Ali is originally from Iran and moved to New Zealand to do a PhD in Food Science at Otago at the beginning of 2012.
In the course of his PhD to date he has generated publications, won the New Zealand Institute of Food Science and Technology (NZIFST) poster competition (Christchurch, New Zealand, 2014), the American Dairy Science Association (ADSA) graduate student oral presentation contest (Kansas City, USA, 2014), and was runner-up in the Riddet Institute three minutes thesis competition (Wellington, New Zealand, 2014).
Increasing consumer demand for healthy foods has stimulated the development of functional foods enhanced with beneficial bioactives such as polyphenols originating from natural sources. Green tea (GT) antioxidants have been well recognised for their wide range of health benefits including anticancer effect, anti-cardiovascular disease potential, and HIV protection. Green tea antioxidants have also been used for maintaining the ordinary flavour and extending the oxidative process in food ingredients and eventually increasing their stability and shelf life.
The in vitro antioxidant activity of tea polyphenols has been patented for their ability to scavenge reactive oxygen and nitrogen species, chelate redox-active transition metal ions, inhibit redox-sensitive transcription factors, and prevent “pro-oxidant” enzymes.
Recently, increasing interests have been attracted to the application of the tea polyphenols in foods such as dairy products and accordingly developing new technologies to extract and process these polyphenols.
Cheese could be a good delivery vehicle for GT antioxidants because of its intrinsic nutritional values and long shelf life. However, there exist technical challenges for such an application. The addition of tea antioxidants might cause decreased cheese quality as these bioactives could impart negative effects on cheese colour, pH and texture via chemical and physical interactions between tea phenolic compounds and milk. Such interactions with caseins has been patented and considered as one major reason responsible for loss of added phenolics. To eliminate such a loss, we have introduced a simple, fast and inexpensive liposomal encapsulation method to encapsulate GT antioxidants in order to prevent their interaction with milk proteins prior to digestion. Encapsulation of bioactive compounds has the potential to improve bioactivity, bioaccessibility, bioavailability and stability. In addition, it is considered as an industry-relevant approach to minimise the astringency of incorporated bioactive compounds in functional foods.
In the current project, we are trying to further investigate the chemical composition, pH, and antioxidant properties of both low-fat and full-fat cheeses that have been fortified with such liposome-encapsulated green tea polyphenols over a 90-day ripening period, and study the effect of the liposomal encapsulation on the recovery of GT catechins from the digesta after fortified cheese subjected to a simulated gastrointestinal digestion.
We are also investigating the potential chemical interactions between milk fat globules (MFG) and catechins. To the best of our knowledge, this is the first study in this field and of great importance as it provides useful information about the role of MFGs in dairy systems containing bioactive compounds such as catechins.
Ali Rashidinejad, David W. Everett, John Birch, and Dongxiao Sun-Waterhouse (2012). The effects of fruit extracts on the antioxidant activity and phenolic contents of whey proteins. Annual colloquium of the Riddet Institute, Palmerston North, New Zealand.
Ali Rashidinejad, E. John Birch, Dongxiao Sun-Waterhouse3 & David W. Everett (2013). Effects of catechin on the phenolic content and antioxidant properties of low-fat cheese. International Journal of Food Science and Technology. 48 (12): 2448-2455
Ali Rashidinejad, E. John Birch, Dongxiao Sun-Waterhouse3 & David W. Everett (2013). The effect of fruit extracts on the antioxidant activity and phenolic contents of whey proteins. The New Zealand institute of food science and technology (NZIFST) conference, Hastings, New Zealand
Ali Rashidinejad, E. John Birch, Dongxiao Sun-Waterhouse3 & David W. Everett (2014). Delivery of green tea catechin and epigallocatechin gallate in liposomes incorporated into low-fat hard cheese. Food Chemistry Journal. 156 (1): 176–183
Ali Rashidinejad, E. John Birch, Dongxiao Sun-Waterhouse3 & David W. Everett (2014). The feasibility of manufacturing a functional cheese enriched with liposomal encapsulated green tea catechins. New Zealand Institute of Food Science and Technology (NZIFST) conference, Christchurch, New Zealand.
Ali Rashidinejad, E. John Birch, Dongxiao Sun-Waterhouse3 & David W. Everett (2014). The in vitro recovery of liposomal encapsulated green tea catechins incorporated into low-fat cheese. New Zealand Institute of Food Science and Technology (NZIFST) conference, Christchurch, New Zealand.
Ali Rashidinejad, E. John Birch, Dongxiao Sun-Waterhouse3 & David W. Everett (2014). Antioxidant activity after in vitro gastrointestinal digestion of cheese containing catechins encapsulated within liposomes. American Dairy Science Association (ADSA) conference, Kansas City, USA.