Document Type: Note

Authors

Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Universitas Ahmad Dahlan, Yogyakarta, Indonesia

Abstract

Guava fruit (Psidium guajava L.) has many varieties, one of them is crystal guava. Crystal guava contains vitamin C that can be oxidated easily by temperature. Therefore, this research aimed to determine the levels of vitamin C in the crystal guava juice with some storage places. The crystal guava sample was obtained from Bogor and it was kept in different places and temperatures. The fruits were placed in the freezer, refrigerator, and room temperature with storage for 3 days, and all samples were made a juice. Based on the visual evaluation, any different color from guava fruit. Moreover, the quantification method of vitamin C level in guava juice by HPLC can be performed with a flow rate of 1 ml/min using the mobile phase ratio (methanol/water: 5/95, v/v), λmax: 265 nm and C18 as a stationary phase. Qualitative analysis showed that the sample contained a vitamin C level that produced the same retention time on the HPLC tests. The storage effect of the vitamin C content in guava juice from a fresh sample, and the stored guava in the freezer, in the refrigerator, and in-room temperature were 3.28 mg/ml, 3.20 mg/ml, 1.65 mg/ml, and 0.82 mg/ml, respectively. Therefore, it can be concluded that the best storage for guava fruit is a freezer because the vitamin C levels in crystal guava didn’t have significant differences after treatment.

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