2.1 Case of study 1a, 1b, and 1c: Influence of storage conditions (temperature, packaging material, and volume of packaging) on the time evolution of a red wine over a storage period of 12 months

The red wine (Table 2) was packed in different packaging materials at the same time in a commercial winery bottling line using a fully automated bottling/filling station, as described in Figure 1.


#### Table 2.

Color is one of the most important organoleptic characteristics of red wines and affects the quality evaluation of the product [45]. Anthocyanins (Ant) are the most important molecules responsible of the young red wines' color. The color change from red-purple to brick-red hues is strongly related to the concentration of

The same experimental approach reported above to describe TSO2 time evolution can be also followed to describe the time evolution of total anthocyanin concentration (TAnt) that may represent a second index of oxidative degradation of

As polyphenols are widely known to play a protective action on the organism against cardiovascular and degenerative diseases [47], the moderate consumption of wine, especially red and rosé ones, has been associated with the reduction of mortality caused by many chronic diseases, a phenomenon that is commonly known as the "French paradox" [48]. In this context, the health properties of wines have been mainly interpreted on the basis of the antioxidant properties of the flavonoid fraction, which are related to both free radical scavenging and transition

In the field of sensory science, sensory analysis was initially adopted as a tool for

In this context, it is possible to introduce the "sensory shelf life" concept of a product [53]. This can be defined as the storage time at which overall quality, or the intensity of a specific sensory attribute, reaches a predetermined value or "failure criterion," assuming that once the product has reached this point, it is no longer

As a function of specific characters, sensory analysis should also be performed in parallel with microbiological and/or chemical-physical shelf life analysis to monitor the sensory profile of the product for potential deleterious sensory attribute changes [53]. Thus, sensory variables used during sensory shelf life testing could include the monitoring of specific sensory attributes related to visual, aroma, and taste attri-

As reported by Jackson [55], most sensory changes that negatively affect wine shelf life are those associated with oxidation and hydrolysis of esters. Such changes are involved in reduction, polymerization, structural rearrangement, and volatility modifications; their relative importance depends on wine style, production techniques, varietal origin, storage conditions, and consumer expectation [55].

With the aim to better understand the time evolution of wines during bottle aging as a function of storage conditions, among the literature available on the topic, we selected and discussed two real case reports recently developed by our

quality control [50]. Since then, it has evolved in one of the most diffused and sophisticated toolkits, allowing to achieve an exhaustive description of the characteristics of the products [51]. According to Stone et al. [52], "Sensory evaluation is a scientific discipline used to evoke, measure, analyze and interpret reactions referable to those characteristics of products as they are perceived by the senses of sight,

oxygen present in the stored wine [46].

Advances in Grape and Wine Biotechnology

the product as a function of packaging.

metal chelating mechanisms [49].

1.4.3 Sensorial evolution of stored wine

smell, taste, touch, and hearing" [50].

2. Experimental evidences

group (Figure 1; Table 2).

214

butes which can be used as indices of sensory quality.

saleable [54].

1.4.2 Chemical evolution of stored wine: Antioxidant capacity

Initial chemical composition of the red wine.

## 2.1.1 Case of study 1a: Influence of storage temperature

As reported in Table 3, after 12 months of storage, it can be observed that the aging of red wine was significantly delayed at the lowest temperature, regardless of the packaging solution adopted. The only exception was represented by the wine stored in glass bottles closed by natural corks [56].


#### Table 3.

TSO2 degradation constant (kTSO2) and initial total SO2 concentration [TSO2]t=0 as a function of storage temperature (time = 12 months). Each sample was identified by code letter ranging from A/a to E/e as described in Figure 1.

in wines stored at room temperature (T = 20 1°C) and in small containers. Among all the parameters evaluated, the concomitance of these two conditions together led

Kinetic parameters describing the time evolution of TSO2 concentration as a function of the packaging used during storage (small volume packages, T = 20°C, storage time = 12 months). Each sample was identified by

) [TSO2]t=0 (mg L<sup>1</sup>

\* 106.8<sup>a</sup>

Main Operating Conditions That Can Influence the Evolution of Wines during Long-Term Storage

b 0.068c 105.7a 0.95 c 0.069c 105.3<sup>a</sup> 0.93 d 0.059<sup>d</sup> 106.2<sup>a</sup> 0.98 e 0.082<sup>a</sup> 105.5a 0.98

\*In each column, the values labeled with different superscript letters show statistically significant differences

) r<sup>2</sup>

\* 0.97

As reported in Table 5, the oxidative degradation occurring in the red wine stored in containers at room temperature (T = 20 1°C) for 12 months was strongly dependent on the packaging, being the TSO2 degradation rate

In particular, in the wine stored in Tetra Brik®, the reduction of TSO2 concentration occurred at a faster rate compared to the wine in glass bottles, independently of the closure. This result may be explained with the fact that glass protected wine from oxidative reactions better than the multilayer material. As regards the clo-

sures, the lowest TSO2 degradation rate was observed with screw caps.

Table 6 shows the main sensorial parameters evaluated in the red wines contained in various packages during storage in order to follow the development during time of the organoleptic characteristics. Apart from the closure, after 12 months the wine stored in glass bottles presented high values for the positive sensorial attributes "frankness," "harmony of odor," and "overall pleasantness." On the contrary, the wine stored in Tetra Brik® showed a worsening of the organoleptic

characteristics, with high values for "degree of oxidation" and "aftertaste."

flavor as a function of the storage conditions, suggesting that their rational

a 4.8<sup>a</sup> 3.7ab 4.2ab 3.3ab 4.8a b 4.3ab 4.5ab 5.3a 3.7ab 4.5<sup>a</sup> c 3.7ab 4.8ab 5.3a 2.3b 4.5<sup>a</sup> d 3.8ab 4.5ab 4.8ab 4.2ab 4.8a e 4.8<sup>a</sup> 1.8<sup>b</sup> 2.0<sup>b</sup> 6.3<sup>a</sup> 1.0<sup>b</sup>

\*In each column, the values labeled with different superscript letters show differences statistically significant

The results show how the characteristics of packaging affect wine bouquet and

Sample Degree of oxidation Frankness Harmony of odor Aftertaste Overall pleasantness

Sensorial evolution of red wine as a function of the packaging used during storage (small volume packages, T = 20 1°C, storage time = 12 months). Each sample was identified by code letter ranging from A/a to E/e as

\* 6.0<sup>a</sup> 4.7ab 2.2<sup>b</sup> 3.8<sup>a</sup>

2.1.4 Conclusions related to case of study 1a, 1b, and 1c

Wine at starting time 0.7<sup>b</sup>

(P < 0.05).

Table 6.

217

described in Figure 1.

to a faster degradation.

(P< 0.05).

Table 5.

Sample kTSO2 (months<sup>1</sup>

DOI: http://dx.doi.org/10.5772/intechopen.85672

code letter ranging from A/a to E/e as described in Figure 1.

a 0.073<sup>b</sup>

statistically significant.

2.1.2 Case of study 1b: Influence of volume (two volumes for each packaging) on the chemical evolution of stored wine

As shown in Table 4, after 12 months of storage, it can be observed that the TSO2 degradation rate significantly increased when the volume of the container decreased, regardless of the packaging solution used. In this case, the only exception was represented by the wine stored in glass bottles closed with screw caps.


\*Within the same sample, values with different letters are significantly different (P < 0.05). Samples represented with upper case letters refer to samples stored in packages with larger volume.

#### Table 4.

TSO2 degradation constant (kTSO2) and initial total SO2 concentration [TSO2]t=0 as a function of package volume (T = 20 1°C, storage time = 12 months). Each sample was identified by code letter ranging from A/a to E/e as described in Figure 1.

## 2.1.3 Case of study 1c: Influence of the packaging material (glass bottles provided with different closures, bag-in-box containers and Tetra Brik®) on the chemical and sensorial evolution of stored wine

As evidenced in Tables 3 and 4, the effects of packaging on both SO2 degradation (Table 5) and sensorial characteristics (Table 6) were investigated during time Main Operating Conditions That Can Influence the Evolution of Wines during Long-Term Storage DOI: http://dx.doi.org/10.5772/intechopen.85672


\*In each column, the values labeled with different superscript letters show statistically significant differences (P< 0.05).

#### Table 5.

2.1.2 Case of study 1b: Influence of volume (two volumes for each packaging) on the

\*Within the same sample, values with different letters are significantly different (P < 0.05).

A (T = 4 1°C) 0.052<sup>a</sup> 106.8 0.96 B (T = 20 1°C) 0.060<sup>a</sup> 105.7 0.97 B (T = 4 1°C) 0.054<sup>b</sup> 105.7 0.82 C (T = 20 1°C) 0.053<sup>a</sup> 105.3 0.96 C (T = 4 1°C) 0.045<sup>b</sup> 105.3 0.81 D (T = 20 1°C) 0.061<sup>a</sup> 106.2 0.93 D (T = 4 1 °C) 0.052<sup>b</sup> 106.2 0.82 E (T = 20 1 °C) 0.070<sup>a</sup> 105.5 0.96 E (T = 4 1 °C) 0.043b 105.5 0.70

was represented by the wine stored in glass bottles closed with screw caps.

a 0.073<sup>a</sup> 106.8 0.97 B 0.060<sup>b</sup> 105.7 0.97 b 0.068<sup>a</sup> 105.7 0.95 C 0.053<sup>b</sup> 105.3 0.96 c 0.069<sup>a</sup> 105.3 0.93 D 0.061<sup>a</sup> 106.2 0.93 d 0.059<sup>a</sup> 106.2 0.98 E 0.070<sup>b</sup> 105.5 0.96 e 0.082a 105.5 0.98 \*Within the same sample, values with different letters are significantly different (P < 0.05). Samples represented with upper case

As shown in Table 4, after 12 months of storage, it can be observed that the TSO2 degradation rate significantly increased when the volume of the container decreased, regardless of the packaging solution used. In this case, the only exception

TSO2 degradation constant (kTSO2) and initial total SO2 concentration [TSO2]t=0 as a function of storage temperature (time = 12 months). Each sample was identified by code letter ranging from A/a to E/e as

) [TSO2]t=0 (mg L<sup>1</sup>

\* 106.8 0.95

) [TSO2]t=0 (mg L<sup>1</sup>

\* 106.8 0.95

) r<sup>2</sup>

) r<sup>2</sup>

2.1.3 Case of study 1c: Influence of the packaging material (glass bottles provided with different closures, bag-in-box containers and Tetra Brik®) on the chemical and

TSO2 degradation constant (kTSO2) and initial total SO2 concentration [TSO2]t=0 as a function of package volume (T = 20 1°C, storage time = 12 months). Each sample was identified by code letter ranging from A/a

As evidenced in Tables 3 and 4, the effects of packaging on both SO2 degradation (Table 5) and sensorial characteristics (Table 6) were investigated during time

chemical evolution of stored wine

Sample kTSO2 (months<sup>1</sup>

A (T = 20 1°C) 0.056<sup>a</sup>

Advances in Grape and Wine Biotechnology

Sample kTSO2 (months<sup>1</sup>

A 0.056<sup>b</sup>

sensorial evolution of stored wine

letters refer to samples stored in packages with larger volume.

Table 4.

216

Table 3.

described in Figure 1.

to E/e as described in Figure 1.

Kinetic parameters describing the time evolution of TSO2 concentration as a function of the packaging used during storage (small volume packages, T = 20°C, storage time = 12 months). Each sample was identified by code letter ranging from A/a to E/e as described in Figure 1.

in wines stored at room temperature (T = 20 1°C) and in small containers. Among all the parameters evaluated, the concomitance of these two conditions together led to a faster degradation.

As reported in Table 5, the oxidative degradation occurring in the red wine stored in containers at room temperature (T = 20 1°C) for 12 months was strongly dependent on the packaging, being the TSO2 degradation rate statistically significant.

In particular, in the wine stored in Tetra Brik®, the reduction of TSO2 concentration occurred at a faster rate compared to the wine in glass bottles, independently of the closure. This result may be explained with the fact that glass protected wine from oxidative reactions better than the multilayer material. As regards the closures, the lowest TSO2 degradation rate was observed with screw caps.

Table 6 shows the main sensorial parameters evaluated in the red wines contained in various packages during storage in order to follow the development during time of the organoleptic characteristics. Apart from the closure, after 12 months the wine stored in glass bottles presented high values for the positive sensorial attributes "frankness," "harmony of odor," and "overall pleasantness." On the contrary, the wine stored in Tetra Brik® showed a worsening of the organoleptic characteristics, with high values for "degree of oxidation" and "aftertaste."

#### 2.1.4 Conclusions related to case of study 1a, 1b, and 1c

The results show how the characteristics of packaging affect wine bouquet and flavor as a function of the storage conditions, suggesting that their rational


\*In each column, the values labeled with different superscript letters show differences statistically significant (P < 0.05).

#### Table 6.

Sensorial evolution of red wine as a function of the packaging used during storage (small volume packages, T = 20 1°C, storage time = 12 months). Each sample was identified by code letter ranging from A/a to E/e as described in Figure 1.

optimization, based on experimental data, could improve the shelf life of wine and enhance the consumer's enjoyment during tasting.

Among all the experimental conditions, the rate of wine aging was higher when the volume of the containers decreased and storage temperature increased. Furthermore, after 12 months of storage, glass bottles generally better preserved wine from oxidation than multilayer materials, regardless of the closure characteristics.

To highlight the fact that the rate of TSO2 degradation may represent a chemical index of the aging degree of the red wine during storage, the TSO2 degradation kinetic constant (Table 5) was correlated for all packaging conditions with the sensory attributes (see Table 6). The correlation coefficients are reported in Table 7.


#### Table 7.

Correlation matrix relating the kinetic constant describing TSO2 degradation to wine attributes (storage time = 12 months; T = 20°C; small volume packages).

According to Paula and Conti-Silva [57], a correlation coefficient of about 0.70 indicates a fairly strong correlation. Thus, data reported for this case of study evidenced that the TSO2 degradation rate (kTSO2) is strongly inversely correlated to positive sensorial attributes such as "frankness" and "harmony of odor" as well as the hedonic parameter "overall pleasantness," whereas the negative attribute "degree of oxidation" is directly correlated with kTSO2.

Based on the above observations, an integrated approach deriving from the merging of both chemical and sensorial data can be used to identify the best packaging and storage conditions necessary to extend the shelf life of red wines. In this context, kTSO2 represents a useful index to describe the chemical evolution of red wines in combination with the main sensorial attributes generally associated with oxidative evolution.

The preliminary results obtained after 12 months of storage indicate that wine evolution during storage could be greatly influenced by the packaging characteristics (i.e., materials and volumes). Furthermore, also temperature imposed during the storage period seems to play a key role in the evolution of wine, since it can directly influence the oxygen permeability of the system "wine + package."
