Vane Rheometry for Textural Characterization of Cheddar Cheeses: Correlation with Other Instrumental and Sensory Measurements

The relationship between instrumental (vane method, texture profile analysis (TPA), uniaxial compression) and sensory texture measurements of Cheddar cheeses was investigated. A Haake VT 550 viscotester equipped with a four-bladed vane rotor was used for the vane test. Instrumental TPA was performed with a TA.XT2 Texture Analyser, and compression variables were calculated from TPA data. Vane parameters were significantly correlated with respective variables of compression and TPA (r=0.56-0.91), and sensory tests (r=0.54-0.88). Multivariate analysis indicated that seven sensory attributes of ten commercial Cheddar cheeses were satisfactorily predicted (calibration regression coefficient,R_cal >0.62) by variables of the vane, uniaxial compression and TPA tests. In particular, cheese firmness and cohesiveness evaluated by sensory panel were well described by vane stress and apparent strain. The results validate the vane method as an alternative to the existing cheese testing methods for rapid evaluation of cheese texture.     

Instrumental and sensory evaluation of cooked pasta during frozen storage

Food consumption patterns have changed significantly during the last years, showing an increase in the consumption of convenience foods. Frozen foods represent an important segment of this market. The aim of the present paper was to study the influence of frozen storage on the quality of cooked organic tagliatelle. Instrumental measurements of different quality parameters (moisture content, colour, textural and rheological characteristics of frozen cooked pasta) were performed during twelve months of storage. The sensory properties of pasta were also evaluated by means of an acceptability study. In general, both instrumental and sensory analysis found that frozen storage affects negatively the acceptability of cooked pasta. The advantages obtained through fast freezing procedures are not maintained along storage, being hardness (instrumental) and consistency (sensory) the most relevant quality indices. Finally, the shelf life of the product was calculated as 3.6 and 3.8 months in the cryogenic device and air‐blast tunnel, respectively, based on simple kinetic models.     

LIQUID HOLDING CAPACITY AND INSTRUMENTAL AND SENSORY TEXTURE PROPERTIES OF HERRING (CLUPEA HARENGUS L.) RELATED TO BIOLOGICAL AND CHEMICAL PARAMETERS

Instrumental texture measurements done on raw herring fillets only partly describe the sensory texture of marinated herring fillets. Sensory texture parameters of marinated fillets were related to instrumental texture measurements of raw fillets by three different data analysis approaches. Uniaxial compression measurements were used as a single parameter, as compression curves or fitted to polynomials. Data from all three methods were related to sensory firmness (r = 0.310–0.366, P < 0.05). Elasticity could be predicted from the maximum compression force (r = 0.181, P < 0.05). The compression curve contained information correlating with all the measured sensory texture parameters (r = 0.102–0.310, P < 0.05), while the fitted polynomials, in addition to firmness, could predict fatty mouthfeel (r = 0.201, P < 0.05). The most information about the sensory texture was obtained from the compression curves. This study shows that the texture properties of herring are highly intercorrelated and can be regarded as a multivariate complex of parameters. The liquid holding capacity (LHC), defined as the moisture held after a low centrifuge speed expressible moisture measurement, and the texture of herring are influenced by a variety of factors, e.g., spawning time of year, gonad maturity, body size, age and lipid content (P < 0.05). Increases in body weight, age and lipid content are intercorrelated and result in marinated fillets being more firm, elastic, juicy and fatty. Decreases in these factors will give marinated fillets that are perceived to be gritty and with low intensities of firmness, elasticity, juiciness and fatty mouthfeel.     

Prediction of sensory textural properties from rheological analysis for process cheeses varying in emulsifying salt,protein and moisture contents

Textural characteristics of process cheeses varying in emulsifying salt (disodium phosphate), protein and moisture contents were evaluated by rheological compression using texture profile analysis and by sensory evaluation. The primary objective of this study was to predict sensory textural parameters using instrumental rheological parameters. All sensory parameters correlated with one or more instrumental parameters, e.g. rheological firmness versus sensory firmness (R = 0.98, P < 0.001), rheological chewiness versus sensory rubbery (R = 0.92, P < 0.001) and rheological chewiness versus sensory chewy (R = 0.86, P < 0.001). Partial least squares calibration models were developed for each of nine sensory parameters using instrumental parameters. Principal component analysis of instrumental and sensory parameters illustrated relationships among parameters. It was shown that instrumental parameters could be used to supplement sensory evaluation of process cheese texture. Increasing emulsifying salt content increased firmness, springiness and chewiness and decreased adhesiveness, mouthcoating and mass formation. Increasing protein content resulted in increased fracture strain and stress and chewiness and decreased melting. Increasing moisture content increased cohesiveness and decreased firmness and chewiness. Copyright © 2007 Society of Chemical Industry     

COMPARISON OF TWO INSTRUMENTAL METHODS WITH SENSORY TEXTURE OF PROTEIN GELS2

The textural attributes of 8 different heat-induced protein gel preparations evaluated by torsion failure testing and Instron texture profile analysis (TPA) were compared to sensory ratings by a trained texture profile panel. The gels presented a wide range of textural properties as determined by the instrumental and sensory parameters. Among the instrumental parameters, true shear strain at failure was the most frequent and significant predictor of sensory notes. Initial shear modulus and 50% compression force had the poorest correlations with sensory notes. Comparison of the two instrumental tests produced high correlations between shear stress at failure and TPA hardness; true shear strain at failure and TPA cohesiveness; and, initial shear modulus and 50% compression force. High correlations were also observed among various panel notes. Canonical correlation analyses showed that sets of linear combinations of parameters from each one of the 3 tests (torsion, TPA or sensory) were highly correlated to sets from either of the other two. Regression equations relating each of the instrumental tests to sensory notes were developed. Of the torsion failure parameters, the logarithm of true shear strain most commonly appeared in the equations. Of the TPA parameters, cohesiveness and its logarithm were the terms that were most frequent. High R² values were obtained for regression equations developed for predicting torsion failure parameters based on TPA parameters.     

Quality of Whole Lobster (Homarus americanus) Treated with Sodium Tripolyphosphate Before Cooking and Frozen Storage

ABSTRACT: The objective of this study was to determine the effects of pre-rigor treatment of lobster muscle with sodium tripolyphosphate (STP) before cooking, cryogenic freezing, and frozen storage. STP concentrations of 0.1% and 0.3% were prepared in 0.9% saline solution and injected into lobster before processing. Controls were injected with 0.9% saline solution. Lobsters were then steam-cooked, cryogenically frozen, and stored at −15 °C. Chemical and textural analyses were conducted on reheated samples at storage months 0, 2, 4, and 6, and sensory analyses were conducted at months 2 and 6. Cook loss results showed the 0.3% STP-treated lobsters had a 5% significantly ( P 0.05) lower cook loss than the 0.1% STP and control samples. Yield results revealed that STP-treated tails had a 0.7% to 0.8% significantly ( P 0.05) higher meat yield than control samples. Total moisture results showed that STP-treated lobster tail and claw meat had higher total moisture levels compared with control samples at month 6. Sensory results revealed that panelists rated both 0.1% and 0.3% STP-treated lobster tails significantly ( P 0.01) higher for flavor and texture, and significantly ( P 0.001) higher for overall acceptability than control samples at month 6. The results indicated that STP added at low concentrations may extend the shelf life of whole cooked cryogenically frozen lobster, decrease lipid oxidation over frozen storage time, maintain texture, color, and flavor attributes, increase yield, and decrease drip loss.     

Determination of Ketchup Sensory Texture Acceptability and Examination of Determining Factors as a Basis for Product Optimization

The aim of this study was to examine possible usage of instrumental determination of selected texture parameters to estimate sensory texture acceptability of ketchups. Likewise, the authors focused on examination whether the consumer’s perception of texture acceptability is connected to the selected factors related to the ingredients and production technology. Yet another aim was to describe the selected textural parameters of ketchups available in the European market. Within the frame of this study, 29 samples of ketchups were analyzed by means of instrumental and sensory texture analysis. Further, a survey research was carried out with the results showing that the texture was the second most significant parameter for the consumer’s choice of a particular product. The average evaluation of sensory texture acceptability reached the values from 3.78 to 7.67. Analysis of the evaluation results of textural parameters based on the values of Pearson’s correlation coefficient confirmed a high correlation (p < 0.05) between instrumental and sensory determined viscosity and density. However, none of these partial textural parameters affected the sensory acceptability of the texture separately. Thus, using the instrumental analysis for estimation of the sensory texture acceptability of ketchups is not possible. For the optimization and control of ketchup texture in practice, sensory analysis is essential.     

INFLUENCE OF ENZYMES ON THE TEXTURE OF BROWN PAN BREAD

Enzymes are commonly used to improve the textural quality of bread and to extend its shelf life. To study the effect of enzymes on the texture of brown pan bread, four types of bread were industrially manufactured using amylase, xylanase, a mixture of amylase : xylanase (1:1) and control (no enzyme). After baking, the bread samples were stored for 1, 4, 7, 10, 13, 15 and 17 days. At each storage time, bread texture was evaluated by sensory and instrumental methods, and the overall acceptability was determined. Instrumental and sensory texture data showed that the addition of amylase or amylase : xylanase decreased the staling rate of breads. Furthermore, the use of a mixture of amylase and xylanase provided better results than the addition of amylase alone. Therefore, the results suggest that the addition of a mixture of amylase and xylanase is recommended to extend the shelf life of brown pan bread. On the other hand, the addition of xylanase resulted in an increase of the staling rate. The results suggest that when xylanase is used to improve dough machinability, the addition of amylase along with it should be considered in order to prevent an increase of staling rate.     

INSTRUMENTAL TEXTURE STUDIES ON CHOCOLATE IV: COMPARISON BETWEEN INSTRUMENTAL AND SENSORY TEXTURE STUDIES

Texture characteristics of solidified plain chocolate and milk chocolate were determined in instrumental and sensory studies. The instrumental parameters included compression strength, melting properties, maximum tensile force during hesion testing and the maximum size of dispersed solid components. To classify the sensory texture impressions into intensity ranges, by using appropriate samples, a reference scale was derived allowing a sensory panel to assign unknown chocolate samples to the respective intensity ranges. Instrumental control of the reference samples ensures satisfactory relations between instrumental and sensory data.     

TEXTURE ANALYSIS OF CHEDDAR CHEESE MADE FROM ULTRAFILTERED MILK

The textural properties of Cheddar cheese made from ultrafiltered milk were assessed. Cheddar cheeses were prepared from 1.5- and 2.0-fold concentrated milk and ripened for three months. Textural characteristics of the UF cheeses were compared to control and commercial Cheddar cheeses by sensory and instrumental measures. The texture of cheese made from UF milk differed from the control commercial Cheddar cheeses. According to the trained sensory panel, the UF cheeses were harder and more rubbery, crumbly, chewy and grainy than the control and commercial Cheddar cheeses (P <0.01). The texture profile analysis (TPA), conducted using the Instron, did not correspond to the sensory measurements nor was it successful in discriminating among the cheese samples. Lack of agreement between the sensory and instrumental tests was attributed to differences in the testing conditions and procedures of the two methods. Instrumental tests should be validated against sensory measures in order to be useful as measures of palatability. Consumer preferences for the commercial, control and UF Cheddar cheeses were significantly different (P < 0.01), the UF cheeses being less preferred in terms of flavor, texture and overall acceptability.     

Sensory and Instrumental Texture of Snap Bean (Phaseolus vulgaris L.)

A recent study aimed to establish the correlation between instrumental (using Stable Micro System Texture Analyzer) and sensory texture analyses assays in snap bean pods (Phaseolus vulgaris L.). The rupture force correlated significantly and negatively with the sensory traits: parchment layer free, crispness, and stringlessness. Firmness measurements of the raw pods by the texture analyzer indirectly gave enough information to use it as a tool for sensory texture analyses of the processed beans. This could allow breeders to evaluate textural quality of cooked pods in the early stages of the breeding and selection program, thus saving time and costs in doing sensory texture analysis.     

RELATIONSHIP BETWEEN INSTRUMENTAL AND SENSORY PARAMETERS OF COOKED SWEETPOTATO TEXTURE1

This study compared two instrumental methods, namely uniaxial compression and texture profile analysis (TPA), with sensory evaluation in describing the textural properties of cooked sweetpotatoes. The steamed cooked samples (1.35 × 2.2 cm cylinder) of four cultivars and six selections were subjected to a trained texture profile panel for sensory ratings and the two instrumental methods for determination of the mechanical properties. Factor analysis indicated that the 15 sensory variables were grouped into 3 main factors, namely moistness-firmness (factor 1), particles (factor 2), and fiber (factor 3). Among the instrumental parameters, shear stress of compression and fracturability, hardness, and gumminess of TPA correlated highly (R = 0.73–0.95) with both the mouthfeel and mechanical-type sensory notes. These parameters of the two instrumental methods were linearly related (R²≥ 0.95) and could be converted from one to another with a high degree of reliability. Regression equations based on shear stress significantly explained (R²= 0.71–0.91) eight of the sensory notes. These instrumental parameters can be good predictors of cooked sweetpotato texture.     

A METHOD FOR MEASURING THE TEXTURE OF MEAT AND THE EFFECT OF NITRITE AND SALT ADDITION ON THE TEXTURE OF CURED MEATS1

An instrumental technique was developed for measuring the texture of canned chopped ham using the 15 cm ² wire extrusion cell of the Ottawa Texture Measuring System. Its measurement efficacy was evaluated by testing enzymatically tenderized ham. This showed that the technique was sensitive to textural changes and that the level of the added enzyme affected the ham's texture exponentially. Nitrite addition to the canned chopped ham product at levels of 0-1000 ppm did not affect its texture. The level of salt used in the curing solution, however, had a marked tenderizing effect. Similarly, compression tests on wieners indicated that nitrite addition did not influence their texture. It was concluded that the characteristic texture of the two products tested cannot be attributed to nitrite addition and that other factors such as the level of salt addition to the canned chopped ham must be responsible.     

Sensory Characteristics and Instrumental Texture Attributes of Abalones, Haliotis Fulgens and Cracherodii

ABSTRACT: :
Tenderization treatments of black abalone ( Haliotis cracherodii ) were conducted using papain solutions (0.25% or 0.50%) with tumbling (10 or 20 min) prior to canning. The treated adductor and opercular (foot) muscle were evaluated by sensory and instrumental methods and compared to untreated black abalone, to untreated blue abalone ( H. fulgens ) and to commercially canned blue abalone. Treatment with papain did not significantly alter the texture of the abalone but did increase metallic and bitter character notes, possibly by releasing amino acids on protein degradation. Instrumental texture measurements correlated with sensory texture measurements and may aid in the establishment of quality parameters for canned abalone.     

Double freezing of cod fillets: Influence on sensory,physical and chemical attributes of battered and breaded fillet portions

Fillet samples were processed on board a research vessel from cod (Gadus morhua) in different states of rigor mortis. In addition, headed and gutted fish in different states of rigor were frozen and, after ten days of frozen storage, the fish were thawed, processed into fillets and refrozen. During subsequent frozen storage at –24°C of breaded and battered portions processed from the different fillet batches several quality attributes were tested using sensory, physical, and chemical methods. The measurements indicated differences in the quality attributes depending on refreezing and rigor states. Especially the sensory texture attributes gumminess and, with some restrictions, firmness were found to be suitable for distinguishing single frozen (SF) from double frozen (DF) samples. This finding was supported by the outcome of the measurement of penetration force where generally a significantly (p < 0.05) higher force was necessary to penetrate the DF compared to SF samples. DF samples were generally lighter (higher L*) than SF samples. The colour difference δE between both sample types was at least very clear and therefore visible. However, no clear differences between SF and DF samples were found when evaluating the flavour attributes and using instrumental texture profile analysis for texture characterisation. Also, all chemical parameters measured did not allow to clearly distinguish between single and double frozen samples. Therefore, it can be stated that, at least when using cod as raw material for processing battered and breaded portions, the different methods for preparing the fillet blocks will, if at all, only affect the textural quality of the final products.     

Textural Measurements and Product Quality of Restructured Sweetpotato French Fries

The objectives of this research were to investigate the applicability of using an alginate-calcium gelling system to produce a French fry-type product using high beta-carotene sweetpotato puree as the main ingredient and to compare four instrumental methods of texture measurement for this product type in relation to sensory textural properties. Sweetpotato puree made with Jewel cultivar sweetpotatoes was restructured using optimized alginate-calcium concentrations. A consumer panel scored sweetpotato fries containing 0.35 g alginate/100 g and 0.5 g CaSO₄/100 g highest for appearance, texture, flavor, and overall acceptability. A trained texture profile panel described the product with 15 texture notes. Of these attributes, nine sensory notes describing hardness, mastication shear, cohesiveness, springiness, moistness, and oiliness were highly correlated with some instrumental parameters (r=0.79-0.92) for measuring textural properties. The instrumental methods evaluated were instrumental texture profile analysis, three-point bending force, Kramer shear force, and puncture force. Among these instrumental methods, Kramer shear appeared to be the method of choice because of method's simplicity and high precision (coefficient of variation ≤10%).