INTEGRATING SENSORY ANALYSIS AND HEDONIC EVALUATION FOR APPLE QUALITY ASSESSMENT

ABSTRACT

Apple cultivars were subjected to a consumer test in order to appreciate individual preferences and set up a protocol for a practical hedonic‐sensory evaluation. Cultivars subjected to the test were “Golden Delicious,”“Modì,”“Pink Lady” and “Fuji” of two different origins. Apples had the sensory profile defined by a trained panel and were evaluated by 154 consumers. According to their preferences, consumer population could be divided in six clusters. Consumer preference responses clearly associated the two “Fuji” and showed “Modì” and “Pink Lady” to have appeal on the same consumers groups. Besides expressing hedonic judgment, consumers were requested to indicate the positive sensory attributes determining their choice. Consumers appreciated “Golden Delicious” and “Fuji” on the basis of sweetness and aroma, while preferences for “Pink Lady” and “Modì” were expressed by consumers appreciating crispness, juiciness and a certain degree of acidity. The involvement of consumers in defining attributes driving preferences provides details useful for weighing up the consistency between consumers' response and sensory panel profile.

PRACTICAL APPLICATIONS

This work contributes to the knowledge on consumer preferences and concerning apple sensory quality. In particular, the tested varieties could be divided in three groups on the basis of perceived attributes. Knowledge of consumer preferences related to apple qualities can be a key point in planning production and marketing strategies. A protocol integrating sensory characteristics defined by a trained panel, hedonic consumer judgments and sensory preference drivers is proposed.     

Optimization Analysis of Sunflower Butter

A sunflower butter product was formulated and processing conditions were varied to study their effect on the overall sensory and physical characteristics of the final product. Amounts of salt, sugar, and stabilizer as well as roast level were optimized to yield a sunflower butter that most closely resembles peanut butter, in both physical and sensory quality. To produce a wide range of flavor, aroma, color, and texture attributes, 2 roasting levels (high and low), 2 sugar levels (7% and 9%), 2 salt levels (0.9% and 1.1%), and 3 stabilizer (Dritex‐C) levels (1.6%, 1.7%, and 1.8%) were selected. Sunflower butter formulations were rated more “earthy” and less “salty” than peanut butter, but differences in the “sweet” attribute were small. Largest differences in the textural sensory attributes were denoted for the initial firmness and spreadability, with panel judging sunflower butter samples less spreadable and having a higher initial firmness. The panel rated sunflower butters more adhesive at the 1st bite; however, once chewed, sunflower butters were rated as less adhesive and higher on the “ease of swallow”. Cluster analysis on sensory data revealed the “best” formulation to have 1.8% stabilizer, 7% sugar, 1.1% salt, and a low roast level. Cluster analysis on the instrumental hardness, adhesion, oil separation, and color profile revealed the formulation closest to the controls to have the same amount of sugar and roast level, but 1.6% of stabilizer and 0.9% salt instead.     

Training of a sensory panel and profiling of winter hardy and coloured carrot genotypes

The aim of the study was to determine the performance of a sensory panel in evaluation of carrots by investigating the effect of training sessions on the reliability of the sensory attributes. A sensory panel (n = 10) was trained in profiling five carrot genotypes during a training session with seven sensory replications and 13 attributes. A significant effect of training on the sensory profile was determined for bitterness, green flavour and burning aftertaste, indicating that a learning process in judging these attributes was taking place. Terpene flavour, terpene aroma and burning aftertaste were the most reliable determined attributes and carrot flavour, soapiness flavour and nutty flavour were the least reliable attributes. The developed sensory profile was applied on 16 carrot types with a large variation in quality. Winter hardiness, carrot genotype and carrot colour formed distinct groups within the sensory profile, which indicates that the present sensory profile is relevant for assessing sensory quality of carrots. The winter hardy genotypes were characterised by having relatively high intensities in green aroma, carrot aroma, nutty flavour, carrot flavour and sweetness, while the reverse was true for the Nantes types and the coloured carrots with the red and white genotype as being the most extreme.     

Application of near (NIR) infrared and mid (MIR) infrared spectroscopy as a rapid tool to classify extra virgin olive oil on the basis of fruity attribute intensity

A sensory analysis of 112 virgin olive oils was performed by a fully trained taste panel. The samples were divided in “defective” and “not defective” on the basis of their olfactory attributes. Then, the “not defective” samples were classified into “low”, “medium” and “high” according to the fruity aroma intensity perceived by assessors. All samples were also analysed by FT-NIR and FT-IR spectroscopy and processed by classification methods (LDA and SIMCA). The results showed that NIR and MIR spectroscopy coupled with statistical methods are an interesting technique compared with traditional sensory assessment in classifying olive oil samples on the basis of the fruity attribute. The prediction rate varied between 71.6% and 100%, as average value. The spectroscopic methods, combined with chemometric strategies, could represent a reliable, cheap and fast classification tool, able to draw a complete fingerprint of a food product, describing its intrinsic quality attributes, that include its sensory attributes.     

Influence of Visual Masking Technique on the Assessment of 2 Red Wines by Trained and Consumer Assessors

ABSTRACT:  During sensory evaluation assessments, visual masking techniques are frequently employed to disguise color differences between samples and minimize perceptual bias. Particularly in wine, the impact of these masking techniques on panelist evaluations has not been well studied. The objective of this study was to study the influence of visual masking techniques on the aroma and flavor assessment of 2 red wines and observe the impact of these techniques on trained and consumer sensory panels. Specific masking techniques included (1) blue wine glass/white illumination; (2) clear glass/red illumination; and (3) clear glass/white illumination. Ten panelists were trained to recognize 7 aroma and flavor attributes, while consumer panelists ( n = 80) evaluated attributes and liking. For the trained panel, the visual masking technique affected only perceived spicy flavor of Syrah ( P ≤ 0.05), with the clear glass/red illumination resulting in more intense spicy flavor compared to the other 2 conditions. Principal components analysis showed that for the 2 red wines evaluated by the trained panel, red illumination resulted in higher spicy attributes and perceived astringency while wines served in blue wine glasses were higher in perceived astringency. For the consumer panel, red illumination resulted in wines higher in perceived astringency and blue wine glasses resulted in wines higher in perceived flavor liking. These results indicated that the visual masking techniques may influence both trained and consumer panel evaluation of aroma and flavor attributes of red wine. However, beyond red wine, this study makes the larger point that the choice of masking technique does impact sensory evaluations.     

Sensory Quality Evaluation of Rice Using Visible and Shortwave Near-Infrared Spectroscopy

This research aimed to develop both visible and shortwave near-infrared spectroscopy to evaluate the sensory qualities of cooked rice. In this study, four different types of milled rice were used: parboiled, white, new Jasmine, and aged Jasmine. The sensory qualities of cooked rice (adhesiveness, hardness, stickiness, dryness, whiteness, and aroma) were evaluated by a trained sensory panel. The results demonstrated that these sensory attributes correlated with visible and shortwave near-infrared spectral data. Both visible and shortwave near-infrared spectroscopy models used for predicting the sensory qualities of cooked rice were established using partial least squares regression. All prediction results for sensory qualities showed a range of R²_val between 0.837 and 0.918, with the highest found for aroma (0.918). The proposed models can be utilized in quality control by the rice industry.     

Sensory Characterization of Sweet Corn Lines Differing in Physical and Chemical Composition.

Chemical, physical and sensory characteristics were determined in a population of 103 F₃ families derived from the cross between two sweet corn inbreds that differed in kernel properties associated with eating quality. Kernel characteristics correlated well with panel perception of sensory attributes. Chemical, physical and sensory properties were grouped into three factors: taste—including sweetness, starchiness, juiciness, and sucrose and starch concentrations; texture—crispness, tenderness, juiciness and cooked kernel tenderness; and aroma—sweet corn aroma, grassy aroma, grassy flavor and concentrations of an unknown volatile (V179). The relative importance in determining overall liking was taste 45.1, texture 30.5, and aroma 24.4%.     

Use of Sulfur Dioxide in Winemaking

Ten juices of common wine cultivars were studied to determine if pretreatment of the juice with air, blanketing the juice with nitrogen or pretreatment with sulfur dioxide (SO₂) was the most satisfactory method to make the better wine. Further treatment with SO₂ was made later at intervals. The pretreatment with aeration lowered the final color in the wine compared to nitrogen blanketing. SO₂ pretreatment gave the lowest colored juice for the white wines. All juices treated with SO₂ later had much lower color. Wines without SO₂ were generally less liked. Pretreatment of juice with SO₂ helped preserve good color and sensory attributes of the wines but later treatments with SO₂ were more essential in improving and maintaining quality. Oxidation was probably the most important control exercised by SO₂ additions.     

Aroma Changes in Fresh Bell Peppers (Capsicum annuum) after Hot-air Drying

The aroma of fresh and hot-air dried bell peppers (Capsicum annuum) was evaluated by sensory and instrumental methods. Hot-air drying decreased levels of the odor compounds (Z)-3-hexenal, 2-heptanone, (Z)-2-hexenal, (E)-2-hexenal, hexanol, (Z)-3-hexanol, (E)-2-hexenol, and linalool, which have green, vegetable-like, fruity, and floral notes, while intensity scores of corresponding sensory aroma attributes also decreased. The aroma of rehydrated dried samples was mainly characterized as savory, rancid/sweaty, sweet/sickly, hay-like, cacao, caramel, and nutty. Drying increased the levels of 2-methylpropanal, 2-and 3-methylbutanal, which have cacao, spicy, and rancid/sweaty odor notes; these volatiles may be correlated with the corresponding aroma attributes in the dried fruits. Principal component analysis demonstrated relationships between instrumental and sensory data for fresh samples, whereas they were more complex for dried fruits.     

Phenolic Compounds in Fresh and Dried Figs from Cilento (Italy), by Considering Breba Crop and Full Crop,in Comparison to Turkish and Greek Dried Figs

Fresh and dried figs are important components of the Mediterranean diet. In Cilento (Southern Italy), figs belonging to cultivar “Dottato” are used for the production of “PDO Cilento white figs,” as dried figs. In this article, we reported the characterization of the phenolic compounds in 19 fig samples: 9 fresh figs cultivar “Dottato” from Cilento (Italy), 10 dried fig samples from Cilento (2), Turkey (6), and Greece (2). The following phenolic compounds were identified and quantified by high‐performance liquid chromatography (HPLC)/UV‐DAD: chlorogenic acid, protocatechuic acid, vanillic acid, luteolin‐3,7‐di‐O‐glucoside, luteolin 7‐glucoside, apigenin‐7‐O‐rutinoside, rutin, quercetin‐3‐glucoside, and cyanidin‐3‐O‐rutinoside. A discriminative analysis between the peel and pulp of the samples was carried out. The 1st crop (“breba”) and the 2nd one (full crop) from Dottato figs were considered, as well as the effect of fig pollination. The majority of the phenolic compounds were predominant in the fig peel. Significant quantitative differences were found among fresh figs, whereas also some qualitative differences were obtained between fresh and dried figs from the same origin in Dottato cultivar, and among dried figs from different origins. Breba crop resulted richer in phenolics than figs of the 2nd crop. Considering the dried figs, the Turkish ones had the highest concentration in phenolic compounds. Other compounds such as the aminoacids tyrosine and tryptophan were also detected by HPLC‐DAD analysis in Dottato figs, probably due to the similarity of their chemical structure.