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Selected AbstractsPerceptual interactions between fruity and woody notes of wineFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2004Boriana Atanasova Abstract The quantitative olfactory interactions in three binary mixtures of wine aroma compounds were studied. For the ,rst two mixtures, whisky lactone (woody note) was mixed separately with two esters (fruity note), ethyl butyrate and isoamyl acetate. For the third mixture, guaiacol (woody note) was mixed with ethyl butyrate (fruity note). Perceived odour intensity of 24 stimuli (four supra-threshold concentration levels of two compounds and the respective 16 mixtures) were evaluated in ,ve replications, by a trained panel of 13 subjects. The results showed that for the three binary mixtures studied, quantitative perceptual interactions were non-level independent, non-symmetrical, and reached the compromise level of hypo-addition. The experimental data highlighted that generally mixtures with high whisky lactone levels led to the compromise level of mixture intensity perception, whereas mixtures with high fruity note intensity proportions did not. A tendency to hyper-addition was observed in iso-intense mixtures only at the lowest intensity level. Copyright © 2004 John Wiley & Sons, Ltd. [source] PHYSICO-CHEMICAL ANALYSES, SENSORY EVALUATION AND POTENTIAL OF MINIMAL PROCESSING OF PEJIBAYE (BACTRIS GASIPAES) COMPARED TO MASCARENES PALMSJOURNAL OF FOOD QUALITY, Issue 2010J. JOAS ABSTRACT A palm species native of South America, pejibaye (Bactris gasipaes), was recently introduced in Reunion Island in an attempt to diversify its agriculture. Morphological analyses highlighted the agronomic advantages of pejibaye including a high weight-to-harvest-date ratio compared to three mascarenes palm species. Sensory analyses by a trained panel allowed the elaboration of sensory profiles of the four palms tested. Ranking test done by 120 consumers revealed that pejibaye was preferred to the Mascarenes palms at the 5% level of significance and triangle test showed that Acanthophoenix rubra (red palm), the most cultivated species for the local market, was significantly different from pejibaje at the 1% level. Phenolic profiles revealed that pejibaye differed from the other species by a peak absorbing at 272 nm and weak polyphenol oxidase activities. As no browning reaction was observed in fresh cut pejibaye, this palm could be used for minimal processing (local and export market). PRACTICAL APPLICATIONS Sensorial characteristics of fresh hearts of palm are different of those of canned heart of palm, and fresh heart palms are generally preferred by consumers. However, the marketing of fresh palm is limited by the high level of oxidation of most of palm species. The high stability of pejibaye after cutting and its slow rate of oxidation offer the possibility of minimal processing, without special additives. So the packaging in wrapped trays of this palm, cut and stored at low temperature opens up new perspectives, ensuring sensorial quality of a "fresh" product with a shelf life allowing a controlled management of market supply. [source] EFFECTS OF COOKING METHODS ON SENSORY QUALITIES AND CAROTENOID RETENTION IN SELECTED VEGETABLES,JOURNAL OF FOOD QUALITY, Issue 5 2006MONIQUE D. NUNN ABSTRACT The effects of induction boiling, conventional boiling and microwave steaming on the sensory qualities and carotenoid retention of broccoli, carrots, green beans and sweet potatoes were investigated. Significantly higher cooking yields were obtained for vegetables that were induction and conventionally boiled. No differences in the retentions of alpha-carotene (, -carotene), beta-carotene (, -carotene) and lutein/zeaxanthin were observed for vegetables by the cooking method, with the exception of , -carotene retention in broccoli and sweet potatoes where retentions were higher for those that were induction boiled (90.3 and 86.1%, respectively) than those that were microwave steamed (62.2 and 66.4%, respectively). A trained panel judged the color scores of three vegetables by the cooking method as similar. The mean flavor scores (1 = extremely bland; 9 = extremely intense) for three vegetables that were conventional (4.7,5.4) and induction (5.3,5.5) boiled were lower than those that were microwave steamed (5.9,7.0). The mean texture scores (1 = extremely mushy/tender; 9 = extremely firm/tough) for all induction-boiled (5.0,6.0) vegetables were higher than those that were conventionally boiled (3.4,5.2) and lower than those that were microwave steamed (5.1,6.6). [source] Relation between Developmental Stage, Sensory Properties, and Volatile Content of Organically and Conventionally Grown Pac Choi (Brassica rapa,var.JOURNAL OF FOOD SCIENCE, Issue 4 2010Mei Qing Choi) ABSTRACT:, This study was conducted to identify and quantify the sensory characteristics and chemical profile of organically and conventionally grown pac choi (Brassica rapa,var. Mei Qing Choi), also called bok choy, at 3 stages of growth (2.5, 4.5, and 6.5 wk). Sensory and instrumental data were correlated using partial least squares regression. Pac choi was grown in late spring. Descriptive sensory analysis was conducted by a highly trained panel and compounds were identified and quantified using a gas chromatograph/mass spectrometer. The findings of the study indicate that the differences in sensory characteristics and chemical profiles among stages of growth are more substantial than the differences between organic and conventional production. Green-unripe, musty/earthy, lettuce, and sweet flavors are representative in pac choi at early stages of growth. When older, pac choi has higher intensities of green-grassy/leafy, bitter, cabbage, and sulfur flavors that are associated with the increase of (Z)-3-hexen-1-ol, octyl acetate, 1-nonanol, 2-decanone, 1-penten-3-ol, linalool, camphor, menthol, isobornyl acetate, geranylacetone, and cedrol compounds. Conventional pac choi was higher than organic pac choi in green overall, bitter, and soapy flavors only at 2.5 wk of age. This may be associated with the presence of (Z)-3-hexenal, 2-hexyn-1-ol, and (E)-2-hexenal compounds. Practical Application: The increased popularity of organic production has amplified the need for research that will help in understanding how this production system affects the final quality of food products. This study suggests that the stage of development has a much larger impact on sensory quality than organic or conventional growing of pac choi. Findings from this study promote consumer choice by showing that comparable sensory quality can be obtained using either production system, making the ultimate choice not only based on sensory quality but consumer choice related to environmental beliefs or economics. [source] Assignation of Sweet Cherry Selections to 3 Taste Groupings Based on Perceived Sweetness and SournessJOURNAL OF FOOD SCIENCE, Issue 1 2010Carolyn F. Ross ABSTRACT:, Providing consumers with basic taste properties of sweet cherries at point of purchase would allow consumers to make purchase decisions based on fruit's intrinsic sensory attributes. The objective of this study was to develop a model to predict taste-grouping assignation of cherries into the following categories: (1) low sweetness/high sourness, (2) balance between sweetness and sourness, and (3) high sweetness/low sourness. A sensory panel (n,= 10) was trained to recognize sweetness and sourness in 5 cultivars of sweet cherries and assign a taste grouping based on the perceived balance of sweetness and sourness. Four of these same cultivars were then evaluated for sweetness and sourness by a consumer panel (n,= 117) and instrumentally for titratable acidity (TA) and soluble solids concentration (SSC). Results showed that for 3 of the 4 cherry cultivars, the sweetness/sourness balance of the cherries was not significantly different as evaluated instrumentally or by the trained panel. However, the balance determined by the consumer and the trained panel was different for 3 of the 4 cherry cultivars (P,< 0.05). Based on trained panel perceived sweetness and sourness, a multinomial logit model was developed to predict the assignation of cherry taste grouping. The likelihood of group assignment depended on both the perceived sweetness and sourness of the cherry, with taste groupings agreed upon for 3 of 5 sweet cherry cultivars. As previous studies have indicated a positive relationship between cherry sweetness and sourness to consumer acceptance, these groupings show promise for assisting consumers in cherry selection at the point of purchase. Practical Applications: The prediction models proposed in this study suggest that both sweetness and sourness are important in the cherry characterization and the ratio between the 2 attributes may be appropriate for making taste-grouping assignments. These groupings may then be used to provide additional sensory information to consumers to assist them in cherry selection at the point of purchase. [source] Controlling Light Oxidation Flavor in Milk by Blocking Riboflavin Excitation Wavelengths by InterferenceJOURNAL OF FOOD SCIENCE, Issue 9 2009J.B. Webster ABSTRACT:, Milk packaged in glass bottles overwrapped with iridescent films (treatments blocked either a single visible riboflavin [Rb] excitation wavelength or all visible Rb excitation wavelengths; all treatments blocked UV Rb excitation wavelengths) was exposed to fluorescent lighting at 4 °C for up to 21 d and evaluated for light-oxidized flavor. Controls consisted of bottles with no overwrap (light-exposed treatment; represents the light barrier properties of the glass packaging) and bottles overwrapped with aluminum foil (light-protected treatment). A balanced incomplete block multi-sample difference test, using a ranking system and a trained panel, was used for evaluation of light oxidation flavor intensity. Volatiles were evaluated by gas chromatography and Rb degradation was evaluated by fluorescence spectroscopy. Packaging overwraps limited production of light oxidation flavor over time but not to the same degree as the complete light block. Blocking all visible and UV Rb excitation wavelengths reduced light oxidation flavor better than blocking only a single visible excitation wavelength plus all UV excitation wavelengths. Rb degraded over time in all treatments except the light-protected control treatment and only minor differences in the amount of degradation among treatments was observed. Hexanal production was significantly higher in the light-exposed control treatment compared to the light-protected control treatment from day 7; it was only sporadically significantly higher in the 570 nm and 400 nm block treatments. Pentanal, heptanal, and an unidentified volatile compound also increased in concentration over time, but there were no significant differences in concentration among the packaging overwrap treatments for these compounds. [source] Effect of Oxygen-Absorbing Packaging on the Shelf Life of a Liquid-Based Component of Military Operational RationsJOURNAL OF FOOD SCIENCE, Issue 4 2009Carmen Gomes ABSTRACT:, Oxygen within the sealed package can reduce the quality of liquid-based food products with high oil content such as hot-filled meal-ready-to-eat (MRE) cheese spread, a component of military operational rations. The aim of this study was to test a novel oxygen absorber-containing laminate material and its ability to maintain and/or extend shelf life of a cheese-spread MRE item. An iron-based oxygen absorber (ABSO2RB®) activated by moisture was incorporated into the laminate and used to pack hot-filled cheese spread MREs. The kinetics of oxygen absorption due to humidity and temperature were characterized and peel tests performed to ensure pouch seal integrity. Accelerated shelf-life tests of ABSO2RB and regular MRE pouches without the O2 -absorber were conducted for 3 mo at 51.7 °C (125 °F), and 6 mo at 37.8 °C (100 °F) by measuring oxygen concentration (Mocon O2 -analyzer), microbiological, and physicochemical quality characteristics, including color, texture, moisture, free fatty acid (FFA), pH, water activity, and vitamins and A. Pouches stored at 26.7 °C (80 °F) for 12 mo served as calibrated controls. Consumer tests were conducted in-house and a confirmatory sensory test was conducted at Natick by a trained panel using a 9-point hedonic scale. ABSO2RB-laminates maintain the same seal integrity and strength as those of the control samples. The headspace oxygen concentrations in these pouches reached (P < 0.05) < 0.5% in 11 d of storage at 26.7 °C (80 °F) and remained below this level throughout the storage period (1 y). No microbial growth (aerobic, coliforms, yeast, and molds) was detected (P < 0.05) for both packages. Overall, the ABSO2RB-pouches indicate an improved reduction in oxygen and vitamin C retention compared with MRE controls and maintained product quality (physicochemical and organoleptic). ABSO2RB-laminates met the accelerated shelf-life requirement of 1 mo at 51.7 °C (125 °F), and 6 mo at 37.8 °C (100 °F). This study clearly shows the benefits of using active packaging technology on retaining nutrition and prolonging shelf life of high-fat, liquid content MRE items. [source] Influence of Visual Masking Technique on the Assessment of 2 Red Wines by Trained and Consumer AssessorsJOURNAL OF FOOD SCIENCE, Issue 6 2008C.F. Ross 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. [source] Characterization of Aroma-Active Compounds in Microwave Blanched PeanutsJOURNAL OF FOOD SCIENCE, Issue 9 2006A.V. Schirack ABSTRACT:, Microwave blanching of peanuts has been explored as an alternative to conventional oven methods based on its speed of operation, energy savings, and efficiency of process control. Although processing times can be greatly reduced, the occurrence of stale/floral and ashy off-flavors has been reported at high process temperatures. This study examined the chemical compounds responsible for this off-flavor using solvent extraction/solvent assisted flavor evaporation (SAFE), gas chromatography-olfactometry (GC/O), gas chromatography-mass spectrometry (GC/MS), and aroma extract dilution analysis (AEDA). Select compounds were quantified based on AEDA results using SAFE and GC/MS. Quantification, threshold testing, and analysis of model systems revealed increased formation of guaiacol and phenylacetaldehyde in the off-flavored peanuts, which resulted in the burnt and stale/floral flavors noted by a trained panel. [source] Evaluation of Garam Masala Spices and Phosphates as Antioxidants in Cooked Ground BeefJOURNAL OF FOOD SCIENCE, Issue 5 2006Mihir N. Vasavada ABSTRACT:, This study determined antioxidant effects and sensory attributes of individual ingredients (black pepper, caraway, cardamom, chili powder, cinnamon, cloves, coriander, cumin, fennel, ginger, nutmeg, salt, star anise) of an Indian spice blend (garam masala) in cooked ground beef. Thiobarbituric acid (TBA) values were measured as an indicator of rancidity for cooked samples on 1-, 8-, or 15-d refrigerated storage. Cooked samples were evaluated by a trained panel (n= 13) for the intensity of rancid odor/flavor, beef flavor, and spice flavor and correlated with TBA values of same day samples. We also investigated possible additive effects between spice antioxidants and iron binding (type II) antioxidants on lipid oxidation by measuring TBA values. All spices had antioxidant effects on cooked ground beef, compared to controls. Among spices, cloves were the most effective in controlling lipid oxidation, with TBA values of 0.75, after 15-d refrigerated storage. All spices at their recommended levels lowered rancid odor and flavor in cooked ground beef, compared to controls. As expected, most spices also imparted distinctive flavors to cooked ground beef. There was a positive correlation (0.77) between TBA values on 15-d refrigerated storage and rancid odor/flavor. Type II antioxidants (iron-binding phosphate compounds) were more effective than individual type I antioxidants (spices and butylated hydroxytoluene; BHT) for maintenance of low TBA values in cooked ground beef during storage. Additive effects were observed with rosemary + milk mineral or sodium tripolyphosphate (STP) compared to rosemary alone. [source] Evaluation of Antioxidant Effects of Raisin Paste in Cooked Ground Beef, Pork, and ChickenJOURNAL OF FOOD SCIENCE, Issue 4 2006M.N. Vasavada ABSTRACT:, The objective of this study was to evaluate the possible antioxidant activity of raisin paste added to raw ground beef, pork, or chicken before cooking to 163 °C. Samples were held at 2 °C for up to 14 d. TBA values were measured using a distillation method, to avoid yellow color interference found in "wet" TBA methods. Sample meat flavor intensity, rancid flavor intensity, and raisin flavor intensity were evaluated by a trained panel (n = 6). Addition of raisin paste lowered (p < 0.05) TBA values and decreased panel scores for rancid flavor scores of all meat samples in a concentration-dependent manner. Highest antioxidant effects were obtained with a minimum of 1.5%, 2.0%, or 2.0% raisin paste in cooked ground beef, pork, or chicken, respectively. There was a high correlation (0.93, 0.94, 0.94) between TBA values and sensory rancid flavor scores in beef, pork, and chicken samples respectively. Addition of a reducing sugar (glucose) was nearly as effective as raisins for maintenance of low TBA values and rancid flavor scores, probably due to antioxidant effects of Maillard browning products. There was no detectable raisin flavor in cooked ground beef samples with added raisins. However, all meats with added glucose had a higher raisin flavor intensity score than controls, indicating that panelists associated sweetness with raisin flavor. Maillard browning (sample darkening) was evident after cooking of ground chicken with either raisins or glucose. [source] Characterization of a Cabbage Off-flavor in Whey Protein IsolateJOURNAL OF FOOD SCIENCE, Issue 2 2006Joy M. Wright ABSTRACT Whey protein isolate (WPI) is a value-added protein with multiple ingredient applications. A bland flavor is expected in WPI, and off-flavors can limit its use in foods. Recently, a cabbage off-flavor was noted in some WPI. The objective of this study was to characterize the source of cabbage flavor in WPI. WPI with and without cabbage flavor were collected, and descriptive sensory analysis was conducted on the rehydrated WPI using a trained panel and a previously identified sensory language. Volatile compounds were extracted by solvent extraction followed by solvent-assisted flavor evaporation (SAFE), followed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GCO), to identify and characterize aroma-active compounds. Dimethyl trisulfide (DMTS) (cabbage aroma) was identified by GCO and GC-MS in WPI with the cabbage flavor. DMTS was quantified by solid-phase microextraction (SPME) with GC-MS. Orthonasal thresholds of DMTS in deodorized water and WPI were determined by ascending forced choice analysis, and descriptive analysis of model systems was used to confirm instrumental results. DMTS levels were 1.94 ± 0.26 and 3.25 ± 0.61 parts per billion (ppb) in WPI with cabbage flavor, and 0.44 ± 0.25 and 0.43 ± 0.18 ppb in those without cabbage flavor. The orthonasal thresholds for DMTS in water and WPI were 0.07 ± 1.28 parts per trillion (ppt) and 0.80 ± 0.45 ppb, respectively. Descriptive analysis of model systems confirmed the role of DMTS in the cabbage off-flavor. Knowledge of the source of this flavor will aid in identification of ways to minimize or prevent DMTS formation in WPI. [source] Perception of Bread: A Comparison of Consumers and Trained AssessorsJOURNAL OF FOOD SCIENCE, Issue 2 2005Margrethe Hersleth ABSTRACT: The main objective of this study was to investigate consumers' perception of bread and to compare the used vocabulary with descriptive attributes used by a trained panel. Perceived appropriateness of breads were also studied and related to the sensory perception. Seven different types of bread were chosen for the study. The breads were presented to 30 consumers, and the repertory grid method was used to obtain information about sensory perception and appropriateness of use. The breads were also presented to a trained sensory panel performing sensory profiling. Multivariate analyses of the data showed that the latent structure in consumers' perception of a selection of breads was similar to the latent structure in a trained panel's perception of the same breads. For verbal description of the texture, the 2 panels used many identical words. Moreover, multivariate analyses revealed the relationship between consumers' perception of the breads and the appropriateness of use. [source] SENSORY DESCRIPTIVE ANALYSIS, SENSORY ACCEPTABILITY AND EXPECTATION STUDIES ON BISCUITS WITH REDUCED ADDED SALT AND INCREASED FIBERJOURNAL OF SENSORY STUDIES, Issue 4 2009MARISA BEATRIZ VÁZQUEZ ABSTRACT The aims of this study were to formulate biscuits with 50% more fiber and 50% less added salt than classic formulations, to describe their sensory characteristics, to measure expectation/sensory acceptability, and to investigate if sensory acceptability for these biscuits was related to the interest in consuming food products with less salt and/or more fiber content. A 2 × 2 factorial design was used to develop four formulations: conventional fiber/conventional salt; conventional fiber/reduced salt; increased fiber/conventional salt; and increased fiber/reduced salt. Differences in the sensory profiles measured by a trained panel were of low magnitude, except for presence and taste of bran. Adolescent and adult consumers evaluated acceptability in three stages: blind with three-digit codes; expectation of the label only; and biscuit + label. The low salt formulations received the lowest scores in the expectation stage, but in the blind and biscuit + label stages acceptability of all formulations was similar. The variables that explained overall acceptance were: measurement stage; formulation salt level; interest in reducing consumption of high salt foods; and interest in consuming bakery products with fiber. PRACTICAL APPLICATIONS Increasing fiber content of biscuits by 40 to 50% helps achieve recommendations to increase fiber intake in daily diets. Also, as biscuits currently on the Argentine and other world markets present two extreme varieties , with or without added salt , formulating a biscuit with 50% less added salt facilitate sodium reduction. In our research we have found that these goals can be achieved without seriously affecting sensory acceptability. We propose the articulation of the necessary strategies with the food industry to market biscuits with less added salt and more fiber for the general population; and the use of these healthier biscuits by institutional food services. [source] EFFECTS OF BITE SIZE ON THE SENSORY PROPERTIES OF VANILLA CUSTARD DESSERTSJOURNAL OF SENSORY STUDIES, Issue 3 2007JON F. PRINZ ABSTRACT A trained panel of 19 subjects were asked to rate a number of sensory attributes of commercially available vanilla custard desserts. Stimuli were placed in plastic cups and were sampled using 11-mm-diameter straws. In total, 304 samples were weighed before and after sampling and the volume ingested was calculated. The subjects were categorized into two groups on the basis of the mean volume ingested per sample (< and >10.6 mL). There were significant differences in the ratings between the two groups for temperature, creamy, astringent, melting and airy mouthfeels and rough and fatty after-feel. We suggest that in sensory testing, it is important to either control or measure bite size to reduce intersubject variability. Manufacturers and caterers may also be able to modify the perception of their products by providing cues to the appropriate bite size by controlling the size of the spoon or container provided. [source] IMPACT OF DRYING AND STORAGE TIME ON SENSORY CHARACTERISTICS OF ROSEMARY (ROSMARINUS OFFICINALIS L.)JOURNAL OF SENSORY STUDIES, Issue 1 2007M.C. DÍAZ-MAROTO ABSTRACT The effect of drying treatment on the aroma characteristics of rosemary (Rosmarinus Officinalis L.) was studied using the Quantitative Descriptive Analysis (QDA) with a trained panel and by Free Choice Profiling (FCP) analysis with a consumer group. Differences between samples were observed after applying Principal Component Analysis to the QDA data and Generalized Procrustes Analysis to the FCP data. The highest differences were found between fresh rosemary samples and dried samples. However, dried samples (obtained by oven-drying at 45C and commercial samples purchased at the markets and stored for 6 months) showed significant differences in their sensory characteristics. Odor detection thresholds of the fresh rosemary leaves were calculated in water and in potato sauce, and significant differences were found. [source] ESTIMATION OF HEDONIC RESPONSES FROM DESCRIPTIVE SKIN SENSORY DATA BY CHI-SQUARE MINIMIZATIONJOURNAL OF SENSORY STUDIES, Issue 1 2006I.F. ALMEIDA ABSTRACT Six topical formulations were evaluated by a trained panel according to a descriptive analysis methodology and by a group of consumers who rated the products on a hedonic scale. We present a new approach that describes the categorical appreciation of appearance, texture and skinfeel of the formulations by the consumers as a function of related sensory attributes assessed by the trained panel. For each hedonic attribute, a latent random variable depending on the sensory attributes is constructed and made discrete (in a nonlinear fashion) according to the distribution of consumer-hedonic scores in such a way as to minimize a corresponding chi-square criterion. Standard partial least squares (PLS) regression, bootstrapping and cross-validation techniques describing the overall liking of the hedonic attributes as a function of associated sensory attributes were also applied. Results from both methods were compared, and it was concluded that chi-square minimization can work as a complementary method to the PLS regression. [source] SENSORY SHELF-LIFE ESTIMATION OF ALFAJOR BY SURVIVAL ANALYSISJOURNAL OF SENSORY STUDIES, Issue 6 2004ADRIANA GÁMBARO ABSTRACT Survival analysis methodology was used to estimate the shelf life of alfajor (a chocolate-coated individually wrapped cake) at 20 and 35C by using results obtained from consumers when asked if they would accept or reject samples with different storage times. Sensory acceptability (measured by consumers), off-flavor (measured by a trained panel) and moisture content were linearly related to time. These correlations were used to estimate values at the shelf-life times calculated for 25 and 50% rejection probability. Survival analysis provided the following shelf-life estimation: 74 days at 20C and 33 days at 35C for a 25% of rejection, 87 days at 20C and 39 days at 35C for a 50% of rejection. An alfajor stored at 20C having an acceptability value below 4.9 (1,9 hedonic scale) and off-flavor intensity above 5.3 (0,10 scale) would be rejected by 25% of the consumers. Chemical data were not good shelf-life predictors. [source] EFFECTS OF SAMPLING CONDITIONS ON TEMPORAL PERCEPTION OF BITTERNESS IN YERBA MATE (ILEX PARAGUARIENSIS) INFUSIONSJOURNAL OF SENSORY STUDIES, Issue 3 2004AMALIA CALVIÑO ABSTRACT Time-intensity (TI) methodology and a trained panel were used to characterize the perceived bitterness of Yerba mate (YM) Ilex paraguariensis infusions. Two sampling procedures (sip and spit; sip and swallow) and two conditions for residence time in mouth (free or fixed duration of 5 s until spit or swallow) were evaluated. At a fixed duration the maximum bitterness as well as the time to reach it showed a significant YM concentration dependence. No change on bitterness was observed by swallowing or spitting YM infusions except a larger rate of decay of the response (vr) at spit condition. Dynamic bitterness at free sampling time showed that the decision period to spit or swallow the YM infusion approximately duplicated the fixed one of 5 s. [source] EVALUATION OF THE CHARACTER IMPACT ODORANTS IN SKIM MILK POWDER BY SENSORY STUDIES ON MODEL MIXTURESJOURNAL OF SENSORY STUDIES, Issue 1 2004Y. KARAGÜL-YÜCEER ABSTRACT The objective of this study was to verify key aroma-active compounds responsible for reconstituted fresh skim milk powder (SMP) aroma using threshold analysis, odor activity values, and model systems. Twelve odor-active compounds of SMP and one odor-active compound from fluid milk were selected based on flavor dilution factors from gas chromatography-olfactometry. Thresholds for the 13 odor-active compounds were identified using five-set ascending forced choice threshold analysis in odor-free water and fluid skim milk. Model systems were prepared using rehydrated milk retentate (RMR). The aroma of each model was evaluated by descriptive sensory analysis and by difference-from-control testing using a trained panel. The aroma of reconstituted fresh SMP and liquid skim milk were used as controls. Models containing a mixture of twelve of the thirteen chemicals had the most similar odor characteristics to rehydrated SMP aroma (9.0/10) indicating that these compounds constitute the character impact odorants of rehydrated fresh SMP. [source] A STUDY OF CHINESE-ORIGIN AND EUROPEAN-ORIGIN AUSTRALIAN CONSUMERS' TEXTURE PREFERENCES USING A NOVEL EXTRUDED PRODUCTJOURNAL OF SENSORY STUDIES, Issue 5 2001J.M. MURRAY ABSTRACT Diverse food choices and preferences are commonly observed between consumers cross-culturally, however, many aspects of these behavioral differences are not yet fully understood. In order to investigate cross-cultural texture preferences, six extruded snack samples, manufactured under different processing conditions to represent a range of textural characteristics were characterized by a trained panel using descriptive sensory analysis. In parallel, thirty-eight naive European-Origin and thirty-seven naive Chinese-Origin Australian consumers (t = 75) rated their preference for the snacks. The snacks were not representative of any snacks on the market and thus represented a " novel" product in both cultures. Additionally, consumers answered a simple questionnaire and completed the food neophobia scale. Results of descriptive analysis indicated significant differences (p,0.01) between the samples for 13 out of 15 descriptive attributes but no significant differences in preference were found between European-origin and Chinese-origin consumers. However, overall analysis of mean effects indicated that Chinese-origin consumers rated samples significantly higher than European-origin consumers (p,0.05), suggesting a cultural bias in the use of line scales. Gender did not influence texture preference, however, age significantly influenced preference for three of the samples (p,0.05) and analysis of mean effects also indicated differences in consumers' ratings which were related to age. Food neophobia classification did not influence preference, although many more Chinese-origin consumers (28) were classified as neophobic than were European-origin consumers (11). [source] FIRMNESS EVALUATION OF SWEET CHERRIES BY A TRAINED AND CONSUMER SENSORY PANELJOURNAL OF TEXTURE STUDIES, Issue 5 2009CAROLYN F. ROSS ABSTRACT The objective of this study was to examine cherry firmness and the ability of a trained and consumer panel to differentiate between cherries of different firmness values. For the trained panel (n = 12) and consumer panel (n = 100) evaluations, two late-maturing, commercially important cherry cultivars were evaluated, "Selah" and "Skeena." For trained panel evaluations, the analytical firmness value of each cherry was determined, although for the consumer panel, cherries were characterized into different firmness categories (low, intermediate and high), after which, a series of paired comparisons were made. "Selah" was the less-firm cultivar by approximately 20 g/mm and consumers could distinguish the more-firm cherry in all comparisons (P < 0.05). For "Skeena," consumers could only distinguish soft versus firm. Trained panelists were able to distinguish between cherries of a minimum analytical firmness value of ,40 g/mm. A model was developed to predict sensory firmness from analytical determinations of firmness (r = 0.63). PRACTICAL APPLICATIONS Developing prediction models to estimate sensory response from analytical data will benefit the fruit industry by potentially allowing the use of analytical measurements as a proxy for sensory evaluation. In addition, understanding the importance of firmness on cherry acceptance and knowing the specific firmness values at which individuals can perceive a difference in sensory firmness is useful for cherry growers to produce a cherry with acceptable texture. [source] STANDARD SCALES FOR CRISPNESS, CRACKLINESS AND CRUNCHINESS IN DRY AND WET FOODS: RELATIONSHIP WITH ACOUSTICAL DETERMINATIONSJOURNAL OF TEXTURE STUDIES, Issue 4 2008MAITE A. CHAUVIN ABSTRACT A trained panel developed rating scales for crispness, crunchiness and crackliness for dry and wet foods based on the auditory perception of selected foods. The newly developed scales were then evaluated by 40 untrained panelists and the sound perception of standard foods was assessed through the analysis of the root mean square (RMS) of the 5-s audio waveforms and multidimensional scaling (MDS). The RMS was highly correlated to auditory sensory perception of crispness (r = 0.83 and 0.96), crunchiness (r = 0.99 and 0.99) and crackliness (r = 0.88 and 0.96) for dry and wet foods, respectively. MDS technique applied for the 40 untrained panelists was instructive in assessing auditory textural differences of naïve panelists and a useful statistical instrument to graphically validate selected scales. Auditory perception of the selected foods were rated similarly using standard auditory texture scales for crispness, crunchiness and crackliness developed by the trained panel (oral evaluation) and MDS results from the untrained panel (recordings). PRACTICAL APPLICATIONS Crispness, crunchiness and crackliness are not only important and useful descriptors of food texture, but are also desirable textural qualities in many foods. The lack of consistency in the procedures used for the evaluation of crunchy, crispy and crackly in sensory studies often results in confusion when training expert panels. Research will benefit textural studies through an improvement of consistent textural definitions and development of standard scales and evaluation techniques. The crispness, crunchiness and crackliness scales developed and applied in the current study represent a new potential standard frame of reference that may be used for training panelists in texture parameters related to food auditory perception. The scales may be considered illustrations demonstrating full and practical ranges for each texture attribute with regard to analyzing auditory parameters of foods and effective objective tools for assessing panelists in descriptive analysis. [source] RELATIONSHIPS BETWEEN SENSORY AND RHEOLOGICAL MEASUREMENTS OF TEXTURE IN MATURING COMMERCIAL CHEDDAR CHEESE OVER A RANGE OF MOISTURE AND pH AT THE POINT OF MANUFACTUREJOURNAL OF TEXTURE STUDIES, Issue 4 2006C.D. EVERARD ABSTRACTS Textural characteristics of 10 Cheddar cheeses with a range of moisture contents and pH values were investigated by sensory and instrumental methods, over a 9-month maturing period. A trained panel of nine assessors described the sensory texture characteristics of the cheeses using 11 texture parameters. Instrumental parameters were derived using texture profile analysis. Relationships between sensory, instrumental, compositional and maturation properties of the cheeses were determined with the aid of principal component analysis and multiple linear regression. Nine sensory parameters significantly correlated with instrumental parameters, e.g., sensory rubbery correlated with instrumental firmness (R = 0.696, P < 0.001), chewiness (R = 0.679, P < 0.001), fracture stress (R = 0.669, P < 0.001) and springiness (R = 0.643, P < 0.001). Sensory firmness corresponded closely with instrumental firmness (R = 0.539, P < 0.001) and fracture stress (R = 0.518, P < 0.001). Sensory and instrumental texture parameters were significantly affected by changes in moisture content, pH and maturation. [source] The effect of supplementation of a white clover or perennial ryegrass diet with grape seed extract on indole and skatole metabolism and the sensory characteristics of lambJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2007Nicola M Schreurs Abstract Condensed tannin in the form of a grape seed extract (GSE) was dosed to weaned wether lambs fed white clover (WC) or perennial ryegrass (PRG) over a 9-week period to determine whether the ,pastoral' flavour and odour of meat could be altered. The concentrations of the pastoral flavour compounds indole and skatole were determined in the rumen fluid, blood plasma and intermuscular fat. The odour and flavour of fat and meat from the slaughtered lambs was assessed by a trained panel. The rumen fluid and blood plasma concentrations of indole and skatole were higher in those lambs fed WC compared to PRG (P < 0.05) and the overall meat flavour intensity was greater when feeding WC (P < 0.01). The observed concentration of indole and skatole in the fat between WC and PRG feeding treatments was not statistically different. Power analysis indicated that increasing the number of lambs per treatment group from 20 to 65 would result in a higher fat skatole concentration (P < 0.05) being detected in lambs fed WC compared to PRG. Dosing with GSE gave a small reduction in skatole concentration in the rumen fluid and reduced plasma concentration of indole and skatole (P < 0.001). Odour and flavour scores of the fat and meat samples were not particularly high however, dosing with GSE lowered the overall and sweet odour and the sheepy, camphor, faecal and barnyard flavour (P < 0.05). Although the plasma concentration of indole and skatole suggests that GSE reduced indole and skatole formation, the intermittent supply of the GSE to the rumen environment was not sufficient to reduce their concentration in the fat. Hence, the small difference in the scores for pastoral odour and flavour attributes associated with GSE treatment may arise from other unknown factors. From a primary investigation, there was no difference in the concentration of indole and skatole in fat samples collected from carcasses before and after chilling. Further investigations into meat pastoral flavour are warranted through feeding condensed tannin-containing forages. Copyright © 2007 Society of Chemical Industry [source] Consumer acceptability, sensory properties and expert quality judgements of Australian Cabernet Sauvignon and Shiraz winesAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 1 2010K.A. LATTEY Abstract Background and Aims:, This study aimed to determine what sensory attributes most drive consumer and expert acceptance for Cabernet Sauvignon and Shiraz wines. Methods and Results:, The sensory attributes of a set of commercial wines were quantified by a trained panel. A subset was assessed blind for liking by 203 consumers and for quality by 67 winemakers. For the total group of consumers, wines with low levels of ,bitterness', ,hotness', ,metallic', ,smoky' and ,pepper' were preferred. In addition, four consumer clusters were identified, each with different sensory drivers of preference, with the attributes ,red berry', ,floral', ,caramel' and ,vanilla' aroma, ,acidity', ,green' flavour and astringency being of importance in distinguishing the different clusters' acceptance scores. The winemakers' quality scores had little relationship with consumer response, although both groups gave low ratings to wines with Brettanomyces -related flavour. Conclusions:, A relatively small set of sensory attributes were of greatest importance to consumer liking, and these generally dominate varietal differences. Winemakers' quality concepts do not closely align with those of the consumers. Significance of the Study:, This study identifies sensory properties of red wines which could be maximised as well as those which should be reduced, allowing producers to better meet consumers' preferences. [source] MATCHING RESULTS OF TWO INDEPENDENT HIGHLY TRAINED SENSORY PANELS USING DIFFERENT DESCRIPTIVE ANALYSIS METHODS,JOURNAL OF SENSORY STUDIES, Issue 5 2002VARAPHA LOTONG ABSTRACT Two independent, highly trained panels separately conducted descriptive analysis of orange juices using different descriptive analysis methods and sets of samples. Lexicons were developed independently. One panel evaluated 23 orange juice products and identified and referenced 24 attributes. The other panel evaluated 17 products and identified 17 attributes for testing. Though not identical, the lexicons developed by both panels were similar overall. To compare the sensory space of the product category, Principal Component Analysis (PCA) and sensory maps were developed separately for each panel. The comparison showed that the underlying sample spaces obtained from both panels were comparable in many ways. Key flavor characteristics for the same types of orange juice products were described similarly by both panels. These data indicate that the process of using highly trained panels that define attributes and use reference standards for descriptive sensory analysis can give objective and comparable information for a product category across different panels. [source] |