Lecture: food matrix
What are functional foods?
In the past the food industry was looking to put new products to the market, it was pushed to the
consumer and it did not matter if it was healthy or not. It increased the food-related diseases.
These diseases is the reason why consumers are now looking for healthy food, which drives the
design of food. So, we are looking to functional foods.
Food = the primary role of food is to provide sufficient nutrients to meet the nutritional requirements
of an individual.
Functional food = something that gives you a bit more than only nutrition, it possesses advantageous
physiological effects. It needs to be a food product (e.g. no capsule or pill). In general, functional
foods have 3 characteristics:
- Nutritional function
- Health benefit
- Technological process mediated the production or the delivery of the functional ingredients
Food matrix
Food matrix = the part of the microstructure of foods, usually corresponding to a physical and spatial
domain that contains, interacts directly and/or gives a particular functionality to a constituent (e.g. a
nutrient) or element of the food (e.g. starch granules, microorganisms). It is known that food matrix
plays a role in a lot of things. For instance, the matrix affects the way how we digest food, the way
we extract nutrients.
The types of food matrices are:
- Liquids
o Aqueous: water-based
o Emulsion: mixture of oil and water
- Gels
o Firm
o Viscoelastic
- Solid/semi-solid
o Cellular and exocellular
o Fibrous
o Dense
, o Porous (foams)
Macrostructure vs. microstructure
- Macrostructure = refers to the whole food product and its sensory and rheological
properties that can be measured and tasted. Identifying food is with the use of
macrostructures.
- Microstructure = is composed of rather a limited variety of structural elements. Such as
droplets and other elements in cells. Microstructures provide the macrostructure of food.
Particles can aggregate which creates polymers, it becomes more complex and creates networks or
are absorbed together with other structures to create a specific food matrix. In emulsions you have
oil droplets that are surrounded with proteins that homogenizes the droplets within the water that
they are in emulsified. So, different particles create connections with each other to try to create a
structure which is stable for the food product.
Food matrix structural elements:
- Water droplets: important in emulsion type food (e.g. margarine, butter, low-fat spreads).
The water droplets are stabilized by emulsifiers such as monoglycerol and licitins or bi-solid
particles such as fat crystals. The droplet size is going to influence the way how we perceive
the food products, the sensory properties. In sandwich spreads the droplets should be small.
- Oil droplets: structural elements in ice cream, mayonnaise etc. The droplets can be stabilized
by some proteins and carbohydrates that are able to keep them together but without joining
to create bigger droplets by breaking up the surfaces. The size and homogeneity of these fat
droplets also affect the sensory properties, they give a smooth taste when properly
homogenized.
- Gas cells: important and present in many foods (e.g. ice cream, beer, bread, cake etc.). In
some cases foods have a higher quality with some high amount of gas cells. The foam
stability will depend on many factors such as the matrix that is mobilized in the air, because if
the air goes out you lose the structure. In bread this is the gluten network which is formed. In
other cases it can be other solid matrices.
- Strands: in many food systems such as gels, bread. There are several types of strand
formation, such as aggregation of proteins and polysaccharides.
- Fat crystals: can be present in spreads, this is because triglycerides have a high melting
points. They do not occur in single crystals but have different forms of aggregations,
What are functional foods?
In the past the food industry was looking to put new products to the market, it was pushed to the
consumer and it did not matter if it was healthy or not. It increased the food-related diseases.
These diseases is the reason why consumers are now looking for healthy food, which drives the
design of food. So, we are looking to functional foods.
Food = the primary role of food is to provide sufficient nutrients to meet the nutritional requirements
of an individual.
Functional food = something that gives you a bit more than only nutrition, it possesses advantageous
physiological effects. It needs to be a food product (e.g. no capsule or pill). In general, functional
foods have 3 characteristics:
- Nutritional function
- Health benefit
- Technological process mediated the production or the delivery of the functional ingredients
Food matrix
Food matrix = the part of the microstructure of foods, usually corresponding to a physical and spatial
domain that contains, interacts directly and/or gives a particular functionality to a constituent (e.g. a
nutrient) or element of the food (e.g. starch granules, microorganisms). It is known that food matrix
plays a role in a lot of things. For instance, the matrix affects the way how we digest food, the way
we extract nutrients.
The types of food matrices are:
- Liquids
o Aqueous: water-based
o Emulsion: mixture of oil and water
- Gels
o Firm
o Viscoelastic
- Solid/semi-solid
o Cellular and exocellular
o Fibrous
o Dense
, o Porous (foams)
Macrostructure vs. microstructure
- Macrostructure = refers to the whole food product and its sensory and rheological
properties that can be measured and tasted. Identifying food is with the use of
macrostructures.
- Microstructure = is composed of rather a limited variety of structural elements. Such as
droplets and other elements in cells. Microstructures provide the macrostructure of food.
Particles can aggregate which creates polymers, it becomes more complex and creates networks or
are absorbed together with other structures to create a specific food matrix. In emulsions you have
oil droplets that are surrounded with proteins that homogenizes the droplets within the water that
they are in emulsified. So, different particles create connections with each other to try to create a
structure which is stable for the food product.
Food matrix structural elements:
- Water droplets: important in emulsion type food (e.g. margarine, butter, low-fat spreads).
The water droplets are stabilized by emulsifiers such as monoglycerol and licitins or bi-solid
particles such as fat crystals. The droplet size is going to influence the way how we perceive
the food products, the sensory properties. In sandwich spreads the droplets should be small.
- Oil droplets: structural elements in ice cream, mayonnaise etc. The droplets can be stabilized
by some proteins and carbohydrates that are able to keep them together but without joining
to create bigger droplets by breaking up the surfaces. The size and homogeneity of these fat
droplets also affect the sensory properties, they give a smooth taste when properly
homogenized.
- Gas cells: important and present in many foods (e.g. ice cream, beer, bread, cake etc.). In
some cases foods have a higher quality with some high amount of gas cells. The foam
stability will depend on many factors such as the matrix that is mobilized in the air, because if
the air goes out you lose the structure. In bread this is the gluten network which is formed. In
other cases it can be other solid matrices.
- Strands: in many food systems such as gels, bread. There are several types of strand
formation, such as aggregation of proteins and polysaccharides.
- Fat crystals: can be present in spreads, this is because triglycerides have a high melting
points. They do not occur in single crystals but have different forms of aggregations,
