Market analyst Mintel predicted last year that interest in fruits sourced from the Amazon would continue to grow due to consumer trends towards natural products and exotic ingredients. Exotic fruits such as acai and cupuacu are gaining notoriety for both their anti-aging benefits and through a link to the "super-foods" concept. "The search for world unique food ingredients and flavours with enhanced health-beneficial properties is at present one of the key market trends. Botanicals from the regions linked to wellness and natural functionality with exotic fruits called "superfruits", such as acai from Amazonia, are becoming a popular target of health-conscious consumers and industry managers," wrote lead author Michael Netzela a post-doctoral fellow sponsored by the Humboldt Foundation in Germany, hosted by the Food Science Australia and supervised by Izabela Konczak.
"We propose [for the first time twelve native Australian fruits] to be considered as a potential source of bioactive phytochemicals for application in health promoting foods," he added in the journal Innovative Food Science & Emerging Technologies. Netzela and collaborators from The Ohio State University compared the phenolic content and the radical scavenging activities of 12 native Australian fruits with blueberries.
Antioxidant and radical scavenging activities were measured using the Trolox Equivalent Antioxidant Capacity (TEAC) assay and the Photochemiluminescence (PCL) assay, while the total phenolic content was determined using the Folin-Ciocalteu assay. Netzela and co-workers report that the selected fruits are rich sources of antioxidants, with stronger radical scavenging activities than blueberries. Indeed, compared to blueberries TEAC value of 39.45 trolox equivalents per gram, Kakadu plum and Burdekin plum had TEAC values of 204.8 and 192.0 trolox equivalents per gram, respectively.
"Therefore, utilizing native Australian fruits as sources of bioactive phytochemicals could offer enormous opportunities for the functional food industry. Studies for the identification of further antioxidant compounds as well as clinical trials for testing the fruits bioactivity in vivo are in progress," they wrote. More research is also needed to examine the potential of the fruit to offer novel sources of colours and flavours for the food industry.
The researchers examined the potential of riberries (Syzygium luehmannii, Myrtaceae), brush cherry (Syzygium australe, Myrtaceae), muntries (Kunzea pomifera F. Muell., Myrtaceae), Illawarra plum (Podocarpus elatus R. Br. ex Endl., Podocarpaceae), Burdekin plum (Pleiogynium timorense DC. Leenh, Anacardiaceae), Cedar Bay cherry (Eugenia carissoides F. Muell., Myrtaceae), Davidson's plum (Davidsonia pruriens F. Muell. var. pruriens, Davidsoniaceae), Molucca raspberry (Rubus moluccanus var. austropacificus van Royen, Rosaceae), finger lime (yellow and red, Microcitrus australasica, Rutaceae), Kakadu plum (Terminalia ferdinandiana, Combretaceae) and Tasmanian Pepper (Tasmanian lanceolata R. Br., Winteraceae). The project was fully funded by Food Science Australia.
Source: Innovative Food Science & Emerging Technologies (Elsevier) Published on-line ahead of print: doi: 10.1016/j.ifset.2007.03.007 "Native Australian fruits - a novel source of antioxidants for food"
Authors: M. Netzela, G. Netzela, Q. Tianb, S. Schwartzc and I. Konczak