Are there sources of nutritional data about UK supermarket products, by barcode?
The indexing by barcode does not need to be direct: if I have to implement a join with some other data to achieve that, that's fine.
Here is an example of the sort of information I am looking for (from http://www.tesco.com/groceries/Product/Details/?id=254381873):
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| Typical Values | 100g contains | 4 squares (17g) contain |
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| Energy | 2135kJ (510kcal) | 365kJ (90kcal) |
| Protein | 6.2g | 1.1g |
| Carbohydrate | 63.0g | 10.7g |
| Sugars | 62.0g | 10.5g |
| Fat | 25.3g | 4.3g |
| Saturates | 16.0g | 2.7g |
| Mono Unsaturates | 8.1g | 1.4g |
| Polyunsaturates | 1.1g | 0.2g |
| Fibre | 2.6g | 0.4g |
| Sodium* | 0.1g | trace |
| *Salt Equivalent | 0.2g | trace |
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Of course, it would be possible to scrape supermarket websites, but I prefer not to do that.