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LWT 39 (2006) 540–547

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Physical, textural and sensory characteristics of 7-day frozenpart-baked French bread

Laura G. Carra, Maria A.B. Rodasb, Jussara C.M. Della Torreb, Carmen C. Tadinia,�

aFood Engineering Laboratory, Chemical Engineering Department, Escola Politecnica, Sao Paulo University, Sao Paulo, SP,

P. O. Box 61548, Zip Code: 05424-970, BrazilbSensorial Analysis Laboratory, Adolfo Lutz Institute, Av. Doutor Arnaldo, 355, Sao Paulo, SP, Zip Code: 01246-902, Brazil

Received 13 August 2004; received in revised form 3 March 2005; accepted 18 March 2005

Abstract

Bread partially baked for 7min at 250 1C, after cooling, was frozen until core temperature reached �18 1C and stored at this same

temperature up to 7 days. Samples were removed daily from the freezer, thawed and baked at 250 1C for 6min. Analyses were

performed 1 h after final baking, and were also conducted on fresh French bread daily produced (control). Weight and specific

volume of frozen part-baked bread presented significant difference (Po0:05) compared with fresh one. Sensory analysis was carried

out by a trained panel using the Difference from Control test to evaluate the difference and the degree of difference between frozen

part-baked French bread (FPBFB) and fresh bread regarding appearance, tactile by direct touch and mouthfeel. All scores obtained

indicated that the panelists, during the studied period, considered FPBFB to be slightly different compared with fresh one.

Consumer Acceptance test was applied to compare appearance (gloss, roughness and cut on bread surface), oral texture (crust

crispness and crumb firmness) and overall flavor between frozen part-baked bread and a commercial brand. All sensory scores

obtained from Consumer test indicated that the 4-day frozen part-baked presented a superior acceptance to the commercial brand.

r 2005 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.

Keywords: Frozen part-baked French bread; Texture; Sensory evaluation; Freezing

1. Introduction

French bread has 85% of the bread market in Brazil,being the preferred product at all social levels. A typicalFrench bread in Brazil has 50 g of final weight, is 12.5 cmlong and 5.5 cm in diameter. Its crust is brown andglossy with a unique cut largely following the length,and the crumb is soft and white (Carr & Tadini, 2003).

French fresh bread usually presents an appealingbrownish and crunchy crust, a pleasant roasty aromaand a soft and elastic crumb texture. However, freshbread is a product with a short shelf-life and during its

0 r 2005 Swiss Society of Food Science and Technology. P

t.2005.03.012

ing author. Tel.: +5511 3091 2258;

1 2255.

ess: catadini@usp.br (C.C. Tadini).

storage chemical and physical alterations occur, knownas staling.

Those preservation problems in combination withincreasing market demands and the complexibility of thetraditional bread making procedure, which requiresnight or early morning labor, led to new technologies.Frozen partially baked bakery products are leadingproducts in terms of innovation in the bread industryand a trend in expansion in Brazil is the supply of frozenpart-baked bread in convenience stores and super-markets. The advantage of frozen part-baked Frenchbread (FPBFB) is that it requires few types of equipmentat the store and is faster to prepare, since it only needs tobe removed from the freezer and put in the oven.Commercialization of frozen part-baked bread aims atreducing raw materials waste and production space andequipments at the commercialization store. Also there is

ublished by Elsevier Ltd. All rights reserved.

ARTICLE IN PRESSL.G. Carr et al. / LWT 39 (2006) 540–547 541

no need for specialized workers, a standardization ofproduct quality is promoted and selling fresh bread atany time of day becomes possible (Nutrinews, 2001).However, this kind of product is expensive when energyis considered.

Changes in quality of FPBFB can occur due to icecrystals growth during storage time, that damage crumbstructure, altering textural characteristics. Dehydrationand consequent loss of weight can occur during storagetime (Bent, 1998). FPBFB presents a lower specificvolume, a rougher crust, a more compact crumb andfaster staling when compared with fresh bread (Ferreira& Watanabe 1998).

Storage life of FPBFB is often estimated up to 6months. This estimate is based on previous experiencewith breads of similar formulations. Because of thisprolonged storage time bread characteristics perceivedby consumers change, such as toughening of the crust,firming of the crumb and loss of flavor, when comparedwith fresh one.

Ferreira and Watanabe (1998) showed that additionof vegetable shortening and ascorbic acid produced aFPBFB with higher specific volume. Sugar addition didnot improve volume.

Fik and Surowka (2002) analysed organoleptic(appearance, color, smell and taste of product, crustthickness, elasticity, porosity, color homogeneity andcutting ability of the crumb) and textural changes(texture profile analysis (TPA) of the crumb and cuttingof the crumb and crust by a TA-XT2 texturometer) inbread which had undergone part-baking, freezing andfrozen storage, and subsequent thawing followed byrebaking, and results were compared with those changesin the frozen full-baked product. The authors reportedthat stored frozen part-baked bread with 71% fractionof baking time revealed, after rebaking, not onlyfavorable textural features but also a better sensoryquality in comparison with its full-baked counterpartwhich was not reheated. They emphasized that the mostpronounced changes in quality of the studied bread wereobserved at the beginning of the storage period (1 weekafter freezing).

Carr and Tadini (2003) studied the influence of yeastand vegetable shortening quantities on physical andtextural parameters of FPBFB stored for 28 days. Theauthors concluded that higher yeast content formula-tions produced bread with a higher specific volume,whereas addition of vegetable shortening producedbread with lower firmness and chewiness. Frozenstorage time significantly influenced water content andspecific volume of bread. Volume of FPBFB, for allstudied formulations, measured 1 h after final baking,decreased after 7 days of storage, when compared withfresh one.

Barcenas, Haros, Benedito, and Rosell (2003) studiedthe effect of freezing and frozen storage on the staling of

partially baked wheat bread. The authors evaluatedthe amylopectin behavior by differential scanningcalorimetry simulating the baking process, and hardnessincrease in the wheat loaf crumb during frozen storagewas measured in a Texture Analyser TA-XT2i. Aprogressive significant increase of the crumb hardnesswas observed and was more evident beyond 14 days offrozen storage.

Barcenas, Benedito, and Rosell (2004) evaluated theeffect of hydrocolloids (hydroxypropylmethylcellulose(HPMC) and k-carragena) on the quality and staling ofpart-baked bread after frozen storage and rebaking. Thefrozen storage had significant effects on the specificvolume, moisture content, crumb hardness and hard-ening rate during aging, while the addition of HPMCimproves the overall quality of the product during longfrozen storage (up to 42 days).

Vulicevic, Abdel-Aal, Mittal, and Lu (2004) evaluatedphysical, chemical and textural quality characteristics,and sensory attributes for different part-baked breadsstored up to 9 months at frozen conditions, containingoptional ingredients such as fruits, nuts, vegetables orspices. Changes in the quality characteristics of the part-baked bread during the storage period varied consider-ably. Moisture (crust and crumb), springiness andmouthfeel were the most sensitive quality attributes thatwere significantly deteriorated after 4 weeks of storage.

Recently, Le Bail et al. (2005) verified the impact ofselected process parameters (proving, partial baking,post-baking chilling and freezing) on the quality offrozen partly baked bread, mainly crust flaking quanti-fied by evaluating the mass ratio (mass of the crust vs.mass of the bread). Results indicated that chillingconditions before freezing and proving conditions wereby order of importance the most influent parametersaffecting crust flaking. The authors suggest that thesephases of the process should be carried out with a highlyhumid air to minimize crust flaking.

Texture is considered a multidimensional attribute, soit is preferable to refer to textural properties rather thantexture, because there are a number of different texturalproperties (Bourne, 1989). Usually, textural objectivemeasurements are based on force measurements, butother principles such as distance, time, energy andmiscellaneous tests may be used (Szczesniak, 1998). Inbread, firmness of final product texture is the most oftenmeasured, because of the strong correlation betweencrumb firmness and consumer perception of breadfreshness (Axford, Colwell, Cornford, & Elton, 1968;Brady & Mayer, 1985; Hilberd & Parker, 1985;Redlinger, Setser, & Dayton, 1985; Baker & Ponte,1987). Carson and Sun (2001) used TPA to assessfirmness and other textural parameters (cohesiveness,springiness, adhesiveness) of six kinds of bread, andconcluded that the instrumental results of these para-meters were strongly correlated with sensorial analysis.

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The objective of this work was to study the influenceof frozen storage time on physical, textural and sensorycharacteristics of FPBFB stored for 7 days. The mainobjective was to compare these parameters to thoseobtained from fresh bread, when most changes occurduring frozen storage.

Fig. 1. Sample of frozen part-baked French bread prepared for crumb

porosity analysis.

2. Materials and methods

2.1. Materials

The ingredients used to produce FPBFB were wheatflour (5000g), water (2950 g), salt (100 g), compressedyeast—Saccharomyces cerevisiae (100g), vegetable short-ening (100g), ascorbic acid (1.5 g) and baking aids—enzyme alpha amylase and emulsifiers (9.56g).

2.2. Experimental procedure

All ingredients were mixed in a dough mixer for 4minat low speed and for 6min at high speed. Doughtemperature was 2971 1C after mixing. After resting for20min at room temperature, the dough was divided,molded into 60 g pieces (3.5 cm diameter and 9.0 cmlength) and proofed at 3471 1C until the volumedoubled. After that, the pieces remained for 15min atroom temperature to dry out the surface before cutting,and were partially baked for 7min in a turbo oven at250 1C with baking steam during the first minute.Immediately after baking, part-baked French breadwas frozen in a Climatic Chamber (Veb Feutron Greiz,model 3522/51, Germany) at �30 1C and 1.5m/s of airspeed. The endpoint of freezing was established whenthe thermocouple inside the core of some piecesindicated �18 1C. Some pieces were completely baked(about 15min) and they were analysed as fresh bread(zero days of storage period).

After freezing, part-baked French bread was packedin polyethylene bags and stored in a freezer at �18 1Cfor 7 days. Daily, samples were removed from thefreezer, thawed at room temperature for 1 h and thentaken to the oven at 250 1C to complete the bakingprocess, about 6min. Again baking steam was appliedduring the first minute.

2.3. Physical analyses

All analyses of French bread were conducted, in fourreplications 1 h after final baking (Carr & Tadini, 2003).Weight was obtained by direct measurement; volumethrough the Bread Volumeter (model 206, CHOPIN,France) and water content was determined according tothe AACC (1995) method.

For the analyses of crumb porosity, the samples werecut in the radial direction as shown in Fig. 1 and

scanned (HP Scan jet 5300C). The contrast between theair and solid phase of the sample was analysed, induplicate, by an image analyser (Leica, Q500MC). Theporosity of the bread crumb was obtained by the ratio ofair and total areas.

2.4. Textural analysis

Texture analysis was carried out 1 h after final baking,in four replications on separate samples, using a textureanalyser SMS, model TA-XT2i (Stable Micro System,England), with a 36mm probe (P/36) and according tothe TPA method (Brennan, 1988; SMS, 2001). Firmness,chewiness, cohesiveness and springiness were calculatedfrom the curves adopting the method described byBrady and Mayer (1985).

The preparation of the samples and TPA wereconducted as described in Carr and Tadini (2003).

2.5. Sensory analyses

Sensory analyses were performed in two steps: in thefirst one, the Difference from Control test was applied todetermine whether a difference existed between theFPBFB sample and control (fresh bread), and toestimate the size of such a difference. Samples werepresented as whole bread for appearance, half-bread fortactile by direct touch and 2-cm slices for mouthfeel, onwhite plastic dishes coded with three-digit randomnumbers and served in a randomized order. In thesecond step, the Consumer Acceptance test was appliedaccording to Meilgaard, Civille, and Carr (1999) tocompare FPBFB with a commercial brand bread.Samples were presented as whole bread for appearance

(surface gloss, roughness of the surface and cut on

surface), half-bread for oral texture (crust crispness andcrumb firmness) and overall flavor, on white plasticdishes coded with three-digit random numbers andserved in a randomized order. The assessments werecarried out in a laboratory equipped with individualbooths under fluorescent light. For Difference fromControl test the analyses were performed for seven days,

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while for Consumer Acceptance test, the sensorialanalysis was performed only once a time.

2.5.1. Difference from Control test

This test was carried out by 33 assessors (15 male and18 female between 20 and 60 years old), who had beenselected by their sensitivity to taste, according to ISO/DIS 3972/1979 (ISO, 1990). All subjects were familiarwith the test format and the meaning of the scale.

The test objective was to determine whether adifference exists between the FPBFB sample and control(fresh French bread) regarding appearance, tactile by

direct touch and mouthfeel, and to estimate the size ofany such differences (five-point scale ranged from‘extreme difference’ to ‘no difference’). Each panelistwas presented with one control and two test sampleswithout informing them that one of the samples iscontrol. Sample scores were evaluated by comparingwith the results obtained from blind control.

2.5.2. Consumer Acceptance test

This test was carried out, at 4-day frozen storage, by87 bread usual consumer volunteers (49 male and 38female, between 17 and 62 years old), students oremployees of the university department. The objective ofthe test was to compare FPBFB studied in this workwith a commercial brand one, regarding appearance,oral texture and overall flavor on a nine-point hedonicscale. The scale of values ranged from ‘like extremely’ to‘dislike extremely’ corresponding to the highest andlowest scores of ‘9’ and ‘1’, respectively. The PurchaseIntent was also evaluated on a five-point scale,‘definitely would buy’ to ‘definitely would not buy’corresponding to the highest and lowest scores of ‘5’ and‘1’, respectively.

2.6. Statistical analyses

ANOVA and two-sample comparison analyses wereperformed in all results using the statistical program

Table 1

Results of physical and textural parameters of frozen part-baked French bre

Parameter Storage period (days)

0 1 2 3

Weight (g) 50.67b 49.13a,b 45.96a 46.79a

Specific volume (cm3/g) 5.21b 4.78a,b 5.10a,b 5.05a,b

Water content (g/100 g) 32.22a 34.36a 32.69a 33.60a

Crumb porosity 0.55a 0.49a 0.54a 0.53a

Firmness (N) 6.24a 6.00%a 6.32a,b 5.38a

Springiness (mm) 18.52a 18.47a 18.26a 18.24a

Cohesiveness 0.67a 0.66a 0.60a 0.61a

Chewiness (mJ) 75.0b 69.8b 65.2a,b 46.4a

Mean values in a row followed by different letters are significantly different

Statgraphics for Windows v4.0, at a confidence intervalof 95%.

3. Results and discussion

3.1. Physical and textural analyses

Table 1 summarizes the physical and textural resultsof the FPBFB according to storage time. Weight,specific volume and crumb porosity of frozen breadwere lower than fresh one (0 days) (see Fig. 2). Specificvolume of FPBFB had a significant decrease after 4 daysof frozen storage compared with those of fresh one.After 2 days of frozen storage, there was also asignificant decrease of FPBFB weight. The valuesobtained in this paper are within those reported byBent (1998) and Carr and Tadini (2003). The lastauthors observed a specific volume reduction of part-baked French bread frozen stored for almost a month.According to them this decrease was mainly observedafter a 7-day storage period and further storage did notproduce great changes.

Barcenas et al. (2004), studying the effect of hydro-colloids on bread quality, observed that bread volume at0 days was in all samples higher than that obtained forfrozen stored samples; that could be attributed to thedifferent freezing treatment, since 0 days samplesunderwent only the prefreezing stage and a partialfreezing, whereas the other samples suffered a completefreezing stage.

Water loss during frozen storage can contribute toshrinkage, but in this work it was not observed becausesteam baking was applied twice, maintaining theamount of water in the product. Although the ANOVAindicated that frozen storage did not significantlyinfluence crumb porosity, it indicated that all FPBFBpresented lower crumb porosity than the fresh one. Thecrumb walls surrounding air space can be damaged byice crystals during storage and consequently reduce

ad according to days of frozen storage

Tukey HSD

4 5 6 7 5%

48.27a 47.62a 48.30a 48.09a 3.19

4.66a,b 4.23a 4.16a 4.46a,b 1.00

32.47a — — 32.23a 1.05

0.53a — — 0.50a 0.17

5.70a 7.54b 6.33a.b 6.47a,b 1.22

18.31a 18.61a 18.65a 18.41a 0.45

0.65a 0.64a 0.63a 0.62a 0.07

65.1a,b 90.0c 72.9b 70.1b 20.9

(Po0:05).

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50.67

49.13

45.96

46.79

48.27

47.62

48.30 48.09

5.21

4.78

5.10 5.05

4.66

4.23 4.16

4.46

44.5

45.5

46.5

47.5

48.5

49.5

50.5

51.5

52.5

53.5

54.5

-1 0 2 4 6 8

Frozen storage (days)

Wei

gh

t (g

)

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

Sp

ecif

ic v

olu

me

(cm

3 /g

)

1 3 5 7

Fig. 2. (}) Weight (g) and (~) specific volume of frozen part-baked French bread, measured after 1 h final baking and related to frozen storage.

L.G. Carr et al. / LWT 39 (2006) 540–547544

porosity. Mandala (2005) reported shrinkage andporosity reduction of frozen baked bread after thawingby microwaves. The specific volume was more than 20%in all samples (control and added with hydrocolloids).

Storage time significantly affected firmness andchewiness of bread; however, differences of springinessand cohesiveness were not significant. A tendency ofdecrease in chewiness and firmness up to the 4th day ofstorage time was observed followed by an increase therest of the time, denoting some change in crumbstructure. These results are comparable to thosereported by Carr and Tadini (2003) and Fik andSurowka (2002). These last authors studied the effectof prebaking and frozen storage on instrumental textureof round-shaped bread for 11 weeks and they alsoverified more pronounced changes in bread quality atthe beginning of the storage period. After 1 week frozenstorage, sensory and textural changes were only slight.Another point of view is that the observed variationscan be due to the non-homogeneous nature of theanalysed material.

Barcenas et al. (2004) verified that the hardness ofbread crumb containing HPMC was not affected byfrozen storage at �25 1C, but this parameter showed aprogressive increase in the control bread with the time offrozen storage.

3.2. Sensory analyses

Table 2 summarizes the results of the Difference fromControl test. Mean sensory scores showed a slightdifference between FPBFB and blind control. Appear-

ance and tactile by direct touch presented a significant

difference after the third day of frozen storage, whilemouthfeel presented significant difference after thesecond day, average between 1.9 (slight difference fromblind control) and 2.6 (between slight and moderatedifference). Fresh bread tactile by direct touch andmouthfeel scores did not present a significant differencerelated to control during the studied period. However,all scores for FPBFB were less than 3.0 (that meansmoderate difference from blind control), indicating thatthe panelists, during the studied period, consideredFPBFB to be similar to fresh bread.

Fik and Surowka (2002) studied the effect ofprebaking and frozen storage on the sensory quality ofbread. Fresh full-baked product was characterized, priorto freezing, by high sensory quality, obtaining a score of31 points out of 32. The process of freezing and 1 weekstorage produced by itself a relatively small change inthe quality, reducing the score by only six points;moreover, from the fifth week of storage onwards thescore remained constant (21 points) until the end ofstorage period.

Mean sensory scores obtained from the ConsumerAcceptance test are shown in Table 3. A cursory look atthe table shows that all mean hedonic scores of FPBFBwere generally high. A two-sample comparison analysiswas performed and Fig. 3 presents frequency histogramscomparing responses of sensory attributes from theConsumer Acceptance test. The frequency of each class(FPBFB—light shade, and commercial brand—darkshade) is represented by a vertical bar whose height isequal to the frequency of responses. In this figure it canbe observed that the frequency of responses of thehighest hedonic scores of all FPBFB sensory attributes

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Table 2

Effect of frozen storage on sensory characteristics of frozen part-baked French bread in comparison with fresh bread

Sensory characteristics Frozen storage period (days) Tukey HSD

1 2 3 4 7 5%

Appearance

Fresh (blind control) 2.570.2b1 1.970.2a,b1 1.770.2a1 1.670.2a1 1.670.2a1 0.7

Frozen 2.570.1b1 1.970.2a1 2.270.2a,b2 2.170.2a,b2 2.570.2b2 0.7

Tactile by direct touch

Fresh (blind control) 2.270.2a1 2.170.2a1 1.670.2a1 1.870.2a1 2.070.2a1 0.7

Frozen 2.670.2a1 2.470.2a1 2.370.2a2 2.470.2a2 2.470.2a2 0.8

Mouthfeel

Fresh (blind control) 2.170.2a1 1.970.2a1 1.770.2a1 2.270.2a1 1.970.2a1 0.7

Frozen 2.570.2a1 2.670.2a2 2.570.2a2 2.070.2a1 2.370.2a1 0.8

Mean values 7s.e. with different superscripts row wise (alphabet) and column wise (numeral) differ significantly (Po0:05).n ¼ 140 no. of responses for sensory parameters.

Means are scores given by 33 judgments on a five-point scale where 1: no difference and 5: extreme difference.

Table 3

Results of laboratory consumer acceptance test of frozen part-baked French bread and a commercial brand

Sensory attributes Frozen part-baked

French bread

Commercial

brand

Tukey HSD, 5%

Verbal hedonic scalea

Appearance

Surface gloss 7.671.2a 4.471.8b 0.5

Roughness of the surface 7.471.2a 4.471.8b 0.5

Cut on the bread surface 6.771.7a 4.671.9b 0.5

Oral texture

Crust crispness 6.871.8a 6.572.0a 0.6

Crumb firmness 7.571.4a 6.671.6b 0.5

Overall flavor 7.471.4a 6.671.7b 0.5

Purchase intent scaleb 5 4 3 2 1

Frozen part-baked French bread 60% 37% 2% 1% 0%

Commercial brand 14% 28% 36% 17% 5%

Mean values 7 s. e. with different superscripts row wise differ significantly (Po0:05). Mean of 87 judgments.aAcceptance scores: 9 ¼ like extremely; 5 ¼ neither like nor dislike; 1 ¼ dislike extremely.bPurchase intent scores: 5 ¼ definitely would buy; 4 ¼ probably would buy; 3 ¼ maybe/maybe not buy; 2 ¼ probably would not buy;

1 ¼ definitely would not buy.

L.G. Carr et al. / LWT 39 (2006) 540–547 545

were high indicating a strong consumer appeal incomparison with those of commercial brand. Theyrepresented an approval percentage (like moderately,

like very much and like extremely scores) between 62.1%and 87.4% in all parameters. Specifically for theappearance attribute, FPBFB had 74% of responsefrequency for surface gloss, 40% for roughness of the

surface and 42% for cut on surface related to like very

much and like extremely scores, while the commercialbrand had 18%, 14% and 14%, respectively. Purchaseintent responses differed significantly as shown in Table3. ‘Definitely would buy’ and ‘probably would buy’scores were higher for FPBFB than for those of thecommercial brand. These results show that appearance

of this kind of bread is an important attribute forconsumer, confirming the preference scores.

4. Conclusion

Frozen part-baked French bread (FPBFB) revealed alower specific volume and weight than fresh bread;however, frozen storage did not influence water content,crumb porosity, springiness and cohesiveness. Resultsobtained from the Difference from Control test showedthat the panelists perceived a slight difference after thethird day between FPBFB and fresh one. Consumer testshows that all mean hedonic scores of FPBFB weregenerally higher than the commercial brand, indicatingthat the appearance of this kind of bread is an importantattribute for consumers. Texture and sensory character-istics of FPBFB stored for a week indicated that theFrench bread studied in this work could be consideredto be quite similar to fresh bread.

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Frozen part-baked French bread

Commercial brand

Fre

quen

cy

Crumb firmness

1 2 3 4 5 6 7 8 935

25

15

5

5

15

25

35

Frozen part-baked French bread

Commercial brand

Fre

quen

cy

Overall flavor

1 2 3 4 5 6 7 8 940

30

20

10

0

10

20

30

40

Frozen part-baked French bread

Commercial brand

Fre

quen

cy

Cut on surface

1 2 3 4 5 6 7 8 935

25

15

5

5

15

25

35

Frozen part-baked French bread

Commercial brand

Fre

quen

cy

Crust crispness

1 2 3 4 5 6 7 8 930

20

10

0

10

20

30

Frozen part-baked French bread

Commercial brand

Fre

quen

cySurface gloss

1 2 3 4 5 6 7 8 94535251555

15253545

Frozen part-baked French bread

Commercial brand

Fre

quen

cy

Roughness of the surface

1 2 3 4 5 6 7 8 94535251555

15253545

Fig. 3. Frequency histograms comparing responses of sensory attributes from Consumer Acceptance test of frozen part-baked French bread (light

shade) and a commercial brand (dark shade). Scores: 1 ¼ dislike extremely; 2 ¼ dislike very much; 3 ¼ dislike moderately; 4 ¼ dislike slightly;

5 ¼ neither like nor dislike; 6 ¼ like slightly; 7 ¼ like moderately; 8 ¼ like very much; 9 ¼ like extremely.

L.G. Carr et al. / LWT 39 (2006) 540–547546

Acknowledgments

To FAPESP (The State of Sao Paulo ResearchFoundation) for the financial support, to FMAIIS Ind.de Alimentos Ltda for the technical support and allvolunteer panelists.

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