Micoencapsulation of bioactive plant extracts: a tool to functionalize cottage cheeses
Conference Paper
Overview
Overview
abstract
Foeniculum vulgare Mill. (fennel) and Matricaria recutita L. (chamomile) are two examples of plants
with reported antioxidant and antimicrobial properties, which can be related with their composition in
phenolic compounds [1,2]. Furthermore, according to previous results of our research group, the direct
incorporation of the aqueous extracts showed capacity to maintain the nutritional properties of the cottage
cheeses, up to 7 days of storage, while improving the antioxidant potential. However, after 14 days, a
decrease in the antioxidant properties was observed [1,2], which can be related with factors such as light,
moisture, temperature and pH, that can cause bioactive compounds degradation. Therefore, the aim of the
present study was to prepare microcapsules with the aqueous extracts of fennel and chamomile for
incorporation in cottage cheese samples, in order to protect the bioactive molecules present in the extracts,
such as phenolic compounds, and prevent the decrease of the antioxidant activity observed after the 14
days period. The microspheres were prepared using an atomization/coagulation technique. Sodium
alginate was used as the matrix material to produce the microspheres that were characterized through
optical microscopy (OM), during and after atomization, for inspecting morphology. The encapsulation
efficiency (EE) was determined by HPLC-DAD by an indirect method by analysing the coagulation
solution. FTIR was also used to attest the presence of the extract inside of the alginate matrix. These
microencapsulated extracts were incorporated in cottage cheese samples that were further characterized in
terms of nutritional properties and antioxidant potential right after incorporation, and after 7 and 14 days
of storage at 4•c. The EE was estimated as -100% and the FTIR analysis confirmed the presence of the
extracts inside the microspheres. The results showed that the incorporation of the microencapsulated
extracts did not cause changes in the nutritional value of cottage cheeses (through a comparison with
control samples without extracts). The predominant fatty acids were palmitic (C16:0) and oleic (CI8:0)
acids. The order of abundance of fatty acids was as follows: saturated fatty acids (SF A)> monounsaturatcd
fatty acids (MUF A)> polyunsaturated fatty acids (PUF A). Regarding free sugars, lactose was the only
sugar identified and quantified in all samples. Regarding the antioxidant activity, the samples
functionalized with the microencapsulated extracts showed a higher preservation of this property even
after the 7th day of storage. Overall, the incorporation of the protected plant extracts in dairy foods can be
a strategy to provide health benefits to consumers.
