M Sc

The research work entitled “Physicochemical characteristics of Indian bee honey and stingless bee honey in Kerala with special emphasis on moisture” was carried out at the Department of Agricultural Entomology and Department of Soil Science & Agricultural chemistry, College of Agriculture, Vellayani, Kerala Agricultural University during 2019-2021. The objectives of the study were, to understand the quality aspects of honey produced by Indian bee and stingless bee in Kerala and to determine the effect of processing temperature on moisture content of honey.
Objectives of the research work include, collection of comb honey from Indian bee and pot honey from stingless bee species from different locations in 14 districts of Kerala; Physicochemical observations from collected honey samples in-order to determine moisture percentage, Electrical Conductivity(EC), pH, Ash content and Hydroxy methyl furfural (HMF). Various physicochemical characters were studied with help of Palm Abbe Digital Refractometer, Hand held Refractometer, EC meter, pH meter, Muffle Furnace and UV Spectrophotometer.
Moisture percentage of Indian bee honey samples varied from 20.90 to 27.80 percentage. Average moisture content of Indian bee honey samples were 23.10%. Moisture percentage of stingless bee honey samples varied from 21.30 to 25.80%. Average moisture percentage of stingless bee honey samples were 23.40%. Honey from 20 locations of both Indian bee and stingless bee falls under the moisture range 22.10 to 25.0%.
Electrical conductivity (EC) of Indian bee honey samples varied from 0.44 to 0.90 mS/cm. The average EC of Indian bee honey samples were 0.58 mS/cm. Electrical conductivity (EC) of stingless bee honey samples varied from 0.54 to 1.14 mS/cm. Average EC of stingless bee honey samples were 0.77 mS/cm. Among 28 samples of Indian bee honey, EC from 0.51 to 0.60 mS/cm was observed in 15 whereas among 28 samples of stingless bee honey EC of 0.71 to 0.80 mS/cm was observed in 12 samples.
pH of Indian bee honey samples varied from 3.24 – 4.11. Average pH of Indian bee honey samples were 3.73. pH of stingless bee honey samples varied from 3.35 –
3.92. Average pH of Stingless bee honey samples were 3.61. Among 28 samples of Indian bee honey, 10 samples recorded pH from 3.51 to 3.70 and among 28 samples of stingless bee honey, 12 samples recorded pH from 3.51 to 3.70.
Ash content of Indian bee honey samples varied from 0.18 to 0.43g/100g. Average ash content of Indian bee honey samples were 0.25g/100g. Ash content of stingless bee honey samples varied from 0.22 – 0.57g/100g. Average ash content of stingless bee honey samples were 0.36g/100g. Among 28 samples of Indian bee honey, 21 samples show 0.21 to 0.30g/100g. Among 28 samples of Stingless bee honey, 17 samples show 0.31 to 0.40g/100g.
HMF content of Indian bee honey samples varied from 11.66 to 47.64mg/kg. Average HMF content of Indian bee honey samples were 31.87 mg/kg. HMF content of stingless bee honey samples varied from 17.06 to 98.23 mg/ kg. Average HMF content of stingless bee honey samples were 55.22 mg/kg. Among 28 samples of Indian bee honey, 18 samples show 21.00 to 40.99mg/kg. Among 28 samples of stingless bee honey, 22 samples show 31.00 to 70.99mg/kg. It was observed that, three stingless bee honey samples had recorded HMF greater than the permissible limit of 80mg/kg (i.e. 93.36, 94.44 and 98.23).
Processing of Indian bee honey at 70°C for 35 minutes shows a better reduction of moisture percentage level from 23.0 to 21.3%. Processing of Stingless bee honey at 70°C for 35 minutes shows a better reduction of moisture percentage from 25.2 to 21.5%. The observations were recorded with a palm Abbe Digital Refractometer.
To conclude, as per the existing FSSAI standards, the moisture content of honey should be below 20 per cent. However, honey produced by farmers in Kerala (Indian bee or the stingless bees) is found to have moisture content above 21 per cent. Hence, there appears to be a need for setting separate quality standards for both processed and raw honey of the Indian bee and Stingless bee species.

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