Malaysian Journal of Analytical Sciences, Vol 26 No 5 (2022): 1082 - 1101

 

EVALUATION OF PHYSICOCHEMICAL PROFILE, MULTI ELEMENTAL COMPOSITION AND ANTIOXIDANT PROPERTY OF Heterotrigona itama FROM NORTHERN REGION IN MALAYSIA

 

(Penilaian Profil Fizikokimia, Komposisi Berbilang Unsur dan Sifat Antioksidan Heterotrigona itama Dari Wilayah Utara Di Malaysia)

 

Amira Syafiqah Jamaludin¹, Mardiana Saaid¹*, Ganapaty Manickavasagam¹, Ho Boon Han¹,

Norsyafiah Muhamad Faizal¹, Rozita Osman²

 

¹School of Chemical Sciences,

Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia

²Faculty of Applied Sciences,

Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia

 

*Corresponding author: mardiana@usm.my

 

 

Received: 25 March 2022; Accepted: 19 July 2022; Published:  30 October 2022

 

 

Abstract

Studies on physical and chemical compositions of stingless bee honey from northern region in Malaysia are still limited. Therefore, this study evaluates the physicochemical profile [pH, free acidity, ash content, total dissolved solids (TDS) and 5-hydroxymethylfurfural (5-HMF)], multi-elemental composition and antioxidant property of fresh stingless bee honey of Heterotrigona itama. Twenty honey samples were collected from the Northern regions (Kedah and Penang) of Malaysia. The results revealed that the values for pH, free acidity, ash content, and TDS were pH 3.01-3.43, 65.42-184.66 meq/kg, 0.07-0.61 g/100g, and 258.83-365.67 ppm, respectively. The concentration of 5-HMF in the honey samples elevated from not detected (fresh) to a maximum of 214.38 mg/kg (after 6- and 15-months storage). For multi-elemental composition, potassium was the highest concentration (16.13-1623.75 mg/kg) followed by calcium (36.23-272.5 mg/kg), sodium (31.25-148.25 mg/kg), aluminum (25.35-62.25 mg/L) and magnesium (11.14-179.75 mg/kg). Iron (< 0.02-41.55 mg/kg), copper (< 0.05-23.15 mg/kg), manganese (< 0.02-13.85 m/kg) and zinc (< 0.01-4.63 mg/kg) were found in low concentrations. Arsenic, lead, nickel, barium, cadmium and chromium were found in lower concentrations than the limit of detection, which indicates no contamination or environmental pollution on the studied areas. The total phenolic content (TPC) of the samples was 95.0-364.9 mg GAE/100g, showed relevant amounts of antioxidant properties, suggesting a source of natural antioxidants. In conclusion, the ash content, pH, and 5-HMF of fresh honey samples were compliant with the limit set by the Malaysian Standards. The 5-HMF concentration of all the honey samples after prolonged storage for six months exceeded the permitted range, which indicates that the honey samples deteriorated. Therefore, it is advised to consume the honey in less than six months.

 

Keywords: Stingless bee honey, Heterotrigona itama, northern Malaysia, physicochemical properties, multi-element

 

 

Abstrak

Kajian tentang komposisi fizikal dan kimia madu lebah tanpa sengat dari wilayah utara di Malaysia masih terhad. Oleh itu, kajian ini menilai profil fizikokimia (pH, keasidan bebas, kandungan abu, jumlah pepejal terlarut (TDS) dan 5-hidroksimetilfurfural (5-HMF)), komposisi pelbagai unsur dan sifat antioksidan madu lebah tanpa sengat segar iaitu Heterotrigona itama. Dua puluh sampel madu telah dikumpul dari wilayah Utara (Kedah dan Pulau Pinang) Malaysia. Keputusan menunjukkan bahawa nilai pH, keasidan bebas, kandungan abu, dan TDS masing-masing adalah pH 3.01-3.43, 65.42-184.66 meq/kg, 0.07-0.61 g/100g dan 258.83-365.67 ppm. Kepekatan 5-HMF dalam sampel madu adalah daripada tidak dikesan (segar) kepada maksimum 214.38 mg/kg (selepas penyimpanan 6 dan 15 bulan). Bagi komposisi berbilang unsur, kalium adalah berkepekatan tertinggi (16.13-1623.75 mg/kg) diikuti kalsium (36.23-272.5 mg/kg), natrium (31.25-148.25 mg/kg), aluminium (25.35-62.25 mg/L) dan magnesium (11.14-179.75 mg/kg). Besi (< 0.02-41.55 mg/kg), kuprum (< 0.05-23.15 mg/kg), mangan (< 0.02-13.85 m/ kg) dan zink (< 0.01-4.63 mg/kg) didapati dalam kepekatan rendah. Arsenik, plumbum, nikel, barium, kadmium dan kromium didapati mempunyai kepekatan lebih rendah daripada had pengesanan yang menunjukkan tiada pencemaran atau pencemaran alam sekitar di kawasan yang dikaji. TPC sampel ialah 95.0-364.9 mg GAE/100g, menunjukkan jumlah sifat antioksidan yang relevan, mencadangkan sumber antioksidan semulajadi. Kesimpulannya, kandungan abu, pH, dan 5-HMF sampel madu segar adalah mematuhi had yang ditetapkan oleh Piawaian Malaysia. Kepekatan 5-HMF bagi semua sampel madu selepas penyimpanan berpanjangan selama 6 bulan telah melebihi julat yang dibenarkan, menunjukkan sampel madu semakin merosot. Oleh itu, adalah dinasihatkan untuk mengambil madu kurang daripada 6 bulan.

 

Kata kunci: madu lebah tanpa sengat, Heterotrigona itama, utara Malaysia, sifat fizikokimia, pelbagai unsur

 

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