Pg. 12-13 Determination of fruit quality of litchi cv. Mauritius in different orchards

Litchi (Litchi chinensis Sann.) cv. Mauritius is a popular export cultivar due to its attractive red colour and exotic flavour. Fruit quality parameters, such as juice acidity, soluble solids concentration (SSC), SSC:TA and skin colour are generally considered to determine the fruit quality at harvest. A multivariate analysis, canonical variate analysis (CVA), was used as a statistical tool to discriminate the orchards that produce good quality fruits from inferior quality fruits using twelve physical, five chemical and three sensory parameters. The CVA helped to determine the relative contribution of each parameter to the discrimination between orchards. The correlations and the plot of loadings of the variates indicated that fruit weight, skin colour, hue and fruit firmness are the main factors that discriminates orchard 3 from the other two orchards. The SSC and TA are the two quality parameters that discriminate between orchards 1 and 2.

Summary:

• Litchi cv. Mauritius is a popular export cultivar valued for its attractive red color and exotic flavor.
• Fruit quality parameters at harvest typically include juice acidity, soluble solids concentration (SSC), SSC:TA ratio, and skin color.
• The study used multivariate canonical variate analysis (CVA) with 12 physical, 5 chemical, and 3 sensory parameters to discriminate fruit quality between orchards.
• Key parameters distinguishing orchards were fruit weight, skin color (hue angle h0 and lightness L), fruit firmness, and consumer acceptability.
• SSC and titratable acidity (TA) mostly discriminated between two orchards that were closer in quality.
• Fruit skin color changes during maturation from green to yellowish pink to red, correlating with ripeness and consumer preferences.
• The CVA showed orchard 3 had fruits with higher hue values (more yellowish pink) but lower firmness and consumer acceptance.
• Strong correlations were found between odor and fruit pH/SSC:TA; taste and SSC:TA; skin color and consumer acceptability; and firmness and consumer acceptability.
• Negative correlations included skin color and lightness, firmness and hue, and TA with taste and pH.
• SSC:TA ratio is suggested as a practical chemical index to determine fruit quality at harvest.
• This research supports using combined physical, chemical, and sensory indices to evaluate and discriminate litchi fruit quality from different orchards for better quality control.
• The study was partly funded by the South African Litchi Growers’ Association and related industry programs.