3.2.4.1 Proximate Analysis Proximate analysis is done to determine the moisture content, total ash, crude fat, crude protein, crude fiber and total carbohydrate of each mayonnaise samples with different grape seed extract percentages.
3.2.4.1.1 Moisture Content
The moisture contents of mayonnaise samples with different grape seed extract percentages are determined by air oven drying according to the official AOAC method 930.15 (2003) with a slight modification (Babajide & Olatunde, 2010). First, dry the crucible with its lid in an air oven for 30 minutes at 100 °C and then leave to cool in the desiccator. Storing the crucible in the desiccator and handling the crucible with forceps are important steps to prevent obtaining the moisture from …show more content…
Before conducting the experiment, switch on the "MAINS" the Control Unit of Soxtec® Avanti System 2055. Set the appropriate temperature according to the solvent used at 135 ̊C to achieve the level of reflux solvent with 3 to 5 droplets per second. Select the appropriate program specified in the Control Unit to determine the time of boiling (15 minutes), rinsing (30 minutes), recovery (10 minutes) and pre-drying (5 minutes). Open the tap water to allow the reflux process occurred in a condenser at Extraction Unit. With the cooling process by water at about 15 ̊C, the water flow should be adjusted to the rate of 2 L / min to prevent boiling of solvents from the condenser. Preparation of sample is done with paved filter paper, weighing accurately 2.0 g sample (W1) into extraction thimble. Put a little cotton in the funnel of thimble to prevent the loss of the sample during extraction. The thimble prepared must be matched to its adapter and placed on thimble stand. With the aid of thimble handler, remove supporter of thimble by attaching thimble to the magnet in the extraction unit. Then, weigh the aluminium extractors cup which had been dried (W2) by using analytical balance. After that, fill the extractor cup with 70 ml petroleum ether solvent. By using the …show more content…
First of all, weigh 1.0 g of sample accurately in 250 mL digestion tubes by using analytical balance. After adding 1 tablet of Kjeltabs catalyst Cu 3.5 into the tube, add 12 mL of concentrated sulfuric acid, H2SO4 with caution, and shake the tube gently to moisten the sample with the appropriate acid. Connect the Exhaust system with the tubes which has been placed on the rack and ensure the aspirator system to start functioning. The rack and Exhaust system are locked to heaters block digester DS6 which has been preheated to 420 ̊C to begin the process of acid digestion. After about 5 minutes, turn off the aspirator system until acid fumes can be formed only in the top Exhaust system. Continue the digestion process until the formation of green clear sample in tube. Upon completion of the digestive process, move the rack from tubes to refrigerate the tube vertically for 10 to 20 minutes. After that, add 75 mL of distilled water carefully into the tube which has been cooled followed by the 50 mL of 40% sodium hydroxide, NaOH. In order to prepare the distillate samples, 25 mL of 4% boric acid with 10 drops Bromocresol green indicator are added to recipient solution in a 250 mL conical flask and subsequently placed into the Kjeltec 2100 Distillation unit (Gerhardt, Germany). Close the safety door after placing
3.2.4.1.1 Moisture Content
The moisture contents of mayonnaise samples with different grape seed extract percentages are determined by air oven drying according to the official AOAC method 930.15 (2003) with a slight modification (Babajide & Olatunde, 2010). First, dry the crucible with its lid in an air oven for 30 minutes at 100 °C and then leave to cool in the desiccator. Storing the crucible in the desiccator and handling the crucible with forceps are important steps to prevent obtaining the moisture from …show more content…
Before conducting the experiment, switch on the "MAINS" the Control Unit of Soxtec® Avanti System 2055. Set the appropriate temperature according to the solvent used at 135 ̊C to achieve the level of reflux solvent with 3 to 5 droplets per second. Select the appropriate program specified in the Control Unit to determine the time of boiling (15 minutes), rinsing (30 minutes), recovery (10 minutes) and pre-drying (5 minutes). Open the tap water to allow the reflux process occurred in a condenser at Extraction Unit. With the cooling process by water at about 15 ̊C, the water flow should be adjusted to the rate of 2 L / min to prevent boiling of solvents from the condenser. Preparation of sample is done with paved filter paper, weighing accurately 2.0 g sample (W1) into extraction thimble. Put a little cotton in the funnel of thimble to prevent the loss of the sample during extraction. The thimble prepared must be matched to its adapter and placed on thimble stand. With the aid of thimble handler, remove supporter of thimble by attaching thimble to the magnet in the extraction unit. Then, weigh the aluminium extractors cup which had been dried (W2) by using analytical balance. After that, fill the extractor cup with 70 ml petroleum ether solvent. By using the …show more content…
First of all, weigh 1.0 g of sample accurately in 250 mL digestion tubes by using analytical balance. After adding 1 tablet of Kjeltabs catalyst Cu 3.5 into the tube, add 12 mL of concentrated sulfuric acid, H2SO4 with caution, and shake the tube gently to moisten the sample with the appropriate acid. Connect the Exhaust system with the tubes which has been placed on the rack and ensure the aspirator system to start functioning. The rack and Exhaust system are locked to heaters block digester DS6 which has been preheated to 420 ̊C to begin the process of acid digestion. After about 5 minutes, turn off the aspirator system until acid fumes can be formed only in the top Exhaust system. Continue the digestion process until the formation of green clear sample in tube. Upon completion of the digestive process, move the rack from tubes to refrigerate the tube vertically for 10 to 20 minutes. After that, add 75 mL of distilled water carefully into the tube which has been cooled followed by the 50 mL of 40% sodium hydroxide, NaOH. In order to prepare the distillate samples, 25 mL of 4% boric acid with 10 drops Bromocresol green indicator are added to recipient solution in a 250 mL conical flask and subsequently placed into the Kjeltec 2100 Distillation unit (Gerhardt, Germany). Close the safety door after placing