Sensory attributes that drive consumer acceptability of dry-cured ham and convergence with trained sensory data

The paper investigates the degree of convergence between trained panelists and consumers with regard to overall quality assessment and acceptability, respectively. In particular, the main sensory drivers used by both groups of assessors in their valuations, are investigated: first, a Principal Component Analysis (PCA) is applied to identify main dimensions underlying sensory data, and second, the external preference mapping (PREFMAP) technique, that regress consumers’ hedonic valuations on the PCA sensory dimensions, is applied. A total of eight samples of dry-cured ham was analysed by 14 trained panelists and 213 consumers in a northern city of Spain (Zaragoza). The results showed that both, consumers and trained panelists make use of the same sensory attributes to elicit their assessments, which are crumbliness, softness, flavour and sweetness. However, trained assessors are able to discriminate better the quality across ham samples, as we would expect, according to a higher degree of expertise. Interestingly, the PREFMAP technique showed a certain degree of heterogeneity in consumers’ preferences, highlighting clusters with opposite liking trends.     

Quality and shelf life assessment of Pacific white shrimp (Litopenaeus vannamei) freshly harvested and stored on ice

Pacific white shrimps (Litopenaeus vannamei) are an important shrimp aquaculture species worldwide. To quantify the quality and shelf life of untreated shrimp is imperative prior to the application of preservative treatments. In this paper, the quality and shelf life of Pacific white shrimp freshly harvested from three different farms and stored on ice for up to 12 days was investigated. The titratable acidity (TA) of shrimp specimens exhibited significant decreases (P < 0.05) whereas the metric chroma (C), total colour difference (TCD), aerobic plate count (APC), trimethylamine (TMA-N) and total volatile basic – nitrogen (TVB-N), peroxide value (PV) and p-anisidine value (AnV) exhibited significant increases during iced storage (P < 0.05). The TMA-N and TVB-N were significantly correlated whereas temporal TMA-N/TVB-N ratio increased considerably (P < 0.05). While the PV and AnV significantly correlated (P < 0.05), the temporal PV/AnV ratio depicted how primary and secondary lipid oxidation of Pacific white shrimp could relate during iced storage of 12 days. The shelf life of ice stored Pacific white shrimps was determined to be 8 days. The information gained by this study could serve as baseline for preservative treatments applied to fresh shrimps.     

Effect of freezing method and frozen storage duration on lamb sensory quality

This study assessed the effect of three freezing methods with three frozen storage durations (1, 3, and 6 months) on the sensory quality of lamb. Methods were: air blast freezer, freezing tunnel + air blast freezer, and nitrogen chamber + air blast freezer. Meat was frozen after 48 h of ageing (0-4 °C). Fresh meat (72 h ageing at 2-4 °C) was used as control. Sensory analyses (trained panel and consumer tests) were performed on loin chops (Longissimus lumborum) after 24 h of thawing. Results from the trained panel test showed that freezing (method and/or storage duration) had no significant effect. Consumers found that freezing affected sensory quality. Cluster analysis for overall acceptability divided the population into four classes with different preference patterns, and none of them showed a significant preference for fresh meat. The small differences between fresh and thawed meat shown in this study should not give consumers concerns about buying frozen meat or consuming thawed meat.     

Comparison of performance and quantitative descriptive analysis sensory profiling and its relationship to consumer liking between the artisanal cheese producers panel and the descriptive trained panel

The aim of this research was to compare the performance and sensory profiling of a panel of artisanal cheese producers against a trained panel and their relationship to consumer liking (external preference mapping). Performance was analyzed statistically at an individual level using the Fisher's test (F) for discrimination, the mean square error for repeatability, and Manhattan plots for visualizing the intra-panel homogeneity. At group level, performance was evaluated using ANOVA. External preference mapping technique was applied to determine the efficiency of each sensory profile. Results showed that the producers panel was discriminant and repetitive with a performance similar to that of the trained panel. Manhattan plots showed that the performance of artisanal cheese producers was more homogeneous than trained panelists. The correlation between sensory profiles (Rv = 0.95) demonstrated similarities in the generation and use of sensory profiles. The external preference maps generated individually with the profiles of each panel were also similar. Recruiting individuals familiar with the production of artisanal cheeses as panelists is a viable strategy for sensory characterization of artisanal cheeses within their context of origin because their results were similar to those from the trained panel and can be correlated with consumer liking data.     

Sensory analysis of lipstick

Sensory analysis of lipstick product by trained panellists started with recruiting female panels who are lipstick users, in good health condition and willing to be a part of sensory members. This group of people was further scrutinized with duo-trio method using commercial lipstick samples that are commonly used among them. About 40% of the 15 panels recruited were unable to differentiate the lipstick samples they usually use better than chance. The balance of nine panels that were corrected at least with 65% across all trials in panels screening process was formed a working group to develop sensory languages as a means of describing product similarities and differences and a scoring system. Five sessions with each session took about 90 min were carried out using 10 types of lipsticks with different waxes mixture ratio in the formulation together with six commercial lipsticks that are the most common to the panels. First session was focus on listing out the panels' perception towards the characteristic of the lipstick samples after normal application on their lips. Second session was focus on the refining and categorizing the responses gathered from the first session and translated into sensory attributes with its definition. Third session was focus on the scoring system. Fourth and fifth sessions were repetition of the third session to ensure consistency. In a collective effort of the panels, sensory attributes developed for lipstick were Spreadability, Off flavour, Hardness, Smoothness, Moist, Not messy, Glossy and Greasy. Analysis of variance was able to provide ample evidence on gauging the panel performance. A proper panels selecting and training was able to produce a reliable and sensitive trained panel for evaluating the product based on the procedures being trained.     

虾蛋白粉的制备及其分析

以虾加工下脚料为原料,利用酶法提取蛋白质,研究喷雾干燥的工艺,并对所得到的产品进行了理化分析。结果表明：采用离心喷雾干燥的条件为进风温度180℃,出风温度80℃,生产粗蛋白粉、可溶性蛋白粉的物料进料浓度分别为30％、50％;粗蛋白粉和可溶性蛋白粉中蛋白质、脂肪、灰分、水分含量分别为60．7％,15．0％,12．0％,4．9％及82．3％,0．5％,2．4％,6．3％;虾蛋白粉中必需氨基酸含量较高,占氨基酸总量的41．29％,牛磺酸含量0．280％。     

The use of a tea polyphenol dip to extend the shelf life of silver carp (Hypophthalmicthys molitrix) during storage in ice

The effects of a tea polyphenols (TP) dip treatment on quality changes of silver carp (Hypophthalmicthys molitrix) during iced storage were examined over a period of 35 days. TP (0.2%, w/v) solution was used for the dip treatment. The control and the treated fish samples were analysed periodically for microbiological (total viable count), chemical (pH, TVB-N, TBA, K-value), and sensory characteristics. The results indicated that the effect of the TP dip treatment on the fish samples was to enable the good quality characteristics to be retained for longer and to extend the shelf life during the iced storage.     

Evaluation of chitosan nanoparticles as a glazing material for cryogenically frozen shrimp

The potential of chitosan (CH) combined with sodium tripolyphosphate (TPP) nanoparticles as a glazing material for shrimp was investigated. Two CH–TPP nanoparticles glazing solutions were prepared: (1). A solution containing CH–TPP nanoparticles with 0.25 (g/100 mL) CH and 0.083 (g/100 mL) TPP (25CH–TPP) and (2). A solution containing CH–TPP nanoparticles with 0.5 (g/100 mL) CH and 0.167 (g/100 mL) TPP (50CH–TPP). Frozen shrimp samples were glazed with 25CH–TPP, 50CH–TPP, CH, TPP, acetic acid, and/or distilled water and then stored at −21 °C for 30 days. Glazed and non-glazed shrimp (NG) samples were analyzed for moisture content, glazing yield, weight loss, color, cutting force, thiobarbituric acid reactive substances (TBARS), yeasts, molds, coliforms and aerobic counts after 1, 3, 5, 20, and 30 d storage. Triplicate experiments were conducted and data statistically analyzed (α = 0.05). Glazed shrimp had higher moisture than NG after 30 d storage. Among the glazes, 25CH–TPP and 50CH–TPP were the most effective in controlling lipid oxidation and reducing aerobic counts and yeasts and molds in shrimp.     

Sensory characteristics of spoilage and volatile compounds associated with bacteria isolated from cooked and peeled tropical shrimps using SPME-GC-MS analysis

The spoilage potential of six bacterial species isolated from cooked and peeled tropical shrimps (Brochothrix thermosphacta, Serratia liquefaciens-like, Carnobacterium maltaromaticum, Carnobacterium divergens, Carnobacterium alterfunditum-like and Vagococcus penaei sp. nov.) was evaluated. The bacteria were inoculated into shrimps, packaged in a modified atmosphere and stored for 27 days at 8 °C. Twice a week, microbial growth, as well as chemical and sensory changes, were monitored during the storage period. The bacteria mainly involved in shrimp spoilage were B. thermosphacta, S. liquefaciens-like and C. maltaromaticum whose main characteristic odours were cheese-sour, cabbage-amine and cheese-sour-butter, respectively. The volatile fraction of the inoculated shrimp samples was analysed by solid-phase microextraction (SPME) and gas chromatography coupled to mass spectrometry (GC-MS). This method showed that the characteristic odours were most likely induced by the production of volatile compounds such as 3-methyl-1-butanal, 2,3-butanedione, 2-methyl-1-butanal, 2,3-heptanedione and trimethylamine.     

Comparison between the Arrhenius model and the radial basis function neural network (RBFNN) model for predicting quality changes of frozen shrimp (Solenocera melantho)

Changes in quality indices [total volatile base nitrogen (TVB-N), salt extractable protein (SEP), hypoxanthine (Hx), K-value, sensory assessment (SA), and electrical conductivity (EC)] for shrimp (Solenocera melantho) stored at ?28, ?20, and ?12°C for 112 days were investigated in this study. The Arrhenius model and the radial basis function neural network (RBFNN) model were established to predict changes in the quality of shrimp during storage. Quality of shrimp stored at ?12°C changed more quickly during 56–112 days, but those stored at ?28°C deteriorated slowly during the entire storage period. Additionally, the indicators SEP, EC, and SA all fitted to the Arrhenius model well (relative errors within ±10%), but this model did not perform well in the prediction of K-value, Hx, and TVB-N on some days. However, the RBFNN model showed excellent accuracy for all indicators (relative errors within ±0.5%). The RBFNN model performed better than the Arrhenius model in predicting the quality of shrimp stored at ?28°C to ?12°C.     

Identification of hemocyanin as a novel non-cross-reactive allergen from the giant freshwater shrimp Macrobrachium rosenbergii

Scope : Sensitization to giant freshwater shrimp Macrobrachium rosenbergii (Mr) was recently reported. However, the allergens have yet to be identified. This study aimed to identify and characterize a novel allergen of Mr shrimp. Methods and results: Extracted proteins were separated and purified by anion and in some experiments, size‐exclusion chromatography. Serum IgE from shrimp allergic donors identified a candidate protein, which was characterized by LC‐MS/MS. The specificity of IgE binding was tested using immunoblotting and inhibition ELISA. The IgE‐binding profiles from 12 of 13 Mr allergic subjects that were pre‐incubated with an extract of Penaeus monodon showed residual binding to ～60–80 kDa proteins. The 60–80 kDa IgE‐bound proteins were fractionated in the flow‐through of anion chromatography showing a high IgE reactivity. Peptides identified by LC‐MS/MS showed the proteins closely match subunits of hemocyanin (Hcs). Purified Hcs from hemolymph markedly inhibited binding of IgE from sera of Mr allergic subjects to solid‐phased Mr proteins in inhibition ELISA. Conclusion: Hcs were identified as heat‐stable, non‐cross‐reactive, high‐molecular‐weight (MW) allergens from Mr shrimp. Since circulatory organs are not always removed during food preparation, high concentrations of Hcs may be present along with shrimp meat, which contains the known cross‐reactive tropomyosin protein.     

Investigation of quality attributes of ice-stored Pacific white shrimp (Litopenaeus vannamei) as affected by sequential minimal ozone treatment

Ozone treatment is among non-thermal technologies with great promise to the seafood industry. Additionally, the demand for high quality minimally processed food products is increasing worldwide. However, no research endeavors has explored the quality attributes of sequential minimal ozone-treated ice stored shrimp. Therefore, the present investigation was undertaken to study the quality attributes of ice-stored Pacific white shrimp subject to minimal ozone treatment sequentially applied at days 1, 3, 5, 8 and 11. Quality indicators measured include aerobic plate count (APC), titratable acidity (TA), metric chroma, hue difference (ΔH), total colour difference (TCD), trimethylamine-nitrogen (TMA-N), total volatile basic-nitrogen (TVB-N), peroxide value (PV), p-anisidine value (AnV) and total oxidation (totox). The results indicated that the TA, metric chroma, ΔH, TCD, APC, TMA-N, TVB-N, PV, AnV and Totox values changed significantly with storage. Also, statistical differences in correlations and temporal rates of TMA-N and TVB-N as well as PV and AnV of sequential minimal ozone-treated ice-stored shrimp were obtained compared to control (P < 0.05). The noticeable reductions in APC, TMA-N, TVB-N and PV showed sequential minimal ozone treatment to resemble an anti-oxidant and thus, could within the respective limits of acceptability promise the safety of shrimp for consumption.     

Correlations of trained panel sensory values of cooked pork with fatty acid composition,muscle fiber type,and pork quality characteristics in Berkshire pigs

The objective was to examine the relationship of trained panel sensory scores of cooked pork with fatty acid composition, muscle fiber type, and meat quality characteristics from Berkshire pigs. No or few associations were found between the panel sensory scores of cooked meat, especially tenderness attributes, and fatty acid composition; however, intramuscular fat content positively correlated with off-flavor score (r = 0.31). On the other hand, the morphological characteristics of muscle fibers were correlated with panel sensory values. Muscles with smaller cross-sectional area and higher density of fibers were more closely associated with softer, more tender panel scores and a lower number of chews than muscles with larger fiber area and lower density of fibers. The water holding capacity test of filter-paper fluid uptake was moderately correlated with panel scores of softness (r = 0.33), initial tenderness (r = 0.38), chewiness (r = 0.40), juiciness (r = − 0.27), flavor intensity (r = − 0.23), and off-flavor (r = 0.30). Panel sensory values of Berkshire pig meat was moderately related to postmortem meat quality, especially water holding capacity. A more thorough understanding of the relationships between fatty acid composition and muscle fiber type with palatability is needed.     

Sensory and quality parameters of raw and processed Chicory-Hindbeh,a commonly consumed dark leafy green in Lebanon (Cichorium intybus L.) during frozen storage

This work aimed at assessing the effect of heat treatment and frozen storage on the sensory and chemical properties of chicory with the goal of optimizing the heat pretreatment-storage condition to best preserve the chemical and sensory properties of chicory. Raw, boiled (10 min), blanched (90 °C for 60 s) and steamed (for 20 s) chicory samples were produced and stored at −6 °C, −12 °C or −18 °C for 4 months. Chemical analyses (moisture, ash, vitamin C, peroxidase activity, chlorophyll and color) and sensory evaluation (QDA and hedonic evaluation) were conducted. Treatment significantly influenced all chemical variables (p < 0.001), except for moisture; and so did freezing temperatures for a-value (p < 0.001), chlorophyll-a, peroxidase activity, vitamin C and ash (p < 0.01), total chlorophyll, moisture and b-value (p < 0.05). Differences were obtained for age for all chemical variables (p < 0.001). Treatments affected consumers' acceptability of chicory and QDA showed that boiled chicory was significantly more tender, less chewy and crunchy and needed less time to disintegrate than other samples. PCA showed that PC1 and PC2 separated attributes based on type and intensity of treatments, respectively. It is recommended to use blanching at 90 °C for 60 s and freezing at −12 °C or −18 °C to best preserve the quality of chicory.     

Detection of low frequency external electronic identification devices using commercial panel readers

The ability of a commercially available panel reader system to read International Standards Organization-compliant electronic identification devices under commercial dairy conditions was examined. Full duplex (FDX-B) and half-duplex (HDX) low frequency radio-frequency identification external ear tags were utilized. The study involved 498 Holstein cows in the final 6 wk of gestation. There were 516 total electronic identification devices (n = 334 HDX and n = 182 FDX-B). Eighteen FDX-B were replaced with HDX during the study due to repeated detection failure. There were 6,679 HDX and 3,401 FDX-B device detection attempts. There were 220 (2.2%) unsuccessful and 9,860 (97.8%) successful identification detection attempts. There were 9 unsuccessful detection attempts for HDX (6,670/6,679 = 99.9% successful detection attempts) and 211 unsuccessful detection attempts for FDX-B (3,190/3,401 = 93.8% successful detection attempts). These results demonstrate that this panel system can achieve high detection rates of HDX devices and meet the needs of the most demanding management applications. The FDX-B detection rate was not sufficient for the most demanding applications, requiring a high degree of detection by panel readers. The lower FDX-B rate may not be inherent in the device technology itself, but could be due to other factors, including the particular panel reader utilized or the tuning of the panel reader.