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The purpose of this study is to evaluate the pattern of carotenoids distribution in three underutilized Malaysian ‘ulam’ or traditional vegetables in Malaysia (Averrhoa carambola, Manihot esculenta and Ipomoea batatas) and their valuable pro-vitamin A activities. These assessments will yield valuable knowledge and insight into the importance of these underutilized traditional vegetables and highlight their potential for applications in medicinal and functional colorant industries.

In this study, the authors have evaluated the distribution of carotenoid compounds in aerial organs of three underutilized traditional vegetables (Averrhoa carambola, Manihot esculenta and Ipomoea batatas). The content of the individual carotenoids were quantified using high-performance liquid chromatography (HPLC) and the organ with the highest accumulation of these compounds were identified. Their valuable pro-vitamin A activities were also reported to indicate their medicinal potential which can further be exploited as pharmacologically active natural colorants and in other applications.

In total, three major chromatographic peaks corresponding to lutein, violaxanthin and β-carotene were observed through HPLC. Among the compounds detected, lutein and β-carotene were the most abundant carotenoids found in both shoots and petioles of all three species. Violaxanthin was only detected in I. batatas shoots. Overall, carotenoid content was observed to be higher in the shoots than in the petioles, where I. batatas contained the highest amount of total carotenoid, followed by M. esculenta and A. carambola. The opposite trend was observed in the petioles, where A. carambola petioles had the highest carotenoid content, while I. batatas contained the least.

The distribution and abundance of these individual carotenoids suggested that the petioles contained the highest amount of carotenoid, contributing to its high pro-vitamin A activity, and could be potentially useful for medicinal application, as it can act as storage site that is not as prone to natural drying or degradation during harvest and sample storage. Future research work should include improvements in the extraction and purification procedures as well as robust identification methods which may lead to better detection and identification of other compounds that could attribute to its bioactivity, to complement the findings of the current study.

This analysis provides valuable information on the importance of underutilized traditional vegetables as important biofactories for sustainable production of valuable pigments (such as carotenoids) with medicinal benefits and can further be exploited in various industries, such as in formulation of functional natural colorants. This study also highlights the importance of petiole as a storage site of pharmacologically active compounds that is not as prone to natural drying or degradation during harvest and sample storage.

To date, there is no previous report found on comparative analysis of carotenoid content and quantification of individual carotenoid concentration in the edible aerial parts of Averrhoa carambola, Manihot esculenta and Ipomoea batatas, although they have been traditionally consumed as “ulam” in Malaysia. Therefore, the results reported in this study provide new insights on carotenoid accumulation in the selected ‘ulam’ species.

This paper aims to to explore the possibility of utilization of Ipomoea batatas as a novel binding agent for hot-set restructured meat products. Further, green coffee bean (GCB) extract was used as a natural ingredient to improve the lipid oxidative stability and storage quality of the developed restructured mutton blocks.

Restructured mutton blocks were used as a model and were prepared by incorporating different levels of I. batatas, namely, 1, 3 and 5 per cent and analyzed for various quality parameters. Restructured mutton blocks containing optimum level of I. batatas were further treated with GCB (1 per cent) extract as a natural ingredient and assessed for various lipid oxidative stability and storage quality parameters under refrigerated conditions (4 ± 1°C).

Restructured mutton blocks containing 3 per cent level of I. batatas were optimized as best on the basis of various quality parameters. Although a significant declining trend was observed in the sensory characteristics with storage; however, the products containing GCB extract showed significantly (p < 0.05) higher acceptability. The mean scores for overall acceptability for products with GCB extract on day 0 was 7.4 ± 0.1 and for control was 7.3 ± <0.1. Significantly (p < 0.05) lower thiobarbituric acid reacting substances (TBARS, mg malonaldehyde/kg) and free fatty acid (FFA, % oleic acid) values were observed for the products containing GCB extract. The mean TBARS and FFA values for products with GCB extract on day 0 were 0.2 ± <0.1 and 0.08 ± <0.1 and for control were 0.3 ± <0.1 and 0.09 ± <0.1, respectively. The restructured mutton blocks containing GCB extract also showed significantly (p < 0.05) lower values for various microbiological characteristics like total plate count (log cfu/g) and psychrophilic count (log cfu/g).

The results showed herein indicate a promising industrial application of I. batatas (3 per cent) as a binding agent for restructured meat products and GCB extract (1 per cent) as a novel natural ingredient for improved lipid oxidative stability and storage quality.

The purpose of this paper is to investigate the effect of partial substitution of wheat flour with sweet potato flour on the nutrient composition and sensory properties of bread.

Sweet potato flour was blended with wheat flour at 5, 10, 15, 20 and 25 percent levels of substitution for bread production. Proximate, minerals and antinutritional factors of the breads were investigated using AOAC methods. Sensory evaluation was carried out by a panel of 50 consumers. Data were subjected to analysis of variance and means were separated by Tukey’s comparison test at p <0.05. Results were reported as mean ± SD.

The nutritional and sensory quality of bread made from wheat flour supplemented with sweet potato flour at 5, 10, 15, 20 and 25 percent was investigated. Blending of sweet potato flour with wheat flour had significantly decreased the protein content (4.76–7.78 percent) while the ash (1.35–3.07 percent), crude fiber (0.24–1.03), carbohydrate contents (88.39–90.45 percent), iron, zinc, phosphorus and vitamin A contents were significantly increased ( p<0.05) with increasing sweet potato flour in the formulations. The tannin and phytate contents of the composite breads were low. Sensory evaluation of the breads revealed a mild reduction of the bread’s general acceptability with increase in the substitution level by sweet potato flour.

This study showed that the wheat flour used in making breads could be substituted with up to 15 percent sweet potato flour without compromising its nutritional quality, with only a mild reduction in sensory quality.

Patients with phenylketonuria (PKU) require a phenylalanine (Phe)-restricted diet due to its toxic effects on such subjects. Considering the low availability of specific foods for these patients, the purpose of this paper is to make breads with low Phe content while also conducting physicochemical and sensory analysis of the samples.

Five bread formulations with a common base were prepared, in which manioc – Manihot esculenta (T1); Baroa potato – Arracacia xanthorrhiza (T2); sweet potatoes – Ipomoea batatas (T3); potatoes – Solanum tuberosum (T4); and, finally, yacon potato – Smallanthus sonchifolius (T5) were added.

The physical analysis showed that the samples had similar weight, height and size values, indicating that the use of different types of vegetables does not compromise the final result of the preparation. The chemical analysis showed that the loaves were low in protein and Phe and, therefore, are considered safe preparations for patients with PKU. In the sensory analysis, all the preparations presented satisfactory characteristics for consumption, specially the one with the addition of potato.

The preparation of breads with low Phe content is a challenging task as it is necessary to exclude formulations with flours that present better technological performance. However, the results in this study showed that it is possible to get around the difficulties and obtain a viable product with easily purchased ingredients. It is known that sensory analysis with PKU patients as judges could have changed these results because their perception can differ from that of general population. The workgroup is continuing this study and we intend to take sensory analysis with PKU patients to future, as they have a pathology, the study needs special care and respectful ethical aspects.

PKU has a direct influence on the daily diet of the patient, interfering with life decisions that go form eating at their home to where and what to eat in environments out of their control. Therefore, creating specific preparations for such patients is a challenge that assists in adherence to dietary therapy.

The purpose of this study was to compare the nutrient and antinutrient content of two improved sweet potato varieties released for drought prone areas of eastern Ethiopia.

Matured roots of two sweet potato varieties, namely, Berkume and Adu, were collected from Haramaya University, Toni Research Farm, Ethiopia. The sweet potatoes were ground into flour following standard procedure. Thereafter, proximate, dietary minerals and β-carotene were determined by official methods of analysis. The tannin and phytate contents were determined by colorimetric methods.

The moisture, protein, fat, fiber, ash, utilizable carbohydrate and gross energy varied from 6.23-6.61 per cent, 2.07-2.76 per cent, 1.25-1.52 per cent, 1.04-1.16 per cent, 3.38- 5.32 per cent, 90.03-91.45 per cent and 382.18-388.07 Kcal/100 g in both the sweet potato varieties. Potassium content (176.17 mg/100 g) was reported to be the highest and registered in Berkume variety, while the lowest mineral content (2.18 mg/100 g) determined was zinc in Adu sweet potato variety. The highest total carotenoid content (3.39mg/100 g) was recorded in Berkume sweet potato variety. The tannin and phytic acid contents ranged from 9.98 to 12.94 mg/100 g and from 0.24 to 0.31 mg/100 g in Berkume and Adu sweet potato varieties, respectively.

This study showed that the Berkume sweet potato variety has high nutritional potential and less antinutrient contents as compared with the nutritional value of many other roots and tuber crops documented in the FAO database and hence can contribute to reducing malnutrition in resource-poor settings of Ethiopia. Further work needs to be carried out on developing value-added products from Berkume sweet potato variety for its extensive utilization.

The objectives of this study are to develop low cost weaning food for the economically disadvantaged nursing mothers and also to prevent protein energy malnutrition among the infants in Nigeria.

The blends (sweet potato and soybean flour) were prepared (homogenously) in the ratio of 90:10, 80:20, 70:30, 60:40 and 50:50 of sweet potato and soybean respectively. Triplicate samples of each blend were analyzed for moisture, fat, protein (N × 6.25), crude fiber and ash. Total lipid was estimated by petroleum ether extraction. Carbohydrate content was estimated by difference. Gross energy was determined. Water absorption capacity and bulk density were determined using standard procedures. The pasting characteristics of the flours were evaluated using a standard procedure. The sensory evaluation was carried out on the following parameters: taste, appearance, aroma, mouth (texture), colour and overall acceptability by a panel of ten members using a nine‐point hedonic scale.

The results of nutritional composition of the supplements showed protein 11.2–33.72 per cent, carbohydrates 42.91–76.51 per cent, fat 3.10–12.78 per cent, energy values 329.5–366.74 kcal/100 g and appreciable quantities of P, Zn, Fe, Mg, Ca, K and Na. The soy‐sweet potato flours had peak viscosity values between 180–365 BU. These values increased when cooled to 50°C, (420–760 BU). Results of this study showed that at 30 per cent soy flour supplementation, the meal could meet satisfactorily the recommended dietary allowances (RDA) for children of 1–3 years old, and that the developed soy‐sweet potato diets were nutritious, inexpensive and can easily be prepared from locally available raw food materials by using simple domestic processing techniques.

Evidence has shown that the cost of commercial weaning formula is very high and most of the low‐income family cannot afford to purchase this commercial weaning food and for such people an alternative low cost weaning formula is helpful.

Non-communicable diseases such as type 2 diabetes, hypertension, cancers and cardiovascular diseases have become a major health concern globally. As literature claims that frequent consumption of fruits and vegetables can delay the onset of type 2 diabetes and its complications, this paper aims to evaluate the potential hypoglycemic properties in five types of non-leafy vegetables (pumpkin, sweet potato, bitter gourd, onion and lady’s finger), which are commonly available in Malaysia.

Articles were identified through several main search engines, including Pubmed, Google Scholar, Taylor and Francis Online, EDS, Wiley, ScienceDirect and Scopus. The search was limited to selected keywords to refine the outcome.

All the five types of non-leafy vegetables demonstrate hypoglycemic properties to some extent. Emerging findings indicate that there are several phytonutrients in the non-leafy vegetables contributing to the hypoglycemic effects. To date, the underlying mechanism of action remains to be elucidated, although a number of potential mechanisms of action have been proposed in the literature.

This review provides some insights into the hypoglycemic properties in non-leafy vegetables. In addition, phytonutrients that are responsible for the hypoglycemic effects and their mechanism of action are also highlighted.

Acha and millet were cleaned, steeped in water, washed and spiced. Dry, granulated sweet potato was added and wet milled to produce a slurry. Two‐thirds of the slurry were gelatinized by the addition of boiled water and allowed to stand for two hours before the temperature was dropped to 50°C. The third part of the fresh slurry was added, mixed and allowed to stand for 12 hours, filtered through a cloth and sweetened by sucrose to produce kunun zaki. The effect of the two grains on the physiochemical properties (viscosity, total soluble solids, total solids, acidity, protein, fat, ash, moisture, carbohydrate and specific density) and sensory (colour, taste, odour, texture) quality were assessed. The physiochemical properties of the two grains were relatively similar. The mean scores for the flavour (odour and taste) are significantly different (P ≤ 0.05) with the acha based kunun zaki being more acceptable.

This study aims to assess the quality characteristics and acceptability of cookies from sweet potato–maize flour blends and to determine nutritional quality, color and palatability traits and to compare the effects with that of wheat cookies, so as to suggest a cost-effective production method to bakers and retailers. This would ensure food security, enhanced health, combat malnutrition problems and improve the production of the crops.

Cookies were prepared by the method reported by Okaka and Isieh (1990), Abayomi et al. (2013), Onabanjo and Ighere (2014) with modification. Flour (200 g) from each sample of different flour blends was used for the experiment. Sugar (80 g) was creamed with margarine (100 g) until light and fluffy constituency was obtained using Kenwood chef with initial minimum speed, and the speed increased stepwise until the mark of 6 on the chef indicator was attained. Whole egg (60 g) was added, then followed by flour (200 g), powdered milk (20 g), baking powder (0.1 g) and salt (1 g) were added and mixed until a stiff paste (batter) was obtained. The batter was rolled on a floured board using a rolling pin to a thickness of 0.2-0.3 cm. The rolled batter was cut into circular shapes with a cutter and arranged on a greased tray and baked at 1500°C for 20 minutes. The cookies were brought out, cooked and packaged in cellophane bag until used for laboratory analysis.

The results revealed that substitution of sweet potato flour with maize flour significantly (p < 0.05) reduced the protein from 6.8-4.4 per cent, moisture from 5.3-5.0 per cent, crude fibre from 3.4-2.5 per cent and fat from 9.8-8.5 per cent of the composite flours and the cookies. The ash and sugar contents were increased from 4.3-5.8 per cent for ash and 2.1-3.9 per cent for sugar with increase in sweet potato flour substitution. The calorific value of the cookies decreased from 457-397 cal/100 g as the percentage of sweet potato flour increased in the maize flour cookies. Sensory evaluation results showed that the colour, texture, taste and overall acceptability changed significantly (p < 0.05) with increase in sweet potato flour substitution. The optimum substitution level was 40 per cent; above this, the product becomes less acceptable to the consumer.

Fabrication and production processing machines that use sweet potato will be a great challenge.

This research is of value to the bakery industry or retailers. The optimum substitution level of sweet potato flour was 40 per cent, and it appears to be a promising measure from the view of practicability. The relative ease of getting sweet potato flour makes it superior to other imported flour like wheat and in reducing cost of importation of wheat to Nigeria.

This study aims to investigate the levels of some anti‐nutritional factors and minerals and the effect of boiling or roasting on selected commonly consumed Caribbean tuber crops.

Three commonly consumed tuber crops in the Caribbean namely: Yellow yam (Dioscorea cayenensis), Cocoyam (Xanthosoma sp.) and Sweet potato (Ipomea batatas) were harvested from farmers’ field in the Parish of Manchester, Jamaica and assessed in their boiled, raw and roasted forms for levels of some anti‐nutritional factors and minerals.

Zinc and iron levels were highest in raw Yellow yam, while the highest levels of calcium were observed in Sweet potato. The phytic acid to zinc molar ratio was higher than 15 in all the tuber crops in their raw and roasted forms. Boiling reduced this ratio to below 15 for Yellow yam and Cocoyam but still remained above 15 for Sweet potato. Cyanoglucoside level was highest in raw Sweet potato followed by Yellow yam and Cocoyam. Boiling or roasting reduced the levels of cyanoglucosides. Roasting greatly lowered the level of trypsin inhibitor activity compared to boiling. The highest level of trypsin inhibitor activity was recorded in the raw tubers, and slight reductions were observed upon processing.

Trypsin inhibitor was more stable to heat treatment compared to similar tubers grown in Africa. It may be beneficial to isolate and characterize trypsin inhibitor in these Caribbean tuber crops for utilization in nutraceutics.

This study shows that the two traditional processing methods were effective in lowering the levels of anti‐nutritional factors.