Mechanical and thermal treatments of tomato and carrot: Effects on in vitro bioaccessibility of carotenes and microstructure

TY - CONF

T1 - Mechanical and thermal treatments of tomato and carrot

T2 - 5th International Technical Symposium on Food Processing, Monitoring Technology in Bioprocesses and Food Quality Management

AU - Svelander, Cecilia A.

AU - Tibäck, Evelina A.

AU - Lopez-Sanchez, Patricia

AU - Gammelgård, Anna

AU - Ahrné, Lilia M.

AU - Langton, Maud I.B.C.

AU - Alminger, Marie A.G.

PY - 2009

Y1 - 2009

N2 - Human studies have demonstrated that bioavailability of carotenes can be greatly increased by processing, but the difference between processing methods is not yet widely investigated. The objective of the current study was to assess the impact of thermal and mechanical processing of tomato and carrot on carotenoid bioaccessibility in vitro. It was demonstrated that a combination of extensive homogenization and heat treatment was required for an increased bioaccessibility. Both low and high temperature blanching of tomato significantly increased lycopene in vitro bioaccessibility of crushed tomato, from 5.1±0.2 to 9.2±1.8 and 9.7±0.6 mg kg-1 respectively. Heating of carrot pieces at 90°C for 60 min followed by homogenization resulted in a 1.6-fold increase in the relative -carotene bioaccessibility compared with raw, homogenized, carrot. However, heating of homogenized carrot at 90°C for up to 120 min did not significantly increase in vitro bioaccessibility of -carotene. Finally, addition of 5% olive oil during homogenization of carrot resulted in a 10-fold higher in vitro bioaccessibility of -carotene in the micellar fraction. The results show that a combination of thermal and mechanical treatments of tomato and carrot can have a substantial impact on carotene in vitro bioaccessibility. Also, carotenoid bioaccessibility may be markedly enhanced by addition of oil.

AB - Human studies have demonstrated that bioavailability of carotenes can be greatly increased by processing, but the difference between processing methods is not yet widely investigated. The objective of the current study was to assess the impact of thermal and mechanical processing of tomato and carrot on carotenoid bioaccessibility in vitro. It was demonstrated that a combination of extensive homogenization and heat treatment was required for an increased bioaccessibility. Both low and high temperature blanching of tomato significantly increased lycopene in vitro bioaccessibility of crushed tomato, from 5.1±0.2 to 9.2±1.8 and 9.7±0.6 mg kg-1 respectively. Heating of carrot pieces at 90°C for 60 min followed by homogenization resulted in a 1.6-fold increase in the relative -carotene bioaccessibility compared with raw, homogenized, carrot. However, heating of homogenized carrot at 90°C for up to 120 min did not significantly increase in vitro bioaccessibility of -carotene. Finally, addition of 5% olive oil during homogenization of carrot resulted in a 10-fold higher in vitro bioaccessibility of -carotene in the micellar fraction. The results show that a combination of thermal and mechanical treatments of tomato and carrot can have a substantial impact on carotene in vitro bioaccessibility. Also, carotenoid bioaccessibility may be markedly enhanced by addition of oil.

KW - Carrot

KW - Dietary fat

KW - In vitro bioaccessibility

KW - Light microscopy

KW - Lycopene, -carotene

KW - Microstructure

KW - Thermal and mechanical processing

KW - Tomato

M3 - Paper

AN - SCOPUS:74549196478

SP - 273

EP - 280

Y2 - 31 August 2009 through 2 September 2009

ER -