Abstract:
Application of weak acid and preservatives on tomatoes has the potential to reduce
the loss of functional properties during drying. The effects of using sodium
metabisulphite (SMB) and citric acid (CA) to control the degradation of nutraceuticals
in dried tomatoes were studied. The following treatments: T0 (control, no additives),
T1 (1% w/v CA), T2 (0.5% w/v CA +0.5% w/v SMB), and drying methods
(dehydration, sun, and solar) were used. The T2 pretreated samples, dried using the
sun, solar, and dehydration had total soluble solids (TSS) (5.10%), total sugar (TS)
(7.32 g/100 g), and rehydration ratio (RR) (2.0) and β-carotene
(30.0 mg/100 g), lycopene
(51.3 mg/100 g), ascorbic acid (14.1 mg/100 g), respectively. The T2 pretreated
and dehydrated samples had a high Trolox equivalent antioxidant capacity (TEAC)
and 2,2-diphenyl-
1-
picrylhydrazyl
radical scavenging activity. By using T2 treatment
and dehydration, the tomato had the best functional properties, which would be used
as optimal conditions for preserving tomatoes.
Novelty impact statement: Hybrid Amukela Plus tomatoes pretreated with 0.5% w/v
CA +0.5% w/v SMB and dried -in
a food dehydrator preserved -further
degradation
of nutraceutical compounds and resulted in a β-carotene
(30.0 mg/100 g), lycopene
(51.3 mg/100 g), and ascorbic acid (14.1 mg/100 g) content during storage. These
treatments produced dried tomatoes with over 50% Trolox equivalent antioxidant
capacity (TEAC) and 2,2-diphenyl-
1-
picrylhydrazyl
(DPPH) radical scavenging activity.
Solar and sun-drying
treatments have significant damage on the nutraceutical
compounds in the dried hybrid tomatoes.
