Interactive effects of location x sampling time on organoleptic and nutritional properties of six maize genotypes

Abstract

Grains of three field corn varieties and their F₁ hybrids obtained by crossing to a standard sweet corn were sampled at two different intervals for their organoleptic properties and at three intervals for nutritional qualities. The objective was to determine the most appropriate time to harvest for green maize consumption and also detect changes which may have occurred in nutritional qualities in relation to time of sampling. Results obtained showed that location effect was significant (p < 0.01) for all organoleptic properties while time of sampling had significant effect on sweetness and texture. The interactive effects of locations x sampling time and variety x sampling time were significant for flavour, sweetness, texture and preference respectively.  With respect to nutritional qualities, there was an inverse relationship between grain protein concetration on one hand and nitrogen free extract as well as carbohydrate content, as sampling was delayed while crude lipid, ash and crude fibre remained relatively unchanged. The genotypes differed significantly for both properties with Suan-1-SR being superior to others for flavour and texture at the milk stage while Obatanpa x sweet corn was superior for grain protein concetration (17.1 and 15.34% at each location) also at the milk stage. Association among organoleptic properties were generally positive and significant at the milk stage thus emphasizing the importance of early harvesting for maize intended for green consumption.  However, association between most of the organoleptic properties and nutrient composition were non significant except those of ash content with flavour, texture and likeness which were negative and significant only at the milk stage.  This tends to corroborate earlier findings that consumer acceptability for green maize consumption may not necessarily be related to quality characteristics.