Abstract

The preservation of Vietnamese sea grapes (Caulerpa lentillifera) still faces major limitations due to their short shelf life and rapid deterioration of their sensory, aesthetic, and nutritional qualities. This results from commonly used NaCl brine rather than better alternative processing approaches.
This study aimed to optimize the parameters for preserving Vietnamese sea grapes. In particular, we optimized dehydration and color fixation techniques to enhance their sensory quality and shelf life. Optimal conditions were identified as blanching at 90°C for 10 s, rapid cooling at 10–15°C, and soaking in a color-fixation solution (15% NaCl + 5% sorbitol) for 10–15 min. The treated sea grapes demonstrated a superior color quality compared to common commercial products, with the green color index of 117.93 ± 44.86 and color intensity of 94.32 ± 45.36. Other improvements included a possible shelf life extension by 4–6 weeks, a decrease of 20–25% in spoilage rates, and a reduction of 10–15% in preservation and transportation costs. This can increase the net profit by 15–20%, as well as improve the product’s efficiency and competitiveness.
The developed method extends the shelf life of Vietnamese sea grapes, reduces their spoilage, and lowers preservation costs. This enables the product to meet international quality standards, enhancing its value and competitiveness. The remaining challenges include high initial investment, temperature control, staff training, and quality control systems. Future studies should identify changes in essential nutrients under long-term real-life transportation and storage conditions.

Keywords

Seaweed, Caulerpa lentillifera, color fixation, thermal blanching, dehydration

FUNDING

This research was funded by the Ministry of Agriculture and Environment as part of the project “Research and Development of Commercial Cultivation and Processing Technologies for Economically Valuable Seaweed Species in Vietnam” (No. 101/2022/HD-KHCN-TS).

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