Cactus pear fruit: A new source for a natural sweetener

The use of cactus pear (Opuntia ficus indica L.) to obtain a new natural liquid sweetener was studied. The juice of the fruit (16.5 degrees Brix) was clarified with enzymes, treated with active carbon to take out the color and vacuum concentrated to obtain a 60 degrees Brix syrup or liquid sweetener. Physical and chemical characteristics determined included: aw; reducing sugars (as inverted sugar); glucose (%); ash content (%); sugar composition by TLC; OD (420 nm) and Y, x, y chromaticity coordinates; viscosity (cps) and density (g/ml). Sensory analyses to determine the relative sweetness were also conducted. Cactus pear syrup contained 52.38% reducing sugar. The syrup had a pH of 4.31, a viscosity of 27.05 cps, an A, of 0.83, a density of 1.2900 g/ml, an acidity (as citric acid) of 0.74% and an ash content of 1.4%. Compared with traditional sweeteners such as fructose and glucose syrup, the acidity was greater than that of HFCS (high fructose corn syrup) of 0.035%, and the ash values were considered a little high compared to glucose syrup which is 1.0%; these disparities can be attributed to the different processing conditions employed. Sensory evaluation revealed the same relative sweetness for cactus pear syrup and glucose, but lower than fructose; cactus pear syrup had a relative sweetness value of 67 with respect to sucrose (100).