Sample | Sample | Sample | Pair 1 | Pair 2 | Average |
Number | Description | Vitamin C (mg/100ml) from label | Vitamin C (mg/100ml) | Vitamin C (mg/100ml) | Vitamin C (mg/100ml) |
1 | The Juice Company Orange Juice Smooth Pure Squeezed Fruit (Aldi) (opened at the start of practical | 26 | 29 | 26 | 27.5 |
2 | The Juice Company Orange Juice Smooth Pure Squeezed Fruit (Aldi) left open for 1h at room temperature | 26 | 28 | – | – |
3 | The Juice Company Orange Juice Smooth Pure Squeezed Fruit (Aldi) left open for 24h at room temperature | 26 | 29 | ||
4 | The Juice Company Orange Juice Smooth Pure Squeezed Fruit (Aldi) left open for 24h in the fridge at 4C | 26 | 24 | – | – |
5 | The Juice Company Orange Juice Smooth Pure Squeezed Fruit (Aldi) left open for 24h with bicarbonate soda The Juice Company Orange Juice Smooth Pure Squeezed Fruit (Aldi) left open for 24h with bicarbonate soda | 26 | 23 | – | – |
6 | The Juice Company Orange Juice Smooth Pure Squeezed Fruit (Aldi) opened at the start of practice and boiled for 5 mins at 100C | 26 | 29 | – | – |
7 | Tropicana smooth Orange juice opened at the start of practical | 36 | 33 | – | – |
8 | Sainsbury’s Smooth Orange Juice UHT (Blue Carton) from concentrate opened at the start of practical | 20 | 38 | – | – |
Q1. Tabulate the main group findings (you can only have one table and this table must fit a single page – think about how the table should be presented and what additional information must come with the table; you do not need to present data on your blanks and standards).
Q2. What were the four main findings of this practice as a whole?
Q3. How do the measured amounts of vitamin C on the orange juice samples open only at the start of the practical compare to the values found on the food tables and the food labels? Are they different? Why? (note: you need to address possible limitations regarding the data present on the Food Composition Tables and also experimental procedure).
Q4. Using appropriate literature, explain the effect of the different test conditions on vitamin C stability and resulting vitamin C levels. Based on your answer what is the best way to store orange juice?
Additional notes:
In relation to your write-up, be critical of the findings. Find out first what the effect of leaving juices exposed to room temperature or open inside a fridge is, what the effects of adding bicarbonate soda are, what the effects of boiling are on vitamin C. If it’s not what was observed on the day, ask yourselves why not. Don’t simply accept the values measured in this practice as the truth.