Utilisation Potential of Feijoa Fruit Wastes as Ingredients for Functional Foods

作者：Sun Waterhouse Dongxiao^*; Wang Wei; Waterhouse Geoffrey I N; Wadhwa Sandhya S

来源：Food and Bioprocess Technology, 2013, 6(12): 3441-3455.

DOI：10.1007/s11947-012-0978-3

• Acidified water extract
• Feijoa wastes
• Fibre polysaccharides
• Aqueous ethanolic extract
• Polyphenols
• Water extract

Feijoa fruits have high antioxidant activity as they contain significant concentrations of polyphenols (PPs), carotenoids and vitamins. This study evaluates the colour, pH, total soluble solids (TSS), pectin fibre content, total extractable PP content (TEPC) and total antioxidant activity of the extracts generated from the fruit wastes (primarily skin and some flesh) remaining after feijoa flesh consumption. Extractions were conducted at room temperature and 50 A degrees C using accelerated solvent extraction technology and different extraction media [water, acidified water (containing citric acid, pH 3.5), and 30, 50 and 80 % (v/v) aqueous ethanol solutions]. Results show that the composition and properties of the extracts depend on the extraction media and, to a lesser extent, on the extraction temperature. The 80 % ethanolic extract was bright green in colour. The water and acidified water extracts showed more browning than the ethanolic extracts, suggesting possible detrimental sensory impacts for food applications. The TSS decreased in the order of 80, 50 and 30 % ethanolic and water extracts. The 50 % ethanolic extract had the highest TEPC and antioxidant activity at both extraction temperatures, which was supported by high performance liquid chromatography analyses. The extracts produced with solutions containing less ethanol, especially water extracts, had higher pectin contents. The UA content of the extract produced using water alone was the highest (5.56 % as GalA) at 20 A degrees C, whilst that produced using 30 % ethanol solution was the highest (3.90 % as GalA) at 50 A degrees C. Higher extraction temperature (50 A degrees C) resulted in lower pectin contents. These results demonstrate the potential of feijoa waste extracts, especially 50 and 80 % ethanolic extracts, as ingredients for functional food applications.

• 出版日期2013-12