Influence of proteolytic enzyme treatment on the changes in volatile compounds and odors of beef longissimus dorsi

Reheating-induced gel properties change and flavor evolution of surimi-based seafood: Effects and mechanisms

This study investigated the effect of different reheating treatments on gel properties and flavor changes of surimi products. As the reheating temperature increased from 90 °C to 121 °C, the heat-induced proteolysis produced more abundant umami and sweet amino acids, which took part in the conversion of IMP to AMP, thus enhancing the taste profiles. Reheating increased the exposure of active -NH2 terminals in proteins, which boosted Maillard and Strecker reactions with carbonyl compounds originated from fatty acid oxidation, thus not only reducing the aldehydes and esters contents but also lowering the whiteness of surimi products. Reheating at 90 °C prohibited the production of warmed-over flavor (WOF) and well-preserved the textural characteristics, but high temperatures ≥100 °C were prone to generate furan as the major WOF substance and to destroy gel structures. Collectively, this study provides new insights on understanding the role of reheating on sensory properties of surimi products.

Research Progress on the Mechanism of the Impact of Myofibrillar Protein Oxidation on the Flavor of Meat Products

Myofibrillar proteins primarily consist of myosin, actin, myogenin, and actomyosin. These proteins form complex networks within muscle fibers and are crucial to the physical and chemical properties of meat. Additionally, myofibrillar proteins serve as significant substrates for the adsorption of volatile flavor compounds, including aldehydes, alcohols, ketones, and sulfur and nitrogen compounds, which contribute to the overall flavor profile of meat products. A series of chemical reactions occur during the processing, storage, and transportation of meat products. Oxidation is one of the most significant reactions. Oxidative modification can alter the physical and chemical properties of proteins, ultimately impacting the sensory quality of meat products, including flavor, taste, and color. In recent years, considerable attention has been focused on the effects of protein oxidation on meat quality and its regulation. This study investigates the impact of myofibrillar protein oxidation on the sensory attributes of meat products by analyzing the oxidation processes and the factors that initiate myofibrillar protein oxidation. Additionally, it explores the control of myofibrillar protein oxidation and its implications on the sensory properties of meat products, providing theoretical insights relevant to meat processing methods and quality control procedures.

Creating alternative seafood flavour from non-animal ingredients: A review of key flavour molecules relevant to seafood

This review summarises current knowledge of the molecular basis for flavour profiles of popular seafood types (crustacean (crab, lobster, prawn, etc.), mollusc (oyster, squid, etc.), oily fish (salmon, sardine, etc.) and white fish (barramundi, turbot, etc.)), and provides a foundation for formulating improved plant-based seafood alternative (PBSA) flavours. Key odour-active volatile molecules were identified from a systematic review of published olfactometry studies and taste-active compounds and macronutrient profiles of different seafood species and commercial PBSAs from nutrition databases were compared. Ingredients commonly used in commercial BPSAs and new potential sources of flavouring agents are evaluated. While significant challenges in replicating seafood flavour and texture remain, this review provides some insights into how plant-based ingredients could be applied to improve the acceptability of PBSAs.

Understanding the Role of Filamentous Actin in Food Quality: From Structure to Application

Actin, a multifunctional protein highly expressed in eukaryotes, is widely distributed throughout cells and serves as a crucial component of the cytoskeleton. Its presence is integral to maintaining cell morphology and participating in various biological processes. As an irreplaceable component of myofibrillar proteins, actin, including G-actin and F-actin, is highly related to food quality. Up to now, purification of actin at a moderate level remains to be overcome. In this paper, we have reviewed the structures and functions of actin, the methods to obtain actin, and the relationships between actin and food texture, color, and flavor. Moreover, actin finds applications in diverse fields such as food safety, bioengineering, and nanomaterials. Developing an actin preparation method at the industrial level will help promote its further applications in food science, nutrition, and safety.

Effect of Different Cooking Methods on the Aroma and Taste of Chicken Broth

A single combi oven, known for its versatility, is an excellent choice for a variety of chicken soup preparations. However, the impact of universal steam ovens on the flavor quality of chicken soup remains unclear. This study aimed to explore the impact of different cooking methods on the aroma and taste of chicken soup. Three cooking methods with various stewing times were compared: ceramic pot (CP), electric pressure cooker (EPC), and combi oven (CO). Analyses were conducted using electron-nose, electron-tongue, gas chromatography-ion mobility spectrometry (GC-IMS), automatic amino acid analysis, and chemometric methods. A total of 14 amino acids, including significant umami contributors, were identified. The taste components of CP and CO chicken soups were relatively similar. In total, 39 volatile aroma compounds, predominantly aldehydes, ketones, and alcohols, were identified. Aldehydes were the most abundant compounds, and 23 key aroma compounds were identified. Pearson's correlation analyses revealed distinct correlations between various amino acids (e.g., glutamic acid and serine) and specific volatile compounds. The aroma compounds from the CP and CO samples showed similarities. The results of this study provide a reference for the application of one-touch cooking of chicken soup in versatile steam ovens.

Proteomics analysis of the influence of proteolysis on the subsequent glycation of myofibrillar protein

Proteomics was used to study the influence of proteolysis on the glycation of myofibrillar proteins (MPs). Proteolysis by papain and proteinase K generated the highest level of amino acids (AAs) and peptides, respectively. Both the glycation degree (A value increased from 0.173 to 0.202-0.348) and speed (k value increased from 0.0099 to 0.0132-0.0145) were enhanced by proteolysis using papain and proteinase K. Proteomics analysis revealed that proteolysis largely enhanced the glycation site number in Lys, Arg and N-terminal residues (eg. Leu, Gly, Thr, Ala, Met, Ile, Phe and Val residues in myosin light chain). Proteolysis by papain preferentially acted on actin and therefore specifically increased the glycation sites from actin. Proteolysis reduced the level of aldehydes but enhanced the aromatic E-nose signals, possibly due to the combination of aldehydes with released AAs/peptides. The proteomics analysis helped to detail the relationship between proteolysis and subsequent glycation/flavour formation.

Evaluation of umami taste in Hanwoo with different feed sources by chemical analysis, electronic tongue analysis, and sensory evaluation

This study aimed to evaluate umami taste in Hanwoo with different feed by chemical analysis, sensory evaluation and an electronic tongue system. Hanwoo cattle were divided into three groups: control group (fed only total mixed ration [TMR]), T1 (fed soybean meal + TMR), and T2 (fed soybean meal + corn-dried distiller's grain with solubles [Corn DDGS] + TMR). The three most abundant fatty acids (C18:1n-9, C16:0, and C18:0) in the T1, T2, and control groups accounted for 83.63%, 86.07%, and 85.52% of the total fatty acid content, respectively. Umami taste-related glutamic acid levels were significantly high in T1 (109.89 mg/kg), followed by T2 (66.66 mg/kg) and control (47.27 mg/kg). Fatty acid levels showed a high correlation with umami taste. The results of this study showed that the amino acid and fatty acid levels had been affected by feed types and soybean- or Corn DDGS-based feed potentially enhanced Hanwoo's umami flavor.

Flavor evolution of normal- and low-fat Chinese sausage during natural fermentation

This work compared the flavor evolution of normal-fat (NF) with that of low-fat (LF) Chinese sausage during natural fermentation. Higher degree of lipid oxidation occurred in NF sausages, resulting in its faster formation of stable volatile profiles. Faster formation of esters occurred in NF sausage in the initial 10 days, whereas prolonged fermentation reduced the level of ethyl lactate-M, ethyl heptanoate, ethyl hexanoate-D and ethyl pentanoate-D. Gradual reduction of alcohols was observed in both groups, and surge in aldehydes occurred in LF samples during day 20-30 period. Faster formation of taste characteristics and larger amount of 2-methylfuran as well as 2,3-dimethylpyrazine were found in LF sausages, since more free amino acids were liberated in LF sausages. Umami and aftertaste tastes formed in the first 20 days, whereas prolonged fermentation reduced these favorable taste. These results highlight that the choice of proper fermentation duration should largely depend on the fat content in Chinese sausages.

Influence of aging temperature and duration on spoilage organism growth, proteolytic activity, and related chemical changes in vacuum-packaged beef longissimus

Each carcass was assigned to a storage temperature (-2, 0, 4℃). Strip loins were portioned into half loins and assigned to an aging duration (14, 28, 42, 56 d) and vacuum packaged. Loins were aged in commercial upright refrigerators. At each aging interval, loin portion packages were aseptically opened and loins were surface swabbed for microbial analysis before fabrication into 2.54 cm strip steaks. Steaks assigned to slice shear force (SSF) were cooked to 71℃. A raw steak was used to track proteolytic activity, free amino acid content, and volatile compounds. Two-way interactions were observed for all spoilage organisms (P < 0.001). Aging for 42 and 56 d at -2℃ produced lower microbial counts compared to 4℃ (P < 0.05).  Loins aged for 14 d at 4℃ had increased desmin and troponin-T degradation compared to aging for 14 at -2 and 0℃ (P < 0.05). Loins aged in 4These data indicate aging at 4℃ increases the rate of proteolysis and subsequent tenderness development and flavor precursor accumulation. However, extended aging at 4℃ resulted in increased microbial counts. Many traits peaked at 42 d of aging.

Influence of Proteolysis on the Binding Capacity of Flavor Compounds to Myofibrillar Proteins

Proteolysis occurs extensively during postmortem aging, enzymatic tenderization and fermentation of meat products, whereas less is understood regarding how proteolysis affects meat flavor. Myofibrillar proteins (MP) were extracted from beef longissimus dorsi muscle and subsequently treated with three commercial proteases. The effect of proteolysis on the interactions between the treated MP and butyraldehyde, 2-pentanone, octanal and 2-octanone was investigated. The progress of proteolysis increased the degree of hydrolysis (DH) and the surface hydrophobicity but decreased the turbidity and particle size. Fluorescence-quenching analysis results indicated that the enzymatic treatment generally increased the quenching constant (Ksv) between the treated MP and ketones but decreased the Ksv between the treated MP and aldehydes, and the papain treatment changed the Ksv value to a larger degree than treatment with proteinase K and bromelain. The adsorption assay showed that the proteinase K treatment largely increased the adsorption capacity of the MP to octanal (by 15.8−19.3%), whereas the bromelain treatment significantly reduced the adsorption capacity of the treated MP to butyraldehyde (by 6.0−7.9%) and 2-pentanone (by 9.7−11.9%). A correlation analysis demonstrated a strong positive correlation (0.859, p < 0.05) between the DH of the MP and the adsorption ability of the treated MP to octanal. This study highlighted the significant but complex influence of proteolysis on MP binding capacity to flavor compounds.

Insight into the effect of frozen storage on the changes in volatile aldehydes and alcohols of marinated roasted beef meat: Potential mechanisms of their formation

This study aimed to evaluate the effect of frozen storage on the changes in volatile aldehydes (VAs), volatile alcohols (VCs), lipid oxidation, and fatty acid composition of marinated roasted beef meat. Thirty VAs and VCs were identified in all meat samples by using headspace solid-phase microextraction-gas chromatography-mass spectrometry. The total concentrations of VAs increased with storage periods up to four months and gradually decreased. Whereas the total concentrations of VCs decreased with prolonged storage periods. The contents of thiobarbituric acid reactive substances and hexanal increased with prolonged storage periods in all samples until four months and then gradually decreased except the hexanal contents in the control sample (BS1), which showed an increase up to six months. Saturated and monounsaturated fatty acids decreased after storage in all samples except the control. By contrast, polyunsaturated fatty acids increased with prolonged storage in all samples. The correlation analysis showed the positive correlation of flavor compounds with fatty acids, E-nose, and sensory notes.

Effect of frozen storage on the lipid oxidation, protein oxidation, and flavor profile of marinated raw beef meat

This study aimed to evaluate the effects of long-term frozen storage on the lipid oxidation, protein oxidation, and flavor profile of marinated raw beef meat. Twenty-eight volatiles were identified in all the samples during different times of frozen storage using HS-SPME-GC-MS. Frozen storage affected the contents of flavor compounds, in which their concentrations fluctuated along with the frozen storage. Partial least squares-discriminant analysis screened six flavors as markers, indicating the effect of frozen storage in all the beef samples. They included octanal, 2-ethyl-1-hexanol, benzeneacetaldehyde, 1-heptanol, isoeugenol, and hexanal. Most of the screened markers belonged to aldehydes and alcohols, indicating that these components were derived from lipid oxidation. Thiobarbituric acid reactive substances significantly increased in the first two months of frozen storage and then decreased slightly. Carbonyl content was increased linearly in all the samples during frozen storage.

Evaluation of the effect of marination in different seasoning recipes on the flavor profile of roasted beef meat via chemical and sensory analysis

Marinating is a Chinese meat-processing technique that involves treating meat products in an aged brine containing traditional Chinese spices and other condiments. In this study, beef meats were marinated in different seasoning recipes, including marinade solution of water as control (BS1), marinade solution consisting of water and 2% salt (BS2), marinade solution consisting of water, 2% salt, and 0.5% sugar (BS3), and marinade solution consisting of water, 2% salt, 0.5% sugar, 0.5% soy sauce, and spices (BS4). The effects of different marinade solutions through the tumbling on the flavor profile of roasted beef meat were comprehensively analyzed via chemical and sensory analysis. A total of 82 volatile flavor compounds were identified. Among them, 36 compounds were identified in BS1, 40 compounds in BS2, 46 compounds in BS3, and 64 compounds in BS4. Besides, 4 compounds showed high odor activity values (OAVs) in marinated samples, including decanal, trans-2-decenal, linalool, and nonanal. The metal oxide sensors of E-nose distinguished the differences among the different marinated samples. Marinated beef samples BS2 and BS3 showed a significant increase in the values of thiobarbituric acid reactive substances (TBARS). In contrast, marinated beef sample BS4 significantly reduced TBARS value to 4.11 µg MDA/kg beef. It can be concluded that using this different seasoning processing enhances the aroma profile and provides a reference for the production of marinated meat products. PRACTICAL APPLICATIONS: Marinating is a Chinese meat-processing technique that involves treating meat products in an aged brine containing traditional Chinese spices and other condiments. Processing beef meat with different marinade solutions could enhance its aroma profile. Therefore, this study aimed to evaluate the effect of marination in different marinade solutions through the tumbling on the volatile flavor compounds of roasted beef meat using HS-SPME-GC-MS and E-nose. The obtained results from this study could enrich the theoretical knowledge of the flavor chemistry of marinated beef meat and provide a reference for the production of marinated meat products.

Effects of bromelain on the quality of smoked salted duck

This study was aimed to assess the effects of bromelain on the eating quality of smoked salted duck. Whole ducks were marinated with different doses of bromelain (300 U/g, 600 U/g, 900 U/g, 1,200 U/g and 1,500 U/g), while the group without bromelain was considered as control (CK). After the production of smoked salted duck was completed, the pH, color, texture, electronic tongue detection, thiobarbituric acid reactive substances (TBARS), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and mass spectrometry analysis were determined. The results showed that, compared to CK, the pH, TBARS and hardness values in 900, 1,200 and 1,500 U/g groups were reduced. The cohesiveness and the springiness were increased while the values of b* were decreased in all bromelain treatments (p < .05). The SDS-PAGE and mass spectrometry analysis indicated that myosin and actin were further hydrolyzed into small-molecule proteins by bromelain. Electronic tongue detection showed that the umami, the saltiness and the richness of smoked salted duck were enhanced, while the bitterness was reduced at the dose of 900 U/g. Thus, bromelain improved the eating quality of smoked salted duck in particular at the level of 900 U/g.

Effects of an Extract from Olive Fruits on the Physicochemical Properties, Lipid Oxidation and Volatile Compounds of Beef Patties

The aim of this work was to evaluate the effect of an olive extract (OE) on the physicochemical and microbiological characteristics, lipid oxidation and volatile compounds of beef patties stored both aerobically and under modified atmosphere packaging for 15 days at 4 °C. The antioxidant and antimicrobial effects of the OE were compared to those of sulfite. Four formulations were elaborated according to the antioxidant and dose used: without antioxidant, C; 300 mg potassium metabisulfite/kg product, S; 150 mg OE/kg product, OE1; and 250 mg of OE/kg product, OE2. The parameters analyzed were pH, water activity, color, lipid oxidation (TBARS and volatile organic compounds: hexanal, 2-pentyl-furan, 1-pentanol, 2,3-octanedione and nonanal, 1-octen-2-ol) and total viable counts. The OE delayed the loss of the bright red color of the patties and reduced the lipid oxidation in both types of packaging compared to the control patty. Sulfite was the most effective antioxidant for inhibition of the total viable counts. An OE could be used as a natural antioxidant to delay the lipid oxidation of meat without negatively affecting its physicochemical properties.

How Volatile Compounds, Oxidative Profile and Sensory Evaluation Can Change with Vacuum Aging in Donkey Meat

Simple Summary

Aging in donkey meat was never investigated. It represents an important process, because it leads the muscle to become meat. There are many ways to age meat, and vacuum aging is one of these. The present paper characterised donkey meat Volatile Organic Compounds (VOCs) production during 14 vacuum aging days, its oxidative status and the consequent sensory evaluation. Lipid oxidative processes are delayed, but some protein oxidative processes happen, influencing VOCs production and sensory evaluation.

Abstract

This study aims to improve knowledge on donkey meat and the vacuum aging effect on the Volatile Organic Compounds (VOCs), oxidative profile and status and the sensory characteristics. Ten 18-month old Martina Franca donkeys’ male foals were involved in the trial. Longissimus thoracis (LT) muscle was extracted from each left half carcass, between the fourth and the ninth rib. Each muscle was divided into five sections, vacuum packaged, stored at 2 °C, and randomly assigned to one of the different aging time (1, 3, 6, 9, and 14 days of aging). Volatile compounds, oxidation parameters, and antioxidant enzymes were analysed, and a sensory test was performed. A nested one-way analysis of variance (ANOVA) was performed for aging time as an independent variable. Significance was set at p < 0.05. Aldehydes are the most produced VOCs, but no changes were observed during vacuum aging (p > 0.05). Nitrogen compounds increased during aging (p < 0.01). TBARs and hydroperoxides did not change during the storage, whereas the protein carbonyls increased (p < 0.05). Vacuum aging slowed down lipid oxidation and put in evidence the presence of protein oxidation and degradation, influencing the VOCs productions and sensory evaluation.