Characteristics of fat,and saponin and tannin contents of 11 varieties of rambutan (Nephelium lappaceum L.) seed

Rambutan seed is discarded during fruit processing. However, the seed contains a considerable amount of crude fat. Hence, the objective of this study was to determine two anti-nutritional constituents, namely saponin and tannin, and to characterize the fat of the seeds of 11 varieties of rambutan fruit. Results showed that the range of crude fat content is fairly narrow (36.13–39.13 g/100 g dried seeds). The iodine value and free fatty acid content of the fat were 38.50–50.61 g I₂/100 g fat and 0.99–2.18% as oleic acid, respectively. Oleic (33.35–46.64%) and arachidic (26.03–33.27%) acids were the main fatty acids in the fat. HPLC analysis showed that the fat comprised mainly five unknown triacylglycerols (83.94–95.33%). The melting and crystallization curves showed that the fat exhibited four to nine non-distinct peaks. The complete melting and crystallization onset temperatures of the fat were 24.8–50.6°C and 24.1–39.4°C, respectively, while the melting and crystallization enthalpies of the fat ranged from 71.2 to 141.7 J/g and from 60.4 to 88.9 J/g, respectively. At 0°C, the solid fat index of the fat ranged between 87.4% and 91.6% and the fats of some varieties melted completely at human body temperature. The saponin and tannin contents of the seed were 14.27–18.96 mg soya saponin/100 g and 4.40–26.68 mg catechin equivalent/100 g, respectively. Findings showed that rambutan seed fat has potential to be used in various sectors of food industry.     

UVC dosage effects on the physico-chemical properties of lime (Citrus aurantifolia) juice

A phenyl lipid alkaloid and seven phenolic compounds were isolated from the aerial part of Spergularia marina, a halophyte that grows on salt marshes and tidal flat. These compounds were identified as 2,4-di-tert-butylphenol, N-hexacosanoylanthranilic acid, tryptophan, 4-hydroxybenzyol glucopyranoside, luteolin 6-C-β-D-glucopyranoside 8-C-β-D-(2-O-feruloyl)glucopyranoside, luteolin 6-C-β-D-(2-O-feruloyl)glucopyranoside 8-C-β-D-glucopyranoside, apigenin 6-C-β-D-glucopyranoside 8-C-β-D-(2-O-feruloyl)glucopyranoside, and apigenin 6-C-β-D-(2-O-feruloyl)glucopyranoside 8-C-β-D-glucopyranoside. The structures were determined by nuclear magnetic resonance and electrospray ionization-mass spectroscopy.     

A Review of Clean-Label Approaches to Chilli Paste Processing

Consumer demand for clean-label food products is increasing. Moreover, the production of ready-to-cook products have begun to include clean-label efforts. Dried chilli, the raw material for chilli paste, is susceptible to contaminants such as mould dirt and pesticides that must be removed to maintain the safety and quality of products. In this review, trends related to processes involved in chilli paste production are highlighted. Improvements in preservation technology and the potential for using a clean-label approach to produce premium-quality chilli pastes were explored. Ultrasound washing and high-pressure processing could be combined as part of a hurdle technique for processing chilli pastes that align with consumer values. Ultrasound washing disinfects and removes dirt pesticides and chemical residues present on dried chillies. High-pressure treatments inactivate microorganisms and enzymes, which could extend the shelf-life of chilli pastes. Additionally, organic acid and garlic can be used as natural preservatives to improve the formulation without using artificial ingredients. This clean-label concept can be integrated into the hurdle strategy to produce chilli paste that fulfils the consumer demand for a safe, naturally nutritional product with an extended shelf-life.     

Rheological properties of ultraviolet-irradiated and thermally pasteurized Yankee pineapple juice

The rheological behaviour of Yankee pineapple juice was examined for the effect of ultraviolet (UV) irradiation (53.42 mJ/cm²) and compared with untreated juice and a thermally pasteurized (80 °C for 10 min) juice. A rheological test was performed on all types of juice in the temperature range 5 °C to 25 °C using a concentric cylinder rheometer at a shear rate range of 10–290 s⁻¹. The comparative analysis found that the best flow curves were described by the Bingham model with an initial shear stress. The entangled pulps in the juices prevented free flow at zero shear rate. There was no significant variation between the plastic viscosities of the untreated and UV-irradiated juice at all temperatures. The activation energy (E_a) of the untreated, UV-irradiated and thermally pasteurized juice was 6.80, 8.19 and 8.50 kJ/mol respectively.