Effects of various water or hydrothermal treatments on certain antinutritional compounds in the seeds of the tribal pulse, Dolichos lablab var. vulgaris L

Nutritional and nutraceutical potential of rice bean (Vigna umbellata) -a legume with hidden potential

In the recent years there has been paradigm shift in global agriculture for the exploration of different underutilized crops as future potential crops. Rice bean [Vigna umbellata (Thunb.) Ohwi and Ohashi] one of the lesser known pulses among Vigna species has gained attention during last decade as food and nutritional security crop. Rice bean seeds are well-balanced source of beneficial constituents such as protein, carbohydrates, minerals, vitamins, polyunsaturated fatty acids (PUFAs) and anti-oxidants for health benefits and combating malnourishment in human. In the present investigation, seeds of 15 diverse rice bean accessions from north-western Himalayan region were analyzed for nutrients, anti-nutrients and nutraceutical traits. Significant differences were observed among genotypes for different traits. The rice bean genotypes revealed variation for major quality traits including total carbohydrates (50.56-56.87%), crude protein content (22.56-25.97%) and lipid content (1.87 to 3.17%) with the higher proportion of linolenic acid followed by linoleic acid which are nutritionally desirable PUFAs. The genotype IC-548758 revealed higher proportion of desirable quality traits. Among protein fractions, globulins and albumins constituted major seed storage protein fraction in rice bean seeds. The wide range variation was also observed for anti-nutrients like including raffinose family oligosaccharides (RFOs), phenolics, tannins, trypsin inhibitor (TI), phytic acid, lipoxygenase activity and saponin content among genotypes. Insignificant correlation among iron, zinc, magnesium and manganese revealed good selection accuracy for genetic biofortification program in rice bean. In summary, the genotype IC-548757, IC-548760 and IC-548770 revealed lower proportion of anti-nutrients, whereas, the genotype IC-548759 and IC-548757 revealed higher level of free radical scavenging activity indicating nutritional and nutraceutical superiority of these genotypes. Overall, the study revealed nutritional superiority of genotype IC-548770, IC-548758 and IC-548760 with balanced proportions of nutrients and anti-nutrients. Rice bean legume has the potential to support more sustainable and resilient food and nutritional security in future. Our study highlights the potential of different rice bean genotypes as functional ingredients for future food and nutritional security programmes.

Autoclaved and Extruded Legumes as a Source of Bioactive Phytochemicals: A Review

Legumes have been consumed since ancient times all over the world due to their easy cultivation and availability as a low-cost food. Nowadays, it is well known that pulses are also a good source of bioactive phytochemicals that play an important role in the health and well-being of humans. Pulses are mainly consumed after processing to soften cotyledons and to improve their nutritive and sensorial characteristics. However, processing affects not only their nutritive constituents, but also their bioactive compounds. The final content of phytochemicals depends on the pulse type and variety, the processing method and their parameters (mainly temperature and time), the food matrix structure and the chemical nature of each phytochemical. This review focuses on the changes produced in the bioactive-compound content of pulses processed by a traditional processing method like cooking (with or without pressure) or by an industrial processing technique like extrusion, which is widely used in the food industry to develop new food products with pulse flours as ingredients. In particular, the effect of processing methods on inositol phosphates, galactosides, protease inhibitors and phenolic-compound content is highlighted in order to ascertain their content in processed pulses or pulse-based products as a source of healthy phytochemicals.

Optimization of soybean processing into kinema, a Bacillus-fermented alkaline food, with respect to a minimum level of antinutrients

AIMS

Optimization of traditional processing of soybeans using response surface methodology (RSM) to achieve a minimum level of antinutritional factors (ANFs) in kinema.

METHODS AND RESULTS

Central composite rotatable designs were used to optimize the processing stages of kinema preparation. In each stage, the linear or quadratic effects of independent variables were significant in minimizing ANF levels. The predicted optimum condition for soaking was when the raw beans-water ratio was 1 : 10, and the soaking temperature, time and pH were 10°C, 20 h and 8·0 respectively. Here, tannins content (TC), phytic acid content (PAC) and trypsin inhibitor activity (TIA) decreased (P < 0·05). While haemagglutinating activity (HA) level remained unchanged (P < 0·05), total biogenic amines content (TBAC) increased. The optimum condition for cooking was optimally soaked beans-water ratio of 1 : 5, and cooking pressure and time were 1·10 kg cm(-2) and 20 min respectively. Here, TC, PAC, TIA and HA decreased (P < 0·05), but TBAC remained unchanged compared to optimally soaked beans. TC and HA went below the level of detection. The optimum condition for fermentation was obtained when inoculum load was 10(3) total cells g(-1) grits, and fermentation temperature and time were 37°C and 48 h respectively. Fermentation of optimally cooked beans caused a reduction (P < 0·05) of PAC. While TIA remained unchanged (P < 0·05), TBAC increased. In kinema, TC, PAC, TIA and HA decreased (P < 0·05) over raw beans by 100, 61, 71 and 100% respectively. Good agreement was observed between predicted values and experimental values.

CONCLUSIONS

The processing treatments significantly minimized the level of ANFs in soybeans.

SIGNIFICANCE AND IMPACT OF THE STUDY

RSM was successfully deployed to obtain the optimum condition for kinema-making with a minimum level of ANFs without impairing sensory attributes of the product. The results are useful for commercial production of kinema.

Making use of guava seed (Psidium guajava L): the effects of pre-treatments on its chemical composition

The guava processing industry in Malaysia produces by-products in the form of seed core and peel. These by-products can be regarded as underused resources but there are concerns about their composition that prevent their use in the food and feed industries. This study aims to analyze the respective effects of heat treatments (boiling or autoclaving) and germination periods on the nutritional composition and phytochemical content of guava seeds. The guava seeds were found to contain 618, 78, 72, and 5 mg/g dry weight total dietary fiber, fat, protein, and ash, respectively. The tannin and saponin contents, but not the phytic acid content, were below the respective anti-nutritional thresholds. The heat treatments did not affect the total dietary fiber and ash contents but reduced all other chemical components to different extents (15-91%). Boiling did not reduce the phytic acid content substantially but autoclaving caused a reduction of 91% to a level below the anti-nutritional threshold. Germination for 14 days caused a significant reduction in nutrient contents in the range of 16-79%. Germination also reduced the phytic acid content by 90% in the seed but did not significantly affect the saponin content. Thus, guava seed can be treated thermally or germinated to manipulate its chemical composition to enable its use in the food and feed industries.

Peptides derived from dolicholin, a phaseolin-like protein in country beans (Dolichos lablab), potently stimulate cholecystokinin secretion from enteroendocrine STC-1 cells

Peptides derived from soybean beta-conglycinin and pork protein stimulate cholecystokinin (CCK) secretion from the enteroendocrine cells (EECs) and suppress food intake. Here we examined CCK-releasing activities from the enteroendocrine cell line STC-1, in peptides derived from underutilized legumes, and found much higher activity in the peptic hydrolysate of Country beans (CBP) compared to that from other legume-derived peptides including beta-conglycinin peptone. Active components in CBP were separated into acetonitrile-soluble fractions, but the activities were abolished after pronase treatment. To identify the Country bean protein containing the active peptides, Country bean protein extracts in an alkaline solution (CBE) were fractionated based on isoelectric point or molecular weight. Peptones prepared from CBE fractions containing a 51 kDa major protein stimulated CCK release, but other fractions did not. N-Terminal sequence analysis indicated that the 51 kDa protein is a phaseolin-like globular protein, and we designated this protein dolicholin. These results indicate that Country bean-derived peptides are very potent legume peptides in stimulating CCK secretion from EECs and that the stimulant peptides originate from dolicholin, a newly identified phaseolin-like globular protein in Country beans.

Alternative food/feed perspectives of an underutilized legume Mucuna pruriens var. utilis--a review

Mucuna pruriens var. utilis, an underutilized tropical legume has a nutritional quality comparable to soya beans and other conventional legumes as it contains similar proportions of protein, lipid, minerals, and other nutrients. The beans have been traditionally used as a food in a number of countries, viz., India, Philippines, Nigeria, Ghana, Brazil, and Malawi. Recently, the velvet beans are exploited as a protein source in the diets of fish, poultry, pig, and cattle after subjected to appropriate processing methods. Although the velvet beans contain high levels of protein and carbohydrate, their utilization is limited due to the presence of a number of antinutritional/antiphysiological compounds, phenolics, tannins, L-Dopa, lectins, protease inhibitors, etc., which may reduce the nutrient utilization. Unfortunately, even though many researchers all over the world working on Mucuna, only scanty and conflicting information are available regarding its utilization as a food/feed and no scientific gathering to date has focused on the food/feed applications of Mucuna. Hence, the present review has been emphasized on the nutritional potential of this underutilized, nonconventional legume and current state of its utilization as food/feed for both human beings and livestock throughout the world.

Effects of soaking temperature and soaking time during preparation of water extract of tea on anticlastogenicity against environmental tobacco smoke in the sister-chromatid exchange assay

Water extract of tea (WET) was prepared by soaking green tea at different temperatures for various periods of time and was used to test whether the soaking temperature and soaking time during the preparation of WET influence the content of polyphenols and the anticlastogenicity of WET against environmental tobacco smoke (ETS). Five major polyphenols in WET were measured. Extractable-respirable particulate (ERP) was obtained from ETS-contaminated indoor air (ERP-ETS). The sister-chromatid exchange assay (SCE) was utilized to evaluate the clastogenic effects of ERP-ETS and the anticlastogenic effects of WET. The results indicate that ERP-ETS is clastogenic and WET has significant anticlastogenic effects on ERP-ETS. The content of polyphenols and the anticlastogenic potential of WET depended on the soaking temperature and soaking time during WET preparation. At the soaking temperature of 80 degrees C, an increased soaking time was correlated with a higher percentage of polyphenols and a concomitantly enhanced anticlastogenic efficacy. By contrast, at the soaking temperature of 100 degrees C, a longer soaking time was associated with a higher percentage of polyphenols concomitant with a lower anticlastogenic efficacy. The data suggest that, besides polyphenols, and additional material(s), which may be partially inactivated at 100 degrees C, is contributing to the anticlastogenicity of WET.