Assessment of consumer perceptions and preferences regarding fluid milk at the beginning and end of printed code date

Abstract Text: The objective of this study is to understand consumers’ expectations and actual sensory perceptions about fluid milk at the beginning and end of code.  Eleven sessions were carried out (n=103).  Sessions began with explanation of consent form and the experiment process, then panelists filled out a survey about demographics and milk purchasing and consumption behaviors.  Consumers were blindly served two pairs of milk samples (2% within 2-3 days of production (fresh) and 2% with 2-3 days to end of code (end); skim (fresh and end) and asked to indicate preference and the level of acceptability for each sample using a 7 point scale.  All samples tasted by consumers were simultaneously evaluated by a panel of 8 judges who were trained to evaluate milk quality attributes on a 15 cm line scale.  All milk was from the same source, processed on the same timeline for each session; milk was stored in the warehouse until transport to the sessions.  85 participants (82%) indicated they check for the farthest out code date more than half the time they shop.  However, upon tasting, consumers did not have a preference for 2% fresh milk over 2% end, or for skim fresh over skim end (p>0.05).  These findings were in agreement with their acceptability scores, which were 4.7 for skim fresh, 4.6 for skim end, 5.1 for 2% fresh and 5.1 for 2% end (p>0.05).  Trained panelists did not detect a difference in lacks freshness flavor in skim fresh (1.9 cm) or skim end (1.3 cm). Trained panelists also did not detect a difference in cooked, feed, flat, foreign or oxidized flavors for 2% or skim milk samples.  Trained panelists detected a significant difference in lacks freshness flavor of 2% fresh (2.3 cm) and 2% end (0.3 cm)(p<0.05). When the one off-flavored batch of 2% fresh milk was removed from analysis, trained panelists could not distinguish a difference in lacks freshness between 2% fresh (1.0 cm) and 2% end (0.4cm)(p>0.05).  After tasting and receiving an educational message about the meaning of code dates, 83% of consumers stated the information would impact their future purchases.  These results confirm that although many consumers go out of their way to buy the freshest milk, they cannot distinguish fresh milk from milk at the end of code. Additional research must be conducted to confirm impact of educational messages about code date on purchasing behavior.

Keywords: milk, sensory, code-date