Are organically grown apples tastier and healthier? A comparative field study using conventional and alternative methods to measure fruit quality

Summary

Since 1994 important supermarket chains in Switzerland successfully sell apples from verified organic production. However, in supermarkets customers often ask whether there are, apart from a more environmentally friendly production, objective arguments of inner fruit quality that justify the higher prices of organic apples.
In a field study with the ‘Golden Delicious’ cultivar, we harvested fruits of 5 pairs of organic/integrated fruit farms. The orchards within the pairs were less than 1 km from each other and were similar in micro climate, soil conditions and planting system. Maximum distance between the pairs was 180 km. To measure inner fruit quality we investigated at the beginning and at the end of cold storage (i) standard parameters (firmness, sugar, malic acid, mineral elements etc.); (ii) taste parameters by repeated panel tests; (iii) components that are good for human health (phenols, selenium, fibres, vitamin C and E) and (iv) fruit «vitality quality» by holistic approaches using image forming technique (crystallisation in copper chloride, and chromatography after Pfeiffer), degradation tests and feeding preference tests with laboratory rats.
All fruit samples of organic orchards had significantly firmer fruit flesh (14%) and had 15% higher taste marks than conventional ones. P-content was 31% higher (p < 0.01) in organic apples and was closely correlated with technical quality (r2 = 0.93) and sensory score (r2 = 0.69). Content of phenols (mainly flavanols) was 19% and image forming quality 60% higher in organic apples. The picture producing method distinguished 100% correctly the organic and integrated samples and was closely in line with technical quality (r2 = 0.68).
The results show that organically grown apples can have an outstanding inner quality. However, for generalizable conclusions more extensive studies are necessary.