Quality Assessment of Burdekin Plum (Pleiogynium timoriense) during Ambient Storage

Abstract

Pleiogynium timoriense, commonly known as Burdekin plum (BP), is among many Australian native plants traditionally used by Indigenous people. However, only limited information is available on the nutritional and sensory quality of BP grown in Australia as well as its changes during storage. Therefore, this study evaluated the quality of BP during one week of ambient storage (temperature 21 °C, humidity 69%). Proximate analysis revealed a relatively high dietary fiber content in BP (7–10 g/100 g FW). A significant reduction in fruit weight and firmness (15–30% and 60–90%, respectively) with distinguishable changes in flesh color (ΔE > 3) and an increase in total soluble solids (from 11 to 21 °Brix) could be observed during storage. The vitamin C and folate contents in BP ranged from 29 to 59 mg/100g FW and 0.3 to 5.9 μg/100g FW, respectively, after harvesting. A total phenolic content of up to 20 mg GAE/g FW and ferric reducing antioxidant power of up to 400 μmol Fe2+/g FW in BP indicate a strong antioxidant capacity. In total, 34 individual phenolic compounds were tentatively identified in BP including cyanidin 3-galactoside, ellagic acid and gallotannins as the main phenolics. Principle component analysis (PCA) of the quantified phenolics indicated that tree to tree variation had a bigger impact on the phenolic composition of BP than ambient storage. Sensory evaluation also revealed the diversity in aroma, appearance, texture, flavor and aftertaste of BP. The results of this study provide crucial information for consumers, growers and food processors.

Physicochemical, antioxidant and microbial stability of Burdekin plum leathers

“…(2006). Details were reported in our previous work (Chen et al ., 2023). TPC results were expressed as mg gallic acid equivalents (GAE) per g dry weight (DW).…”

“…The main phenolic compounds in the fruit puree and leather were determined as reported by Chen et al (2023) with slight modifications. A Thermo Vanquish TM UHPLC system (Thermo Fisher Scientific, Waltham, MA, USA) equipped with a Thermo Orbitrap Exploris TM 120 mass spectrometer and a Waters BEH C18 analytical column (150 9 2.1 mm, 1.8 lm particle size; Waters, Rydalmere, NSW, Australia) at 50°C were used to perform the analyses (Hong et al, 2021).…”

“…Anthocyanins have been identified as the major water-soluble pigments contributing to the reddish colour of Burdekin plums. Because the major anthocyanin in Burdekin plums is cyanidin 3-galactoside with the content of cyanidin 3-glucoside being a hundredth less than that of cyanidin 3-galactoside and the close retention times International Journal of Food Science and Technology 2024 of these 2 compounds (Chen et al, 2023), cyanidin 3galactoside and 3-glucoside were quantified together. The total content of cyanidin 3-galactoside and cyanidin 3-glucoside (400-1600 mg kg À1 ) reduced to less than one-third of the original content (100-500 mg kg À1 ) after making into leather and contained less than 5% (9-70 mg kg À1 ) after storing for 6 months.…”

“…In Australia, the plum-like fruits are commonly known as Burdekin plums (BP) (Low, 1991). BP is a source of fibre, minerals and polyphenols including anthocyanins and ellagitannins (Cherikoff, 2015;Chen et al, 2023), and is also one of the many underutilised Australian native fruits (Nand, 2008). BP have also been found to show a strong antioxidant capacity (Netzel et al, 2007) and other in vitro bioactivities such as anticancer (Said et al, 2018), anti-inflammatory and hepatoprotective effects (Said et al, 2015).…”