The new review, published in the journal Trends in Food Science & Technology, summarises state of the art lipid based carrier technologies including nanoemulsions, nanoliposomes, solid lipid nanoparticles and a novel generation of encapsulation system known as nanostructure lipid carriers – investigating the differences in physicochemical properties, and the potential advantages and limitations of the delivery mechanisms for the food industry.
The reviewers said that despite the different advantages of carbohydrate and protein based nanocapsules, such systems do not have the potential to fully scale up to industrial levels – because of the need to apply “complicated chemical or heat treatments which cannot be completely controlled.”
“On the other hand, lipid based nanocarriers have possibility of industrial production and bear advantage of more encapsulation efficiency and low toxicity,” said the researchers, led by Dr Milad Fathi from the Ferdowsi University of Mashhad, Iran.
They explained that applying nanoparticles and nanostructure lipid carriers to food systems “have considerable advantages” over conventional encapsulation systems – including higher stability, longer release time and a sustained release profile.
“Future trends in nanodelivery systems should focus more on investigations pertaining to the physicochemical properties of the nanocarriers as well as the properties and interactions of food systems incorporating nanoencapsulated bioactives,” they added.
Nano-potential
The reviewers said that in recent years nanotechnology has found “innumerable applications” in different food industries. Among the most promising, they note, is the use of nanocariers as a delivery system for food ingredients.
The authors explained that nanoencapsulation technologies allow the protection of sensitive food ingredients from unfavourable conditions, whilst also eradicating incompatibilities between ingredients. Fathi and his team explained that nanocarriers provide more surface area “and have the potential to enhance solubility, improve bioavailability and ameliorate controlled release and targeting of the encapsulated food ingredients, in comparison to micro-size carriers.”
They said that food applicable nanocarrier systems are typically produced from carbohydrate, protein or lipid.
“Despite the strong upsurge in the investigations of nano-delivery systems and proven role of nanoencapsulation in enhancing bioavailability, solubility and protection of food ingredients, there is no comprehensive information on different aspects of lipid-based nanocarriers,” added the researchers.
Lipid delivery
Fathi and his colleagues explained that because of their ability to improve bioactive solubilisation and potential for enhancing absorption in the gastrointestinal tract, nanoemulsions are good candidate for the delivery of poorly water-soluble food ingredients, including fish oil and lipophilic vitamins.
They noted that nanoliposomes – also known as lipid vesicles – can be tailored to deliver and release their load in the target site inside and outside the body, adding that they can be produced using natural ingredients on an industrial scale and have the capability of entrapping materials with different solubilities.
Compared to nanoemulsions and liposomes, the authors noted that solid lipid nanoparticles “have some distinct advantages,” including a higher encapsulation efficiency, the possibility of large-scale production and sterilization, the ability to provide high flexibility in controlling the release profile, and slower degradation rates – which allow for prolonged release profiles.
Fathi added that new nanostructure lipid carriers have an even smaller particle sizes compared to solid lipid nanoparticles, and have shown potential for the delivery of of lipophilic nutrients including vitamin E and omega 3 fatty acids.
Source: Trends in Food Science & Technology
Published online ahead of print, doi: 10.1016/j.tifs.2011.08.003
“Nanoencapsulation of food ingredients using lipid based delivery systems”
Authors: M. Fathi, M.R. Mozafari, M. Mohebbi