First they’re sour, then they’re sweet: Exploring the berry-to-berry uniformity of blueberry quality at harvest and implications for consumer liking

Fruit quality parameters are typically reported and discussed as a conglomerate mean of many individual fruit. For berry crops, the concept of berry-to-berry uniformity in fruit size, texture, and flavor are also relevant to consumers, but has yet to be studied. We utilized the interquartile range (IQR) to represent fruit quality uniformity, and established the percentage of acceptability (%A) metric to integrate the mean and uniformity of each dataset. The first objective of this study was to compare fruit quality uniformity among six popular fruit crops. Blueberry had the lowest uniformity of TSS and TSS/TA among crops. The second objective was to assess whether blueberry cultivar, growing season, berry maturity, or harvest number impacted fruit quality uniformity. From 2022–2024, quality of individual berries was collected from multiple experiments performed in Michigan, USA. Cultivar, season, and harvest number greatly impacted the IQR of most parameters. Berry maturity mostly influenced the uniformity of TA due to changes in metabolism. We also sought to capture the relationship between the mean and uniformity of fruit quality parameters. The mean and uniformity (IQR) for berry mass, TSS, TA, and TSS/TA were significantly correlated, suggesting that the uniformity of diameter and firmness are not linked to ripening-related processes. Finally, we evaluated the uniformity of consumer sensory scores from one experiment and discussed the relevance of uniformity for the consumer liking of blueberries. In conclusion, uniformity is an important component of fruit quality in blueberry, and the IQR and %A should be utilized in future studies of fruit crops. • We characterized berry-to-berry quality uniformity in blueberry fruits. • Blueberry displayed poor uniformity of TSS and TSS/TA among small fruits. • Cultivar, season, and harvest number greatly affect blueberry quality uniformity. • Interquartile range is an ideal metric to capture fruit quality uniformity. • The % of acceptable fruit (%A) integrates the mean and uniformity of fruit quality.