Sensory quality of tomato, carrot and wheat : Influences of growing systems

Abstract: The sensory variation in products, conventionally and ecologically grown has been described and the effect of sensory training on the reliability of the assessors has been evaluated.Ecologically grown tomatoes scored higher for sweetness while conventionally grown tomatoes scored higher for firmness. For total taste intensity, acidity and bitterness, there was an interaction between growing system and variety. In a controlled experiment, nutritiously poor growing substrate produced a low yield of sweet, firm and less juicy tomatoes. Nutritiously rich growing substrate produced a high yield of less sweet, less firm but juicier tomatoes. Late harvest resulted in an increase of total taste intensity and a decrease of the bitter taste of the tomatoes.Conventionally grown carrots scored high for carrot-taste, while ecologically grown scored high for bitter taste. In one out of two years conventionally grown carrots were sweeter and crunchier while ecologically grown carrots were harder. Conventionally produced wheat samples had significantly higher protein levels compared with ecologically produced wheat samples. The volume of the wholemeal bread was related to the protein content and there was a close relationship between volume and elasticity of the bread.It was observed that information on labelling as being ecologically grown caused an increase in product rating. For sweet tomatoes with high tomato taste intensity, the information on them being grown ecologically was less important for consumer preference. During training the variation in reproducibility within assessors decreased and the assessors' ability to detect differences between samples increased.