The effect of mango aroma in low-sugar beverage: A sensory study on odor induced sweetness enhancement.

Excessive intake of sugar has become a public concern. However, it is challenging for food industries to decrease sugar level without sacrificing safety and sensory profile. Odor-induced sweetness enhancement (OISE) is believed to be a novel and promising strategy for sugar reduction. In order to investigate the OISE effect of mango aroma and evaluate its degree of sugar reduction in low-sugar beverages, a mathematical model was constructed through sensory evaluation in this study. The results showed that the maximum liking of low-sugar model beverages was 4.28 % sucrose and 0.57 % mango flavor. The most synergistic of OISE was at the concentration level of 2.24 % sucrose + 0.25 % mango flavor, which was equivalent to 2.96 % pure sucrose solution. With 32.14 % sugar reduction, the mango aroma was suggested to generate the OISE effect. However, the same level of garlic aroma was not able to enhance sweetness perception, suggesting that the congruency of aroma and taste is a prerequisite for the OISE effect to occur. This study demonstrated that the cross-modal interaction of mango aroma on sweetness enhancement in low-sugar model beverages could provide practical guidance for developing sugar-reduced beverages without applying sweeteners.

Addressing flavor challenges in reduced-fat dairy products: A review from the perspective of flavor compounds and their improvement strategies.

In recent years, the demand for reduced-fat dairy products (RFDPs) has increased rapidly as the health risks associated with high-fat diets have become increasingly apparent. Unfortunately, lowering the fat content in dairy products would reduce the flavor perception of fat. Fat-derived flavor compounds are the main contributor to appealing flavor among dairy products. However, the contribution of fat-derived flavor compounds remains underappreciated among the flavor improvement factors of RFDPs. Therefore, this review aims to summarize the flavor perception mechanism of fat and the profile of fat-derived flavor compounds in dairy products. Furthermore, the characteristics and influencing factors of flavor compound release are discussed. Based on the role of these flavor compounds, this review analyzed the current and potential flavor improvement strategies for RFDPs, including physical processing, lipolysis, microbial applications, and fat replacement. Overall, promoting the synthesis of milk fat characteristic flavor compounds in RFDPs and aligning the release properties of flavor compounds from the RFDPs with those of equivalent full-fat dairy products are two core strategies to improve the flavor of reduced-fat dairy products. In the future, better modulation of the behavior of flavor compounds by various methods is promising to replicate the flavor properties of fat in RFDPs and meet consumer sensory demands.

Metagenomic and flavoromic profiling reveals the correlation between the microorganisms and volatile flavor compounds in Monascus-fermented cheese.

The Monascus-fermented cheese (MC) is a unique cheese product that undergoes multi-strain fermentation, imparting it with distinct flavor qualities. To clarify the role of microorganisms in the formation of flavor in MC, this study employed SPME (arrow)-GC-MS, GC-O integrated with PLS-DA to investigate variations in cheese flavors represented by volatile flavor compounds across 90-day ripening periods. Metagenomic datasets were utilized to identify taxonomic and functional changes in the microorganisms. The results showed a total of 26 characteristic flavor compounds in MC at different ripening periods (VIP＞1, p < 0.05), including butanoic acid, hexanoic acid, butanoic acid ethyl ester, hexanoic acid butyl ester, 2-heptanone and 2-octanone. According to NR database annotation, the genera Monascus, Lactococcus, Aspergillus, Lactiplantibacillus, Staphylococcus, Flavobacterium, Bacillus, Clostridium, Meyerozyma, and Enterobacter were closely associated with flavor formation in MC. Ester compounds were linked to Monascus, Meyerozyma, Staphylococcus, Lactiplantibacillus, and Bacillus. Acid compounds were linked to Lactococcus, Lactobacillus, Staphylococcus, and Bacillus. The production of methyl ketones was closely related to the genera Monascus, Staphylococcus, Lactiplantibacillus, Lactococcus, Bacillus, and Flavobacterium. This study offers insights into the microorganisms of MC and its contribution to flavor development, thereby enriching our understanding of this fascinating dairy product.

Revealing microbiota characteristics and predicting flavor-producing sub-communities in Nongxiangxing baijiu pit mud through metagenomic analysis and metabolic modeling.

The microorganisms of the pit mud (PM) of Nongxiangxing baijiu (NXXB) have an important role in the synthesis of flavor substances, and they determine attributes and quality of baijiu. Herein, we utilize metagenomics and genome-scale metabolic models (GSMMs) to investigate the microbial composition, metabolic functions in PM microbiota, as well as to identify microorganisms and communities linked to flavor compounds. Metagenomic data revealed that the most prevalent assembly of bacteria and archaea was Proteiniphilum, Caproicibacterium, Petrimonas, Lactobacillus, Clostridium, Aminobacterium, Syntrophomonas, Methanobacterium, Methanoculleus, and Methanosarcina. The important enzymes ofPMwere in bothGH and GT familymetabolism. A total of 38 high-quality metagenome-assembled genomes (MAGs) were obtained, including those at the family level (n = 13), genus level (n = 17), and species level (n = 8). GSMMs of the 38 MAGs were then constructed. From the GSMMs, individual and community capabilities respectively were predicted to be able to produce 111 metabolites and 598 metabolites. Twenty-three predicted metabolites were consistent with the metabonomics detected flavors and served as targets. Twelve sub-community of were screened by cross-feeding of 38 GSMMs. Of them, Methanobacterium, Sphaerochaeta, Muricomes intestini, Methanobacteriaceae, Synergistaceae, and Caloramator were core microorganisms for targets in each sub-community. Overall, this study of metagenomic and target-community screening could help our understanding of the metabolite-microbiome association and further bioregulation of baijiu.

Quality and Flavor Difference in Dry-Cured Meat Treated with Low-Sodium Salts: An Emphasis on Magnesium.

The present study aimed to develop low-sodium curing agents for dry-cured meat products. Four low-sodium formulations (SPMA, SPM, SP, and SM) were used for dry-curing meat. The physicochemical properties and flavor of the dry-cured meat were investigated. The presence of Mg2+ ions hindered the penetration of Na+ into the meat. The weight loss, moisture content, and pH of all low-sodium salt groups were lower than those of S. Mg2+ addition increased the water activity (Aw) of SPMA, SPM, and SM. Dry-curing meat with low-sodium salts promoted the production of volatile flavor compounds, with Mg2+ playing a more prominent role. Furthermore, low-sodium salts also promoted protein degradation and increased the content of free amino acids in dry-cured meat, especially in SM. Principal component analysis (PCA) showed that the low-sodium salts containing Mg2+ were conducive to improving the quality of dry-cured meat products. Therefore, low-sodium salts enriched with Mg2+ become a desirable low-sodium curing agent for achieving salt reduction in dry-cured meat products.

Forecasting vaping health risks through neural network model prediction of flavour pyrolysis reactions.

Vaping involves the heating of chemical solutions (e-liquids) to high temperatures prior to lung inhalation. A risk exists that these chemicals undergo thermal decomposition to new chemical entities, the composition and health implications of which are largely unknown. To address this concern, a graph-convolutional neural network (NN) model was used to predict pyrolysis reactivity of 180 e-liquid chemical flavours. The output of this supervised machine learning approach was a dataset of probability ranked pyrolysis transformations and their associated 7307 products. To refine this dataset, the molecular weight of each NN predicted product was automatically correlated with experimental mass spectrometry (MS) fragmentation data for each flavour chemical. This blending of deep learning methods with experimental MS data identified 1169 molecular weight matches that prioritized these compounds for further analysis. The average number of discrete matches per flavour between NN predictions and MS fragmentation was 6.4 with 92.8% of flavours having at least one match. Globally harmonized system classifications for NN/MS matches were extracted from PubChem, revealing that 127 acute toxic, 153 health hazard and 225 irritant classifications were predicted. This approach may reveal the longer-term health risks of vaping in advance of clinical diseases emerging in the general population.

Community Engagement, Jurisdictional Experience, and Previous Tobacco-Related Ordinances in Neighboring Communities as Drivers of Flavored Tobacco Bans in Los Angeles County.

We examined whether a community engagement approach and jurisdictional attributes were associated with local action to restrict the sale of flavored tobacco products in Los Angeles County during 2019-2022. We estimated crude and adjusted risk ratios to examine these associations. Jurisdictions that used an active community engagement approach to adopt a flavored tobacco ban ordinance, those with previous experience adopting other tobacco-related ordinances, and those located next to communities that have an existing tobacco retail license ordinance were more likely than jurisdictions without these attributes to adopt a new ordinance to restrict the sale of flavored tobacco products. Efforts to adopt such an ordinance were generally more successful in jurisdictions where community members were engaged and policy makers were familiar with the adoption of public health ordinances.

Investigations on the Diffusion Behavior of Smoke-Associated Aroma Compounds into the Sausage Matrix as Affected by Casing, Caliber, and Packaging.

The aim of the study was to investigate how smoke-associated flavoring substances behave during storage in Frankfurter-type sausages. The diffusion behavior of seven selected aroma substances in the sausage matrix and the influence of the packaging and the casing were examined over a storage period of 28 days. The sausages were cut into uniformly thick layers at defined time intervals and examined by headspace-solid phase microextraction-gas chromatography-mass spectrometry. In general, three different groups could be distinguished: (1) even distribution over the entire product on the first day after smoking; (2) clear concentration gradient from outside to inside on the first day of storage, which leveled out until day 28 of storage; and (3) a clear concentration gradient that remained present throughout the storage period. In addition, only small effects were found in the distribution of flavorings between two types of packaging, selected casing, or different calibers.

Oral soluble shell prepared from OSA starch incorporated with tea polyphenols for the microencapsulation of Sichuan pepper oleoresin: Characterization, flavor stability, release mechanisms and its application in mooncake.

The market share of Sichuan pepper oleoresin (SPO) in the flavor industry is increasing steadily; however, its high volatility, low water solubility, and poor stability continue to pose significant challenges to application. The microencapsulation prepared by emulsion embedding and spray drying is considered as an effective technique to solve the above problems. Sodium octenyl succinate starch (OSA starch) and tea polyphenols (TPs) were used to develop OSA-TPs complex as encapsulants for SPO to prepare orally soluble microcapsules. And the optimum doping of TPs was determined. SPO microcapsules have good properties with high encapsulation efficiency up to 88.13 ± 1.48% and high payload up to 41.58 ± 1.86% with low water content and high heat resistance. The binding mechanism of OSA starch with TPs and its regulation mechanism and effect on SPOs were further analyzed and clarified. The binding mechanism between OSA starch and TPs was clarified in further analyses. The OSA-TPs complexes enhanced the rehydration, release in food matrix and storage stability of SPO, and exhibited good sensory immediacy. Flavor-improved mooncakes were successfully developed, achieving the combination of mooncake flavor and SPO flavor. This study provided a valuable way to prepare flavoring microcapsules suitable for the catering industry, opened up the combined application of SPO and bakery ingredients, and was of great practical value and significance for improving the processing quality of flavor foods, driving the development of the SPO industry, and enhancing the national dietary experience.

High­oxygen-modified atmospheric packaging delays flavor and quality deterioration in fresh-cut broccoli.

The purpose of this study was to investigate the impact of high­oxygen-modified atmospheric packaging (HOMAP) on aroma changes in fresh-cut broccoli during storage and to explore its regulatory mechanisms. The results showed that HOMAP reduced the levels of undesirable aroma substances hexanoic acid, isobutyric acid, cyclopentanone and increased glucosinolate accumulation by inhibiting the expression of arogenate/prephenate dehydratase (ADT), bifunctional aspartate aminotransferase and glutamate/aspartate-prephenate aminotransferase (PAT), thiosulfate/3-mercaptopyruvate Transferase (TST) to reduce the odor of fresh-cut broccoli. HOMAP inhibited the expression of respiratory metabolism related genes 6-phosphate fructokinase 1 (PFK), pyruvate kinase (PK), and NADH-ubiquinone oxidoreductase chain 6 (ND6). In HOMAP group, the low expression of phospholipase C (PLC), phospholipase A1 (PLA1), linoleate 9S-lipoxygenase 1 (LOX1) related to lipid metabolism and the high expression of naringenin 3-dioxygenase (F3H), trans-4-Hydroxycinnamate (C4H), glutaredoxin 3 (GRX3), and thioredoxin 1 (TrX1) in the antioxidant system maintained membrane stability while reducing the occurrence of membrane lipid peroxidation.

Characterization of Key Aroma Compounds and Main Contributing Amino Acids in Hot-Pressed Oil Prepared from Various Peanut Varieties.

The production of peanut oil in the industrial sector necessitates the utilization of diverse raw materials to generate consistent batches with stable flavor profiles, thereby leading to an increased focus on understanding the correlation between raw materials and flavor characteristics. In this study, sensory evaluations, headspace solid-phase micro-extraction gas chromatography mass spectrometry (HS-SPME-GC-MS), odor activity value (OAV) calculations, and correlation analysis were employed to investigate the flavors and main contributing amino acids of hot-pressed oils derived from different peanut varieties. The results confirmed that the levels of alcohols, aldehydes, and heterocyclic compounds in peanut oil varied among nine different peanut varieties under identical processing conditions. The OAVs of 25 key aroma compounds, such as methylthiol, 3-ethyl-2,5-dimethylpyrazine, and 2,3-glutarone, exceeded a value of 1. The sensory evaluations and flavor content analysis demonstrated that pyrazines significantly influenced the flavor profile of the peanut oil. The concentrations of 11 amino acids showed a strong correlation with the levels of pyrazines. Notably, phenylalanine, lysine, glutamic acid, arginine, and isoleucine demonstrated significant associations with both pyrazine and nut flavors. These findings will provide valuable insights for enhancing the sensory attributes of peanut oil and selecting optimal raw peanuts for its production.

Formation of Volatile Pyrazinones in the Asparagine Maillard Reaction Systems and Novel Pyrazinone Formation Pathways in the Amidated-Alanine Maillard Reaction Systems.

Maillard reaction (MR) plays a pivotal role in the food flavor industry, including a cascade of reactions starting with the reaction between amino compounds and reducing sugars, and thus provides various colors and flavors. A new group of volatile compounds called pyrazinones found in MR are now getting more attention. In this study, eight volatile pyrazinones were found in the asparagine MR systems, in which 3,5-dimethyl- and 3,6-dimethyl-2(1H)-pyrazinones were reported for the first time. The major formation pathways were the reactions between asparagine and α-dicarbonyls, with decarboxylation as a critical step. Besides, novel alternative pathways involving alanine amidation and successive reactions with α-dicarbonyls were explored and successfully formed eight pyrazinones. The major differences between alanine-amidated pathways and decarboxylation pathways are the amidation step and absence of the decarboxylation step. For the alanine-amidated pathways, the higher the temperature, the better the amidation effect. The optimal amidation temperature was 200 °C in this study. The reaction between the alanine amide and α-dicarbonyls after amidation can happen at low temperatures, such as 35 and 50 °C, proposing the possibility of pyrazinone formation in real food systems. Further investigations should be conducted to investigate volatile pyrazinones in various food systems as well as the biological effects and kinetic formation differences of the volatile pyrazinones.

Novel Catechol O-methyltransferases from Lentinula edodes Catalyze the Generation of Taste-Active Flavonoids.

Due to the increasing demand for natural food ingredients, including taste-active compounds, enzyme-catalyzed conversions of natural substrates, such as flavonoids, are promising tools to align with the principles of Green Chemistry. In this study, a novel O-methyltransferase activity was identified in the mycelium of Lentinula edodes, which was successfully applied to generate the taste-active flavonoids hesperetin, hesperetin dihydrochalcone, homoeriodictyol, and homoeriodictyol dihydrochalcone. Furthermore, the mycelium-mediated OMT activity allowed for the conversion of various catecholic substrates, yielding their respective (iso-)vanilloids, while monohydroxylated compounds were not converted. By means of a bottom-up proteomics approach, three putative O-methyltransferases were identified, and subsequently, synthetic, codon-optimized genes were heterologously expressed in Escherichia coli. The purified enzymes confirmed the biocatalytic O-methylation activity against targeted flavonoids containing catechol motifs.

Core microbes identification and synthetic microbiota construction for the production of Xiaoqu light-aroma Baijiu.

Baijiu production has relied on natural inoculated Qu as a starter culture, causing the unstable microbiota of fermentation grains, which resulted in inconsistent product quality across batches. Therefore, revealing the core microbes and constructing a synthetic microbiota during the fermentation process was extremely important for stabilizing product quality. In this study, the succession of the microbial community was analyzed by high-throughput sequencing technology, and ten core microbes of Xiaoqu light-aroma Baijiu were obtained by mathematical statistics, including Acetobacter, Bacillus, Lactobacillus, Weissella, Pichia,Rhizopus, Wickerhamomyces, Issatchenkia, Saccharomyces, and Kazachstania. Model verification showed that the core microbiota significantly affected the composition of non-core microbiota (P < 0.01) and key flavor-producing enzymes (R > 0.8, P < 0.01), thus significantly affecting the flavor of base Baijiu. Simulated fermentation validated that the core microbiota can reproduce the fermentation process and quality of Xiaoqu light-aroma Baijiu. The succession of bacteria was mainly regulated by acidity and ethanol, while the fungi, especially non-Saccharomyces cerevisiae, were mainly regulated by the initial dominant bacteria (Acetobacter, Bacillus, and Weissella). This study will play an important role in the transformation of Xiaoqu light-aroma Baijiu fermentation from natural fermentation to controlled fermentation and the identification of core microbes in other fermented foods.

Bitter flavors and bitter compounds in foods: identification, perception, and reduction techniques.

Bitterness is one of the five basic tastes generally considered undesirable. The widespread presence of bitter compounds can negatively affect the palatability of foods. The classification and sensory evaluation of bitter compounds have been the focus in recent research. However, the rigorous identification of bitter tastes and further studies to effectively mask or remove them have not been thoroughly evaluated. The present paper focuses on identification of bitter compounds in foods, structural-based activation of bitter receptors, and strategies to reduce bitter compounds in foods. It also discusses the roles of metabolomics and virtual screening analysis in bitter taste. The identification of bitter compounds has seen greater success through metabolomics with multivariate statistical analysis compared to conventional chromatography, HPLC, LC-MS, and NMR techniques. However, to avoid false positives, sensory recognition should be combined. Bitter perception involves the structural activation of bitter taste receptors (TAS2Rs). Only 25 human TAS2Rs have been identified as responsible for recognizing numerous bitter compounds, showcasing their high structural diversity to bitter agonists. Thus, reducing bitterness can be achieved through several methods. Traditionally, the removal or degradation of bitter substances has been used for debittering, while the masking of bitterness presents a new effective approach to improving food flavor. Future research in food bitterness should focus on identifying unknown bitter compounds in food, elucidating the mechanisms of activation of different receptors, and developing debittering techniques based on the entire food matrix.

Exploring the opinions and potential impact of unflavoured e-liquid on smoking cessation among people who smoke and smoking relapse among people who previously smoked and now use e-cigarettes: findings from a UK-based mixed methods study.

BACKGROUND: Although electronic cigarettes (e-cigarettes) appear to be effective in helping people who smoke to stop smoking, concerns about use of e-cigarettes among young people have led to restrictions on non-tobacco flavoured e-liquids in some countries and some US states. These restrictions could reduce the appeal of these products to non-smoking youth but could have negative consequences for people who smoke or use e-cigarettes. METHODS: In this mixed methods study, we recruited UK adults who smoked or used to smoke and subsequently vaped to explore their opinions of unflavoured e-liquids and their beliefs about how they would be impacted by hypothetical e-liquid flavour restrictions. Participants trialled an unflavoured e-liquid instead of their usual nicotine product for four hours and completed a survey and an online interview. RESULTS: Using Interpretive Phenomenological Analysis and graphically presented data, we found differences in participants' opinions of unflavoured e-liquid. If only unflavoured, tobacco flavoured, and menthol flavoured e-liquids remained on the UK market, some people who smoke or vape may be unaffected, but some may relapse to smoking or continue smoking. Despite most wanting to prevent young people from initiating vaping, participants had varying opinions on whether flavour restrictions would be an effective method. CONCLUSIONS: The findings highlight that people who smoke and vape could be impacted by flavour restrictions in a range of ways, some of which could have a potential adverse impact on harm reduction efforts in the UK (e.g., by making smoking more appealing than vaping).

Influence of Milk Pasteurization on the Key Aroma Compounds in a 30 Weeks Ripened Pilot-Scale Gouda Cheese Elucidated by the Sensomics Approach.

Gouda cheese was produced from pasteurized milk and ripened for 30 weeks (PM-G). By application of gas chromatography/olfactometry and an aroma extract dilution analysis on the volatiles isolated by extraction/SAFE distillation, 25 odor-active compounds in the flavor dilution (FD) factor range from 16 to 4096 were identified. Butanoic acid, 2- and 3-methylbutanoic acid, and acetic acid showed the highest FD factors, and 2-phenylethanol, δ-decalactone, and δ-dodecalactone were most odor-active in the neutral-basic fraction. Quantitations by stable isotope dilution assays followed by a calculation of odor activity values (OAVs) revealed acetic acid, 3-methylbutanoic acid, butanoic acid, and butane-2,3-dione with the highest OAVs. Finally, an aroma recombinate prepared based on the quantitative data well agreed with the aroma profile of the PM-G. In Gouda cheese produced from raw (nonpasteurized) milk (RM-G), qualitatively the same set of odor-active compounds was identified. However, higher OAVs of butanoic acid, hexanoic acid, and their corresponding ethyl esters were found. On the other hand, in the PM-G, higher OAVs for 3-methylbutanoic acid, 3-methylbutanol, 3-methylbutanal, and butane-2,3-dione were determined. The different rankings of these key aroma compounds clearly reflect the aroma differences of the two Gouda-type cheeses. A higher activity of lipase in the RM-G and higher amounts of free l-leucine in PM-G on the other side were responsible for the differences in the concentrations of some key aroma compounds.

Revealing core functional microorganisms in the fermentation process of Qicaipaojiao (Capsicum annuum L.) based on microbial metabolic network.

Paojiao, a typical Chinese traditional fermented pepper, is favored by consumers for its unique flavor profile. Microorganisms, organic acids, amino acids, and volatile compounds are the primary constituents influencing the development of paojiao's flavor. To elucidate the key flavor compounds and core microorganisms of Qicaipaojiao (QCJ), this study conducted a comprehensive analysis of the changes in taste substances (organic acids and amino acids) and volatile flavor compounds during QCJ fermentation. Key flavor substances in QCJ were identified using threshold aroma value and odor activity value and the core microorganisms of QCJ were determined based on the correlation between dominant microorganisms and the key flavor substances. During QCJ fermentation, 16 key taste substances (12 free amino acids and 4 organic acids) and 12 key aroma substances were identified. The fermentation process involved 10 bacteria and 7 fungal genera, including Lactiplantibacillus, Leuconostoc, Klebsiella, Pichia, Wickerhamomyces, and Candida. Correlation analysis revealed that the core functional microorganisms encompassed representatives from 8 genera, including 5 bacterial genera (Lactiplantibacillus, Weissella, Leuconostoc, Klebsiella, and Kluyvera) and 3 fungal genera (Rhodotorula, Phallus, and Pichia). These core functional microorganisms exhibited significant correlations with approximately 70 % of the key flavor substances (P < 0.05). This study contributes to an enhanced understanding of flavor formation mechanisms and offers valuable insight into flavor quality control in food fermentation processes.

Differential accumulation patterns of flavor compounds in Longjing 43 and Qunti fresh leaves and during processing responding to altitude changes.

Variations in cultivars and cultivation altitudes have significant impacts on tea flavour compounds however lack of comprehensive understanding. This study provided insights into differential accumulation of crucial flavour compounds in response to cultivars, cultivation altitudes, and processing. Twelve flavonoids (262.4 âˆ¼ 275.4 mg•g-1) and 20 amino acids (AAs) (56.5 âˆ¼ 64.8 mg•g-1) were comparative analyzed in 'Longjing 43' and 'Qunti' fresh leaves harvested at low (80 m, LA) and high (500 m, HA) altitudes. Additionally, an in-depth correlation unravelling of 31 alkaloids, 25 fatty acids, 31 saccharides, 8 organic acids, and 7 vitamins and flavonoids/AAs during green tea (GT) and black tea (BT) processing was performed. Enhenced flavonoid accumulation alongside higher AAs and saccharides in HA GT promoted a sweet/mellow flavour. Abundant flavonoids, AAs, and saccharides derivates in LA BT gave rise to a sweet aftertaste. The study presents an integrated illustration of major flavour compounds' differential accumulation patterns and their interrelations, providing new insights into the influence of cultivation conditions on tea flavour.