In order to investigate the taste compounds of 18 strong fragrance spices, high performance liquid chromatography was used to determine the content of free amino acids, nucleotides and organic acids. Cluster analysis was used to classify on the basis of similar data. The results showed that the content of free amino acid in tarragon was the highest, 44.97 g/kg, followed thyme, 11.88 g/kg. The contents of organic acids in 3 spice samples were significantly higher compared with others, including thyme (54.67 g/kg), sweet basil (42.28 g/kg) and small cardamon (40.72 g/kg). Nucleotides' contents were significantly higher in star anise (3.54 g/kg) than the other 17 spice samples. The taste active value (TAV) of glutamic acid (22.01) was the highest. In addition, the TAVs of lactic acid, acetic acid, ascorbic acid, tartaric acid and malic acid in 18 spice samples were also more than 1, which indicated that these compounds contribute greatly to spices taste. The equivalent umami concentration (EUC) of tarragon was the highest, with 26.15 g monosodium glutamate (MSG)/100 g. The 18 strong fragrance spices were divided into 2 categories according to the cluster analysis of EUC. The tarragon and dill were one category, other 16 spices were the other category. When the Euclidean distance increased to 25, the tarragon and dill were incorporated into the category of other 16 spices. ARTICLE HISTORY

Spices can be used in cooking to enhance the flavor of food. In order to systematically summarize and discuss the flavor components of 29 elegant spices, the free amino acids, nucleotides, and organic acids in these spices were detected by high‐performance liquid chromatography. Cluster analysis was carried out to classify the 29 elegant spices based on similar data. The results showed considerable variations in the total free amino acids (1.12‒31.59 g/kg), organic acids (9.63‒71.90 g/kg), and nucleotides (0.03‒2.72 g/kg) in the elegant spices. Nine of the amino acids, especially glutamic acid and arginine, were found to have a taste active value (TAV) greater than 1. The TAVs of the 5′‐nucleotides, succinic acid, oxalic acid, tartaric acid, and ascorbic acid were all >1. The equivalent umami concentration (EUC) of sweet marjoram was 83.69 g MSG/100 g. The 29 elegant spices were divided into two categories according to cluster analysis of the EUC. Oregano fell into one category, and the remaining 28 spices fell into the other category.

The aims of this study were to investigate the effect of stewing process on the content of taste compounds in stewing beef broth. The amino acids, 5′‐nucleotides, and organic acids in stewing beef broth were determined by HPLC. The results showed that the contents of four 5′‐nucleotides in raw beef were significantly lower than that in stewed beef broth. The addition of spices, salt, and sucrose was beneficial to promote the release of amino acid in beef broth. The highest contents of umami, sweet amino acid, and total amino acid were 907.67, 2930.11, and 5088.76 μg/g in stewed beef broth with salt addition, and 1085.10, 3367.48, and 5595.20 μg/g with sucrose addition. The contents of those in the stewed beef optimal group (s‐b‐o) were 7008.53, 34007.67, and 49282.82 μg/g, respectively, which was far higher than that with salt addition and sucrose addition. The content of total amino acid and total organic acid was significantly higher in s‐b‐o‐o than in s‐b‐o. The proper amount of blend oil was beneficial to the release of flavor substances in stewed beef broth. The EUC value of the stewed beef blank group (s‐b‐b) was 3.50 g MSG/100 g. The addition of spices could significantly increase the EUC of stewed beef broth. The TAVs of 8 compounds were more than 1 in the sample of s‐b‐o‐o, including Asp, Glu, Pro, Ala, Val, Met, Arg, and tartaric acid. These 8 compounds contribute more to the taste of stewed beef broth.

Beef is popular meat, rich in protein and delicious taste. Good stir-fried conditions could make the beef more nutritious and delicious. In this work, the optimization of stir-fried condition was studied through orthogonal method. Separation procedures utilizing ultrafiltration, Sephadex G-15 and reversed-phase high-performance liquid chromatography were used to isolate umami taste peptides. The range analysis of orthogonal methods indicated that the stir-fried time was the main factor in the taste efficiency of sensory evaluation, followed by sucrose, oil, and finally was the salt. Combined with sensory evaluation and LC-Q-TOF/MS, the amino acid sequences of five oligopeptides were identified in optimized stir-fried beef, included VAPEEHPT, LAPSTM, PECGLVVG, FADNVFAL, FAGDDAPR. There were 4 eight-peptide and 1 six-peptide. The 15 amino acids were identified in these five peptides. In the five peptides, the Pro appeared 5 times, Val and Ala appeared 4 times, Glu, Leu, Gly, Phe, and Asp appeared 3 times. The amino acid residues of Glu-Glu (EE)-continuous and Asp-Asp (DD)-continuous in the polypeptide of stir-fried beef were identified. Double umami amino acid-continuous could be important for the umami taste of peptide.

High-performance liquid chromatography was used to determine the important taste compounds in 20 pungent spices commonly used in food, including seventeen free amino acids, four 5′-nucleotides and twelve organic acids. The equivalent umami concentration (EUC) and taste activity value (TAV) of the analyzed samples were calculated. The results showed that the content of total free amino acids ranged from 0.57 to 46.67 g/kg in 20 pungent spices. The content of total free amino acids in horseradish was the highest. The content of total 5′-nucleotides ranged from 0.80 to 4.30 g/kg, and chive contains the highest 5′-nucleotide content. Inosine 5′-monophosphate was detected in all 20 pungent spices. The content of total organic acids ranged from 9.37 to 339.58 g/kg. The total organic acids content of fieldmint was the highest (339.58 g/kg). Oxalic acid was detected in 18 pungent spices, except white pepper and chilli. The EUC of fieldmint (37.1 g MSG/100 g) was the highest in all 20 pungent spices, followed with peppermint (24.5 g MSG/100 g), and horseradish (18.4 g MSG/100 g). The TAVs of malic acid, lactic acid and 5′-AMP were higher than 1 in more than 10 spices. Lactic acid were higher than 1 in 13 spices, implying these compounds contributed greater to the flavor of pungent spices. The results of this work will provide references for the application value of pungent spices.