8 Oleochemistry Products
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8.3.3.3 EOs as Antifungal Agents
Many literature studies appeared that are focused on the antifungal properties of
essential oils or of their components. These studies [113] reported a generally positive assessment of EOs against different fungi like, for example, Botrytis cinerea,
Monilinia fructicola, Rhizoctonia solani, Fusarium moniliforme and others. As an
example of antifungal action of specific components present in EOs, we can cite
that of thymol and carvacrol that resulted highly active against most fungal species
tested [117, 146]. The action mechanism of these compounds against fungi is still
unknown but the researchers believe that this activity may be very likely related to a
general ability to dissolve or disrupt the integrity of cell walls and membranes (Isman
et al. 2006). In Table 8.2, some examples of antifungal activity of EOs is reported.
A different strategy used to test the effectiveness of EOs against fungi, consists in
treating the soil with a certain amount of plant essential oil and successively check if
the population of fungi and other parasites declines. Some greenhouse experiments
[170] have shown that, for example, by treating the soil with 400–700 mg of oil (thymol, palmarosa and lemongrass oil) per liter of soil inhibit the growth of Ralstonia
solanacearum on tomato plants. After only 7 days, the bacterial population declined
to an undetectable level on 100% of plants.
8.3.4 Essential Oils in Food Applications
It is well known that food products, especially during storage, can undergo numerous
physical, chemical and microbial changes and that the stability of food is a function
of changes occurring in the food components, such as proteins, lipids and carbohydrates. This can be ascribed to processing and environmental factors like exposure to
temperature, light, moisture, etc. The use of a protective barrier during processing,
storage, and handling not only slows down the deterioration of food but may also
enhance its quality. Suitable packaging can retard the deterioration phenomenon and
hence, extend the shelf life of products and this is the main motivation for which,
in recent years, a wide variety of packages have been developed and employed to
provide desirable effects. Examples of this packaging strategy [205], are the incorporation in the polymer matrix, of oxygen, moisture and ethylene scavengers for,
respectively, oxygen, moisture and ethylene sensitive foods; use of carbon dioxide
in other foods; flavour imparting or scavenging chemicals; antimicrobial agents for
microbiological stability of foods.
The concept of direct incorporation of these chemicals and agents directly into the
packaging material is not the only possibility. Other approaches involve the placing
of these active agents on the packaging layer or between this one and the food.
Such strategies for obtaining desirable effects are nowadays referred to as ‘active
packaging,’ ‘interactive packaging’ and ‘intelligent packaging.’
Active packaging is a relatively novel concept developed to provide interaction between food and packaging material, and it aims to extend the product shelf
227
8.3.3.3 EOs as Antifungal Agents
Many literature studies appeared that are focused on the antifungal properties of
essential oils or of their components. These studies [113] reported a generally positive assessment of EOs against different fungi like, for example, Botrytis cinerea,
Monilinia fructicola, Rhizoctonia solani, Fusarium moniliforme and others. As an
example of antifungal action of specific components present in EOs, we can cite
that of thymol and carvacrol that resulted highly active against most fungal species
tested [117, 146]. The action mechanism of these compounds against fungi is still
unknown but the researchers believe that this activity may be very likely related to a
general ability to dissolve or disrupt the integrity of cell walls and membranes (Isman
et al. 2006). In Table 8.2, some examples of antifungal activity of EOs is reported.
A different strategy used to test the effectiveness of EOs against fungi, consists in
treating the soil with a certain amount of plant essential oil and successively check if
the population of fungi and other parasites declines. Some greenhouse experiments
[170] have shown that, for example, by treating the soil with 400–700 mg of oil (thymol, palmarosa and lemongrass oil) per liter of soil inhibit the growth of Ralstonia
solanacearum on tomato plants. After only 7 days, the bacterial population declined
to an undetectable level on 100% of plants.
8.3.4 Essential Oils in Food Applications
It is well known that food products, especially during storage, can undergo numerous
physical, chemical and microbial changes and that the stability of food is a function
of changes occurring in the food components, such as proteins, lipids and carbohydrates. This can be ascribed to processing and environmental factors like exposure to
temperature, light, moisture, etc. The use of a protective barrier during processing,
storage, and handling not only slows down the deterioration of food but may also
enhance its quality. Suitable packaging can retard the deterioration phenomenon and
hence, extend the shelf life of products and this is the main motivation for which,
in recent years, a wide variety of packages have been developed and employed to
provide desirable effects. Examples of this packaging strategy [205], are the incorporation in the polymer matrix, of oxygen, moisture and ethylene scavengers for,
respectively, oxygen, moisture and ethylene sensitive foods; use of carbon dioxide
in other foods; flavour imparting or scavenging chemicals; antimicrobial agents for
microbiological stability of foods.
The concept of direct incorporation of these chemicals and agents directly into the
packaging material is not the only possibility. Other approaches involve the placing
of these active agents on the packaging layer or between this one and the food.
Such strategies for obtaining desirable effects are nowadays referred to as ‘active
packaging,’ ‘interactive packaging’ and ‘intelligent packaging.’
Active packaging is a relatively novel concept developed to provide interaction between food and packaging material, and it aims to extend the product shelf