RESUMO
Cooking improves food aroma, but few studies have explored how cooking affects food aromas. Here, aroma changes in mildly salted large yellow croaker (Larimichthys crocea, MSLYC) after steaming, baking, frying, and deep frying was investigated. The raw fish was dominated by fishy notes but after cooking, the aroma became dominated by fatty notes. Nine volatiles, including hexanal, nonanal, (E, Z)-2, 6-nonadienal, (E, E)-2, 4-decadienal, 1-octen-3-ol, linalool, ethyl hexanoate, acetic acid and anethole, were identified as key odor-active compounds using GC-MS, OAV, and omission tests analyses. Changes in the concentrations of key odor-active compounds were mainly due to evaporation, oxidation of linolenic acids, and thermal catalyzed reactions. Interestingly, anethole was the key odor-active compound, providing new insight into the underlying reactions of cooked fish aroma.
Assuntos
Perciformes , Compostos Orgânicos Voláteis , Animais , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Culinária/métodos , Ácidos LinolênicosRESUMO
Spirulina platensis is a high-nutrient blue-green alga with a long history as a food supplement. In this study, the mixed fermentation of Spirulina with Lactobacillus plantarum and Bacillus subtilis was investigated using random-centroid optimization to improve deodorization of off-flavor and hydrolysis of protein. Fermented Spirulina with the maximum total viable counts of both organisms achieved best sensory characteristics and degree of proteolysis among those with different maximum biomass. The mixed fermentation noticeably reduced the volatile compounds of Spirulina, and yielded the highest relative contents (>85%) of acetoin and other odorants collectively producing a creamy aroma. Approximately one-third of the Spirulina proteins were hydrolyzed, yielding over 16% polypeptides and increasing the ratio of essential amino acids to total free amino acids to 1.5-fold compared with unfermented Spirulina. Fermentation with B. subtilis and L. plantarum effectively improved the odor and protein availability of Spirulina.
Assuntos
Bacillus subtilis/fisiologia , Lactobacillus plantarum/fisiologia , Spirulina/fisiologia , Acetoína/análise , Acetoína/metabolismo , Aminoácidos/metabolismo , Suplementos Nutricionais , Fermentação , Humanos , Hidrólise , Microbiologia Industrial/métodos , Odorantes/análise , Spirulina/química , Paladar , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismoRESUMO
Germination favors to significantly enhance functional components and health attributes of whole-grain brown rice (BR), but the production of germinated BR (GBR) compromises the typical rice flavor perception due to soaking process. Simultaneously, high hydrostatic pressure (HHP) is considered as an effective processing technique to enhance micronutrients utilization efficiency of GBR and improve products flavor, but no information about the effects of HHP treatments on volatile fingerprinting of GBR has been reported. Therefore, the objective of this work was to apply HHP to improve the flavor and odor of GBR grains by exploring HHP-induced changes in aroma compounds. GBR grains were obtained by incubating at 37°C for 36h, and subsequently subjected to HHP treatments at pressures 100, 300 and 500MPa for 15min, using 0.1MPa as control. Headspace solid-phase micro extraction coupled to gas chromatography mass spectrometry was used to characterize process-induced shifts of volatile organic compounds fingerprinting, followed by multivariate analysis. Our results confirmed the significant reduction of total volatile fractions derived from germination process. Contrarily, the following HHP treatments greatly enhanced the flavor components of GBR, particularly characteristic odorants including aldehydes, ketones, and alcohols. Principal component analysis further indicated the different influence of germination and high pressure on the changes in volatile components. Partial least square-discrimination analysis suggested that 4-vinylguaiacol was closely linked to germination, whereas E,E-2,4-decadienal, E-2-hexenal, E,E-2,4-heptadienal and benzyl alcohol could be considered as volatile biomarkers of high pressure.
Assuntos
Manipulação de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Germinação , Oryza , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/análise , Pressão Hidrostática , Odorantes , Paladar , Temperatura , Fatores de TempoRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: The hip of Rosa multiflora Thunb. (HRM) has been traditionally used as a dietary supplement and a herbal remedy for the treatment of various diseases, including inflammation, osteoarthritis, rheumatoid arthritis and chronic pain, in China. The current study was to evaluate the therapeutic efficacy of the petroleum ether extractive of HRM (PEE) on type II collagen-induced rheumatoid arthritis (CIA) in male Wistar rats. In addition, the anti-inflammatory mechanism(s) of PEE on type II CIA was explored. MATERIALS AND METHODS: Rheumatoid arthritis (RA) was induced by intradermal injection of bovine type II collagen on Day 1 and Day 8. Starting from Day 13, normal rats were treated with vehicle (serving as the control group); the CIA rats were treated with vehicle (CIA group), dexamethasone (0.25mg/kg bw per day, p.o.) (a positive control), lei-gong-teng (LGT: 10mg/kg bw per day, p.o.) (a clinically used Chinese patent medicine in RA therapy) or PEE (12, 36 or 120mg/kg bw per day, p.o.) for 28 days. RESULTS AND CONCLUSIONS: PEE (120mg/kg bw per day) efficiently attenuated the severity of arthritis in the CIA rats by reducing the mean arthritis severity scores and the fore/hind paw swelling as well as reduced histological changes by decreasing the cartilage surface erosion and cartilage proteoglan depletion. PEE׳s therapeutic effect in RA may involve the inhibition of pro-inflammatory cytokines, such as TNF-α, IL-1ß and IL-6, in serum and/or the elevation of the activities of hepatic anti-oxidative enzymes including SOD, CAT and GSH-Px. However, the detailed anti-inflammatory mechanism, the main effective components and the interaction between different ingredients in PEE are still not clear and require more studies.