2.2.2. Preparation
All the ingredients required for cake preparation were weighed
accurately. Creaming of the shortening was done with a Hobart
mixer at medium speed (418 rpm) for 5 min. Sugar was added
during creaming, in case of neotame sweetened cake, bulking
agents (polydextrose and maltodextrin) were added. The cake gel
was added and blended for 2 min to improve the quality of the
batter and final product. WPC was added and mixed at low speed
(218 rpm) for 3 min.
The wheat flour, corn flour and baking powder which were previously sieved together using 12 103 mm sieve size were added and blended continuously at medium speed for 3 min.
In case of neotame sweetened cake, as the quantity of neotame was low as compared to other ingredients, hence for proper mixing, itwas first mixed properly withwater then added to the mix. Finally, water was added and blended at low speed (218 rpm) for 2 min. The batter was filled into pre greased cake molds and was baked at 180 C for 20 min in a convection oven.
2.2.2.1. Preparation of ice cream. Ice creamwas manufactured with either sucrose or with neotame by using the method of De (2011) with some modifications i.e. in case of neotame sweetened ice cream, sugar was completely replaced with the most acceptable level of neotame (30 mg/kg ice cream mix basis); 9.9% maltodextrin and 1.5% WPC were used as bulking agent and 0.38% stabilizer and emulsifier were used.
2.3. Sample preparation Twenty gramof cake samplewas accuratelyweighed in a 100 ml beaker. Fifty milliliter of aqueous methanol solution (methanol/ H2O, 20:100, ml:ml) was added to it and vortexed for 2 min. It was placed in an ultrasonic bath maintained at 40 C for 20 min. The solution was then cooled to room temperature (30 C) and centrifuged at 2000 g for 10 min.
The supernatant was transferred to a 50 ml volumetric flask and added 2 ml of Carrez solution no. 1 followed by 2 ml of Carrez solution no. 2. The solution was shaken vigorously and allowed to stand at room temperature for 10 min. After dilution up to 50 ml with HPLC water, filtration was carried out using Whatman no.1 filter paper.
The filtrate was introduced into the SPE cartridge for pre-purification.In case of ice cream, trapped air bubbles were removed from ice cream by sonication at 30 C for 20 min. Ten gram of ice cream mix was accurately weighed in a 100 ml beaker and 25 ml of aqueous methanol solutionwas added. The amount of Carrez solutions no. 1 and 2 were 3 ml each, while the rest of the procedure remained the same as that for cake.