Abstract: Quantitative comprehensive quality evaluation of high-acid apple is important to promote the rational planning of apple producing bases and industrial competitiveness. The overall quality of high-acid apples collected from different growing areas in 8 provinces in northern China from the year 2011 to 2014 was quantitatively evaluated. Taking into account that high-acid apple is consumed as a fresh fruit or as a juice, the main quality factors, including titratable acidity, soluble solids content, vitamin C content and juice yield, were divided to three categories: physiological, physical and appearance quality using the analytical hierarchy process (AHP) and K-means cluster analysis. A system to evaluate the overall quality of high-acid apple based on the selected indicators was established. The results showed that the quality of high-acid apples was relatively higher from Ningxia and Liaoning provinces; the quality of high-acid apples was varied from Shaanxi and Hennan provinces and was general from Gansu, Shanxi and Shandong provinces. The quality of most high-acid apples was good during 2011–2012 and varied during 2013–2014. The developed evaluation system could reflect the regional and inter-annual quality fluctuations of high-acid apple and the evaluation results could provide references for the structural adjustment of high-acid apple producing areas and the development of apple juice enterprises.

Key words: high-acid apple, Granny Smith apples, analytic hierarchy process, cluster analysis, comprehensive evaluation