Tuesday, October 15, 2019

Food chemistry lab report about Philadelphia cheese

Food chemistry about Philadelphia cheese - Lab Report Example All the results given below were found experimentally and then compared with those given by McCance and Widdowson. Methodology The experiments were carried out by reference to a given set of methods (see Appendix 1), although some changes had to be made, and some sections had to be omitted. For example, Philadelphia cheese does not contain any vitamin C or sugar, and as such those experiments were not undertaken. Between experiments, the cheese was kept refrigerated as instructed by the packaging. To prepare the Philadelphia for use, all that was required was to remove an appropriate sample of cheese and place this in the appropriate receptacle ready for use. Results Moisture Content of Food Mass of tin (g) Mass of tin + sample (before) (g) Mass of tin + sample (after) (g) Sample mass (g) % Moisture 24.56 27.29 25.37 2.74 29.70 24.20 27.61 25.33 3.42 33.20 25.10 27.46 25.87 2.36 67.10 Mean 24.62 27.45 25.53 2.84 43.33 Standard Deviation 0.45 0.16 0.30 0.53 20.66 Calculations used: (t in+sample)initial sample – (tin+sample)final mass x 100 = % Moisture mass of sample Ash Content of Food Mass of cruicable (g) Mass of cruicable + sample (before) (g) Mass of tin + sample (after) (g) Sample mass (g) % Ash 11.50 14.45 11.54 2.95 1.44 10.59 13.42 10.63 2.82 1.42 9.96 12.82 9.97 2.86 0.36 Mean 10.69 13.56 10.72 2.88 1.08 Standard Deviation 0.77 0.82 0.79 0.06 0.62 Calculations used: final mass-crucible mass x 100 = % ash mass of sample Determination of the protein content of food Mass of sample (g) Titre /ml Factor (from ‘Pearson’) %N % Protein in 0.32 1.96 6.38 0.86 5.47 0.34 0.99 6.38 0.41 2.60 0.33 2.11 6.38 0.90 5.71 Mean 0.33 1.69 6.38 0.72 4.59 Standard Deviation 0.01 0.61 0.00 0.27 1.73 Calculations used: Titre x 0.0014 x 100 = N% mass of sample Titre x 0.0014 x 100 x Factor = Protein % mass of sample Fat analysis by Buchi method    Sample weight (g) Empty cup weight Cup weight with fat Grams of fat per 100g sample    7.61 29.60 32.47 37.7 1    7.34 29.22 32.83 39.18 Mean 7.48 29.41 32.65 38.45 Standard Deviation 0.19 0.27 0.25 1.04 Calculations used: cup weight with fat – empty cup weight x 100 original sample weight Final results table: Experimental Values % McCance & Widdowson Values % Moisture Content 0.43 0.58 Ash Content 1.08 2.40 Protein 4.59 8.60 Fat 38.45 31.00 Carbohydrate 12.55 Trace Discussion The results gained experimentally were calculated in a similar way to those found in Atwater and Bryant’s tables that were published in 1904, all obtained by difference. The water, fat and protein content were all calculated and then subtracted from 100 to give a carbohydrate value. This is different to the McCance and Widdowson values, and this shows in some of the results. The experimental value for the ash content was 1.08%, which is only very slightly different from the given value of 2.40%. This suggests that the ash content measurement used (see Appendix 1) was fairly accurate. The standard devi ation for this value was only 0.62, which is very small, again suggesting that this measurement is accurate and very consistent. The moisture content found, 0.43%, was also very similar to the given value of 0.58%. However, the standard deviat

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