Abstract:
comparison of nutritional value of nontraditional with commercial vegetables in Sindh. The questionnaire survey methodology was used to collect the data on the utilization and consumption of nontraditional and commercial vegetables in Mirpurkhas of Sindh province, Pakistan in 2014. On the basis of survey spinach, horse radish tree flowers, lambs quarter and gram leaves were collected in January, 2014 whereas, amaranthus was collected in the months of July-August, 2014 from district Mirpurkhas, packed with proper labelling and brought to the Institute of Food Sciences and Technology, Sindh Agriculture University Tandojam for processing and nutritional analysis. The edible parts of vegetables were washed and divided into five sets namely control, boiled, cooked, thermally dehydrated and shade dried.
The data of survey showed that gram leaves was the most popular nontraditional vegetable eaten frequent or occasionally by 82% respondents only 18% respondents never tasted or do not know this vegetable. Next vegetables which majority of respondent never tasted or did not know included amaranthus and lambs quarter. About 62% respondents never tasted or do not know horse radish tree flowers as vegetable while 38% respondents answered they eat occasionally.
The nontraditional (lambs quarter, horse radish tree flowers, gram leaves, amaranthus) and commercial (spinach) vegetables were analyzed for their nutritive, mineral, vitamin, phytochemical and chlorophyll composition. The highest moisture content (92.66%) was found in spinach under boiled method followed by 88.760% moisture content in the same vegetable at fresh (control). Maximum ash content (16.15%) in horse radish tree flowers followed by 10.56% ash content in amaranthus under thermally dehydration. Protein content was found greater (7.56%) in gram leaves under thermal dehydration method. However, minimum protein of 1.04% was found in spinach under boiling method. The maximum value of 3.85% in horse radish tree flowers under cooking method while minimum fat content i.e. 0.85 and 0.75% was found in spinach and lambs quarter, respectively at boiling method. The highest value (13.35%) of fiber was obtained in thermally dried sample of horse radish tree flowers whereas the lowest value was recorded in boiled sample of spinach. However, higher carbohydrate (68.62%) content was found in lambs quarter at shade drying. The nontraditional vegetables also contain organic acids (e.g. lactic acid, citric acid, acetic acid, tartaric acid) in all the selected vegetables. The nontraditional and commercial vegetables were also recorded with significant amount of vitamins and phytochemicals. The energy value was found lowest in fresh spinach (38.35 Kcal 100g-1) hence was also detected lowered in other processing methods as compared to nontraditional vegetables. The results of the sensory evaluation of the uncooked and cooked samples in present study revealed that in uncooked samples, horse radish tree flowers obtained highest scores in appearance, color, odor, texture, taste, overall acceptability and purchase i.e. 4.90, 4.70, 4.00, 3.90, 3.50, 3.80 and 3.80. While in traditionally cooked samples lambs quarter and gram leaves retained original color and thus obtained the highest scores in appearance and taste i.e. 3.70, 3.90 and 3.70, 3.50, respectively. Acceptability study by hedonic scoring showed that nontraditional vegetables (horse radish tree flowers, lambs quarter, and gram leaves and amaranthus) made by traditional cooking were most acceptable as compared with commercial vegetable (spinach). These nontraditional vegetables when consumed in cooked form could also be a good source of nutrients.
Principal component analysis revealed that the first seven principal components explained about 94.79% of the total variability in the observed parameters. Moisture, total solid, ash, fiber, carbohydrate, nitrogen free extract, energy value, acetic acid, citric acid, oxalic acid, tartaric acid, copper, iron, zinc, manganese, calcium, sodium and potassium resulted the most effective variables for the first principal component. Saponins, flavinoids, phenol and vitamin B3 were major contributors to second principal component, while tannins content was useful to define the third principal component.
It was concluded that the nutrient and bioactive contents obtained from selected vegetables seem to suggest that the vegetables have high potential to contribute to the nutritional and health status of local as well as urban communities in Sindh Pakistan. Their use in the communities should therefore, be promoted. Taking into account the amount of nutrient and bioactive content in the selected nontraditional vegetable, these plants could be valuable and important contributor to the diets of the people in Sindh, Pakistan.