Chlorophylls and carotenoids of kiwifruit puree are affected similarly or less by microwave than by conventional heat processing and storage

Modulation of chemical stability and in vitro bioaccessibility of beta-carotene loaded in kappa-carrageenan oil-in-gel emulsions

In the present paper, ionotropically structured κ-carrageenan based oil-in-gel (o/g) emulsions were tested as potential carrier systems for the delivery of β-carotene. In situ ionic gelation was induced by Na⁺, K⁺ or Ca²⁺ added at the level of 0.2-0.6% (w/w). All o/g emulsions exerted a true gel like behaviour with storage modulus (G') being reduced according to the order: K⁺>Ca²⁺>Na⁺. Ionic gelation induced a moderate increase in the microscopically assessed lipid droplets radii. O/g emulsions containing monovalent ions exerted the highest β-carotene retention throughout isothermal storage particularly at high (37 and 55°C) temperatures. Notwithstanding, increasing ionic strength resulted in acceleration of β-carotene degradation rates for all cation species. β-Carotene bioaccessibility was significantly lower in Ca²⁺o/g emulsions due to the formation of complexes between the biopolymer matrix containing β-carotene and bile salts. A good correlation between β-carotene bioaccessibility, physical and colloidal aspects of the micellar digesta fractions was observed.

Characterization of physiochemical and microbiological properties, and bioactive compounds, of flour made from the skin and bagasse of kiwi fruit (Actinidia deliciosa)

The objective of this study was to analyze the physicochemical and microbiological properties, as well as the bioactive compounds, of flour made from the skin and bagasse of two varieties (Bruno and Monty) of kiwi fruit (Actinidia deliciosa) at two stages of maturation. The flour made with kiwi fruit peel from both varieties showed higher levels of bioactive compounds and antioxidant activity that the flour made with bagasse from both varieties. The flour made with green kiwi fruit skin from the Bruno variety had higher DPPH values and levels of phenolic compounds (1262.34 mg GAE/100g flour), while the Monty variety showed higher FRAP values, vitamin C (189.06 mg/100g flour), flavonoids (486.47 mg/100g flour), chlorophylls (12.13 mg/100g flour) and carotenoids (246.91 μg/100g flour). Flour made from kiwi fruit bagasse can be used to reduce agro-industrial waste. This flour is a promising ingredient which can be used to enrich products providing dietary fiber and bioactive compounds, as well as antioxidant action.