-N, TMA, total nitrogen, formaldehyde nitrogen, amino nitrogen, and ammonium nitrogen, as well as aerobic mesophiles and lactic acid bacteria were monitored. The fermentation of the experimental sauces proved to follow an evolution rather similar to the control sauce. The whole and shelled sea urchins provided the necessary microbial and enzymatic load to trigger an adequate hydrolysis of the fish and the production of total nitrogen (16.0-17.6 g/L), formaldehyde nitrogen (15.1-16.0 g/L), and amino nitrogen (0.7-0.8 g/L) of the same order as the control sauce, despite the lower fish content. According to TMA (9.2-13.1 mg N/100 g), VBT (40.0-47.2 mg N/100 g) contents, and pH levels (5.41-5.46), no deviation of the fermentation process was observed under the experimental conditions (salt content, temperature, and agitation after the static phase). Quantitative descriptive analysis (QDA) sensory revealed that the use of sea urchin results in high quality products characterized by their aromas of crustaceans and mollusks. The present study investigates the potential use of shelled and even whole sea urchin as an ingredient for the preparation of high quality fish sauces.

Identification of Important Aroma Components and Sensory Profiles of Minimally Processed (Unroasted) and Conventionally Roasted Dark Chocolates

Roasting is an important unit operation for the development of characteristic chocolate aroma during manufacturing. However, there is an increase in interest in minimally processed chocolate products due to their potential positive health benefits. The odor-important compounds and sensory characteristics of minimally processed (unroasted) and conventionally roasted dark chocolates were determined by gas chromatography-olfactometry, aroma extract dilution analysis (AEDA), and stable isotope dilution analysis (SIDA). Except for acetic acid, all odorants had higher odor-activity values (OAVs) in roasted chocolate. Acetic acid, developed during fermentation and drying, had the highest OAV in both chocolates but was better preserved in unroasted chocolate. Compounds making a greater aroma impact on roasted chocolate compared with unroasted chocolate included dimethyl trisulfide, 2-ethyl-3,5-dimethylpyrazine, and 3-methylbutanal. Nine significant sensory attributes in unroasted and roasted chocolates were identified. Vinegar (aroma) and roasted (aroma and aroma by mouth), sweet (taste), and hardness (texture) attributes differed between unroasted and roasted chocolates. The results of this study enforce the embracement of low thermal processes to showcase the inherent flavor potential of cacao beans but also to support the concept of chocolate "terroir" by potentially preserving important aroma compounds developed during fermentation.

Comparison of Commercial Fish Proteins' Chemical and Sensory Properties for Human Consumption

To stop overfishing and meet the protein needs of a growing population, more information is needed on how to use marine by-catches, by-products, and undervalued fish species for human consumption. Turning them into protein powder is a sustainable and marketable way to add value. However, more knowledge of the chemical and sensory properties of commercial fish proteins is needed to identify the challenges in developing fish derivatives. This study aimed to characterize the sensory and chemical properties of commercial fish proteins to compare their suitability for human consumption. Proximate composition, protein, polypeptide and lipid profiles, lipid oxidation, and functional properties were analyzed. The sensory profile was compiled using generic descriptive analysis, and odor-active compounds were identified with gas-chromatography-mass spectrometry-olfactometry (GC-MS/O). Results indicated significant differences in chemical and sensory properties between processing methods but not between fish species. However, the raw material had some influence in the proteins' proximate composition. Bitterness and fishiness were the main perceived off-flavors. All samples, apart from hydrolyzed collagen, had intense flavor and odor. Differences in odor-active compounds supported the sensory evaluation results. The chemical properties revealed that the lipid oxidation, peptide profile, and raw material degradation are likely affecting the sensory properties of commercial fish proteins. Limiting lipid oxidation during processing is crucial for the development of mild-tasting and -smelling products for human consumption.

Rapid Production of Fish Sauce from the Internal Organs of White Sturgeon, Acipenser transmontanus Richardson, 1836

The internal organs of white sturgeon in Miyazaki Prefecture are discarded during processing. Therefore, we tried to produce fish sauce using a short-term manufacturing method. The minced internal organs were autolyzed by endogenous proteases at 50 °C. During autolysis, the protein contents of the supernatant and precipitate after centrifugation were analyzed by the Kjeldahl method, and the protein size was monitored by SDS-PAGE. This analysis showed that the extraction rate was about 60% after treatment at 50 °C for 24 h. The major bands at 200 kDa, 43 kDa, and 40 kDa detected before the start of the treatment gradually disappeared over time. Fifteen components were detected as the main volatile components. These components increased sharply and then decreased during incubation at 50 °C for 24 h. The fish sauce produced had a good aroma after incubation at 50 °C for 72 h.

Characterization of the Key Aroma Constituents in Fried Tilapia through the Sensorics Concept

The object of this study was tilapia fish that were fried in soybean oil. Volatile compounds were extracted from the fish by ASE-HVE and were studied by GC-O-MS and the AEDA analysis method. A total of 30 aroma compounds were initially determined, and these compounds contribute to the aroma of fried tilapias. The key volatile compounds in fried tilapia were quantitatively analyzed by GC-MS, and the volatile compounds in soybean-fried tilapia were studied by flavor recombination and deletion experiments. Trimethylamine, hexanal, 2,3-dimethylpyrazine, dimethyl trisulfide, trans-2-octenal, 2,3-dimethyl-5-ethylpyrazine, (E)-2-nonenal, 2-propyl-pyridine, and (E,E)-2,4-decadienal were finally determined to be the key volatile compounds in soybean-fried tilapia.

Enzyme-Assisted Extraction of Fish Oil from Whole Fish and by-Products of Baltic Herring (Clupea harengus membras)

Baltic herring (Clupea harengus membras) is one of the most abundant commercially caught fish species from the Baltic Sea. Despite the high content of fat and omega-3 fatty acids, the consumption of Baltic herring has decreased dramatically over the last four decades, mostly due to the small sizes and difficulty in processing. At the same time there is an increasing global demand for fish and fish oil rich in omega-3 fatty acids. This study aimed to investigate enzyme-assisted oil extraction as an environmentally friendly process for valorizing the underutilized fish species and by-products to high quality fish oil for human consumption. Three different commercially available proteolytic enzymes (Alcalase^®, Neutrase^® and Protamex^®) and two treatment times (35 and 70 min) were investigated in the extraction of fish oil from whole fish and by-products from filleting of Baltic herring. The oil quality and stability were studied with peroxide- and p-anisidine value analyses, fatty acid analysis with GC-FID, and volatile compounds with HS-SPME-GC-MS. Overall, longer extraction times led to better oil yields but also increased oxidation of the oil. For whole fish, the highest oil yields were from the 70-min extractions with Neutrase and Protamex. Protamex extraction with 35 min resulted in the best fatty acid composition with the highest content of eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) but also increased oxidation compared to treatment with other enzymes. For by-products, the highest oil yield was obtained from the 70-min extraction with Protamex without significant differences in EPA and DHA contents among the oils extracted with different enzymes. Oxidation was lowest in the oil produced with 35-min treatment using Neutrase and Protamex. This study showed the potential of using proteolytic enzymes in the extraction of crude oil from Baltic herring and its by-products. However, further research is needed to optimize enzymatic processing of Baltic herring and its by-products to improve yield and quality of crude oil.

New insights into the flavoring potential of cricket (Acheta domesticus) and mealworm (Tenebrio molitor) protein hydrolysates and their Maillard products

Insect proteins have an earthy-like flavor and have not shown great flavor potential for food applications so far. In this study, insect proteins of cricket Acheta domesticus and mealworm Tenebrio molitor larvae were first enzymatically hydrolyzed using two peptidase preparations (Flavourzyme1000L and ProteaseA "Amano"2SD). Xylose was then added to facilitate Maillard reactions (30 min, T = 98 °C, 1% (w/v) xylose). A comprehensive sensory evaluation showed that both the hydrolysis and the Maillard reactions changed the flavor description of the samples significantly to more complex and savory-like taste profiles (27 descriptors for cricket and 39 descriptors for mealworm protein). In addition, 38 odor-active molecules were identified using gas chromatography-olfactometry (1 alcohol, 5 acids, 11 aldehydes, 5 ketones and 16 heterocyclic compounds). The results showed impressively that the flavoring potential of insect proteins was significantly enhanced with respective processing.

Comparative Characterization of Aroma Compounds in Silver Carp (Hypophthalmichthys molitrix), Pacific Whiting (Merluccius productus), and Alaska Pollock (Theragra chalcogramma) Surimi by Aroma Extract Dilution Analysis, Odor Activity Value, and Aroma Recombination Studies

Aroma compounds in three surimi samples, made from freshwater silver carp (Hypophthalmichthys molitrix) and saltwater Pacific whiting (Merluccius productus) and Alaska pollock (Theragra chalcogramma), were characterized by aroma extract dilution analysis, odor activity value, and odor recombination study. Results demonstrated that the most potent aroma-active compounds in the surimi were hexanal, (Z)-4-heptenal, (Z)-4-decenal, (E,Z)-2,6-nonadienal, (E,E)-2,4-nonadienal, (E,Z)-2,4-decadienal, (E,E)-2,4-decadienal, (E,E,Z)-2,4,6-nonatrienal, (E,Z,Z)-2,4,7-tridecatrienal, and (E)-4,5-epoxy-(E)-2-decenal, contributing fishy, green, oily, or metallic odors. The other aroma contributors in surimi were 1-octen-3-one, 1-octen-3-ol, dimethyl disulfide, dimethyl trisulfide, and methional. 2-Acetyl-1-pyrroline, giving a typical popcorn note, could also be an important aroma contributor as a result of the high flavor dilution factor. Pacific whiting and Alaska pollock surimi samples both had higher levels of dimethyl trisulfide and methional, whereas the silver carp surimi sample had more (E,Z)-2,4-decadienal. In general, the silver carp surimi sample had more aldehydes contributing stronger "river water, fishy" and "grassy, green" aromas. In contrast, saltwater surimi showed stronger "sea breeze-like" and "sulfur-like" odors.

Comprehensive investigation on volatile and non-volatile metabolites in broccoli juices fermented by animal- and plant-derived Pediococcus pentosaceus

A metabolomics approach was employed to investigate differences and correlations among key odorants and non-volatile metabolites in broccoli juices fermented by plant- and animal-derived Pediococcus pentosaceus. Forty volatile metabolites were identified by headspace solid-phase microextraction/gas chromatography-mass spectrometry. According to orthogonal projections to latent structures-differential analysis, 24 and 21 differential volatiles were detected after fermentation by plant- and animal-derived P. pentosaceus, respectively. The concentrations of 10 odorants (OAV ≥ 1) detected by gas chromatography-olfactometry changed significantly after fermentation by P. pentosaceus. Using ultrahigh-pressure liquid chromatography/quadrupole time-of-flight mass spectrometry, 49.47% of the non-volatile metabolites were classified as lipids and lipid-like molecules. The relative expressions of five non-volatile metabolites that exhibited significant correlations with odorants using Spearman correlation analysis changed significantly after fermentation. Fermentation with animal- and plant-derived P. pentosaceus can therefore change key odorants and non-volatile metabolites in broccoli juice that contribute to the characteristic organoleptic properties of products.

Volatile compounds, physicochemical and sensory characteristics of Colatura di Alici, a traditional Italian fish sauce

BACKGROUND

The present study reports for the first time the physical, chemical and sensory characterization of a traditional fish sauce from Italy, called 'Colatura di Alici', which is considered to be the direct descendant of the ancient roman sauce 'Garum'.

RESULTS

Among the volatile compounds, carboxylic acids, aldehydes, sulphuric compounds and pyrazines were identified. The most abundant compounds identified were 3-methyl-butanoic acid, nonanal and 3-methyl-butanal. The sample A had the highest amount of volatile fatty acids (>250 μg kg^-1 ) and sample B had the highest concentration of aldehydes (>80 μg kg^-1 ). These volatile compounds arise from the long fermentation activity and oxidation of fatty acids of the fish flesh and are responsible for the strong cheesy and fishy aroma. The protein content ranged from 90 to 130 g kg^-1 , and the soluble solids ranged from 30 to 38 °Brix, as a result of the high amount of NaCl used during processing. The sensory analysis showed a great intensity for the cheesy, fishy and umami attributes, and a medium intensity for the roasted and meaty attributes.

CONCLUSION

For the first time, the volatile compounds and sensory characteristics of this traditional fish sauce are reported. The samples differ in terms of sensory and aromatic profiles. These differences are probably linked to the poorly standardized methods used in the production process. Overall, the results of the present study could be used by local fish sauce producers to monitor the quality of the product and to improve the production process. © 2020 Society of Chemical Industry.

Correlation between autochthonous microbial communities and key odorants during the fermentation of red pepper (Capsicum annuum L.)

High-throughput sequencing and gas chromatography-mass spectrometry (GC-MS) were used to investigate changes in bacterial and fungal communities and volatile flavor compounds during a 32-day fermentation process of red pepper (Capsicum annuum L.). Key odorants were identified by olfactometry combined with GC-MS. Sixteen volatile compounds differed significantly after fermentation, including seven odorants. After fermentation, 1-butanol, 3-methyl-, acetate, phenol, 4-ethyl-2-methoxy-, octanoic acid, ethyl ester, styrene and 2-methoxy-4-vinylphenol were the key odorants, producing a flavor described as peppery, fruity, sour, and spicy. The correlation between microorganisms and odorants in the fermentation was studied and 18 odorants significantly correlated with the core microbial communities in the fermented samples. For further analysis, strains of seven genera were isolated and correlation analysis by O2PLS indicated that Aspergillus, Bacillus, Brachybacterium, Microbacterium and Staphylococcus were highly correlated with the flavor formation. These findings would help to understand the fermentation mechanism of fermented red pepper flavor formation.

Identification of Characterizing Aroma Components of Roasted Chicory "Coffee" Brews

The roasted and ground root of the chicory plant (Cichorium intybus), often referred to as chicory coffee, has served as a coffee surrogate for well over 2 centuries and is still in common use today. Volatile components of roasted chicory brews were identified by direct solvent extraction and solvent-assisted flavor evaporation (SAFE) combined with gas chromatography-olfactometry (GC-O), aroma extract dilution analysis (AEDA), and gas chromatography-mass spectrometry (GC-MS). A total of 46 compounds were quantitated by stable isotope dilution analysis (SIDA) and internal standard methods, and odor-activity values (OAVs) were calculated. On the basis of the combined results of AEDA and OAVs, rotundone was considered to be the most potent odorant in roasted chicory. On the basis of their high OAVs, additional predominant odorants included 3-hydroxy-4,5-dimethyl-2(5H)-furanone (sotolon), 2-methylpropanal, 3-methylbutanal, 2,3-dihydro-5-hydroxy-6-methyl-4H-pyran-4-one (dihydromaltol), 1-octen-3-one, 2-ethyl-3,5-dimethylpyrazine, 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF), and 3-hydroxy-2-methyl-4-pyrone (maltol). Rotundone, with its distinctive aromatic woody, peppery, and "chicory-like" note was also detected in five different commercial ground roasted chicory products. The compound is believed to an important, distinguishing, and characterizing odorant in roasted chicory aroma. Collectively, a group of caramel- and sweet-smelling odorants, including dihydromaltol, cyclotene, maltol, HDMF, and sotolon, are also thought to be important aroma contributors to roasted chicory aroma.

Quantitation of Three Strecker Aldehydes from Enzymatic Hydrolyzed Rice Bran Protein Concentrates as Prepared by Various Conditions

The quantitation of three Strecker aldehydes-2-methypropanal (2-MP), 2-methylbutanal (2-MB), and 3-methylbutanal (3-MB)-from rice bran protein hydrolysate (RBPH) prepared under various conditions were investigated. The preparation conditions included hydrolysis time (0, 0.25, 2, 4, or 8 h), pH adjustment (pH 4.0, 7.0, or 10.0), and sugar addition (sucrose, glucose, or fructose). These conditions provide a significant potential for aroma generation from the Strecker degradation and Maillard reaction. The Strecker aldehyde quantitation was performed using gas chromatography (GC) with cryo-focusing technique. These combined techniques encourage the precise 2-MB and 3-MB quantitation. The highest concentrations of three Strecker aldehydes were found in RBPH that was prepared by alcalase hydrolysis at 4 h with fructose addition (RBPH-F) and adjusted to pH 7.0 before spray drying. Thirty-nine aroma-active compounds of RBPH-F were discovered using solid-phase microextraction coupled with GC-olfactometry.

Shortening Fermentation Period and Quality Improvement of Fermented Fish, Chouguiyu, by Co-inoculation of Lactococcus lactis M10 and Weissella cibaria M3

Chouguiyu, a Chinese traditional fermented fish, is famous for its uniquely strong odor and desirable taste. However, traditional spontaneous fermentation often resulted in contamination and unstable quality of products. In this study, individual or conjunctive inoculation of two indigenous lactic acid bacteria (LAB), Lactococcus lactis M10 and Weissella cibaria M3, was tested for their effect on improving Chouguiyu's quality. It was shown that inoculation would not affect the system's pH, while increased the total bacteria count and lactic acid bacteria amounts. Matrix-assisted laser desorption/ionization time-of-flight mass (MALDI-TOF) analysis results revealed that Lactoc. lactis M10 and W. cibaria M3 could quickly occupy a dominant position in the ecosystem, and Lactoc. lactis M10 played an important role in the control of spoilage bacteria. Volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and biogenic amines results also showed that Lactoc. lactis M10 had a positive effect on improving the product's quality. Co-inoculation of Lactoc. lactis M10 and W. cibaria M3 could promote the formation of flavor according to the E-nose and gas chromatography-mass spectrometer (GC-MS) analyses, especially for the aroma-active and key volatile compounds. PCA plots of E-nose and hierarchical clustering analysis of GC-MS profiles revealed that the co-inoculation sample at the fifth day (LW5) was the most similar to the natural fermentation sample at the seventh day (C7). The overall acceptance of LW5 was also the closest to that of C7 in sensory evaluation. In conclusion, mixed starter culture was shown to have a good effect on improving product quality and enhancing flavor with fermentation time shortened by 29%.

Identification of Ginger (Zingiber officinale Roscoe) Volatiles and Localization of Aroma-Active Constituents by GC-Olfactometry

For the characterization of chemical components contributing to the aroma of ginger, which could benefit the development of deep-processed ginger products, volatile extracts were isolated by a combination of direct solvent extraction-solvent-assisted flavor evaporation and static headspace analysis. Aroma-impact components were identified by gas chromatography-olfactometry-mass spectrometry, and the most potent odorants were further screened by aroma extract dilution analysis (AEDA) and static headspace dilution analysis (SHDA). The AEDA results revealed that geranial, eucalyptol, β-linalool, and bornyl acetate were the most potent odorants, exhibiting the highest flavor dilution factor (FD factor) of 2187. SHDA indicated that the predominant headspace odorants were α-pinene and eucalyptol. In addition, odorants exhibiting a high FD factor in SHDA were estimated to be potent aroma contributors in AEDA. The predominant odorants were found to be monoterpenes and sesquiterpenes, as along with their oxygenated derivatives, providing minty, lemon-like, herbal, and woody aromas. On the other hand, three highly volatile compounds detected by SHDA were not detected by AEDA, whereas 34 high-polarity, low-volatility compounds were identified only by AEDA, demonstrating the complementary natures of SHDA and AEDA and the necessity of utilizing both techniques to accurately characterize the aroma of ginger.

Characterisation of aroma-active and off-odour compounds in German rainbow trout (Oncorhynchus mykiss). Part I: Case of aquaculture water from earthen-ponds farming

Comprehensive analyses were accomplished to explore the odorous molecules responsible for off-odour development in earthen-ponds rainbow trout (Oncorhynchus mykiss) aquaculture farming in Germany. In this part of the study, water odorants were extracted using solvent-assisted flavour evaporation (SAFE); then, extracts were analysed by one- and two- dimensional high resolution gas chromatography coupled with olfactometry and mass spectrometry using two columns with different polarity (DB-FFAP and DB-5). Aroma extract dilution analysis (AEDA) of the solvent extract samples revealed 54 odorants, and 47 of them were identified. In this study, a series of compounds is described for the first time in German earthen-ponds rainbow trout aquaculture water including, amongst others, 4-hydroxy-2,5-dimethyl-3(2H)-furanone (furaneol), vanillin, (E)-4,5-epoxy-(E)-2-decenal, 4-ethyloctanoic acid, 3-methylindole (skatole), 5α-androst-16-en-3-one (androstenone), and 2-(2-butoxyethoxy) ethanol. Moreover, the sensory experiment indicated that (E)-4,5-epoxy-(E)-2-decenal, (E,E)-2,4-octadienal, and 1-octen-3-one are the main contributors to the metallic, cucumber, and mushroom notes of the samples.

Comparative Analysis of Volatile Composition in Chinese Truffles via GC × GC/HR-TOF/MS and Electronic Nose

To compare the volatile compounds of Chinese black truffle and white truffle from Yunnan province, this study presents the application of a direct solvent extraction/solvent-assisted flavor evaporation (DSE-SAFE) coupled with a comprehensive two-dimensional gas chromatography (GC × GC) high resolution time-of-flight mass spectrometry (HR-TOF/MS) and an electronic nose. Both of the analytical methods could distinguish the aroma profile of the two samples. In terms of the overall profile of truffle samples in this research, more kinds of acids were detected via the method of DSE-SAFE. Besides, compounds identified in black truffle (BT), but not in white truffle (WT), or vice versa, and those detected in both samples at different levels were considered to play an important role in differentiating the two samples. According to the analysis of electronic nose, the two samples could be separated, as well.

Dimethyl trisulfide: A novel cyanide countermeasure

In the present studies, the in vitro and in vivo efficacies of a novel cyanide countermeasure, dimethyl trisulfide (DMTS), were evaluated. DMTS is a sulfur-based molecule found in garlic, onion, broccoli, and similar plants. DMTS was studied for effectiveness as a sulfur donor-type cyanide countermeasure. The sulfur donor reactivity of DMTS was determined by measuring the rate of the formation of the cyanide metabolite thiocyanate. In experiments carried out in vitro in the presence of the sulfurtransferase rhodanese (Rh) and at the experimental pH of 7.4, DMTS was observed to convert cyanide to thiocyanate with greater than 40 times higher efficacy than does thiosulfate, the sulfur donor component of the US Food and Drug Administration-approved cyanide countermeasure Nithiodote^® In the absence of Rh, DMTS was observed to be almost 80 times more efficient than sodium thiosulfate in vitro The fact that DMTS converts cyanide to thiocyanate more efficiently than does thiosulfate both with and without Rh makes it a promising sulfur donor-type cyanide antidote (scavenger) with reduced enzyme dependence in vitro The therapeutic cyanide antidotal efficacies for DMTS versus sodium thiosulfate were measured following intramuscular administration in a mouse model and expressed as antidotal potency ratios (APR = LD₅₀ of cyanide with antidote/LD₅₀ of cyanide without antidote). A dose of 100 mg/kg sodium thiosulfate given intramuscularly showed only slight therapeutic protection (APR = 1.1), whereas the antidotal protection from DMTS given intramuscularly at the same dose was substantial (APR = 3.3). Based on these data, DMTS will be studied further as a promising next-generation countermeasure for cyanide intoxication.