CHIANG MAI UNIVERSITY JOURNAL OF NATURAL SCIENCES

Volume 18, No. 04, Month OCTOBER, Year 2019, Pages 444 - 460

Application of citric acid, sodium chloride and peroxyacetic acid as alternative chemical treatment for organic trimmed aromatic coconut

Diem Thi Ngoc Nguyen, Kullanart Tongkhao, and Sasitorn Tongchitpakdee

Abstract Download PDF

Shelf-life of trimmed coconut is usually extended using sulfite agents or chlorine. However, in organic produce, applications of sulfite agents is prohibited while chlorine is restricted. The objective of this study was aimed to extend the shelf-life of organic trimmed aromatic coconut using citric acid (CA), sodium chloride (NaCl) and peroxyacetic acid (PAA). Organic trimmed aromatic coconuts were dipped in CA (10% and 20%) in combination with NaCl (10% and 15%) followed by dipping in PAA (80 ppm). All samples were compared with control (no dipping) and those dipped in 3% sodium metabisulfite (SMS). During 8 weeks of storage at 2 °C, qualities of treated coconuts including visual quality, color values (L*, a*, b*) and total plate count (TPC) on surface of samples were evaluated. Chemical qualities (titratable acidity (TA), pH and total soluble solids) of coconut water were also determined. The results showed that beside SMS, treatment 20% CA + 15% NaCl was the most effective treatment for maintaining visual quality and color as well as controlling microbial growth (P < 0.05). Moreover, PAA treatment could only help reducing the TPC up to five weeks of storage and resulted in yellowish color. Therefore, 20% CA + 15% NaCl could be an alternative chemical treatment in controlling postharvest deterioration of organic trimmed aromatic coconut.

Keywords

Organic trimmed aromatic coconut, Citric acid, Peroxyacetic acid, Shelf–life, Sodium chloride

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