Characteristic Odor Research Articles

Odor Characteristics of Volatile Fractions Prepared from Pork Meat Assessed by a Trained Panel using Check-All-That-Apply Questions

Odor Characteristics of Volatile Fractions Prepared from Pork Meat Assessed by a Trained Panel using Check-All-That-Apply Questions

Characterization of the key odorants in Amomum tsao-ko cobs by sensory directed flavor analysis

To decode the key odorants in Amomum tsao-ko cobs (ATC) and to examine the impact of extraction methods on key odorants, volatiles of ATC were isolated by both hydrodistillation (HD) and solvent extraction combined with solvent-assisted flavor evaporation (SE-SAFE). In total, 49 aroma-active compounds with flavor dilution (FD) factors between 1 and 8192 were detected by gas chromatography–olfactometry-mass spectrometry, of which 39 and 42 odorants were identified in the HD and SAFE extracts, respectively. The 34 odorants (FD ≥ 16) were further quantitated; odor activity value calculations, aroma reconstitution and omission experiments were conducted to evaluate their contributions to the characteristic odor of ATC, and 11 compounds were confirmed as key odorants of ATC. Furthermore, the majority of the potent odor-active compounds in the two extracts were identical, but their concentrations were significantly different. The outcomes will give a theoretical foundation for developing and utilizing ATC.

Chemosensoric approaches for taste and odor characteristics each broccoli floret by different storage conditions analyzed using electronic sensors.

This study was to identify taste and volatile characteristics in broccoli florets under various storage conditions (room and cold temperatures). Electronic tongue (E-tongue) analysis revealed that the differences were not represented obviously according to the storage temperatures. The sourness sensor (SRS) was the highest in the 2nd week, and the saltiness sensor (STS) was the highest in the 1st week. The umami (UMS) and bitterness sensors (BRS) were the highest in the 3rd week, and the sweetness sensor (SWS) was the highest in the initial sample. Clusters were discriminated according to storage periods, regardless of storage temperature. Electronic nose (E-nose) analysis detected a total of 41 and 35 volatiles during the room and cold temperature storages, respectively. Clusters were discriminated according to storage types. These findings provide valuable data for broccoli flavor quality by different storage types.

The effects of dielectric barrier discharge cold plasma on the safety and shelf life parameters of mozzarella cheese

The current study aimed to evaluate the effect of dielectric barrier discharge cold atmospheric plasma (DBD-CAP) on mozzarella cheese during 9 days of storage at 4 °C. The effect of DBD-CAP at 75 kV at three different treatment times (1, 3, and 5 min) on enterohemorrhagic Escherichia coli (EHEC), microbiological, physical, rheological, and sensory characteristics was analyzed. Moreover, DBD-CAP effects on composition, physicochemical, texture, rheology, meltability, oiling-off, sensory, and shelf life were evaluated. Our results showed that DBD-CAP at 3 and 5 min treatment time removed EHEC while reducing the total microbiota, Pseudomonas, Enterobacteriaceae, mesophilic bacteria, and yeasts. Moreover, DBD-CAP maintained the treated mozzarella samples' moisture, fat content, pH, and protein content. However, 3 min mozzarella treatment maintained color, odor, and taste quality compared to the control due to reduced yeast growth. Shelf life evaluation revealed that 3 min DBD-CAP treatment extended the shelf life of mozzarella cheese by at least two days; therefore, DBD-CAP can be effectively used to extend the shelf life of mozzarella without apparent side effects.

Electronic tongue and nose sensor coupled with fluorescence spectroscopy to analyze aesthetic water quality parameters in drinking water distribution system

In this study, a new method is proposed for the evaluation of taste and odor of drinking water quality in water distribution systems by means of objective and quantitative indices derived from electronic sensors and fluorescence spectroscopy analysis. This method can be analyzed easily, quickly, and instead of subjective sensory analysis. Taste index (T.I.) and odor index (O.I.) were derived using an electronic tongue and nose. This method is simpler, faster, and less expensive than human panel methods. The tryptophan-like fluorescence index (TLF-I) and pipe deterioration index (PDI) of the water distribution system, derived from fluorescence spectroscopy, were also calculated to determine if the T.I. and O.I. were high or what was causing the difference. The target of comparison was the final water (point 1) that supplies water, and T.I., O.I., TLF-I, and PDI were calculated for the seven sampled points. Points 5 (3.91), 3 (3.82), and 6 (3.66) observed high T.I. O.I. was highest in the order of points 6 (3.65), 3 (3.16), and 5 (2.51). High TLF-I was observed at points 5 (160), 3 (111), and 6 (89), indexing a solid correlation. Other influencing factors at points 5, 3, and 6 included the PDI and water supply of the reservoir type. Point 5 had the highest PDI of 0.47. These results suggest that TLF-I and PDI can serve as indicators for interpreting the causes of changes in T.I. and O.I., which are indicators of aesthetic water quality. This method can assist in managing taste and odor quality data in drinking water distribution networks.

Improving nutritional and sensory properties of rice bran by germination and solid-state fermentation with fungi

Rice bran, a by-product of the rice milling industry, is rich in protein, fiber, and other nutrients. However, its utilization in food has been limited due to the presence of unpleasant flavors and anti-nutritional components. The present study investigated the impact of germination and solid-state fermentation with various fungi starters on the nutritional and sensory features of rice bran. The results showed germination can significantly decrease phytic acid content and increase the contents of protein and fibers but had a negligible influence on the sensory characteristics of rice bran. Fungal fermentation demonstrated a notable increase in protein content and effective degradation of insoluble fiber and phytic acid in rice bran. Meanwhile, the sensory characteristics of rice bran after fermentation with different fungal cultures varied according to the instrumental analysis (electronic nose/tongue and GC-IMS) and sensory panelists evaluations. Rice bran fermented with Aspergillus niger, Actinomucor elegans and liquor koji exhibited similar GC-IMS spectra and characteristics of odor. However, A. niger imparted bran a musty smell and A. elegans contributed tastes of bitter and astringency. Mucor racemosus fermentation resulted in the highest score of fruity odor. Additionally, rice bran fermented with soy sauce koji stood out with the highest richness score, distinguishing it from other fermented brans. This research can provide insights into improving nutritional and sensory attributes of rice bran.

Characterization of Key Odor-Active Compounds in Draft Beers for the Chinese Market Using Molecular Sensory Science Approaches.

Beer is a popular alcoholic beverage worldwide. However, limited research has been conducted on identifying key odor-active components in lager-type draft beers for the Chinese market. Therefore, this study aims to elucidate the odor characteristics of the four most popular draft beer brands through a sensory evaluation and an electronic nose. Subsequently, the four draft beers were analyzed through solid-phase microextraction and liquid-liquid extraction using a two-dimensional comprehensive gas chromatography-olfactometry-mass spectrometry analysis (GC×GC-O-MS). Fifty-five volatile odor compounds were detected through GC×GC-O-MS. Through an Aroma Extract Dilution Analysis, 22 key odor-active compounds with flavor dilution factors ≥ 16 were identified, with 11 compounds having odor activity values > one. An electronic nose analysis revealed significant disparities in the odor characteristics of the four samples, enabling their distinct identification. These findings help us to better understand the flavor characteristics of draft beer and the stylistic differences between different brands of products and provide a theoretical basis for objectively evaluating the quality differences between different brands of draft beer.

The impacts of cold plasma on the taste and odor formation of dried silver carp products

This study investigated non-thermal pretreatment (cold plasma, CP) on the flavor (taste and odor) profiles of dried fish products. CP treatment of 5 min contributed to accumulation of umami nucleotides adenosine 5′-monophosphate (AMP) from 30.96 to 40.82 μg/g and inosine 5′-monophosphate (IMP) from 2009.29 to 2132.23 μg/g, and significant reduction of bitter hypoxanthine ribonucleoside (HxR) and hypoxanthine (Hx), respectively (P < 0.05) in the dried fish products. A noticeable enhancement in sweet glycine (from 429.41 to 490.03 mg/100 g) and umami glutamic acid (from 55.68 to 67.76 mg/100 g) accompanied with the CP treatment (P < 0.05) based on taste activity value (TAV > 1). And the characteristic odor volatiles (nonanal, hexanal and 1-octen-3-ol) were strengthened 2.13-, 2.16- and 2.17- folds, respectively (P < 0.05). The results of equivalent umami concentration and Gibbs free energy calculation, combining with the correlation analysis, indicate that nucleotides and free amino acids synergically enhanced the taste improvement of dried fish products. Moderate lipids oxidation favored the formation of characteristic volatiles. The CP pretreatment offered new strategies for enhancing flavor of dried fish products.

Characterization of a Human Respiratory Mucosa Model to Study Odorant Metabolism.

Nasal xenobiotic metabolizing enzymes (XMEs) are important for the sense of smell because they influence odorant availability and quality. Since the major part of the human nasal cavity is lined by a respiratory mucosa, we hypothesized that this tissue contributed to nasal odorant metabolism through XME activity. Thus, we built human respiratory tissue models and characterized the XME profiles using single-cell RNA sequencing. We focused on the XMEs dicarbonyl and l-xylulose reductase, aldehyde dehydrogenase (ALDH) 1A1, and ALDH3A1, which play a role in food odorant metabolism. We demonstrated protein abundance and localization in the tissue models and showed the metabolic activity of the corresponding enzyme families by exposing the models to the odorants 3,4-hexandione and benzaldehyde. Using gas chromatography coupled with mass spectrometry, we observed, for example, a significantly higher formation of the corresponding metabolites 4-hydroxy-3-hexanone (39.03 ± 1.5%, p = 0.0022), benzyl alcohol (10.05 ± 0.88%, p = 0.0008), and benzoic acid (8.49 ± 0.57%, p = 0.0004) in odorant-treated tissue models compared to untreated controls (0 ± 0, 0.12 ± 0.12, and 0.18 ± 0.18%, respectively). This is the first study that reveals the XME profile of tissue-engineered human respiratory mucosa models and demonstrates their suitability to study nasal odorant metabolism.

Recall of Odorous Objects in Virtual Reality

The aim was to investigate how the congruence of odors and visual objects in virtual reality (VR) affects later memory recall of the objects. Participants (N = 30) interacted with 12 objects in VR. The interaction was varied by odor congruency (i.e., the odor matched the object’s visual appearance, the odor did not match the object’s visual appearance, or the object had no odor); odor quality (i.e., an authentic or a synthetic odor); and interaction type (i.e., participants could look and manipulate or could only look at objects). After interacting with the 12 objects, incidental memory performance was measured with a free recall task. In addition, the participants rated the pleasantness and arousal of the interaction with each object. The results showed that the participants remembered significantly more objects with congruent odors than objects with incongruent odors or odorless objects. Furthermore, interaction with congruent objects was rated significantly more pleasant and relaxed than interaction with incongruent objects. Odor quality and interaction type did not have significant effects on recall or emotional ratings. These results can be utilized in the development of multisensory VR applications.

Physicochemical parameters combined flash GC e-nose and NIR for quality and volatile characterization of Zhenjiang vinegar with different aging time

In order to clarify the scientific connotation of the processing adjuvant vinegar of “the aging the better”, the physicochemical indexes, antioxidant activity in vitro, odor characteristics and NIR spectrum characteristics of Zhenjiang vinegar with different aging time were comprehensively studied, and the compositional characterization by UPLC-MS. The results showed that the physicochemical quality of Zhenjiang vinegar increased rapidly during the 2–3 years, entered a rising stable period during the 5–8 years and entered a sudden increase period during the 8–10 years of fermentation. Overall, it was in line with the trend that “the aging the better”. The study further characterized the odor changes of different aging time samples, established a fast and non-damage SVM discriminant model based on NIR spectral characteristics (accuracy 100 %), and 753 components were characterized by UPLC-MS, in order to provide a reference for the quality evaluation and standard improvement of Zhenjiang vinegar and processing adjuvant.

Tea Quality of the Mysterious "Dahongpao Mother Tree" (Camellia sinensis).

The quality of the Dahongpao mother tree (Camellia sinensis) remains a mystery to this day. In this study, for the first time, the differences between the Dahongpao mother tree (MD) and Dahongpao cuttings (PD), in terms of odor characteristics and taste characteristics were analyzed by metabomics. The results showed that MD had stronger floral, fruity, green, and woody odor characteristics than PD, and that the contributions were mainly from dihydromyrcenol, methyl salicylate, 2-isobutylpyrazine, 1,6-dihydrocarveol, gamma-terpineol, and linalyl acetate. Further, fresh and brisk taste and mellowness taste characteristics of MD were significantly higher than PD, with contributions mainly from amino acids and derivatives and organic acids. Secondly, bitterness taste characteristics of PD were significantly higher than MD, with contributions from phenolic acids, flavones, and flavonols. This study preliminarily unraveled the legend of the superior quality of the Dahongpao mother tree, and also provided an important reference for the breeding of tea-tree cuttings.

Investigation of odor pollution by utilizing selected ion flow tube mass spectrometry (SIFT-MS) and principal component analysis (PCA).

Odor pollution, also referred to as odor nuisance, is a growing environmental concern that is significantly associated with mental health. Once emitted into the air, the concentration of odorous substances varies considerably with wind conditions, leading to difficulties in timely sampling. In the present study, we employed selected ion flow tube mass spectrometry (SIFT-MS) to measure 22 odor-producing molecules continuously in an urban-rural complex city. In addition, we applied statistical analyses, principal component analysis (PCA), and a conditional probability function (CPF) to the datasets obtained from SIFT-MS to identify the odor characteristics at two study sites. At site A, odorants related to livestock farming and industry showed high factor loadings on principal components (PCs) from the PCA. In contrast, we estimated that the odorous gaseous chemicals affecting site B were closely related to sewage treatment and municipal solid waste disposal. Similar CPF patterns of grouped substances from the PCA supported the association between potential odor sources and specific odorants at site B, which helped estimate possible source locations. Consequently, our findings indicate that continuous monitoring of odorous substances using SIFT-MS can be an effective way to provide sufficient information on odor-producing molecules, leading to the clear identification of odor characteristics despite the high variability of odorous substances.

A deep learning-based quantitative prediction model for the processing potentials of soybeans as soymilk raw materials

Current technologies as correlation analysis, regression analysis and classification model, exhibited various limitations in the evaluation of soybean possessing potentials, including single, vague evaluation and failure of quantitative prediction, and thereby hindering more efficient and profitable soymilk industry. To solve this problem, 54 soybean cultivars and their corresponding soymilks were subjected to chemical, textural, and sensory analyses to obtain the soybean physicochemical nature (PN) and the soymilk profit and quality attribute (PQA) datasets. A deep-learning based model was established to quantitatively predict PQA data using PN data. Through 45 rounds of training with the stochastic gradient descent optimization, 9 remaining pairs of PN and PQA data were used for model validation. Results suggested that the overall prediction performance of the model showed significant improvements through iterative training, and the trained model eventually reached satisfying predictions (|relative error| ≤ 20%, standard deviation of relative error ≤ 40%) on 78% key soymilk PQAs. Future model training using big data may facilitate better prediction on soymilk odor qualities.

Tailoring hole density and nitriding in graphene membranes for enhanced gas separation and selectivity

Sour gas, containing acidic gases like hydrogen sulfide and carbon dioxide, has a characteristic odor, and toxic effects, and reduces the overall energy content of the gas. Moreover, the presence of these acid gases in water leads to the formation of highly corrosive acid compounds, increasing transportation costs. Membrane technology is widely used for gas separation due to its low energy consumption, ability to operate at ambient temperatures, lightweight and compact equipment, ease of access to all separated phases, and high process flexibility. Computer simulation bridges the gap between microscopic temporal and spatial scales and the macroscopic laboratory environment. Molecular dynamics is a technique for analyzing the physical motion of atoms and molecules. By simulating the interactions between atoms and molecules over time, insights into the dynamic evolution of the system can be obtained. This research investigates the CO2/CH4 separation performance of modified graphene membranes (C3N) using molecular dynamics simulations under various operating conditions. First, cavities with different geometrical shapes and edge atoms were created, and gas separation was examined at 300 K. A cavity with a diameter of 4.9 Å exhibited the highest selectivity (infinity) and a carbon dioxide flux of 365.65 mol/m2·s, while methane molecules were completely blocked. This cavity was selected as the optimal structure. Next, the effects of pressure, and hole density on gas separation were studied. The results showed that the flux is directly proportional to the feed pressure, reaching 503.7845 mol/m2·s at a pressure of 328.0424 atm while maintaining infinite selectivity. Finally, examining the impact of cavity density on the separation process revealed that drilling four holes in the membrane area was the optimal density, achieving infinite selectivity, zero methane flux, and a carbon dioxide flux of 292.601 mol/m2·s.

COMPARISON ANTIOXIDAN ACTIVITY OF RED GINGER (Zingiber officinale var. rubrum) ETANOL EXTRACTION BY MASERATION AND DIGESTI MASERATION METHODS

The red ginger plant (Zingiber officinale variety rubrum) is a common plant in our surroundings that is used to cure a number of degenerative diseases as well as pain management, antipyretic, and anti-inflammatory conditions. Volatile oil, non-volatile oil and starch substances are part of red ginger. The volatile oil or volatile oil gives ginger its characteristic odor, and the non-volatile oil or oleoresin gives it its bitter taste. Oleoresin, which consists of resin, gingerol, and shogaol, It is an antioxidant needed by the body to prevent free radicals from forming and being harmful to the body. The reason for this is to determine the antioxidant content of red ginger. The extraction methods used were maceration with the process of soaking the material using nonpolar solvents without heating and digestion maceration or kinetic maceration (continuous stirring) using weak heating at 40-50°C. Very strong antioxidant activity was obtained where digestion maceration with an IC50 value of 7,30 was stronger than maceration with an IC50 of 11,90 because heating in digestion maceration opens the tissue in red ginger so that active compounds are extracted out.

FORMULASI DAN EVALUASI SEDIAAN SERUM WAJAH EKSTRAK ETANOL KOMBINASI DARI EKSTRAK KULIT JERUK NIPIS (Citrus aurantiifolia) DAN EKSTRAK KULIT BUAH NAGA MERAH (Hylocereus polyrhizus)

Background: The skin of the key orange (Citrus aurantiifolia) contains kuersetin, miristin, routinely, tangerine, naringin and hesperine, while the skin of the red dragon fruit (Hylocereus polyrhizus) contains betaalanin, anthocyanin, vitamin a, vitamin a, vitamin e, turnioid, flavonoid, tiamin, niacin, piridoine, kobalamin, carotene, and fitoalbumin. The research was intended to formulate it in a availability of facial serum and then evaluate its quality formula for a better facial serum from 16-4954-1998. Methods : This method of research is experimental in the laboratory by making 4 formulas consisting of F1 as serum bases, F2 ratio EKJN and EKBNM (1:1), F3 ratio EKJN and EKBNM (1:2) ,F4 ratio EKJN and EKBNM (2:1).Results : The results of all the formulas for existing existing face-serum EKJN ethanol and EKBNM viscers show a clear, clear, yellowish color, a gel-based, characteristic and homogenous odor. pH and viscosity scores on each condensed formula. No irritation test on the formula showed irritation to the skin.Conclusion : Based on this, it can be concluded that the combined ethanol extract of lime peel extract and red dragon fruit peel extract can be formulated into a facial serum cosmetic preparation and meets the quality requirements according to SNI.

Influences of human milk proteins on the release of human milk odors: Non-covalent interactions between α-lactalbumin and key odor skeleton compounds

Human milk (HM) provides optimal nutrition for infants, but infant formula (IF) serves as a potential alternative to HM when breastfeeding is not an option. However, IF possesses a more intense aroma than HM, and it is often challenging to reduce this disparity due to its stringent production regulations. Therefore, investigating the interaction between HM proteins and odor molecules is essential for comprehending the distinct odor characteristics of HM and guiding improvements in IF to mimic the aroma of HM. This research aims to characterize the HM odor and explore the influence of HM α-lactalbumin (HMLB) on the release of HM odor skeleton compounds (OSC) using a combination of computer simulation, human perceptions, and instrumental analyses. A total of 20 OSCs were identified. Notably, the release of most of these compounds was negatively correlated with the HM protein content, with the strongest negative correlations being observed for hexanal, nonanal, and decanal (|R| ≥ 0.7, P < 0.01). The molecular docking simulations demonstrated that HMLB inhibited the volatilization of hexanal, nonanal, and decanal, thereby increasing the odor threshold of these odor compounds (61.94 %, 241.5 %, and 198.6 %). This inhibition was mainly achieved through the formation of hydrogen bonding and hydrophobic interactions, a finding corroborated by multi-spectroscopic analysis. Overall, the experimental results provide valuable insights into the odor mechanism of HM and contribute to the development of IF that mimics the HM odor.

Effect of processing methods on physicochemical and cup quality of coffee at Jimma, Ethiopia

Coffee quality is a complex attribute influenced by a variety of factors, including postharvest processing methods. The goal of this study was to investigate the impact of coffee processing methods on coffee quality (raw, cup, and biochemical makeup) in Jimma, which represents the midland areas. Coffee samples were collected for Jimma agricultural research center and processed with three methods (washed, Semi-washed and dry process). The result indicated that washed coffee beans scored significantly the highest color (13.43) and odor [10] score than the other processing methods. The statistically best raw quality score (35.57 %) was therefore reported for washed coffee in Jimma. Cup quality attributes however were not significantly affected by processing methods. Among chemical composition studied, lipid was significantly affected by processing methods and highest lipid 13.74 and 13.17 g/100g was reported for semi-washed and washed coffee beans respectively. Generally, washed and semi-washed coffee were preferable in terms of bean color and odor quality. Correlations were found among cup quality attributes and chemical compositions. However, further research into the accessibility and economics of coffee processing methods in the area is necessary.

60Co γ‐radiation at low‐dose level alters volatile compounds of blueberry during storage

Summary60Co γ‐radiation was applied to blueberry fruits in an effort to investigate a safe, eco‐friendly and effective blueberry preservation technique. However, the preservation effects were variable depending on tissue tolerance to irradiation doses. Moreover, irradiation may cause off‐odour. In this study, we examined the effects of three low doses of 60Co γ‐radiation on the physical and flavour attributes of blueberry. The results showed that 60Co γ‐radiation did not significantly improve fruit quality but extend the shelf life up to 15 days at 25 °C and 30 days at 4 °C. Compared with the control group, the preservation effect of 0.5–1.0 kGy irradiation treatment on blueberry fruit was not obvious before 15 days but maintained 65% of fruit firmness and reduced the loss of nutrients afterwards at 4 °C. At 25 °C, irradiation treatment caused up to a 150% increase in polyphenol oxidase activity, which was relevant to colour changes in late storage. Headspace Gas Chromatography Ion Mobility Spectrometry (HS‐GC‐IMS) was applied, and 33 volatile organic compounds (VOCs) in blueberry treated with different radiation doses were identified, including 11 esters, 8 aldehydes, 7 alcohols, 6 ketones and other substances, which increased with increasing radiation dose. Radiation reduced the green taste of blueberry and promoted their ripening. Radiation above the level of 1.02 kGy led to the flavour deterioration of blueberry such as ethyl trans‐2‐butenoate. The side effects of radiation on the aroma of blueberry could be offset by low‐temperature storage. Blueberry stored at 4 °C contained more aldehydes with a heavier fresh/green aroma. Six aromas were proposed to be characteristic odour markers of radiated blueberry.