USE OF GRAPE SKIN FLOUR FOR NOVEL FOOD DEVELOPMENT:

SENSORY CHARACTERIZATION AND ACCEPTABILITY OF SOFT CHEESES

Maria PIOCHI1, Luisa TORRI1, Roberta MARCHIANI2, Giuseppe ZEPPA2, Erminio MONTELEONE3

SENSORY CHARACTERIZATION AND ACCEPTABILITY OF SOFT CHEESES

Maria PIOCHI , Luisa TORRI , Roberta MARCHIANI , Giuseppe ZEPPA , Erminio MONTELEONE1University of Gastronomic Sciences, Italy; 2University of Turin, Italy; 3University of Florence, Italy

INTRODUCTION METHODSINTRODUCTIONGrape skin flours (GSF) have been recently proposed as functional ingredient in order to create novel

foods with enhanced nutritional value and minimize the volume of agricultural wastes (1). Despite their

interesting nutritional properties (i.e. for fiber and antioxidants content), new developed products are

METHODSFree Choice Profile� 22 expert cheese tasters (M=14; aged from 24 to 70, mean age=55) from

the Italian National Cheese Taster Association (ONAF, Organizzazione

1

AIM

interesting nutritional properties (i.e. for fiber and antioxidants content), new developed products are

often critical in terms of sensory acceptability and their success by consumers is therefore under risk (2).the Italian National Cheese Taster Association (ONAF, Organizzazione

Nazionale Assaggiatori Formaggio).

� One evaluation session (around 120 minutes).

� Two sample sets were provided:AIMThe aims of this study were to:

1. investigate the sensory properties for new cheese prototypes obtained by addition of GSF

2. investigate consumers’ responses for the innovative cheeses

The effects of the grape variety and different percentages of GSF addition were studied.

� Two sample sets were provided:

1st set -> Free generation of attributes.

2ndset -> Intensity quantification of selected attributes (9-point scale:

1=extremely weak, 9=extremely intense).

Data Analysis: Generalized Procrustes Analysis (GPA) (Senstools v. 1.2x OP&PThe effects of the grape variety and different percentages of GSF addition were studied.

SAMPLES BarberaChardonnay

1=extremely weak, 9=extremely intense).

Data Analysis: Generalized Procrustes Analysis (GPA) (Senstools v. 1.2x OP&P

Product Research BV, Utrecht, Netherlands).

Consumer test2SAMPLES� Grape skin flours (average particle size: 250 μm) were

added to cow’s milk curd.

Soft cheeses were aged 1 week.

� Grape variety: Barbera (B), Chardonnay (C)

B0.8

Barbera

C0.8

ChardonnayConsumer test� 90 consumers (M=43; aged from 8 to 70, mean age=43)

� Central Location Test at the International Cheese Exhibition (Cheese

2013, Bra - Italy).

2

� Grape variety: Barbera (B), Chardonnay (C)

� Percentages of GSF addition: 0.8, 1.6, and 2.4%

� 7 samples: B0.8, B1.6, B2.4, C0.8, C1.6, C2.4, STD.

B1.6C1.62013, Bra - Italy).

� Liking test: appearance, odour, taste, flavour, texture, overall liking

(1=extremely dislike, 9=extremely like).

� Questionnaire

Data Analysis: were analyzed by 2-way mixed ANOVA models followed bySTD B2.4C2.4

Questionnaire

Data Analysis: were analyzed by 2-way mixed ANOVA models followed by

LSD Fisher’s post–hoc test (SYSTAT vers 13.1, Systat Software Inc, San José,

USA)

RESULTS AND DISCUSSION

111

1a 1b

Appearance and texture Odour, taste, mouthfeel, flavour

Fig. 1 Consensus maps obtained from General

Procrustes Analysis (GPA) considering two matricesastringent_8

f-toasted_12

o-yogurt_13

f-yogurt_17f-yogurt_22

o-yogurt_22

B0.80.6

0.8granular_7crumbly_9

gummy_11

elastic_14

watery_3

0.6

0.8

1a 1bProcrustes Analysis (GPA) considering two matrices

appearance and texture (1a) and odour, taste and

flavour (1b). Individual configurations and sample’s

positioning are depicted. Letters o- and f- : odour

and flavour.

o-lactic_1o-lactic_2

f-whey_3

o-yogurt_3

f-metallic_7sour_8

o-lactic_9

astringent_10f-grassy_12

f-toasted_12

o-fresh_butter_14

f-nuts_15

sweet_16o-cereal_16

f-yogurt_17

f-cream_21

f-yogurt_22B0.8

0.4

0.6

marbling_violet_2

elastic_2

compact_5

marbling_violet_8 gummy_8

white_10floury_10 white_11

marbling_violet_11

compact_11holes_12

marbling_brown_1

4

elastic_14

marbling_brown_1

7

gummy_20

granular_20

marbling_violet_21 elastic_1sticky_19

B0.8B2.40.4

0.6and flavour.

SENSORY PROPERTIESNew developed cheeses were freely

described by experts considering

f-lactic_1

f-cream_3

o-yogurt_3

o-fruity_9 o-wine_10

bitter_11f-animal_13

sour_14

bitter_14

o-fresh_butter_14

o-lactic_15

f-lactic_16sweet_16

o-cereal_16

f-milk_19o-milk_19f-vanilla_21

o-yogurt_21

B2.4C2.4

0.2

marbling_violet_2

white_5homogenous_5elastic_5

compact_5

adhesive_6

sandy_6

elastic_7

marbling_violet_11

marbling_brown_1

1

adhesive_12

4

granular_14

soluble_14doughy_14

granular_18

marbling_20adhesive_21

white_22

homogeneous_3

STD0.2

described by experts considering

appearance, odour, taste, flavour and

texture.

Attributes: 64 from free generation,

sour_2f-milk_3

f-cream_3

f-acetic_3f-citric_3

salty_3

o-vinasse_3o-cereal_3

intensity_flavour_4

salty_4

o-grassy_4bitter_6

f-lemon_7o-fruity_9

o-fruity_10

o-varnish_12

f-winey_13sour_13

bitter_14o-lactic_15o-nuts_17

o-yogurt_17

sweet_19

salty_19

f-ammonia_20

f-vanilla_21

sour_21

sour_22

B1.6

B2.4C2.4

STD

-0.2

0

Dim

2

marbling_brown_2

elastic_7

marbling_brown_9

doughy_12

granular_14

gummy_14

white_17

soluble_17

gummy_18

white_20

holes_20

adhesive_20white_21

B1.6

C0.8

-0.2

0

Dim

2

Attributes: 64 from free generation,

56 after the vocabulary harmonization.

The individual configurations were

salty_3salty_4

sour_10

o-winy_11

f-lactic_12

o-varnish_12

f-alcohol_13

bitter_13

salty_15f-nuts_18

sweet_19

f-yogurt_20

o-yogurt_20

sour_22

C0.8

C1.6

-0.4

-0.2holes_4

not_uniformity_col

or_4

white_6

marbling_brown_6

marbling_brown_7

floury_7

marbling_brown_9

doughty_9

holes_ 14

white_17

homogeneous_mar

bling_18

marbling_18white_20

homogeneous_dou

gh_20

soft_20

C2.4-0.4

-0.2

The individual configurations were

submitted to Generalized Procrustes

Analysis (GPA) applied to two separate

matrices: appearance-texture (Fig. 1a)

and odour-taste-flavour (Fig. 1b).

sweet_2sour_3

bitter_3

o-alcohol_3

f-yogurt_5

f-cream_9

spicy_13

bitter_13

salty_17

f-yogurt_20

salty_20 spicy_21

o-citric_21

-0.6

or_4

doughy_4holes_7

floury_7

compact_9granular_11 gummy_17

bling_18gh_20

gummy_21

gummy_22

C1.6C2.4

-0.6

and odour-taste-flavour (Fig. 1b).

Permutation Tests indicated the

significance of the GPA results (p < 0.05)

f-lactic_2

f-yogurt_5f-yogurt_7

astringent_7o-yogurt_7spicy_15

sour_17bitter_17 f-yogurt_19

sweet_20

-1

-0.8

sandy_4

adhesive_11sandy_11creamy_20

creamy_3

-1

-0.8

significance of the GPA results (p < 0.05)

for both matrices.

� Samples were mainly discriminated according to the % of GSF on PC1 and to grape variety on PC2.

-1

-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1

Dim 1

-1

-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1

Dim 1

� Samples were mainly discriminated according to the % of GSF on PC1 and to grape variety on PC2.

� The increase of % was generally associated to an increase in perceived sourness, saltiness, astringency, marbling aspect, granularity and adhesiveness. Furthermore it contributed to generate several vegetable

sensations (o-winy, o-fruity, o-citric, o-grassy, o-vinasse, o-spicy, f-whey, f-nuts and f-spicy).

� Appearance: violet and brown marbling were generally characteristic attributes for samples prepared with Barbera GSF.

8

9

Cl 1 Cl 2

CONSUMER PREFERENCES� Factor grape variety -> no significant

A K-means Cluster Analysis was conducted on overall liking of 90 consumers:

- Un-paired t-test indicated significant differences between clusters for all

2

6

7

8 Cl 1 Cl 2

AB A

BC BC C BC

� Factor grape variety -> no significant

effect on overall liking of 90 consumers.

� Factor GSF percentage -> a significant

effect on overall liking:

- Un-paired t-test indicated significant differences between clusters for all

samples (p<0.01) -> Cl1: higher preference for all prototypes.

� Cluster 1 (n=54, 60%): a significant effect of product on liking was found for

the appearance, the taste, the flavour and the overall liking � high

5

6

Ove

rall

lik

ing

BC BC C BC

abab

bc

a

a

effect on overall liking:

- the lowest amount of GSF (0.8%) -> the

most liked

- liking proportionally decreased with the

the appearance, the taste, the flavour and the overall liking � high

discrimination

� Cluster 2 (n=36, 40%): a significant effect of product was just found for the

3

4

Ove

rall

bcc- liking proportionally decreased with the

increase of the amount of GSF.

� Factor product (7 samples) -> a

significant effect on liking for appearance,

� Cluster 2 (n=36, 40%): a significant effect of product was just found for the

appearance and the overall liking � low discrimination

Cluster characterization:

A significant cluster*product effect was found, with Cl1 rating the overall liking

1

2

B0.8 B1.6 B2.4 C0.8 C1.6 C2.4

significant effect on liking for appearance,

odour, taste, flavour, texture and the

overall liking.

The control sample was the significantly

A significant cluster*product effect was found, with Cl1 rating the overall liking

for the products higher than Cl2. This difference in liking could be partially

influenced by the higher frequency of cheese consumption declared by Cl1.

No differences for gender, educational qualification and profession was found

Fig. 2. Mean values and standard errors for overall liking of Cl1 and Cl2. Two-way mixed ANOVA models were

separately conducted on liking data of clusters. LSD (p<0.05) letters: block letters for Cl1, Italic letters for Cl2.

B0.8 B1.6 B2.4 C0.8 C1.6 C2.4The control sample was the significantly

most liked sample (6.39±0.17).

No differences for gender, educational qualification and profession was found

between clusters.

3RELATIONSHIP BETWEEN SENSORY PROPERTIES AND CONSUMER RESPONSES

� The key sensory drivers resulted: white colour, homogeneity of appearance and texture, lactic flavours (o-milk, o-lactic, f-lactic, f-cream), sweetness, gummy, compact and elastic texture.

� The most preferred samples showed a less intense sourness, astringency and bitterness.

� Results highlighted the importance of reducing sandiness and granular sensations. Violet and brown marbling, characteristic for B2.4 and B1.6 samples, resulted not particularly appreciated.

CONCLUSIONS� The use of GSF in developing soft cheeses provided satisfactory results.

� A future use in dairy product seems possible. Nevertheless, an optimization of the innovative

REFERENCES(1) Yu, J., & Ahmedna, M. (2013). Functional components of grape pomace: their composition, biological

properties and potential applications. International Journal of Food Science and Technology, 48, 221–� A future use in dairy product seems possible. Nevertheless, an optimization of the innovative

product is required, especially aimed to reduce the flour particle size below the perception threshold

and to improve the flour dispersion.

� Furthermore, investigating the effect of information (GSF enrichment) on consumer’s perception

properties and potential applications. International Journal of Food Science and Technology, 48, 221–

237.

(2) Tourila, H. (2007). Sensory perception as a basis for food acceptance and consumption. In H. Mac Fie,

(Ed.), Consumer-led Food Product Development (pp 34-80). Cambridge: Woodhead Publishing.� Furthermore, investigating the effect of information (GSF enrichment) on consumer’s perception

could represent a future issue.

(Ed.), Consumer-led Food Product Development (pp 34-80). Cambridge: Woodhead Publishing.

AKNOWLEDGEMENTSThis research was supported by AGER (contract number 2010-2222).

EuroSense 2014: A Sense of Life. 7-10 September 2014, 6th European Conference on Sensory and Consumer Research. Bella Center, Copenhagen, Denmark

This research was supported by AGER (contract number 2010-2222).