Recipient Organization
UNIV OF ARKANSAS
(N/A)
PINE BLUFF,AR 71601
Performing Department
Department of Agriculture
Non Technical Summary
Value-added food products are fresh or marginally processed merchandise whose worth has been augmented through the adding of ingredients or procedures that brand them added attractive to the consumer. It is a production/marketing strategy driven by customer needs and perceptions. Adding value to agricultural production contributes to the economic and environmental sustainability of both farms and the community. Adding value implies a degree of innovation that makes a product more desirable to consumers in terms of longer shelf life, improved functionality, better color, texture, flavor and more convenience. Value-added products can open new markets, create recognition and appreciation for the farm, and extend the marketing season. Consumer demand for ready-to-eat or ready-to-use types of prepared foods and minimally processed fruits and vegetables such as fresh-cut or pre-cut produce and salad mixes have increased due to shifts in consumer lifestyles and purchasing patterns. Benefits of value addition to farmers may include new products, optimized shelf-life and higher margins, with flow-on benefits to customers of product novelty, improved convenience, sensory appeal and food safety. Value-added products that will be considered include sweetpotato, sweetpotato leaves in relation to other food products. We will also use the sweetpotato and sweetpoato leaves as a food ingredient. Sweetpotato leaves are consumed in many countries both by humans and animals. There is a need to develop other forms of vegetables because the growth in ethnic populations in the US has contributed to demand product diversity within the produce section of the food stores. Also, food that was previously considered ethnic or regional in nature is increasingly being consumed by a broader portion of the population. A sweetpotato variety is regarded as an adequate leafy vegetable supplier when more biomass is shifted toward the maintenance of the above-ground dry matter accumulation in the canopy at the expense of tuber development. Frequent leaf harvest stimulates the growth of side shoots and vines. Leaves and young shoots can be harvested in 42 days after planting. Sweetpotato cultivars that have been developed for use as leafy vegetables are rich in calcium; however, the starch content of the leaves may be reduced as an indication of impairment of quality, but carotenoid content remains stable most of the time. Sweet potato leaves and shoots are good sources of vitamins A, C, and B2. Recent studies indicate that the leaves are exceptionally rich in vitamin A, polyphenolics, ascorbic acid, thiamin, riboflavin, niacin, phosphorous, iron, and calcium. Depending on the variety and growing conditions, sweet potato leaves are comparable to spinach in nutrient content. It accumulates less than 20% of the total oxalic acid found in spinach. Oxalic acid is an anti-nutritional factor that binds calcium and poses nutritional quality problems in many food products.Even when a significant protein content, sweetpotato leaves do not contain a complete amino acid profile. One of the shortcomings is the deficiency of lysine. When added with an energy-protein concentrate, sweetpotato vines maintained goat meat production and was stated to be mainly useful when the feed was rare. Ileal and total tract digestibility studies on growing pigs designated that sweetpotato leaves could improve dietary protein and amino acid supply in pigs fed with a low fiber diet. A latest research on pigs, which associated ileal digestibility of amino acids using a diet comprised of 25% fresh sweetpotato leaves versus a control diet with casein as the only protein source, determined that sweetpotato leaves could only substitute a segment of the protein naturally derived from a more costly plant-based source, such as soybeans, because of high fiber content and the occurrence of compounds that reduced amino acid digestibility. However, sweetpotato leaves are still possibly reasonably useful as a protein enhancement for pigs in the tropics where there is a close relationship between local feed bases, local crops, and animals-small-scale, mixed-farming schemes. Other antinutritional compounds reported in sweetpotato tops are tannic acid and oxalic acid at levels of 491 and 470mg 100g-1, respectively. Dairy heifers exclusively fed with sweetpotato tops were compared favorably with exclusive Lucerne and Napier grass feeding. Crude protein, Ca, and P levels were reported to be sufficient to sustain heifer growth. In a rice/sweetpotato cropping system, cattle fed with sweetpotato tops made more manure than the control cattle. Manure was then used as fertilizer for rice cultivation. Sweet potato cultivation is also widely distributed around the world, and sweetpotatoes are consumed mainly because of its carbohydrates. The industrial processing of sweet potatoes in products such as starch, flour, canned products, and purees generates an extraordinary amount of byproducts that have very little utilization at the moment. Leaves and vines are rich in nutrients and have the potential to be used for human consumption after cooking. Also, leaves and vines contain essential levels of bioactive compounds that could be recovered and used as social health and industrial products.
Animal Health Component
40%
Research Effort Categories
Basic
40%
Applied
40%
Developmental
20%
Goals / Objectives
Value-added food products are fresh or marginally processed merchandise whose worth has been augmented through the adding of ingredients or procedures that brand them added attractive to the consumer. It is a production/marketing strategy driven by customer needs and perceptions. Adding value to agricultural production contributes to the economic and environmental sustainability of both farms and the community. Adding value implies a degree of innovation that makes a product more desirable to consumers in terms of longer shelf life, improved functionality, better color, texture, flavor and more convenience. Value-added products can open new markets, create recognition and appreciation for the farm, and extend the marketing season. Consumer demand for ready-to-eat or ready-to-use types of prepared foods and minimally processed fruits and vegetables such as fresh-cut or pre-cut produce and salad mixes have increased due to shifts in consumer lifestyles and purchasing patterns. Benefits of value addition to farmers may include new products, optimized shelf-life and higher margins, with flow-on benefits to customers of product novelty, improved convenience, sensory appeal and food safety. Value-added products that will be considered include sweetpotato, sweetpotato leaves in relation to other food products. We will also use the sweetpotato and sweetpoato leaves as a food ingredient.Since it is known that the demand for green vegetables continues to rise worldwide, and also that sweetpotato leaves contain high-quality nutrients necessary for human health and are consumed as leaf vegetables. We hypothesize that a successful selection and evaluation of sweetpotato varieties for edible leaf vegetable production will enhance the national competence of the UAPB's faculty and students in agricultural research, hasten the opening of the US market for the sweetpotato products, and lead to increased revenue for the farmers, especially the limited-resource farmers in the Lower Mississippi Delta. Specifically, we will select sweetpotato varieties that will produce high-quality, nutritious leaf vegetables through plant breeding research and use the project opportunity to expose UAPB students to the international agricultural collaborative research process. Thus our research is guided by the following objectives: (a) Evaluation of designated sweetpotato varieties/genotypes concerning other commercial leafy vegetables for vitamins, mineral, and physiological functions, (b) to determine the nutrient, and anti-nutrient, namely oxalate and tannins levels of raw, cooked and dried sweetpotato leaves as compared to commercial leafy vegetables, (c) Prepare the crude extracts of the leaves of the selected specialty crops and sweetpotatoes, including its by-products using different extraction methods and identify antimicrobial and/or antioxidant compounds. Also, investigate their Organoleptic quality evaluations, (d). transmission of the knowledge to farmers, researchers, and food corporations in the United States, particularly to the small scale and limited-resource farmers in the Southeast Arkansas region, and (e) find out the cost-benefit of the products.
Project Methods
Evaluation of designated sweetpotato varieties/genotypes concerning other commercial leafy vegetables for vitamins, mineral, and physiological functions The assessment will be conducted on selected sweetpotato genotypes and check cultivars.To determine the nutrient and anti-nutrient levels of raw, cooked and dried sweetpotato leaves as compared to commercial leafy vegetables.The tops of the selected sweetpotato genotypes will be exposed to laboratory analyses. These materials will be used for the development of cooked and preserved specimens. Cooking will be done with and without the addition of lemon juice, and preservation will be done by direct sun-drying with and without salt. The leaves will be harvested from the same plot/greenhouse planted at the same time.The cooking of the leaves Two hundred grams of fresh-sorted leaves with a part of the petiole will be washed using tap water and the excess water drained. About 20 grams of finely chopped onion will be put in an aluminum cooking pan containing 20 ml of cooking oil and will be prepared at medium heat. The onions will be left to cook until they turned brown/yellow. About 200 g of the washed leaves and one medium-sized tomato cut into small pieces will be put on top of cooking vegetables and covered. The plants will be mixed every minute, and a small amount of regular iodized salt will be added. The pot will be covered and mixed two times, and then about 25 ml of lemon juice will be added. The pan will be covered, and cooking continued for one more minute. Another lot will be cooked in the same way, but no lemon juice. Total cooking time will be ten minutes, counted immediately after putting the vegetables in the pan. The same procedure will be applied to the commercial leafy vegetables namely spinach, kale, mustard green, and cabbage, to establish a comparison between them and the sweetpotato tops.Analyses for minerals, vitamins, anti-nutrient and other biochemical propertiesThe methods used for drying the sweetpotato leaves are as described by our previous articles. Each mineral will be individually analyzed using ICP. The device will be operated at standard conditions meant for the analysis of these elements.Prepare crude extracts of selected specialty crops and sweetpotatoes including its by-products using different extraction methods and identify antimicrobial, antioxidant, and other bioactive compounds, also Investigate the organoleptic qualities of food from sweetpotato tops. Determination of total flavonoids, total phenolic contents, antioxidant capacity (DPPH, ORAC and TEAC assay): The elegant ground samples will be determined as described in the previous paper. Identification and quantification of major phenolic compounds: Reversed-phase HPLC will be used to separate and quantify major phenolic compounds of samplesBacterial Strains and antimicrobial activity: The bacterial strains used as test organisms will be clinical or environmental strains of Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7.Organoleptic quality evaluations of the selected sweetpotato varieties leave and its products:Initial analysis of samples will be done before storage in the storage chamber. On each sampling day, sensory evaluation and color measurement of the samples will be determined. The sensory quality of samples will be evaluated by a panel of five trained judges (Islam and Jalaluddin, 2019). Five-panel members will be trained with prepared samples in advance. The samples will be coded with three-digit numbers. Off-odor will be evaluated immediately after opening the packages and scored on a five-point scale where 0 = none; 1 = slight; 2 = moderate; 3 = strong; and 4 = severe. The overall quality will be evaluated using a nine-point hedonic scale where 9 = like extremely; 7 = like moderately; 5 = neither like nor dislike; 3 = dislike moderately, and 1 = dislike extremely. The surface color of samples will be directly measured with a colorimeter. Three readings will be obtained for each replicate by changing the position of the sample to get uniform color measurements. The color will be recorded using a CIE L* a* b* color space, where L* indicates lightness, a* indicates chromaticity on a green (-) to the red (+) axis, and b* chromaticity on a blue (-) to the yellow (+) axis. A panel of ten judges will be used to evaluate the quality of sweetpotato varieties during storage (4°C) at two weeks intervals. The results of organoleptic quality will be scored for: color, odor, freshness and overall acceptability using a Hedonic scale test (7 = like extremely, 6 = like moderately, 5 = like slightly, 4 = neither like/dislike, 3= dislike slightly, 2 = dislike moderately, 1 = dislike extremely).Transmission of the knowledge to farmers, researchers, and food corporations in the United States, particularly to the small scale and limited-resource farmers in the Southeast Arkansas region. Cost-benefit analysis of sweetpotato leaves products.