Effect of Different Storage and Cooking Methods on Some Biochemical, Nutritional and Sensory Characteristics of Cowpea (Vigna unguiculata L. Walp)

Chemistry and functionalities of lake deposits and plant-based salts used in food preparations: A review

Lake deposits, plant-based ashes, filtrates and evaporites or alkaline salts are used traditionally in food preparations by local populations in Africa, Asia, South America, and Oceania. Depending on the context, traditional alkaline salts are used to reduce cooking times, improve rheological characteristics of starchy doughs, maintain the color of vegetables, improve the viscosity of sticky vegetables, and act as emulsifiers. This review highlights some of the relationships among chemical composition and physicochemical properties of traditional alkaline salts when used in solution as well as their functionalities. In addition, their potential toxicity and physiological effects are explored, which might lead to a better understanding of some previously unexplained functionalities and future trends in research, such as their impact on human health.

The effects of cooking on extractable tannin, phytate, sugars and mineral solubility in some improved Nigerian legume seeds/Efectos de la cocción sobre los taninos, fitato, azúcares y solubilidad mineral de algunas legumbres nigerianas

The effect of heat treatment on nutritional and antinutritional parameters in some improved Nigerian legume seeds is reported. The tannin (0.9-3.9 mg/g catechin equivalent) and phytate (0.5-3.0mg/g) contents were reduced by 11-84% and 13-32% respectively on cooking. Tannin content of Kersting's groundnut was reduced by 120%. Total sugar content was 8.7-16.7% in the raw samples but was also reduced by 8-30% on cooking. Stachyose was the predominant oligosac charide. Cooking reduced the sucrose content by 50-60% and the oligosaccharides by 36-59%. Total and available iron contents were 51-117 mg/kg and 7.2-16.2% respectively, total and ioniz able zinc content was low while total calcium and magnesium contents were high with adequate solubility during simulated digestion. Cooking improved iron availability and the ionization of zinc, calcium and magnesium by 19-100%, 22-104%, 18-83% and 11-61% respectively. There were significantly negative correlations between phytate tannin and mineral availability.

Cowpea (Vigna unguiculata L. Walp), a renewed multipurpose crop for a more sustainable agri-food system: nutritional advantages and constraints

The growing awareness of the relevance of food composition for human health has increased the interest of the inclusion of high proportions of fruits and vegetables in diets. To reach the objective of more balanced diets, an increased consumption of legumes, which constitutes a sustainable source of essential nutrients, particularly low-cost protein, is of special relevance. However, the consumption of legumes also entails some constraints that need to be addressed to avoid a deleterious impact on consumers' wellbeing and health. The value of legumes as a source of nutrients depends on a plethora of factors, including genetic characteristics, agro-climatic conditions, and postharvest management that modulate the dietary effect of edible seeds and vegetative material. Thus, more comprehensive information regarding composition, especially their nutritional and anti-nutritional compounds, digestibility, and alternative processing procedures is essential. These were the challenges to write this review, which focusses on the nutritional and anti-nutritional composition of Vigna unguiculata L. Walp, an emerging crop all over the world intended to provide a rational support for the development of valuable foods and feeds of increased commercial value. © 2016 Society of Chemical Industry.

Environmental effect on yield, composition and technological seed traits of some Italian ecotypes of grass pea (Lathyrus sativus L.)

BACKGROUND

Grass pea seeds are a good source of vegetable proteins, but the presence of toxic and antinutritional compounds represents a barrier to their large-scale use as food or animal feed. How much growing location and/or seasonal climate might affect the storage of these factors has been little investigated.

RESULTS

Fourteen Italian ecotypes of grass pea were cultivated in two locations in southern Italy characterised by different climatic conditions. The seven ecotypes with the best yields and/or seed quality were investigated for a further two growing seasons. From a statistical point of view the physicochemical and nutritional traits among ecotypes were not the same from one year to the next. Moreover, a significant positive correlation was found between β-oxalyl-diamino-propionic acid and trypsin inhibitor contents. The lowest levels of both these compounds were associated with the highest amount of rainfall during the plant vegetative cycle.

CONCLUSION

Principal component analysis of the data showed that the overall seed composition was affected by the growing location. Consequently, each grass pea genotype should also be carefully investigated in relation to different environments before being considered for release as safe for widespread human or animal consumption.

Evaluation of selected food characteristics of three advanced lines of Nigerian soybean (Glycine max (L.) Merr.)

The seeds of three promising advanced lines of soybeans (TGx 923-2EN, TGx 1019-2EN and TGx 1497-1D) which were part of a larger collection evaluated in agronomic field trials in Nigeria were selected for characterization of physicochemical properties, chemical composition, water absorption, cooking time and cooked texture as a function of soaking and cooking. Seed density, leached solids, swelling capacity and seed coat percentage were within a range of 1.15 to 1.26 g per ml, 1.00 to 1.26 g per 100 g, 80.25 to 84.35 g per 100 g and 6.6 to 10.1% w/w of dry beans, respectively. The total polyphenol content of the cream colored beans was similar (0.75 to 0.76 mg/g) but higher than the amount (0.60 mg/g) found in the white beans. Cooking times varied between 71 and 96 min without soaking and were reduced by about 32.0% following a presoaking treatment in water for 12 hours at room temperature (28 +/- 1 degrees C). Small seeds absorbed higher amounts of water during soaking and required less cooking time than larger seeds. Unsoaked beans required 40 min of cooking to achieve the same degree of cooked texture as the soaked beans cooked for 20 min, suggesting that cooking times and cooked texture for all lines were improved through soaking.

Hard-to-cook phenomenon in common beans--a review

Legumes are one of the world's most important sources of food supply, especially in developing countries, in terms of food energy as well as nutrients. Common beans are a good source of proteins, vitamins (thiamine, riboflavin, niacin, vitamin B6) and certain minerals (Ca, Fe, Cu, Zn, P, K, and Mg). They are an excellent source of complex carbohydrates and polyunsaturated free fatty acids (linoleic, linolenic). However, common beans have several undesirable attributes, such as long cooking times, being enzyme inhibitors, phytates, flatus factors, and phenolic compounds, having a "beany" flavor, and being lectins and allergens, which should be removed or eliminated for effective utilization. Grain quality of common beans is determined by factors such as acceptability by the consumer, soaking characteristics, cooking quality, and nutritive value. Acceptability characteristics include a wide variety of attributes, such as grain size, shape, color, appearance, stability under storage conditions, cooking properties, quality of the product obtained, and flavor. Storage of common beans under adverse conditions of high temperature and high humidity renders them susceptible to a hardening phenomenon, also known as the hard-to-cook (HTC) defect. Beans with this defect are characterized by extended cooking times for cotyledon softening, are less acceptable to the consumer, and are of lower nutritive value. Mechanisms involved in the HTC defect have not been elucidated satisfactorily. Attempts to provide a definitive explanation of this phenomenon have not been successful. The most important hypotheses that have been proposed to explain the cause of bean hardening are (1) lipid oxidation and/or polymerization, (2) formation of insoluble pectates, (3) lignification of middle lamella, and (4) multiple mechanisms. Most researchers have reported that the defect develops in the cotyledons. Recently, some authors have suggested that the seed coat plays a significant role in the process of common bean hardening. A better knowledge of cotyledon and seed coat microstructure may lead to a better understanding of the causes of seed hardness. In order to prevent the development of the HTC defect several procedures have been proposed: (1) appropriate storage, (2) controlled atmospheres, and (3) pretreatments. Probably, the most workable solution to the hardening phenomenon may be the development of materials less prone to HTC phenomenon. Decreasing cooking time, increasing nutritive value, and improving sensory properties of seeds with HTC defect would have great nutritional and economical impact.(ABSTRACT TRUNCATED AT 400 WORDS)