Yield and quality of asparagus spears as affected by crop method and product type

The research was carried out on green asparagus in a greenhouse in southern Italy with the purpose of verifying the chance to practice organic management to obtain both spears for ‘fresh’ market and industry, under the perspective either to use eco-compatible crop management or to limit the imports. The experimental protocol was based on the comparison between eight treatments obtained by the factorial combination of two crop systems (organic and conventional) and four spear types (‘fresh’, appetized in water, in oil, or as a patè). The conventional management led to the highest yield, as a consequence of the higher spear number plant-1, whereas the organic management resulted in the increase of both spear calibre and mean weight. Organic spears showed higher levels of dry residue, soluble solids and sugars, but a lower content of fibre. Between the three industrial types compared (patè, in oil, in water), ‘patè’ showed the highest values of dry residue, soluble solids and lipids, whereas the fresh spears had the highest content of sugars, acidity, vitamin C and fibre, the latter being not significantly different from ‘in water’ product which displayed the highest protein content. From this research, it arose that organic farming had a positive impact on some important quality parameters of asparagus spears. Moreover, the fresh spears and patè showed the overall better quality, compared to ‘in oil’ and ‘in water’ ones.