Quality Attributes of Some Organic Versus Conventional Fruits and Vegetables in Ghana

The choice between organic and conventional food with regards to safety and quality has received attention over the last decade and this has become an important debate among professionals and scientists. The objectives of this work were to assess and compare the nutritional and physicochemical properties of some selected organic and conventional fruits and vegetables, and to determine the perception of consumers on organic and convention fruits and vegetables. Some organic samples (pawpaw, okro and pepper) were obtained from an organic farm in the Brong Ahafo Region and their corresponding conventional samples were also obtained from other farms. These samples were subjected to various forms of sample analysis to ascertain nutritional content, mineral composition and physicochemical properties. 200 questionnaires were also administered randomly to the general population to ascertain consumer perception on organic and conventional fruits and vegetables. On the perception index, majority of the respondents 89.50% had knowledge about organic foods whereas some section representing 10.5% did not know of it at all. Also, for conventional foods, 63.64% had knowledge of it whereas 36.36% did not know of it at all. In relation to the possible health risks, 9.24% and 34.45% admitted there could be health risk associated with organic and conventional foods respectively, whereas 53.78% and 27.73% respectively thought otherwise. In terms of moisture, there was a significant difference between organic and conventional samples of pepper (Capsicum annum L) and okro (Abelmoschus esculentus L.). There was no significant difference between moisture content of organic pawpaw (OPP) and conventional pawpaw (IPP) samples. Among the samples investigated, IPP had the highest protein content, followed by OP, OK, IK, OPP and IPP. There was significant difference between both organic and conventional samples in terms of ash and fat contents. The organic samples had averagely a good fiber-carbohydrate balance. With the exception of organic and conventional pawpaw samples, there was a significant difference between organic and conventional pepper and okro samples at p ≤ 0.05 in terms of the fiber-carbohydrate content. The potassium content of two (IK and IPP) out of the three conventional samples was very high as compared to their organic counterparts. This result underscores the fertilizer application mode of most conventional farming practices especially the application of the popular NPK (Nitrogen, Phosphorus and Potassium) fertilizer. On the average, the sodium content of all samples fell within the range most of which are close to the mean point. With the exception of organic and conventional pepper, there was a significant difference in pH value between pawpaw and okro samples. Despite the fact that both organic and conventional samples were of the same stage of ripening, their brix and refractive indices differed significantly as well at their acidity. The titrable acidity of the conventional sample was higher than the organic sample. Phenolics of both organic and conventional pawpaw samples were very close. This survey indicated that most people perceived that products from organic sources are not only safer but also much more enriched with nutrients for good health while on the contrary perceived conventional foods to have high risk of health related issues. Nutritionally, the proximate and physicochemical studies proved that the organic samples in most instances had higher contents of nutritional constituents specifically protein, fiber and carbohydrates and high phenolic and brix contents and the antioxidant potency of organic foods to be quite higher when compared to the conventional ones. The conventional samples however had higher constituents of the specific minerals (Potassium, sodium, magnesium and calcium).

Source: KNUST