Instrumental Color Measurements Research Articles

Effect of Machine, Anatomical Location, and Replication on Instrumental Color of Boneless Pork Loins

ObjectivesWhen determining instrumental color, even when researchers use standardized equipment and the same device with the same operational settings, differences may still persist. It is also not known if the loin, machine, or replication is the greatest contributor to variability in instrumental pork. The objectives were to 1) evaluate the effects of machine, anatomical location and measurement replication on instrumental color and 2) characterize the variation to color contributed by each of these factors. Materials and MethodsBoneless loins were collected from 2 groups of pigs (250 total) that were slaughtered 14 d apart. The first set contained 100 loins and the second set had 150 loins. Loins were aged until 14 d postmortem in the dark at 4°C. After aging, loins were removed from packaging and positioned on tables so that the ventral side was exposed to oxygen, then allowed to oxygenate for at least 20 min. Instrumental color was measured 3 times on the anterior end and 3 times on the posterior end of the loins with 2 different Minolta CR-400 Chroma meter devices. Each Minolta was programmed to use a D65 illuminant, 0° observer with an 8 mm aperture, and calibrated with white tiles specific to the machine. A total of 12 instrumental color measurements were collected on each loin. Color data were analyzed with the MIXED procedure of SAS (SAS Inst. Inc., Cary, NC) as a split-split plot design where loin served as the experimental unit. The whole plot was machine, the split plot was location, and the split-split plot was replication. The VARCOMP procedure in SAS was used to estimate the proportion of variation contributed by each factor to CIE L*, a*, b*, chroma, and hue. ResultsLoins evaluated with machine 1 were instrumentally 0.71 L* units darker (P < 0.01), 1.09 b* units more yellow (P < 0.01), 0.47 chroma units more saturated (P < 0.01), and had a hue angle 5.12 units greater (P < 0.01) than when evaluated with machine 2 but were not different (P = 0.24) in terms of redness. The anterior portion of the loin was lighter, less red, more yellow, more saturated and had a greater hue angle than the posterior end (P < 0.01). All color traits increased (P < 0.01) as replication number increased. Inherent color differences in the loin contributed the greatest proportion of variability for lightness (58%), redness (57%), yellowness (70%), saturation (70%) and hue angle (49%). Machine contributed a small amount of variation to lightness (1%) and saturation (3%), a greater amount to yellowness (23%) and hue angle (31%) but did not contribute to variability for redness. Anatomical location contributed 41% to lightness, 43% to redness, 7% to yellowness, 27% to saturation and 31% to hue angle. Replication did not contribute to total variation for any color traits. ConclusionOverall, there were differences in instrumental color values between the 2 machines tested but those differences were likely less than the threshold for detectability by a consumer. Even so, inherent differences in the loin was a greater contributor to total variability than the differences between the 2 machines.

Enhancing Sensory Perception of Plant Based Nutraceutical Drinks by Combining Plants from Different Sources: A Preliminary Study of Tea and Ginger Blend.

Tea-ginger drink was selected for evaluation due to its nutraceutical potential. Panelists rated preference for drinks prepared from tea, ginger, and tea+ginger powder for colour, taste, and aroma. The obtained data were evaluated using analysis of variance, principal component analysis, and agglomerative hierarchical clustering. Also the colour preference scores were evaluated against instrumental colour measurements. The ginger drink had lower rating for colour preference and the tea drink had lower ratings for aroma and taste preference. However, the tea-ginger drink led to enhanced colour, aroma, and taste ratings. The colour preference was found to have highest correlation coefficient with the hue and chroma of the drinks [r(58)=−0.583, P<0.05 and r(58)=0.566, P<0.05]. This study suggests that a sensory quality deficiency in a particular plant based drink could be compensated for by blending the drink with another plant based drink. This approach could help improve the uptake of plant based nutraceutical drinks.

Improving the lean muscle color of dark-cutting beef by aging, antioxidant-enhancement, and modified atmospheric packaging.

The objective was to evaluate the effects of wet-aging, rosemary-enhancement, and modified atmospheric packaging on the color of dark-cutting beef during simulated retail display. No-roll dark-cutting strip loins ( = 12; pH > 6.0) were selected from a commercial packing plant within 3 d postharvest. Using a balanced incomplete block design, dark-cutting loins were sectioned in half, and assigned to 1 of 3 aging periods: 7, 14, or 21 d. After respective aging, each aged section was divided into 3 equal parts, and randomly assigned to 1 of 3 enhancement treatments: nonenhanced dark-cutting, dark-cutter enhanced with 0.1% rosemary, and dark-cutter enhanced with 0.2% rosemary. Following enhancement, steaks were randomly assigned to 1 of 3 packaging treatments: high-oxygen modified atmospheric packaging (HiOx-MAP; 80% O and 20% CO), carbon monoxide modified atmospheric packaging (CO-MAP; 0.4% CO, 69.6% N, and 30% CO), and polyvinyl chloride overwrap (PVC; 20% O). Instrumental and visual color measurements were recorded during 5 d simulated retail display. Lipid oxidation was determined utilizing the thiobarbituric acid reactive substances (TBARS) method. There was a significant packaging × enhancement × display time interaction for values and chroma ( 0.001). On d 0 of display, dark-cutting steaks enhanced with 0.1% and 0.2% rosemary and packaged in HiOx-MAP had greater ( 0.001) values and chroma than other dark-cutting packaging/enhancement treatments. A significant packaging × enhancement × display time interaction resulted for values ( 0.001). Dark-cutting steaks enhanced with 0.2% rosemary and packaged in HiOx-MAP was lighter ( 0.001; greater values) than other dark-cutting treatments on d 5 of display. There were no differences ( 0.34) in discoloration scores on d 5 among different dark-cutting treatments when steaks were packaged in HiOx- and CO-MAP. There was an aging period × enhancement × packaging interaction ( < 0.0033) for lipid oxidation. On d 0 of display, there were no differences ( 0.54) in TBARS values between different aging periods and enhancement treatments. Dark-cutting steaks enhanced with 0.2% rosemary had lower ( 0.001) TBARS values than 0.1% rosemary on d 5 when aged for 21 d and in HiOx-MAP. The results suggest that rosemary enhancement with CO- or HiOx-MAP has the potential to improve the surface color of dark-cutting beef.

Internal preference mapping of milk-fruit beverages: Influence of color and appearance on its acceptability.

The individual preferences of 100 consumers between 20 and 30 years old for the color of 16 milk–fruit juice beverages (MFJB) were investigated by preference mapping technique. Consumers were asked to evaluate, just by looking at the samples, how much they liked them (from “Extremely dislike” to “Extremely like”). The color of the samples was analyzed by two different instrumental techniques. Results obtained from the instrumental color measurement showed the wide diversity in hues of the beverages available in the market, and correlations between techniques proved that both of them were appropriate to analyze color.Results showed that participants preferred samples with orangish appearance instead of those with a whiter look. Anyway, punctuations given by the consumers suggest that generally, color of these products is not highly evaluated by consumers, as the best mean punctuation was 6.6.

Tooth colour and whiteness: A review

ObjectivesTo review current knowledge concerning the application of colour science on tooth colour and whiteness description, measurement, distribution and its psychological impact. Data sources“Scopus” databases were searched electronically with the principal keywords tooth, teeth, colour, white, whiteness. Language was restricted to English and original studies and reviews were included. Conference papers and abstracts were excluded. ConclusionsThe appearance and colour of teeth are a common concern for patients across many populations and are associated with an increased desire for treatments that improve dental aesthetics, including tooth whitening. The application of colour science in dentistry has allowed the precise description of tooth colour and whiteness. Coupled with the advances in instrumental tooth colour measurement, such as spectrophotometers, colorimeters, spectroradiometers and digital imaging systems, these parameters are quantifiable in a reproducible and robust manner. These principles have been applied to the tooth colour distribution in many study populations, indicating, in general, differences in tooth colour for subject age and gender, but not for ethnicity. Psychophysical studies on tooth colour and whiteness via third party assessment of images indicate that whitened teeth lead to judgements that are more positive on personality traits such as social competence and appeal, intellectual ability and relationship satisfaction.

CARACTERÍSTICAS SENSORIAIS E INSTRUMENTAIS DO LEITE PASTEURIZADO INTEGRAL

O objetivo deste estudo foi determinar o perfil sensorial do leite pasteurizado integral, e relacionar os resultados sensoriais e instrumentais. Foram coletadas, aleatoriamente, cinco amostras de marcas diferentes de leite pasteurizado integral (marcas A, B, C, D e E), comercializadas no município de Erechim, RS, das quais duaseram homogeneizadas e três não homogeneizadas. As medidas de cor instrumental foram realizadas através da escala CIELAB (L*, a*, b*). Os atributos sensoriais foram avaliados através da análise descritiva de perfil livre e o teste de aceitação foi realizado por 44 consumidores utilizando uma escala hedônica hibrida de 9cm. A partir dos resultados foi possível verificar que as amostras de leite que foram submetidas aetapa de homogeneização, durante o processo de fabricação do leite pasteurizado, apresentaram uma coloração mais branca e uma aparência mais homogênea, quando comparada com as amostras de leite que não foram submetidas a homogeneização. No entanto, estes termos sensoriais não influenciaram na aceitação dos leites, uma vez que a amostra que apresentou menor valor médio (3,8) para aceitação foi a marcade leite submetida a etapa de homogeneização. Através da análise da relação obtida entre os resultados das variáveis estudadas, foi possível observar uma forte correlação entre as medidas sensoriais e instrumentais realizadas nas diferentes amostras de leite, demonstrando a importância da realização da correlação entre estas medidas para a indústria de alimentos e pesquisadores, uma vez que as análises sensoriaisdescritivas são obtidas com maior demanda de tempo e custo.

Partial replacement of animal fat by oleogels structured with monoglycerides and phytosterols in frankfurter sausages

Sunflower oil was structured with monoglycerides and phytosterols. The properties of the oleogels were studied by optical microscopy, large deformation mechanical measurements, dynamic rheometry and differential scanning calorimetry. The interaction between monoglycerides and phytosterols resulted in stronger oleogel networks with a differentiated crystalline structure, increased hardness and gel strength, increased storage modulus (G′) values and decreased melting temperatures compared to monoglycerides oleogels. The oleogel structured with 15:5 monoglycerides to phytosterols weight ratio was selected to replace 50% of the pork backfat in frankfurter sausages. The control treatment (FSS1) presented higher values of hardness, brittleness, gumminess and chewiness than the oleogel-substituted samples (FSS2), whereas cohesiveness and elasticity did not present any differences. Instrumental color measurements indicated that FSS1 samples had higher a*, lower L* and similar b* values compared to FSS2. No differences were detected in the oxidation levels and sensory evaluation revealed similar overall liking for the two treatments.

Multilateral spectral radiance factor scale comparison.

The field of spectral radiance factor (SRF) measurements has seen growing interest in recent years. Scale conformity has so far only been established between the national metrology institutes (NMIs) of Germany and the USA. This study aims at a bigger, multilateral scale comparison. For this purpose, a total of six NMIs participated in a scale comparison of goniospectrophotometers based on neutral and colored diffusely reflecting ceramics samples. In addition, two universities, providing a home-built gonioreflectometer and two widely used commercially available color measurement instruments, respectively, were involved. The wavelength range of the scale comparison covers the visible wavelength range from 380 nm to 780 nm. Results indicate systematic issues and that the uncertainty evaluation of the NMIs requires further work; although for the greatest part of the covered spectral range the agreement is good.

Optical properties of cotton and nylon fabrics coated with silica photonic crystals

In this work, colourant-free coloured fabrics have been produced by the self-assembly of silica nanoparticles (SNPs) using a natural sedimentation method. The optical properties of the SNP-coated fabrics were investigated and the spectral reflectance, chromaticity coordinates, and CIE L* a* b* values are reported. The overall colour effect on the fabric can be described by Bragg’s diffraction of the ordered SNP photonic crystal and the Mie scattering of the disordered SNP arrangement. It was found that the structural colour on the tight black woven cotton fabric was more uniform than that from the loose black knitted nylon fabric. Although the structural colour was not easily perceived on a white fabric due to the strong reflection of the white background, the SEM images show that an ordered photonic crystal was formed on the fabric and a small colour difference by the introduction of SNPs was measured using instrumental colour measurement.

Nutritional value of horse meat and products on the Slovenian market

The nutritional value of three muscles (Longissimus lumborum, Biceps femoris and Triceps brahii) sampled from six horses of breed Posavec and two meat products were determined by the physicochemical, instrumental and sensory analysis. The basic chemical composition (water, fat, protein and ash content as well as fatty acid profile) and the pH value on raw muscles and two meat products were analysed. Horse meat steaks of 2.5 cm thickness were thermally treated on a double hot-plate grill at a temperature of 220 °C to the internal temperature of 65 °C. Sensory evaluation of the heat-treated samples and meat products were followed by quantitative descriptive analysis using a structured scale. The instrumental measurements of colour (CIE L*, a*, b*) and texture (shear force on muscles and the Texture Profile Analysis test on products) were carried out. On average, 100 grams of meat contains 72.44 ± 1.94 g of water, 1.96 ± 2.33 g of fat, 21.52 ± 1.30 g of proteins, and 1.02 ± 0.06 g of ash, and pH value of 5.64 ± 0.05. Horse meat express an extremely beneficial fatty acid composition (containing 37.8 wt. % of saturated, 36.8 wt. % of monounsaturated and 17.6 wt. % of polyunsaturated fatty acids), the P/S ratio of 0.5 and the n-6/n-3 ratio of 3.6. The tenderer texture is found in the Longissimus lumborum muscle, followed by the Triceps brahii muscle and the Biceps femoris muscle. The colour is defined by the low L* value and high a* and b* values in comparison with the meat of other animals. On average, 100 g of horse hot dog contains 56.27 ± 0.82 g of water, 25.48 ± 0.85 g of fat, 14.04 ± 0.73 g of proteins, 2.47 ± 0.28 g of ash, and pH value of 6.23 ± 0.06, the P/S ratio of 0.5 and the n-6/n-3 ratio of 2.2. On average, 100 g of Posavska sausage contains 55.93 ± 1.28 g of water, 22.13 ± 2.56 g of fat, 18.52 ± 0.97 g of proteins, 3.01 ± 0.09 g of ash, and pH value of 6.16 ± 0.09, the P/S ratio of 0.5 and the n-6/n-3 ratio of 5.8. The panel assessed both products as good with specific characteristic due to the presence of horse meat.

Sorghum Bran as an Antioxidant in Pre-Cooked Ground Pork and Poultry Products

ObjectivesPre-cooked pork and poultry products high susceptibility to lipid oxidation is a major concern to the processed meat industry. The development of off-flavors, such as cardboard, painty, fishy, and warmed-over flavor (WOF), from lipid oxidation limits the frozen shelf-life of these products to less than 6 mo. To retard lipid oxidation, antioxidants such as synthetic antioxidants, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), or natural antioxidants such as rosemary extract are common antioxidants added to products to increase shelf life. With an increase in demand for more natural ingredients, recent research has shown that plant-based tannin producing sorghum bran is a quality inhibitor of lipid oxidation. The objective was to evaluate antioxidant effectiveness, pH, color, and sensory of powdered High Tannin and Onyx sorghum bran in a ground pork and ground chicken products.Materials and MethodsGround pork (20% lipid) and dark meat chicken thighs, respectively, were ground, mixed and equally divided into one of 11 treatments: 1) control-no added ingredients; 2) BHA and BHT at.01% of the meat weight; 3) rosemary at 0.2%; 4, 5, 6, and 7) 0.125, 0.25, 0.50, and 0.75% Onyx sorghum bran, respectively; and 8, 9, 10, and 11) 0.125, 0.25. 0.5, and 0.75% high tannin sorghum (HTS), respectively. Patties and crumbles were cooked to 70°C and packaged aerobically on Styrofoam trays overwrapped with polyvinyl chloride film and stored at 4°C for 0, 1, 3, and 5 d under continuous exposure to 1,600 lx, fluorescent lighting. Products were re-heated to 70°C and served to a trained sensory panel on d 1 and d 3. On each storage day, re-heated chicken patties and pork crumbles were evaluated for TBARS, pH, instrumental color, and subjective color measurements. Data were analyzed as a factorial arrangement by Analysis of Variance using the general linear model (GLM) procedure of SAS (Version 6.12; SAS Inst. Inc., Cary, NC) with a predetermined significance level of P ≤ 0.05.ResultsIn control pork crumbles and chicken patties, TBARS values increased with storage (P < 0.0001). By d 5 of storage, Onyx 0.5%, Onyx 0.75%, HTS 0.5%, and HTS 0.75% had lower TBARS values than control and rosemary extract-treated samples (P < 0.002). Treatments affected subjective color, CIE color values L* and b* for both cooked products. The higher the percentage of sorghum added resulted in higher subjective color scores, and the products were darker and less yellow (P < 0.05) than the control and rosemary extract-treated samples. Pork crumbles with higher sorghum bran levels were redder (P < 0.0001) than control crumbles. Heated oil, sorghum, warmed over, gritty, cardboardy, refrigerator stale, painty, brown roasted, astringent, sweet, sour, and nutty flavor aromatics differed across treatments (P < 0.05) in the pork crumbles. Sorghum, brown roasted, bitter, umami, heated oil, refrigerator stale, and sweet differed (P < 0.05) across treatments in the chicken patties.ConclusionThe addition of higher levels of sorghum bran impacted flavor attributes compared to controls but resulted in darker cooked product color. Both varieties of sorghum bran retarded lipid oxidation equal to BHA/BHT but was significantly more effective than rosemary extract (P < .05) in cooked pork crumbles and chicken patties without negatively affecting sensory attributes.

Meat quality characteristics of two South African goat breeds after applying electrical stimulation or delayed chilling of carcasses

Two post slaughter procedures namely, electrical stimulation (220V for 30s, then chilling at 4°C) and delayed chilling without electrical stimulation (10–15°C for 6h, 4°C until 24h) were tested on carcasses of Boer and South African indigenous goats (n=10 goats per breed). The aim of the study was to assess the ideal slaughter conditions for optimum goat meat quality. Temperature and pH profiles, instrumental colour measurements (CIE L*, a*, b*, Chroma and hue angle), surface myoglobin pigments (deoxymyoglobin, oxymyoglobin and metmyoglobin), water holding capacity (WHC), thawing losses, cooking losses, sarcomere lengths and Warner Bratzler shear force (WBSF) values were evaluated on M. longissimus dorsi (LD) and semimembranosus (SM) samples. Both electrical stimulation and delayed chilling treatments resulted in sarcomeres longer than 1.9μm, therefore there were no cold shortening effects. The SM samples of electrical stimulation treatment had lower (P<0.01) WBSF values than corresponding samples of delayed chilling treatment. The LD samples of delayed chilling treatment recorded higher instrumental colour values than corresponding samples of electrical stimulation treatment. Electrical stimulation led to an increase (P<0.05) in cooking losses, but had no effect (P>0.05) on WHC, or thawing losses of LD samples. Breed had no effect (P>0.05) on meat quality characteristics. This study confirms that electrical stimulation has a higher potential than delayed chilling of carcasses in improving goat meat tenderness. Delayed chilling could be more beneficial in improving goat meat colour.

Profiles of colour, minerals, amino acids and fatty acids of musculus longissimus thoracis et lumborum of Ghungroo pigs

Carcass composition and meat quality were evaluated in Ghungroo, the first registered indigenous pig breed of India. Ghungroo pigs (16 gilts and 26 barrows) were slaughtered at the age of 10 months for evaluating the different parameters. Instrumental colour measurement indicated that the coordinates were in the following range: lightness (L*), 39.17 - 57.39; redness (a*, red ± green), 8.37 - 14.21; and yellowness (b*, yellow ± blue), 13.08 - 18.17. Haem iron content was significantly higher in barrows compared to gilts. The mineral contents in the musculus (M.) longissimus thoracis et lumborum were in the following range: potassium, 289 – 349 mg/100g; zinc, 0.58 – 0.91 mg/100g; copper, 0.13 – 0.17 mg/100g; manganese, 0.05 –0.06 mg/100g and magnesium, 4.72 –7.37 mg/ 100g. Significant differences were not observed in the concentration of any of the estimated amino acids between the sexes. Fatty acid profiling of M. longissimus thoracis et lumborum indicated that saturated and unsaturated fatty acids were in the range of 32.17 - 41.19% and 58.98 - 68.15%, respectively. Results further indicated a concentration of 0.88 – 1.73% omega-3 fatty acids; 19.95 - 27.23% omega-6 fatty acids and 14.52 - 23.47% essential fatty acids in the Ghungroo muscle tissues.

The Effect of Delivery System and Light Activation on Tooth Whitening Efficacy and Hydrogen Peroxide Penetration.

To evaluate the whitening efficacy of a new two-layer technology in-office system compared to a conventional gel-type system and determine hydrogen peroxide penetration (HPP) into the pulp cavity. Extracted molars (n = 60) were assigned to group NC: glycerol gel; group QPRO: 20% HP varnish (Zoom Quick Pro, Philips Oral Healthcare); group ZOOM_NL: 25% HP gel (Zoom Chairside Whitening); and group ZOOM_WL: 25% HP gel (Zoom Chairside Whitening) with light-activation. HPP levels were estimated with leucocrystal-violet and horseradish-peroxidase. Instrumental color measurements were performed at baseline (T0 ), 1-day post first whitening (T1 ), 1-day post second whitening (T2 ), 1-day post third whitening (T3 ), and 1-month post whitening (T4 ). One-way analysis of variance followed by post hoc Tukey's HSD test was performed to detect difference in ΔE* and HP penetration levels (α = 0.05). ΔE* of NC was lower than other groups, whereas ΔE* of ZOOM_WL was greater than the other three groups, at T3 and T4 . Mean HPP level obtained from ZOOM_WL (1.568 ± 0.753 μg/mL) was significantly greater than those obtained from the other groups, whereas the mean HPP level observed in NC group (-0.131 ± 0.003 μg/mL) was significantly lower than the other groups. Tooth whitening efficacy and HPP levels vary based on whitening systems used. The two-layer technology in-office varnish system may be an alternative whitening option to reduce chair time in the office. (J Esthet Restor Dent 28:313-320, 2016).

Technical Note: Gray tracking in medical color displays-A report of Task Group 196.

The authors discuss measurement methods and instrumentation useful for the characterization of the gray tracking performance of medical color monitors for diagnostic applications. The authors define gray tracking as the variability in the chromaticity of the gray levels in a color monitor. The authors present data regarding the capability of color measurement instruments with respect to their abilities to measure a target white point corresponding to the CIE Standard Illuminant D65 at different luminance values within the grayscale palette of a medical display. The authors then discuss evidence of significant differences in performance among color measurement instruments currently available for medical physicists to perform calibrations and image quality checks for the consistent representation of color in medical displays. In addition, the authors introduce two metrics for quantifying grayscale chromaticity consistency of gray tracking. The authors' findings show that there is an order of magnitude difference in the accuracy of field and reference instruments. The gray tracking metrics quantify how close the grayscale chromaticity is to the chromaticity of the full white point (equal amounts of red, green, and blue at maximum level) or to consecutive levels (equal values for red, green, and blue), with a lower value representing an improved grayscale tracking performance. An illustrative example of how to calculate and report the gray tracking performance according to the Task Group definitions is provided. The authors' proposed methodology for characterizing the grayscale degradation in chromaticity for color monitors that can be used to establish standards and procedures aiding in the quality control testing of color displays and color measurement instrumentation.

Synthetic white pigments (white titanium and white zinc) in different binding media. Influence of environmental agents

This work concerns the behaviour of white pigments of white titanium and white zinc in different media both of natural and synthetic binders. In addition, a study was made of the impact that time, high-energy UV radiation, heating by infrared radiation, or saturation processes of relative humidity exert on stability and chromaticity of the samples. The composition of pigments and binders as well as the time course of their samples were studied by X-ray diffraction, mass spectrometry, electron microscopy, and instrumental colour measurement. The effect of the aging, UV, and infrared exposure together with moisture saturation were found to result in losses in elasticity and cracking of the film generated by the binder, the latter two factors causing the most severe losses. The greatest variations were detected in the colorimetric study, reflecting the utility of instrumental colour measurements for these types of studies. The chromatic variations detected consist fundamentally of loss in luminosity (ΔL) and chroma (ΔC) as well as a slight yellowing tendency. In general, the samples based on natural binders were more affected that those based on synthetic products.

Color Properties of Demineralized Enamel Surfaces Treated with a Resin Infiltration System

To assess color properties of white spot lesions (WSLs) following resin infiltration treatment in vitro. WSLs were artificially created on 30 extracted human teeth. Two groups were formed: (a) control, and (b) resin infiltrant group (n = 15, each). Instrumental color measurements were performed using a spectrophotometer and visual color evaluation was performed by three independent evaluators. Color assessment was determined at three time points: baseline (T0), after WSL formation (T1), and after resin infiltrant or control treatment (T2). CIELAB color coordinates were determined and the resultant color difference (ΔE*) was calculated between the time points. Two-way repeated measures analysis of variance (ANOVA) and One-way ANOVA analyses were used to evaluate the color changes. Pearson chi-square analysis was performed to evaluate the visual ratings between treatment and control groups. Level of significance was set p <0.05. After treatment of WSLs there was a significant color change (ΔE*) between treatment and control groups (p <0.05). Resin infiltration group showed a regression of all values toward the pretreatment levels. There was a significant difference in visual evaluation ratings between groups after treatment; treatment group had all surfaces receive a rating of being clinically acceptable, with 73% of these surfaces having no perceptible color difference to adjacent sound enamel. Meanwhile, control group received ratings of all surfaces having a visual color difference that was deemed as unacceptable (p < 0.05). In-vitro resin infiltration for the treatment of enamel WSLs produced a significant improvement in color, reverting L*, a*, and b* values back toward baseline values. Resin infiltration of enamel white spot lesions on teeth is capable of managing the esthetic problem by reverting the L*, a*, and b* color coordinates back to their baseline values. (J Esthet Restor Dent 28:339-346, 2016).

Physicochemical, Biochemical and Instrumental Attributes and Consumer Acceptability of Dry-Fermented Sausages Elaborated with Combined Partial Substitutions of Sodium Chloride and Pork Backfat

We performed 6 fabrications of dry-fermented sausages to investigate, at laboratory scale, the effects of combined partial substitutions of sodium chloride by potassium chloride and pork backfat by sunflower oil on key physical-chemical and biochemical parameters, instrumental colour and texture measurements, and the consumer acceptability of the end-products. Regarding the physical-chemical parameters, statistical analysis of results showed that final product weight loss was impacted by fat content and use of sunflower oil; final mean water activity value was only affected by salt level; and animal fat content impacted pH values, only at the end of drying. Regarding the biochemical parameters investigated, we statistically found a marked impact of partial substitution of NaCl by KCl on the proteolysis evolution, of fat level and sodium content on the end-product lipolysis, and finally, a significant effect of animal fat level and incorporation of sunflower oil on both protein and lipid oxidations. However, the new product formulations combining salt and fat substitutions lead to globally acceptable water loss and water activity values and similar rates of proteolysis, lipolysis and lipid oxidation, but less protein oxidation. From a practical point of view, the results clearly showed that sodium and animal fat contents in dryfermented sausages can be drastically reduced with no too marked adverse effect on colour, final textural properties or consumer acceptability. On the basis of these laboratory results, new healthier dry-fermented products can be manufactured by an industrial company in the near future.

Determining the relationship between pH and instrumental color measurements to predict water-holding capacity and sensory juiciness

Determining the relationship between pH and instrumental color measurements to predict water-holding capacity and sensory juiciness

Physico-chemical Changes in Liquid Smoke Flavoured Yellowfin Tuna (Thunnus albacares) Sausage During Chilled Storage

A liquid smoke flavoured sausages were prepared from yellowfin tuna using a commercial liquid smoke flavouring. Physico-chemical changes in the sausages during chilled storage at 3 ± 1 °C were analysed and compared with that of a control. Total plate count was estimated at every 15th day of storage. Liquid-smoked sausages were were found to have higher moisture content but recorded lower values for total volatile base-nitrogen, trimethylamine and thiobarbituric acid (P 0.01). Instrumental colour measurements showed lower L* (lightness), a* (redness) and b* (yellowness) values for liquid smoke flavoured sausages (P < 0.01). The liquid-smoked sausages showed lower hardness values (P < 0.01). Both liquid-smoked and control sausages were found to be sensory wise acceptable up to 55th days of storage and subsequently rejected on the 60th day. The microbial count in both the types of sausages was within the acceptable limit during this period.