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Raw and germinated cowpea seeds (Vigna sinensis) were subjected to high-pressure treatment at 300–500MPa for 15 min. Standard analyses, i.e., determination of protein and starch content, protein solubility, starch availability as well as microscopic observation (SEM) were used in order to study biochemical and microstructural changes in treated seeds. In opposite to germination process, the high-pressure treatment of seeds did not evoke signiWcant changes in starch content (total and available). However, both the processes used signiWcantly aVected protein content (total and soluble). Pressurization of raw and germinated seeds evoked diversiWed eVect on the total protein content. Whereas, the germinated seeds and/or these high pressure-treated ones demonstrated signiWcantly higher content of soluble protein compared to raw material. The most distinct changes in microstructure of germinated seeds treated with pressure (500MPa/15 min) were observed, and they mostly were related to the alteration in protein structure., Spanish CICYT (AGL 2002-02905 ALI and AGL 2004-00886 ALI).

The present work studies the antioxidant capacity as well as the vitamin C and E contents of raw, fermented and germinated seeds of Lupinus albus L. var. Multolupa. Vitamin C was quantified by micellar electrokinetic capillary electrophoresis and vitamin E isomers by high performance liquid chromatography. The antioxidant capacity was determined by spectrophotometry and expressed as trolox equivalent antioxidant capacity (TEAC) and by liposome methods using phospholipids bilayers. Germination, in general, brought about an increase in the content of α-tocopherol, a decrease in the content of γ-tocopherol and did not affect the content of δ-tocopherol, which resulted in an increment in the vitamin E activity. Vitamin C increased sharply but gradually after germination. Fermentation caused a drastic reduction in the antioxidant vitamin content, vitamin C was not detected and tocopherol isomers decreased significantly. Germination processes caused a significant increase in antioxidant capacity (TEAC) of both hydrophilic and lipophilic extracts and fermentation produced slight changes or total reduction in TEAC, depending on process conditions. The peroxidation of egg yolk phosphatidyl-choline (PC) was inhibited by all lupin extracts in comparison with control assay. Germination was selected as a good treatment to increase antioxidant capacity and vitamin C and E contents.

Cowpea (Vigna sinensis L. var. Carilla) flours obtained by fermentation with inoculum Lactobacillus plantarum (PF) or with the natural microorganisms present in the flour (NF) and subsequent heat treatment in an autoclave were prepared to study the effect of fermentation on the antioxidant vitamin content and on the antioxidant capacity. Bacterial counts and pH values, vitamins C and E, carotenoids, glutathione (GSH), superoxide dismutase-like activity (SOD-like activity), peroxyl radical-trapping capacity (PRTC), lipid peroxidation in unilamillar liposomes, and Trolox equivalent antioxidant capacity (TEAC) were evaluated in raw and processed cowpea flours. ç-Tocopherol and ä-tocopherol were found in raw cowpea, whereas vitamin C and carotenoids were not detected. An increase in the vitamin E activity was observed in PF, whereas vitamin C and carotenoids were not detected in fermented cowpea flours. Fermentation or heat treatment in an autoclave after fermentation produced processed cowpea flours with lower PRTC, glutathione content, and SOD-like activity than those of the raw seeds. However, those processes increased the capacity to inhibit the lipid peroxidation in unilamellar lipoposomes and TEAC. According to the results obtained in this study, the fermentation of cowpeas (naturally or with L. plantarum) and fermentation and subsequent heat treatment in an autoclave are good processes to obtain functional cowpea flours having higher antioxidant capacity than the raw legume

The inositol phosphate content of naturally fermented cowpeas (Vigna sinensis var. Carilla) was studied using ion-pair HPLC and 1H NMR spectroscopy. The fermented flour was extracted with 0.5 M HCl, and the extract was purified and fractionated by ion-exchange chromatography. 1H NMR allowed for the identification of two monophosphates [Ins(1 or 3)P1 and Ins(4 or 6)P1], one inositol diphosphate [Ins(1,4)P2], three inositol triphosphates [Ins(1,2,6)P3, Ins(1,5,6)P3, and Ins(1,4,5)P3], one inositol tetraphosphate [Ins(1,3,4,5)P4], and one inositol pentaphosphate [Ins(1,2,3,5,6)P5]. Some of these isomers [Ins(1,4,5)P3 and Ins(1,3,4,5)P4] are considered to play important biological roles in intracellular signaling., We are grateful to the Spanish Comision Interministerial de Ciencia y Tecnologia (CICYT) for financial support of the project (AGL 2002-02905 ALI).

Natural fermentation and an inoculum containing 10% (vol/vol) Lactobacillus fermentum or Lactobacillus plantarum were used to obtain fermented flours from Vigna sinensis L. var. carilla seeds that had been washed with distilled water and dried at 55°C for 24 h. To optimize the fermentation parameters (lactic acid bacterium level, bean flour concentration, and fermentation time), several small-scale fermentation processes were carried out. On the basis of the results obtained, fermentor-scale bean fermentation by microorganisms present on the seeds (natural fermentation [NF]) or by inoculation with L. plantarum (PF) was carried out at 37°C for 48 h with a concentration of 300 g of bean flour per liter. The fermented flours (NF and PF) were also autoclaved. The levels of alpha-galactosides, inositol phosphates, trypsin inhibitor activity (TIA), soluble carbohydrates, starch (total and available), total available carbohydrates, thiamin, and riboflavin were determined for the processed cowpea flours, and microbiological studies were also carried out. The beans' levels of alpha-galactosides, TIA, and inositol hexaphosphate decreased by 95, 50, and 85%, respectively, for the NF flour and by 87, 27, and 85%, respectively, for the PF flour, while inositol pentaphosphate and inositol tetraphosphate were present in both fermented flours. The sucrose content decreased, and glucose, fructose, and galactose appeared as a result of fermentation. The levels of total available sugars and thiamin decreased by 2 and 12% and by 69 and 43%, respectively, while the riboflavin content increased by 106 and 94% for NF and PF flours, respectively. When NF and PF cowpea flours were heated in an autoclave for 20 min, TIA decreased further (by 80 and 56%, respectively). According to the chemical and microbiological results obtained in this study, fermentation with L. plantarum and autoclaving is an excellent process by which to produce a new functional food from the seed of a cheap legume (Vigna sinensis L. var. carilla)., This study was supported by Spanish Project AGL2002-02905 and constitutes part of R. Doblado’s Ph.D.

The kinetics of inositol phosphate degradation during the action of naturally occurring endogenous phytase for up to 90 min in pea and lentil flours has been studied, and compared with the addition of commercial phytase enzyme. In raw lentils IP6, IP5, IP4 and IP3 were present, whilst in peas only the presence of IP6 and IP5 was observed. Endogenous phytases were activated when legume flour was suspended in acidified water at pH 5.5 and 37°C, and significant differences between lentils and peas were found. IP6 suffered a sharp reduction in lentils and peas (81-91 and 73-93%, respectively), this reduction being slightly more pronounced after the addition of commercial phytase. The content of IP5 decreased in lentils (48-69%), and increased in peas, except when commercial phytase acted for the first 30 min, after which a reduction was found (23%). The content of IP4 generally decreased in lentils, except when endogenous phytase acted for 30 min when an increase was observed. However, in peas, IP4 appeared in high concentrations up to 60 min by the action of both endogenous and exogenous phytases. The content of IP3, on the other hand, did not change greatly in lentils. In peas it was not detected after the action of endogenous phytase enzyme and it appeared in a large amount after the action of commercial phytase. In order to obtain legume flour with low IP6 and IP5 contents and notable IP4 and IP3 contents, the action of naturally endogenous phytase for 30 min in lentils is recommendable, as well as the addition of commercial phytase enzyme for 60 min in peas., This work was supported by the Spanish Comision Interministerial de Ciencia y Tecnologı́a ALI-97-0636 and is part of the Ph. D work of J. R. Antezana.

The kinetics of soluble sugars (available sugars and α-galactosides) during the action of naturally occurring endogenous α-galactosidase for up to 90 min in lentil and pea flours has been studied, and it has been compared with the addition of commercial α-galactosidase enzyme. Raw lentil and pea seeds presented sucrose, raffinose, stachyose and verbascose, whilst ciceritol was only present in lentils. No monosaccharides were detected in either of the raw seeds. After the action of endogenous α-galactosidase or by the addition of commercial α-galactosidase, fructose, glucose and galactose were detected in legume flours. The action of endogenous α-galactosidase for 15-90 min in lentils or peas produced a reduction of sucrose (77% and 73-81%), raffinose (73-77% and 59-79%), stachyose (76-81% and 77%) and verbascose (100% and 70-83%), respectively. When commercial α-galactosidase was added to lentils or peas the observed decreases were in sucrose (77-73% and 62-64%), raffinose (61-68% and 41-48%), stachyose (80-85% and 67-91%) and verbacose (100% and 77-95%) respectively. The action of endogenous α-galactosidase or the addition of commercial α-galactosidase could produce lentil or pea flours with very small flatulence factors and, therefore, with a high functionality. According to these data, the optimal conditions to obtain lentil and pea flour with the lowest α-galactoside content were the addition of commercial α-galactosidase at 37°C in buffer pH 5.5 for 90 min. In these conditions the largest contents in fructose, glucose, galactose and sucrose were obtained., This work was supported by the project CICYT (ALI 97–0636) and is part of Ph D. of R. Doblado.

The effect of natural fermentation of flour and whole bean seeds (Phaseolus vulgaris) on the content of nutrients (protein, fat, starch, dietary fiber, vitamins B1 and B2) and antinutritional factors (α-galactosides, trypsin inhibitor activity and inositol phosphates) has been studied. After fermentation, total protein content decreased (2-15%) but the in vitro protein digestibility increased (4-8%) and the fat content did not change. In fermented bean flours, fructose and sucrose decreased (67-83% and 99-100% respectively), glucose increased (175-750%) and galactose was present at the concentration 1:4 g/ml (flour:water), but when whole beans were fermented none of these soluble sugars were detected. Total starch, available starch, insoluble fiber content decreased after fermentation (5-13%, 10-24%, and 5-26%, respectively), which was less pronounced in whole fermented beans. The soluble dietary fiber decreased (61-71%). The vitamin B1 content decreased (17-38%) and the vitamin B2 content increased (16-35%) after fermentation. Fe, P, Mg, Ca, and K decreased and Zn content did not change after natural fermentation. In either fermented flour or whole beans, the alpha-galactosides and IP6 decreased (99-100%, 7-39% respectively); however in fermented flour beans IP5 content did not modify or decrease and IP4 content could also increase. When whole bean grains were fermented no IP5 and IP4 was detected. TIA levels and tannins content decreased (58-71% and 61-70%) after fermentation. Natural fermentation of beans has been a very effective process for increasing functionality of Phaseolus vulgaris and the whole bean fermentation is very promising due to the lower cost. © Springer-Verlag 2001., This study was supported by the Comision Interministerial de Ciencia y Tecnología (AGL2000-1609-C02-01) (Spain) and Dirección de Investigación de la Universidad Simón Bolivar de Caracas (Venezuela).