Fast and dynamic descriptive techniques (Flash Profile, Time-intensity and Temporal Dominance of Sensations) for sensory characterization of dry-cured loins

Multi-attribute temporal descriptive methods in sensory analysis applied in food science: A systematic scoping review

Among descriptive sensory evaluation methods, temporal methods have a wide audience in food science because they make it possible to follow perception as close as possible to the moment when sensations are perceived. The aim of this work was to describe 30 years of research involving temporal methods by mapping the scientific literature using a systematic scoping review. Thus, 363 research articles found from a search in Scopus and Web of Science from 1991 to 2022 were included. The extracted data included information on the implementation of studies referring to the use of temporal methods (details related to subjects, products, descriptors, research design, data analysis, etc.), reasons why they were used and the conclusions they allowed to be drawn. Metadata analysis and critical appraisal were also carried out. A quantitative and qualitative synthesis of the results allowed the identification of trends in the way in which the methods were developed, refined, and disseminated. Overall, a large heterogeneity was noted in the way in which the temporal measurements were carried out and the results presented. Some critical research gaps in establishing the validity and reliability of temporal methods have also been identified. They were mostly related to the details of implementation of the methods (e.g., almost no justification for the number of consumers included in the studies, absence of report on panel repeatability) and data analysis (e.g., prevalence of use of exploratory data analysis, only 20% of studies using confirmatory analyses considering the dynamic nature of the data). These results suggest the need for general guidelines on how to implement the method, analyze and interpret data, and report the results. Thus, a template and checklist for reporting data and results were proposed to help increase the quality of future research.

Sodium Reduction in Traditional Dry-Cured Pork Belly Using Glasswort Powder (Salicornia herbacea) as a Partial NaCl Replacer

Sodium chloride (NaCl) is a key ingredient in the processing of traditional dry-cured meat products by improving microbial safety, sensory attributes and technological properties. However, increasing concern about the consumption of sodium and health has been supporting the development of low-sodium meat products. Several strategies to reduce sodium in dry-cured meat product have been tested, although the followed approaches sometimes result in undesirable characteristics concerning flavor, texture and mouthfeel. The use of halophytic plants such as glasswort (Salicornia herbacea) in food matrices has been suggested as a novel strategy to reduce sodium content, due its salty flavor. The main aim of the present study is to produce traditional dry-cured pork bellies from the Bísaro breed using glasswort as a NaCl partial replacer, and compare it with dry-cured bellies salted either with NaCl or a mix of NaCl + KCl. Control bellies (BC) were salted with 100% of NaCl, the second formulation (BK) had 50% of NaCl and 50% of KCl, and the third formulation (BG) had 90% of NaCl and 10% of glasswort powder (GP). After production, the bellies were evaluated for a_w, pH, CIELab coordinates, weight loss, proximal composition, TBARS, collagen and chloride contents, fatty acid profile and sensory attributes. The use of BG in dry-cured pork bellies did not affect processing indicators such as weight loss, a_w and pH. Concerning CIELab, only the coordinates L* and hue angle from the external surface color of BG were statistically different from BC and BK. As expected, ash and NaCl contents differed from BG to the other two formulations. SFA and indexes AI and TI were lower, whereas the MUFA and h/H ratio were higher in BG than other treatments, leading to a product with a healthier lipid profile. The sensory evaluation revealed differences in appearance, taste and flavor among treatments, but did not indicate any negative effects of BG in the product attributes. This study reinforces the potential of BG as a natural sodium reducer for the production of traditional dry-cured pork bellies.

Application of Food Mechanics and Oral Processing in Modelling First Bite of Grilled Meat

This study analyzed the potential of modelling meat mastication by using pork and poultry meat as food with different physical properties under different grilling temperatures. For the purpose of modelling oral processing, temporal dominance of sensations and finite element methods were employed. A panel with ten subjects was trained and used for oral processing analysis and temporal dominance of sensations revealing in-mouth sensations and mastication characteristics. In parallel, the second aim was to evaluate the mechanical properties of the samples and explore the potential of simulating the first bite using the finite element method. Based on the textural parameters, a 3D model of grilled meat was created and a first-bite simulation was performed. A higher level of differences was observed comparing the number of chews for pork meat compared to poultry meat. The chewing rate showed a statistical difference with values in the range of 1.31 chews/s to 1.46 chews/s for pork meat and between 1.36 chews/s and 1.42 chews/s for poultry meat. Firmness was the predominant sensory attribute recognized by panelists at the beginning of mastication, which confirmed our approach used for first-bite modelling. Simulation results show the growth of internal stress following the jaw’s path. Presented models demonstrate that the highest values are around teeth pressure and lead to a conclusion that upon biting, the meat structure will suffer irreversible damage dividing the grilled meat into two pieces, as it happens during the first bite. The main conclusion of this study is that by combining results from oral processing and testing of mechanical properties of the grilled products, it is possible to simulate the first bite.

Formation and Analysis of Volatile and Odor Compounds in Meat-A Review

The volatile composition and odor of meat and meat products is based on the precursors present in the raw meat. These are influenced by various pre-slaughter factors (species, breed, sex, age, feed, muscle type). Furthermore, post-mortem conditions (chiller aging, cooking conditions, curing, fermentation, etc.) determine the development of meat volatile organic compounds (VOCs). In this review, the main reactions leading to the development of meat VOCs such as the Maillard reaction; Strecker degradation; lipid oxidation; and thiamine, carbohydrate, and nucleotide degradation are described. The important pre-slaughter factors and post-mortem conditions influencing meat VOCs are discussed. Finally, the pros, cons, and future perspectives of the most commonly used sample preparation techniques (solid-phase microextraction, stir bar sorptive extraction, dynamic headspace extraction) and analytical methods (gas chromatography mass spectrometry and olfactometry, as well as electronic noses) for the analysis of meat VOCs are discussed, and the continued importance of sensorial analysis is pinpointed.

Dry-cured loin characterization by ultrasound physicochemical and sensory parameters

The aim of this study was to evaluate the ability of ultrasound inspection and quality determinations to characterize two commercial categories of dry-cured pork loin, labelled as green (GL) and red (RL). For this objective, ultrasound inspection was carried out for two different frequencies (500 and 1000 kHz), considering parameters of ultrasonic pulse velocity (UPV), frequency components related to the fast Fourier transform (FFT), and variables related to the attenuation. Physicochemical (moisture and fat content, water activity, instrumental color), instrumental texture (TPA) and sensory analyses (QDA) were also carried out. Moreover, quality and ultrasonic parameters were subjected to a correlation analysis (Pearson). Several physicochemical, instrumental texture and sensory parameters allowed to discriminate the dry-cured loin category. Moreover, high significant correlations were found among quality and acoustics parameters. Thus, ultrasound inspection can determine quality parameters indirectly without the limitations of traditional methodologies, postulating as a tool for characterizing dry-cured loin samples of different category with a promising predictive nature. This work has showed new findings for dry-cured meat products that may be of interest to the meat industry.

Structural Equation Modeling (SEM) and Temporal Dominance of Sensations (TDS) in the Evaluation of DOC Douro Red Wine's Sensory Profile

In the Portuguese Douro region, several DOC (Denomination of Controlled Origin) Douro red wines are produced and, due to the peculiar characteristics of the three Douro sub-regions, present particular imprinted terroirs, that can be perceived when tasted. Considering the DOC Douro wine’s sensory profile and terroir, this study aimed to analyze the sensory characteristics of red wines produced in the three Douro sub-regions (Baixo Corgo, Cima Corgo, and Douro Superior) by a single point sensory technique, a Quantitative Descriptive Analysis—QDA^® and also applying a temporal method-TDS (Temporal Dominance of Sensations). The use of QDA and TDS methods proved to be efficient in the wine’s sensory profile characterizing. The QDA^® method allowed a detailed classification of attributes; however, the TDS method proved to be much more efficient. Moreover, the wines of the three sub-regions presented profiles with characteristics very similar in olfactory and taste/flavor aspects, pointing out a huge relation between the characteristics of the three sub-regions and the grape varieties present in the wines. Globally, the olfactory profile of wines is characterized by Fruity, Floral, and Balsamic aromatic notes, while the taste/flavor profile stands out, highlighting Astringency and Acidity and, again, Fruity as the main in-mouth aroma. It was also possible to conclude that TDS is a fast method that is easy to apply and has excellent results in the evaluation of the olfactory and taste/flavor profile of wines and, with a larger set of samples, it would be possible to obtain characteristic TDS curves for each Douro sub-region, providing a wine’s fingerprint that could be used for authentication and traceability purposes.

Temporal Sensory Profiles of Regular and Sodium-Reduced Foods Elicited by Temporal Dominance of Sensations (TDS) and Temporal Check-All-That-Apply (TCATA)

Temporal sensory methods can be used to highlight the impact of sodium reduction on the dynamic sensory profile of foods targeted for sodium reduction. Study aims were to compare the temporal sensory attribute profiles of regular and sodium-reduced food products elicited by TDS and TCATA, over single and multiple oral intakes. A total of 20 semi-trained participants evaluated commercially available regular and sodium-reduced canned corn, cooked ham (single intakes), potato chips and cream of mushroom soup (5 intakes) using both TDS and TCATA. Regular and sodium-reduced products differed in not only salty but also other sensory attributes, noticeably dry for chips, sweet for corn, bitter and metallic for ham, thick, creamy, sweet, and starchy for soup. TDS and TCATA provided comparable information for the key sensory attributes characterizing and differentiating the regular and sodium-reduced products. TDS profiled significant differences between samples for a larger number of attributes than TCATA, while TCATA profiles were more consistent across intakes. Multiple intakes changed the duration of attribute dominance but not the number of significantly dominant attributes in TDS profiles. The current findings provide insight for applications of temporal profiling to other food products and development of sodium-reduced foods with attribute profiles acceptable to consumers.

An Overview of Sensory Characterization Techniques: From Classical Descriptive Analysis to the Emergence of Novel Profiling Methods

Sensory science provides objective information about the consumer understanding of a product, the acceptance or rejection of stimuli, and the description of the emotions evoked. It is possible to answer how consumers perceive a product through discriminative and descriptive techniques. However, perception can change over time, and these fluctuations can be measured with time-intensity methods. Instrumental sensory devices and immersive techniques are gaining headway as sensory profiling techniques. The authors of this paper critically review sensory techniques from classical descriptive analysis to the emergence of novel profiling methods. Though research has been done in the creation of new sensory methods and comparison of those methods, little attention has been given to the timeline approach and its advantages and challenges. This study aimed to gather, explain, simplify, and discuss the evolution of sensory techniques.

Sensory Characterization of Iberian Dry-Cured Loins by Using Check-All-That-Apply (CATA) Analysis and Multiple-Intake Temporal Dominance of Sensations (TDS)

The aim of the present work was to sensorially characterize different commercial categories of Iberian dry-cured loins (varying genetic and feeding background) using a novel dynamic sensory technique, and to explore consumers preferences applying a rapid method. The samples (green label—GL, Cebo de Campo Ibérico; red label—RL, Bellota 50% Ibérico; and black label—BL, Bellota 100%) were analyzed by (i) Check-all-that-apply (CATA) with the evaluation of an ‘Ideal’ dry-cured loin and the overall liking, and by (ii) multiple-intake Temporal Dominance of Sensations (TDS). The CATA results indicated that the sensory characteristics of RL samples were closer to those of the ‘Ideal’ loin. Furthermore, juiciness, marbling, cured flavor, chewiness, persistence, and brightness were selected as ‘must-have’ attributes. Juiciness cured flavor and red color were considered as drivers of liking. TDS results showed that flavor attributes presented the highest dominance rates, with saltiness being the most dominant attribute along BL sample evaluation, and with cured and paprika flavor for GL and RL samples. These sensory technique results displayed the ability to sensorily characterize dry-cured loins, providing different, complementary, and valuable information.

Developing a Descriptive Sensory Characterization of Flour Tortilla Applying Flash Profile

For any food, it is important to know consumption, preference, and the characteristics as quality parameters that are important to consumers of a product. The descriptive methodologies are an important tool to know the quality attributes of the products. Within these methodologies is the flash profile (FP), which is based on the generation of the distinctive attributes of the products without any expensive and time-consuming training sessions. The aim of this research was to study the consumption and preference of flour tortillas by consumers and to develop the descriptive characterization of the tortillas by using the flash profile method. The wheat flour tortillas used were two commercial and two handcrafted samples. Ten experienced panelists participated as the FP panel. The panelists generated 22 descriptors, six for texture, seven for appearance, five for odor, and four for flavor. These descriptors differentiate the samples of the flour tortillas. The panelists’ performance was assessed using the consensus index (Rc = 0.508). The first two dimensions of the Generalized Procrustes Analysis represent 83.78% of the data variability. Flash profile proved to be an easy and rapid technique that allowed the distinctive attributes of flour tortillas to be obtained.

Sensory Analysis and Consumer Research in New Meat Products Development

This review summarises the main sensory methods (traditional techniques and the most recent ones) together with consumer research as a key part in the development of new products, particularly meat products. Different types of sensory analyses (analytical and affective), from conventional methods (Quantitative Descriptive Analysis) to new rapid sensory techniques (Check All That Apply, Napping, Flash Profile, Temporal Dominance of Sensations, etc.) have been used as crucial techniques in new product development to assess the quality and marketable feasibility of the novel products. Moreover, an important part of these new developments is analysing consumer attitudes, behaviours, and emotions, in order to understand the complex consumer–product interaction. In addition to implicit and explicit methodologies to measure consumers’ emotions, the analysis of physiological responses can also provide information of the emotional state a food product can generate. Virtual reality is being used as an instrument to take sensory analysis out of traditional booths and configure conditions that are more realistic. This review will help to better understand these techniques and to facilitate the choice of the most appropriate at the time of its application at the different stages of the new product development, particularly on meat products.

Effects of Ephedra alata extract on the quality of minced beef meat during refrigerated storage: A chemometric approach

The biopreservative effect of Ephedra alata aqueous extract (EAE), used at 0.156, 0.312 and 0.624%, on minced beef meat was evaluated by microbiological, physicochemical and sensory analyses during storage at 4 °C for 14 days. The results showed that EAE significantly (P < .05) delayed the formation of thiobarbituric acid-reactive substances and carbonyls and reduced the sulfhydryl loss in a dose-dependent manner, indicating that EAE had a protective effect against lipids and protein oxidation. Concomitantly, an increase of redness and loss of lightness and yellowness was observed. Furthermore, two multivariate exploratory techniques, namely Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were applied to all obtained data describing the main characteristics attributed to refrigerated meat samples. During storage time, the used chemometric approaches were useful in discriminating meat samples, and therefore offers an approach to underlay connections between meat quality features. The obtained findings demonstrated the strong potential of EAE as a natural preservative in meat and meat products.

Sensory Changes and Listeria monocytogenes Behavior in Sliced Cured Pork Loins during Extended Storage

Cured pork loins are sausages with a production tradition in several regions worldwide. They are made from one of the noblest cuts of pork, and for this reason cured loins are one of the most expensive pork meat products. Establishing the correct shelf life allows products to be accepted by the consumer, and to avoid the costs associated with shorter shelf lives. The aim of this study is: (1) to establish proper shelf life by evaluating the willingness of participants to consume and the sensory modifications that occur during prolonged storage via Check All That Apply (CATA) questions; and (2) to study the behavior of Listeria monocytogenes through a microbial challenge test. Sliced cured pork loins can be stored at 6 ± 1 °C for 105 days while maintaining a consumer acceptance of more than 75%. The freshness loss was associated mainly with a decrease in aromatic notes (particularly the smoke and cured aroma), and with the appearance of spoiled characteristics, specifically a sour/vinegar aroma and acidic taste that were detected by a reduced proportion of participants. The freshness evaluation was positively influenced by the typical characteristics of cured products, such as color and a garlic and wine aroma. Sour/vinegar aroma and acidic taste were the attributes most associated with higher freshness penalization. During the period of the test, Listeria monocytogenes inoculated onto the cured loin slices did not grow.

Dynamic aspects of salt reduction in tomato sauce by use of flavor enhancers and a bitter blocker

Several government agencies have established guidelines for the food industry to reduce sugar, fat, and salt in processed foods. The objective of this study was to determine the dynamic sensory profile of tomato sauce formulated with flavor enhancers, a bitter blocker and 50% sodium content reduction. The perception of consumers and a trained panel was explored. Consumers performed temporal dominance of sensations (TDS) and temporal acceptance (TA) while the trained panel performed time-intensity analysis (TI). TA indicated that flavor enhancers improve initial acceptance of a sample but that its masking effect weakens 30 s after ingestion. TI showed that despite promoting salty equivalence, substitute salts were not able to completely suppress the bitter taste characteristic of potassium chloride and the addition of lysine as a bitter blocker was the least effective strategy. In TDS the bitter taste was not dominant in any of the samples. However, the presence of unusual flavors/tastes to the consumers like metallic and umami seems to have interfered negatively in the evaluation of the flavors. Flavor enhancers have been widely used to reformulate processed foods in order to reduce sodium content, preserving sensory acceptance. This study provides information on the dynamic behavior of different salt substitutes.

Reduction of nitrate and nitrite in Iberian dry cured loins and its effects during drying process

Four batches of Iberian dry-cured loins were manufactured with reduced ingoing amounts of both nitrate and nitrite: 150 mg/kg, 75 mg/kg, 37.5 mg/kg and 0 mg/kg. The effect of reducing or removing nitrate and nitrite and time of drying on physicochemical parameters (moisture, pH, water activity, chloride and residual nitrate and nitrite contents), instrumental colour and nitrosylmyoglobin content, lipid and protein oxidation and on microbiological counts (L. monocytogenes, aerobic mesophilic bacteria and moulds and yeast counts) were investigated. Lipid oxidation increased during the drying process being higher for non-added NO₃^-/NO₂^-, meanwhile protein oxidation affected also those with 37.5 and 75 mg/kg of NO₃^-/NO₂^- added. The removal of these additives affected instrumental colour coordinates and total colour changes showing that the variation of coloration would be perceptible by the consumer. Nitrosylmyoglobin content was significantly higher for NO₃^-/NO₂^- added loins. Reduced levels of these additives up to 37.5 mg/kg did not show significant effects on their physico-chemical, microbiological and colour.

Relative contribution of sensory characteristics for different types of pork loin, assessed by temporal dominance of sensations

BACKGROUND

Sensory perception is a dynamic process occurring sequentially. The dynamic analysis of the perception of sensory characteristics in meat is important to understand complex meat sensory characteristics. Temporal dominance of sensations (TDS) is a dynamic sensory method that captures the 'dominance of sensations' throughout food consumption, and it is possible to calculate the relative contribution of various sensory characteristics by 'dominance rate' over time. The objective of this study was to assess the major sensory characteristics of the dynamic sensory perception of pork loin. Using the TDS, we evaluated pork loins derived from pigs with different genetic and feeding backgrounds. Moreover, we checked the integrity of the TDS by comparing the TDS results with a descriptive sensory analysis and a physico-chemical analysis.

RESULTS

Seven types of pork loin were evaluated by TDS, and 'tender and/or soft,' 'tough and/or hard,' 'juicy,' 'dry,' 'fat melting,' 'smoothness,' 'sourness,' 'umami,' and 'beast odors' became dominant in at least one type of pork loin. The dynamics of the perception of pork sensory characteristics was also depicted by TDS. In addition, TDS and descriptive analysis demonstrated similarity in principal component analysis.

CONCLUSION

TDS demonstrated the major sensory characteristics on the dynamic sensory perception of pork loin. © 2019 Society of Chemical Industry.