Date stamp labels on food often give confusion to consumers. Are they safe to eat? or should they be discarded once the date has passed? Most of us understand that once the date has passed, those food are no longer safe to consume. That is the general understanding.

However, inconsistency in date labelling has caused misunderstanding to consumers and consequently contributes to wastage of food. In survey conducted by Food Marketing Inst. (FMI) in 2011, to maintain food safety, 25% respondents discarded food based on sell by date, 37% discarded food after the used by date and 10% believe eating food past its best buy date is a serious health risk. 

Variations of terms on date label such as "Best Before", "Use Before", "Expiry Date", "Display Until" and etc. are indeed confusing to consumers. Below are some explanation of these common terms:

Best Before or Best-By
This is a suggestion to the consumer on which date the product should be consumed to assure for ideal quality.

Use-By or Expiry Date
This label is aimed at consumers as a directive of the date by which the product should be eaten; mostly because of quality, not because the item will necessarily make you sick if eaten after the use-by date. However after the use-by date, product quality is likely to go down much faster and safety could be lessened.

Display Until & Sell-By
This label is aimed retailers, and it informs them of the date by which the product should be sold or removed from shelf life. This does not mean that the product is unsafe to consume after the date. Typically one-third of a product’s shelf-life remains after the sell-by date for the consumer to use at home.

References

1. Newsome, R., Balestrini, C. G., Baum, M. D., Corby, J., Fisher, W., Goodburn, K., Labuza, T. P., Prince, G., Thesmar, H. S. and Yiannas, F. (2014), Applications and Perceptions of Date Labeling of Food. Comprehensive Reviews in Food Science and Food Safety, 13: 745–769. doi: 10.1111/1541-4337.12086
2. http://futurefood2050.com/food-waste-infographic-gallery/
3. http://msue.anr.msu.edu/news/understanding_date_stamp_labels_on_food
4. http://www.lovefoodhatewaste.com/node/2285