Analyzing the Effect of Baking on the Flavor of Defatted Tiger Nut Flour by E-Tongue, E-Nose and HS-SPME-GC-MS

Advancing Butter Cookie Quality: Low-Oxygen Baking as a Dual Approach for Sensory Enhancement and Acrylamide Mitigation

This study investigated the impact of oxygen concentrations during baking on flavor, sensory perception, and acrylamide content in butter cookies. Cookies were baked at 190 and 210 °C under three oxygen levels (5, 10, and 21%). Key quality parameters, including moisture content, texture, color, flavor volatiles, and acrylamide content, were measured, and sensory evaluation was conducted using 55 judges. Principal component analysis was implemented to elucidate relationships among physicochemical properties, aroma profiles, and safety metrics. Results demonstrated that baking under low oxygen concentrations significantly reduced acrylamide formation, exemplified by a reduction from 95.8 to 58.5 μg/kg at 190 °C and 116.6 to 53.1 μg/kg at 210 °C, respectively. Notably, baking at 190 °C with 5% oxygen was identified as the optimal condition, balancing sensory quality and safety by minimizing the formation of harmful substances. These findings provide a promising strategy for improving the safety and quality of baked goods through controlled oxygen levels during processing.

Comprehensive characterization of Chinese beers based on chemical composition, antioxidant activity and volatile metabolomics

Four different commercial beers in the Chinese market were compared and analyzed systematically, in order to provide more guidance for consumers. In this experimental study, various physicochemical parameters such as alcohol content, color, bitterness, total acidity, and carbohydrates were evaluated. The total phenolics content was determined using the Folin-ciocalteu method, while the total flavone and melanoidins were measured using colorimetric and spectrophotometric methods, respectively. The antioxidant capacity was determined by ORAC, DPPH and ABTS assays. Non-targeted metabolomics was used to analyze the composition and differences of volatile compounds in different beers. The results indicated significant physicochemical variations among the four different commercial beers. The higher the chroma of beer, the greater the content of active substances, and the corresponding antioxidant capacity in vitro was also stronger. The alcohol content of the four beers ranged from 4.23 to 7.54% (ABV), the color values of the four beers ranged from 4.8 to 141.5 EBC, and the bitterness ranged from 11.2 to 36.6 IBU. The total phenolics content varied between 159.10 mg/ L and 269.13 mg/ L, the total flavone content was in the range of 39.94 -144.59 mg/L, and the melanoidins content was in the range of 271.07-296.68 mg/L. The antioxidant activity ranged from 0.570 mmol TE/L to 0.873 mmol TE/L (ABTS), from 3.700 mmol TE/L to 26.73 mmol TE/L (ORAC), and from 26.12 to 86.72% (DPPH clearance rate). A total of 453 volatile compounds were detected in the four beers, primarily comprising terpenoids (21.24%), esters (19.47%), heterocyclic compound (14.16%), alcohol (9.96%) and hydrocarbons (9.96%), etc. Compared to Premium lager beer, the other three kinds of beers had unique and common metabolites, with only 9 common metabolites. The flavors of the differential metabolites were mainly green, floral, sweet, fruity, etc.

Dynamic changes of volatile compounds during the processing of egg white powder based on GC-IMS investigation

Processing is a crucial stage in the production of egg white powder (EWP), yet its effect on flavor remains unclear. This study aimed to investigate the impact of processing on flavor in EWP by analyzing volatile compounds (VCs) using Gas Chromatography-Ion Mobility Spectrometry (GC-IMS). This study identified 29 VCs, with the highest diversity observed during fermentation, desugaring, and spray drying. Key flavor contributors, such as 1-penten-3-one and 2-ethyl-5-methylpyrazine, were identified, indicating specific processing conditions that enhance desirable flavors. The results suggest that specific processing techniques can significantly influence the flavor profile of EWP. This work can help optimize processing methods, enhance flavor profiles, and increase consumer acceptance of EWP products. Additionally, it demonstrates that GC-IMS can effectively monitor dynamic changes in flavor, offering valuable insights for future research and development.

Metabolomic and proteomic profiling reveals the formation mechanism of volatile flavor in egg whites during fermentation by Streptococcus thermophilus

In this study, the flavor of egg whites was significantly improved by lactic acid fermentation, and the metabolic networks of metabolites, volatile compounds, and enzymes were established using gas chromatography-mass spectrometry, metabolomic, and proteomic. Results indicate that among ten types of common lactic acid bacteria, Streptococcus thermophilus endowed egg white with the most pleasant flavor through increasing aldehydes, ketones, alcohols, esters, terpenoids, and aromatic compounds. Amino acid catabolism was the predominant pathway for generating most aldehydes, alcohols, acids, and esters. The changes in the organic acids and derivatives (mainly amino acids, peptides, and analogues) concentration during fermentation are attributed to the hydrolysis of egg white proteins by proteinases and peptidases, and the regulation of enzymes involved in amino acid biosynthesis and other reactions. This study provides a valuable reference for future investigations focusing on regulating the flavor release of egg whites.

Combining Sensory Analysis and Flavoromics to Determine How the Maillard Reaction Affects the Flavors of Golden Pomfret Hydrolysates

Enzymatic hydrolysis can enhance the flavor of aquatic products. Nevertheless, the strong fishy odor restricts its utilization in culinary applications. This study is centered on enhancing the flavor of golden pomfret samples by promoting the Maillard reaction (MR) between golden pomfret hydrolysate (GHES) and reducing sugars. The research results demonstrate that the Maillard reaction significantly improves the sensory characteristics of GHES. It prompts the formation of diverse volatile compounds, such as aldehydes, esters, and furans. Simultaneously, it reduces the relative amounts of substances associated with fishy odor, such as 1-Octen-3-ol and Hexanal. Moreover, the Maillard reaction increases the contents of amino acids contributing to umami and sweetness, as well as 5'-nucleotides in the samples, thus enriching their umami flavor profiles. After undergoing the Maillard reaction treatment, the antioxidant capacity of the samples is also significantly enhanced (p < 0.05). This research highlights the potential of the Maillard reaction in improving both the flavor and antioxidant properties of GHES, establishing a theoretical basis for elevating the quality of golden pomfret products.

Characteristics of Soft Wheat and Tiger Nut (Cyperus esculentus) Composite Flour Bread

This study investigated the effects of tiger nut flour (TNF) incorporation (5-25%) on wheat-based bread characteristics. Dough rheology analysis revealed optimal gas retention at 10% TNF addition, while higher concentrations decreased dough stability. Physical analysis demonstrated that 10% TNF substitution yielded the highest specific volume (2.4 mL/g) and porosity (67.0%), with significant textural changes observed at higher concentrations. Bioactive compound analysis showed progressive increases in the total polyphenol content and antioxidant activity with increasing TNF levels, particularly in 25% TNF bread (111.31 mg TE/g dm in crumb). Storage studies over 7 days indicated that TNF incorporation affected bread staling characteristics, with 10-15% substitution levels maintaining better textural properties. The results suggest that TNF incorporation up to 15% can enhance bread's nutritional value, while maintaining acceptable technological properties, with 10% substitution showing an optimal balance between functional benefits and bread quality.

Blue honeysuckle fermentation with Lacticaseibacillus rhamnosus L08 improves its biological activity, sensory and flavor characteristics, and storage stability

The objective of this study was to investigate the potential of Lacticaseibacillus rhamnosus L08 (L. rhamnosus L08) to enhance the functionality, improve the taste, and explore efficient storage methods of blue honeysuckle juice (BHJ). The fermentation process resulted in an increase in the levels of polyphenols, flavonoids, and anthocyanins in blue honeysuckle juice, which was attributed to the action of β-glucosidase on specific phenolic compounds, namely Cyanidin-3-Glucoside and Quinic acid. The increase in phenolic content resulted in an enhancement of the antioxidant capacity of BHJ. The fermentation processed, utilizing L. rhamnosus L08, not only enhanced the flavor and taste of BHJ, but also mitigated its bitter aftertaste while minimizing the loss of bioactive components during storage. In conclusion, this study demonstrated a potential avenue for enhancing the commercial value and dietary significance of this lesser-known superfruit, with fermented BHJ emerging as a promising innovation in the field of functional foods.

Innovations in nondestructive assessment of baked products: Current trends and future prospects

Rising consumer awareness, coupled with advances in sensor technology, is propelling the food manufacturing industry to innovate and employ tools that ensure the production of safe, nutritious, and environmentally sustainable products. Amidst a plethora of nondestructive techniques available for evaluating the quality attributes of both raw and processed foods, the challenge lies in determining the most fitting solution for diverse products, given that each method possesses its unique strengths and limitations. This comprehensive review focuses on baked goods, wherein we delve into recently published literature on cutting-edge nondestructive methods to assess their feasibility for Industry 4.0 implementation. Emphasizing the need for quality control modalities that align with consumer expectations regarding sensory traits such as texture, flavor, appearance, and nutritional content, the review explores an array of advanced methodologies, including hyperspectral imaging, magnetic resonance imaging, terahertz, acoustics, ultrasound, X-ray systems, and infrared spectroscopy. By elucidating the principles, applications, and impacts of these techniques on the quality of baked goods, the review provides a thorough synthesis of the most current published studies and industry practices. It highlights how these methodologies enable defect detection, nutritional content prediction, texture evaluation, shelf-life forecasting, and real-time monitoring of baking processes. Additionally, the review addresses the inherent challenges these nondestructive techniques face, ranging from cost considerations to calibration, standardization, and the industry's overreliance on big data.

Influence of germination and roasting on the characteristic volatile organic compounds of quinoa using sensory evaluation, E-nose, HS-GC-IMS, and HS-SPME-GC-MS

This study aimed to investigate the effects of germination and roasting on the flavor of quinoa. Firstly, the aroma of quinoa and germinated quinoa roasted under different conditions was analyzed using sensory evaluation and electronic nose (E-nose). Results showed that the best favorable aroma of quinoa and germinated quinoa was obtained when roasted at 160 °C for 15 min. Then, a total of 34 and 80 volatile organic compounds (VOCs) of quinoa and germinated quinoa roasted at 160 °C for 15 min were determined using headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS), respectively. Germination and roasting effectively reduced the contents of VOCs that produced undesirable flavor. Moreover, germination improved the floral aromas, while roasting mainly produced caramel, cocoa, and roasted nut aromas of quinoa. This study indicated that germination and roasting treatments might serve as promising processing methods to improve the flavor of quinoa.

Comparison and evaluation of L. reuteri and L. rhamnosus-fermented egg yolk on the physicochemical and flavor properties of cookies

The study aims to explore an effective approach to improve the sensory quality and consumer satisfaction of cookies in the food industry. L. reuteri and L. rhamnosus were chosen to ferment egg yolk and their effects on dough properties and physicochemical properties, flavor, texture, color, and sensory acceptability of cookies were studied. Results show that the utilization of fermented egg yolk significantly decreased baking loss and increased spread factor of cookies. GC-MS analysis indicates different Lactobacillus species enhanced cookie flavor through unique mechanisms. Texture analysis shows cookies prepared with L. rhamnosus-fermented egg yolk had significantly lower hardness (1807.12 g) than control cookies (2028.34 g). Sensory evaluation reveals the L. reuteri-fermented egg yolk significantly improved the overall acceptability of cookies by enhancing appearance, flavor, and mouthfeel scores. These findings have practical implications for food manufacturers seeking to enhance their product's quality and appeal, thereby gaining a competitive edge in the market.

A primary study of ethanol production in postmortem liver and muscle tissue of rats

OBJECTIVE

To study the characteristics of postmortem ethanol production and its relation with alcohol congeners in postmortem rat liver and muscle tissues.

METHOD

Postmortem liver and muscle tissues in Sprague-Dawley rats, from postmortem time interval (PMI) day 0-20, were analyzed via headspace gas chromatograph flame ionization detection to observe production of postmortem ethanol and 5 selected alcohol congeners.

RESULT

1. Putrid ethanol production increased gradually to a peak and then decreased with the prolongation of PMI; 2. Acetaldehyde, 1-propanol, and 3-methyl-butyraldehyde were produced along with postmortem ethanol; 1-butanol was only detected from day 11-20; 3. The concentrations of acetaldehyde, 1-propanol and 3-methyl-butyraldehyde was related with ethanol production. Fifteen mathematical models were constructed for putrid ethanol production based on acetaldehyde, 1-propanol, and 3-methyl-butyraldehyde.

CONCLUSION

A peak in postmortem ethanol production was identified. The production trends of acetaldehyde, 1-propanol, and 3-methyl-butyraldehyde in the liver, and of 1-propanol in muscle, were consistent with those of ethanol, and could potentially to be used as biomarkers of postmortem ethanol production. Further human samples and data analysis are needed to verify this.

Pyrazines in food samples: Recent update on occurrence, formation, sampling, pretreatment and analysis methods

Pyrazines are a class of active aromatic substances existing in various foods. The accumulation of pyrazines has an impact on flavor and quality of food products. This review encompasses the formation mechanisms and control strategies of pyrazines via Maillard reaction (MR), including the new reactants and emerging techniques. Pyrazines characteristics are better understood through the developed sample pretreatments and detection methods. Herein, an in-depth review of pretreatments and analysis methods since 2010 is presented to explore the simple, fast, green, and effective strategies. Sample preparation methods include liquid phase extraction, solid phase extraction, supercritical fluid extraction, and microextraction methods such as liquid phase microextraction, and solid phase microextraction, etc. Detections are made by chromatographic methods, and sensors, etc. Advantages and limitations are discussed and compared for providing insights to further studies.

Exploring the interaction between myofibrillar proteins and pyrazine compounds: Based on molecular docking, molecular dynamics simulation, and multi-spectroscopy techniques

Flavor is one of the most important factors that affect consumers' preference for processed meat products. This study aimed to investigate effects of heating on interaction between myofibrillar proteins (MPs) and pyrazine compounds and understand the underlying mechanisms. A combination of multispectral, molecular docking, and molecular dynamics technologies was used to achieve study's aim. Results demonstrated that MPs underwent structural reconstruction and expansion during heating, which significantly altered surface hydrophobicity and SH content. MPs' zeta potential reduced from -7.29 to -10.47 when a short heating time. Additionally, a positive correlation was found between β-sheet content and ability of MPs to adsorb pyrazine compounds. Molecular docking analysis revealed 13 binding sites for pyrazines and MPs. Furthermore, amino acid residues and pyrazine compounds were found to interact by four different forms of forces, primarily van der Waals forces, carbon‑hydrogen bonds, alkyl groups, and π-alkyl groups. Obtained results demonstrated that adequate or optimized heat treatment could expose more binding sites, hence enhancing the binding of MPs to pyrazine compounds. This study may be used to better understand how structural changes in MPs during processing affect MPs' capacity to bind flavor substances, which can help improve flavor of processed meats to encourage their consumption.

Tiger nut (Cyperus esculentus L.) oil: A review of bioactive compounds, extraction technologies, potential hazards and applications

Tiger nut is a tuber of a plant native in the Mediterranean coastal countries, which is of great interest in food industry due to its richness in carbohydrates, lipids, starches, minerals, etc. Recent studies have focused on the analysis of the phytochemical composition of tiger nut, including six essential nutrients, polyphenols, and the extraction of proteins, starches, and phenolic compounds from the by-products of tiger nut milk 'horchata'. Few works were focused on the possibility of using tiger nut oil, a nutritious oil comparable to olive oil, as an edible oil. Therefore, this review discussed some extraction technologies of tiger nut oil, and their effects on the properties of oil, such as bioactive compounds, oxidative stability and potential hazards. The information on the emerging applications of tiger nut oil was summarized and an outlook on the utilization of tiger nut oil by-products were also reviewed.

Comparison of Flavor Profile Relationship of Soy Sauce under Different Storage Conditions

To elucidate the relation of flavor in soy sauce (SS) kept at room temperature (SSAT) and SS kept under accelerated aging condition (SSAA), four analytical instruments, including electronic nose (E-nose), electronic tongue (E-tongue), gas chromatography-mass spectrometry-olfactory combined with solvent assisted flavor evaporation, and amino acid analyzer, were applied for analyzing the overall flavor profiles and flavor constituents in SSAT and SSAA. The results of E-nose and E-tongue showed overall flavor profile in SSAT for 3 weeks was similar to that of SSAA for 1 week, and 6 weeks (SSAT) was similar to 2 weeks (SSAA). In SS, a total of 35 odor-active compounds were identified and quantitated, and 22 compounds with odor activity value ≥1 were determined as key odorants. The compounds with the highest concentration were 4-hydroxy-2,5-dimethyl-3(2H)-furanone (28,756 μg/mL), followed by acetic acid (8838 μg/mL) and maltol (7984 μg/mL). The heatmap and hierarchical cluster analysis indicated that the concentrations of key odorants and amino acids in SSAT for 3 weeks was close to those of SSAA for 1 week, and 6 weeks (SSAT) was similar to 2 weeks (SSAA). Based on the results obtained above, it was concluded that the flavor changes in SSAA for 1 week were equivalent to those in SSAT for 3 weeks.

Selection of a Fermentation Strategy for the Preparation of Clam Sauce with Acceptable Flavor Perception

Flavor, which mainly depends on volatile compounds, is an important index for evaluating the quality of clam sauce. This study investigated the volatile compounds in clam sauce prepared using four different methods and the influence of aroma characteristics. Fermenting a mixture of soybean koji and clam meat improved the flavor of the final product. Solid-phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) identified 64 volatile compounds. Nine key flavor compounds, namely, 3-methylthio-1-propanol, 2-methoxy-4-vinylphenol, phenylethyl alcohol, 1-octen-3-ol, α-methylene phenylacetaldehyde, phenyl-oxirane, 3-phenylfuran, phenylacetaldehyde, and 3-octenone, were selected using variable importance in projection (VIP). The results of the electronic nose and tongue detection of the aroma characteristics of the samples prepared by four different fermentation methods were consistent with those of GC-MS analysis. The clam sauce prepared by mixing soybean koji with fresh clam meat possessed better flavor and quality than that prepared via other methods.

Vacuum Concentration Improves the Quality and Antioxidant Capacity of Pear Paste

A vacuum concentration method was established to produce pear paste using fresh pear juice in this study. The optimal condition was determined by comparing the quality indexes, contents of total phenol and flavonoid, and antioxidant properties of the pear paste produced by traditional heating concentration and vacuum concentration. Electronic nose and electronic tongue were introduced in this study to provide digital smell and taste indicators. The results showed that the best vacuum concentration temperature was 65°C, which led to the best sensory evaluation score and pear paste quality. The browning degree and soluble quinones were the lowest in all tested temperatures, and the content were 60.12% and 72.88% compared with the heating method, respectively. While the values were 148.29%, 209.44%, 310.86%, 120.37%, 106.24%, and 181.26% of total phenol, total flavonoid, vitamin C, 1,1-diphenyl-2-trinitrophenylhydrazine (DPPH) and hydroxyl (·OH) radical scavenging rates, and total reducing power, respectively. The electronic nose could effectively distinguish the vacuum-concentrated pear paste from the traditional heating-concentration pear paste and could provide quality guidance on their flavor differences through characteristic sensors. The electronic tongue tests showed that the vacuum-concentrated pear paste had larger freshness and richness kurtosis. The pear paste made by the optimized vacuum concentration method had higher retention of nutritional and functional components and higher antioxidant capacity, which could be clearly differentiated from the traditional process, thus this method had an applicable potential.