Antioxidant potential and physicochemical characterization of yellow, purple and orange passion fruit.

This study evaluated yellow, purple and orange passion fruit in pulp, peel, and seed for physicochemical characteristics, proximate composition, minerals, antioxidant capacity (DPPH and ABTS), phenolic compounds, carotenoids, flavonoids and anthocyanins. Yellow passion fruit presented higher concentrations of pectin (37.37 g/100 g) in peels; high cryptoxanthin, α-carotene, β-carotene, provitamin A, quercetin, and kaempferol in pulps and higher values of ash and total dietary fiber in seeds.

Stability of functional compounds and antioxidant activity of fresh and pasteurized orange passion fruit (Passiflora caerulea) during cold storage.

This research aimed to evaluate differences in the stability of physicochemical and color parameters, phenolic compounds, flavonoids, carotenoids and antioxidant capacity in fresh and pasteurized juice of orange passion fruit, respectively cold stored (8 °C) during 0-4 or during 0-15 days. The results showed that in the physicochemical analysis, no significant differences were observed comparing pasteurized and fresh juice during storage. The pasteurized juice showed higher concentrations of color parameters, phenolic compounds (15% more of retention for days 0 and 4), epigallocatechin gallate (40% in day 0 and 27% in day 4), lycopene (142% for day 0 and 39% for day 4), total carotenoids (114% in day 0 and 8% in day 4) and antioxidant capacity (12% in day 0 and 7% in day 4).

Characterization of must and wine of six varieties of grapes by direct infusion electrospray ionization mass spectrometry.

Samples of must derived from six different varieties of grapes taken during the fermentation process, as well as the respective wine samples directly after the end of the malolactic fermentation, were analyzed by direct infusion negative ion mode electrospray ionization mass spectrometry (ESI-MS). Diagnostic ions for must were different from those of wine samples, although small variations for each of the grape varieties were also detected. The addition of unfermented must or sugar to wine could also be clearly detected.

Aflatoxin screening by MALDI-TOF mass spectrometry.

Efficient detection of aflatoxins B1, B2, G1, and G2 has been performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using a UV-absorbing ionic liquid matrix to obtain "matrix-free" mass spectra and addition of NaCl to enhance sensitivity via Na+ cationization. Using ionic alpha-cyano-4-hydroxycinnamic acid (Et3N-alpha-CHCA) as the matrix, matrix-free mass spectra in the m/z range of interest are acquired, and the B1, B2, G1, and G2 aflatoxins are readily detected with an LOD as low as 50 fmol. The technique is fast, requires little sample preparation and no derivatization or chromatographic separation, and seems therefore to be suitable for high-throughput aflatoxin screening.