Reduction of some toxicants in Icacina mannii by fermentation with Saccharomyces cerevisiae

The effect of fermentation on the level of some toxic components (hydrocyanic acid, phytic acid and oxalic acid) of Icacina mannii paste was investigated. The results indicate that fermentation caused a decrease in the level of these toxicants ranging from 178 mg/kg to 70 mg/kg for hydrocyanic acid, 638 mg/kg to 463 mg/kg for oxalic acid and 49 mg/kg to 21 mg/kg for phytic acid. When the paste was supplemented with acitve cells of Saccharomyces cerevisiae there was a marked decrease in the level of the three toxicants ranging from 84 mg/kg to 16 mg/kg for hydrocyanic acid, 374 mg/kg to 88 mg/kg for oxalic acid and 24 mg/kg to 5 mg/kg for phytic acid. Supplementing the paste with yeast cells at a concentration of 7.5 g/kg before fermenting, resulted in approximately a 90% reduction in the level of the three toxic compounds after 144 hours of fermentation.     

The effect of fermentation on the nutrient status and on some toxic components ofIcacinia manni

The effect of fermentation on the nutrient status and on some toxic components ofIcacinia manni was investigated. Chemical analysis of both unfermented and fermented products revealed an increase in protein, ash and fibre content while the lipid and carbohydrate content showed a decrease. The results indicated that fermentation resulted in protein enrichment of the fermentedIcacinia manni mash. Fermentation was also observed to cause a marked decrease in the level of some toxic components (oxalic acid, phytic acid and hydrocyanic acid) of the product. The possibility of incorporatingIcacinia manni among the edible starchy plant tubers is discussed.     

The toxicants and phosphorus content of some Nigerian vegetables

The oxalate, hydrocyanic acid, phytic acid and phosphorus contents of twelve leafy vegetables were determined. The values ranged from 47.7–194.3 mg/100 g DM, 4.32–23.8 mg/100 g DM, 90–260 mg/100 g DM and 215–1110 mg/100 g DM, respectively. The ratio of phytic acid to phosphorus ranged from 13.9–90.7. The leaves contained low levels of hydrocyanic acid, while the oxalate, phytic acid and phosphorus contents were high. The results are discussed in terms of their clinical implications and nutritive values.     

Effect of blanching on the content of antinutritional factors in selected vegetables

The effect of blanching on the antinutritional content was studied in cabbage, turnip, collard, sweetpotato and peanut leaves. All the vegetables contained various amounts of phytic acid, tannic acid and/or oxalic acid. Tannic acid was found in largest amounts ranging from 1266.00 mg/100 g in cabbage to 491.00 mg/100 g in sweetpotato. Phytic acid content ranged from 0.31 mg/100 g in sweetpotato to 3.97 mg/100 g in collard. Oxalic acid was in trace amounts in cabbage and turnip; but high concentrations were found in sweetpotato (469.67 mg/100 g) and peanut greens (407.00 mg/100 g). Levels of both tannic acid and phytic acid were significantly (p<0.05) reduced by conventional and microwave blanching methods while oxalic acid levels were not significantly (p<0.05) reduced in most of the treatments by either of the blanching methods. In general, blanching is recommended as an effective method for reducing the antinutritional factors in green vegetables, however, further investigation on the heating times for both conventional and microwave blanching methods has been suggested.     

Effects of cooking,germination and fermentation on the chemical composition of Nigerian Cowpea (Vigna unguiculata)

The effects of cooking, germination, and fermentation on the chemical composition of cowpea were studied. There were noticeable trends in the protein, carbohydrate and crude fiber as a result of the different treatments. Both the germinated and fermented samples contained more ether extractable lipids than the raw and cooked samples. Untreated raw cowpea contained 5.9 mg/g phytic acid, 1.66 mg/g phytate phosphorus, 3.3 mg/g total phosphorus, 56.8 mg/g total sugar, and no reducing sugar. Cooking the dry beans at 100°C for 1 1/2 hours had little effect on the phytic acid and phytate phosphorus. There were, however, significant decreases in total phosphorus and sugars of the cooked beans. After germination for 24 hours, 48 hours and 72 hours respectively, there was a significant decrease in phytic acid and total sugar and increase in total phosphorus and reducing sugar. Similar results were also obtained when the dry beans was fermented for 24 hours, 48 hours and 72 hours respectively.     

Nutritional and toxic factors in selected wild edible plants

Nutritional (ascorbic acid, dehydroascorbic acid and carotenes); antinutritional and toxic components (oxalic acid, nitrate and erucic acid) were determined in sixteen popular species of wild edible plants which are collected for human consumption in southeast Spain. Ascorbic+dehydroascorbic acids contents were very high in several species, especially in Chenopodium album L. (155 mg/100 g). Carotenoid content ranged from 4.2 mg/100 g (Stellaria media Villars) to 15.4 mg/100 g (Amaranthus viridis L.). A range of values was found for oxalic acid from absence to 1100 mg/100 g of plant material. Nitrate contents ranged from 47 mg/100 g ( Salicornia europaea L.) to 597 mg/100 g (Amaranthus viridis L.). Low amounts of erucic acid were found in the Cruciferae family (Sisymbrium irio L. 1.73%; Cardaria draba L. 1.23%) and Plantago major L. 3.45%.     

Effect of processing method on the quality of cowpea (Vigna unguiculata) flour for akara preparation

An indigenous food mixture containing rice flour, milk coprecipitate, sprouted green gram paste and tomato pulp (2: 1: 1: 1 w/w) was developed and called a RCGT food mixture. It was autoclaved (1.5 kg/cm², 15min, 121 °C), cooled and fermented with 2% liquid culture (containing 10⁶ cells/ml broth). Two types of fermentations were carried out i.e. one step single culture fermentation [L. casei or L. plantarum (37 °C, 24 hr.)] and sequential culture fermentation [S. boulardii (25 °C, 24 hr.) +L. casei (37 °C, 24 hr.)]; [S. boulardii (25 °C, 24 hr.) + L. plantarum (37 °C, 24 hr.)]. All fermentations drastically reduced the contents of phytic acid, polyphenols and trypsin inhibitor activity while significantly improving the in vitro digestibilities of starch and protein. Sequential culture fermentations brought about further changes compared to one step single culture fermentation.     

Changes in phytates and HCl extractability of calcium,phosphorus, and iron of soaked,dehulled, cooked,and sprouted pigeon pea cultivar (UPAS-120)

UPAS-120, a high yielding and early maturing variety of pigeon peas releasedby the Department of Plant Breeding, CCS Haryana Agricultural University, Hisar contained a significant amount of phytic acid, i.e. 886 mg/100 g. When it was subjected to various domestic processing and cooking methods viz. soaking (6, 12, 18 h), dehulling, ordinary as well as pressure cooking and germination (24, 36 and 48 h), a drastic decrease in level of phytic acid with a remarkable increase in the HCl-extractability of mono, divalent, andtrivalent ions, like calcium, phosphorus, and iron occurred. Germination (48 h) was found to be the best method for decreasing the phytic acid content, i.e.35 to 39 percent less than the control and significantly (p<0.05) increasingthe non-phytate phosphorus and HCl-extractable phosphorus. Pressure cooking of soaked-dehulled pigeon pea also rendered equally good results. The calcium, phosphorus and iron contents of pigeon pea seeds were 197.3, 473.1, and 9.91 mg/100 g, respectively; some losses varying from 3 to 9 percent were noticed when the legume was subjected to soaking, cooking, and germination but the maximum losses, i.e. 23 percent, occurred when the seeds were dehulled. However, HCl-extractability of Ca, P and Fe improved to a significant extent when the pigeon pea seeds were soaked, soaked-dehulled, cooked and sprouted which may have been due to decrease in the phytate content followed by processing and cooking. The significant negative correlations between the phytic acid and HCl-extractability of minerals of processed pigeon pea strengthens these findings.     

Dephytinization of wheat bran by fermentation with bakers' yeast,incubation with barley malt flour and autoclaving at different pH levels

Wheat bran is an important source of dietary fiber but also contains considerable amounts of phytic acid, which is known to impair mineral absorption. The present study was conducted to investigate the phytic acid reduction in coarse and fine wheat bran by fermentation with the different levels of bakers' yeast (3, 6 and 9%) for 8 h at 30 °C, incubation with the different levels of barley malt flour (2.5, 5.0, 7.5 and 10.0%) for 8 h at pH 5.2 and 55 °C, and autoclaving at the different pH levels (pH 5.0, 4.5, 4.0 and 3.5) adjusted with acetic acid for 2 h. The phytic acid content of the wheat bran was effectively reduced by all treatments, and the phytic acid lost was in the range of 88.4–96.9%. Without addition of yeast or malt flour, or autoclaving without pH adjustment, the phytic acid content of the bran samples was reduced at most to 44.9% of the initial amounts under the investigated conditions. Increasing the concentration of yeast or malt flour or decreasing the pH towards 3.5 did not enhance the phytic acid reduction. The most reduction occurred after 2 h of yeast fermentation and malt flour incubation, and after 30 min of autoclaving, which made up 92–98% of the total phytic acid loss. Extending the treatment periods contributed nominally to further increase in the phytic acid reduction, and the rate of the phytic acid loss decreased progressively.     

Phytic Acid Level in Wheat Flours

The phytic acid content of refined (hand-made and factory-made) and whole (factory-made) wheat flours, much consumed in the Canary Islands, have been determined in this study. A total of 200 samples of flours from different types (100 refined and 100 whole) were analysed. The method proposed by Garcı́a-Villanova et al. (1982) was used for determination of phytic acid content in wheat flours. Most of the phytic acid concentrations are within the range 2–4 mg/g for the refined flours and 6–10 mg/g for the whole ones. The arithmetic mean obtained from all the samples studied is 3·77 mg/g for hand-made, refined flours, 2·96 mg/g for factory-made refined flours and 8·50 mg/g for the whole ones. On analysing the phytic acid content in all the flour samples, significant differences were observed for the different types of flour. Refined flours had a content lower than whole ones.     

Rabadi fermentation of wheat: Changes in phytic acid content andin vitro digestibility

Fermentation of raw as well as autoclaved wheat flour with buttermilk at 30, 35 and 40°C for 6, 12, 18, 24 ad 48h significantly decreased the level of phytic acid; maximum decrease was observed at 40°C for 48h. Starch as well as protein digestibility (in vitro) improved with an increase in temperature and period of fermentation. Phytic acid had a significant (P<0.05) negative correlation with digestibility (in vitro) of both starch and protein ofrabadi.     

利用贝叶斯法进行水稻籽粒植酸含量性状的QTL定位及互作分析

 利用水稻植酸含量差异较大的品种中花11(粳型)和LPA（籼型）为亲本杂交获得F2群体的172个单株,构建了含126个SSR和4个STS标记的遗传连锁图谱,利用贝叶斯（Bayesian）法对水稻籽粒植酸含量性状进行了主效应QTL定位和上位性互作分析。共检测到 3 个与水稻籽粒植酸含量性状有关的主效QTL,分布在第3、5和6 染色体的相应区间内,表型贡献率分别为538%、802%和462%,降低籽粒植酸含量的等位基因均来自亲本LPA。检测到10对上位性互作影响籽粒植酸含量, 分布于水稻第1、3、5、6、11染色体上,互作效应值为169～518,其表型变异的解释率为867%～2473%。     

植酸和氯离子对稻米品质的影响

 以原丰早为材料进行了在不同时期施用植酸与氯离子的试验。在水稻抽穗至成熟期间叶面喷施植酸，能抑制水解酶类的活性，减弱淀粉酶分解淀粉的反应，提高淀粉合成酶的活性，有利于淀粉合成，改善稻米品质。水稻齐穗期叶面喷施50、100 mg/kg 两种浓度的植酸，碎米率的平均值比对照低2. 8～23. 1个百分点，整精米率上升5～7个百分点；垩白等级、垩白率降低，乳白米粒减少，与对照相比差异显著；对碱消值、直链淀粉含量亦有影响。氯离子作为淀粉酶的激活剂，喷施后能抑制淀粉合成酶的活性，对稻米品质呈逆向效应。     

Tef: The Rising Ancient Cereal: What do we know about its Nutritional and Health Benefits?

This review covers the nutritional significance of tef cereal as compared to other common cereals with emphasis on carbohydrate content and starch digestibility, protein content, iron and zinc bioavailability and antioxidant potentials. Tef is a gluten free cereal and contains the highest iron and calcium among other cereals. It has high micro- and macro- nutritional profile and is becoming globally popular in the healthy grain food chain. Tef starch has a high gelatinization temperature, an essential precondition in the preparation of low glycemic index foods. There are significantly conflicting reports of iron content of tef ranging from 5 to 150 mg/100 g dm. The traditional fermentation of injera reduced majority of the phytic acid but no significant change to mineral bioavailability was observed. This review indicated that studies on starch digestibility, protein characterization, amylase and protease inhibitors, mineral bioavailability and antioxidant potentials are needed to further explore the nutritional and health benefits of tef.     

Optimization of the solid state fermentation process to obtain tempeh from hardened chickpeas (Cicer arietinum L.)

Solid state fermentation (SSF) represents a technological alternative for a great variety of cereals and legumes, orcombination of them, to improve their nutritional quality and to obtain edible products with palatable sensorial characteristics. The objective of this work was to find the best conditions of fermentation temperature and time to obtain tempeh from hardened chickpeas (Cicer arietinum L.) applying SSF. Response surface methodology(RSM) was applied over three response variables (phytic acid, in vitro protein digestibility and available lysine) to find best conditions of fermentation to carry out the process. A central composite experimental design with two factors [X₁ = temperature (31–36 ^°C) and X₂ = time (48–72 h)] in five levels (2 factorials,2 axial, I central) was used. Spores from Rhizopus stolonifer were suspended in distilled water (1 ×10⁶ spores/mL) and used as starter. According to regression models, minimum and maximum levels of the response variables were 1.24–2.66 mg phytic acid/g ofsample DM, 77.6–83.5% in vitro protein digestibility and2.18–4.63 g available lysine/16 g N. The superposition ofcontour plots of each one of the response variables allowedresearchers to find, graphically, the best conditions for the SSF process: 35.8 ^°C for 42.7 h.     

Variability in the antinutritional constituents in greengram Vigna radiata

Five greengram varieties, viz. Mg 161, M₃, Co₂, Pusa 8793 and Pusa baisakhi, were analyzed for phytic acid, tannic acid and trypsin activity. Significant varietal variation in tannin (310 to 400 mg percent), phytic acid (201.33 to 265.33 mg percent) and trypsin inhibitor activity (55.74 to 97.70 TIU/mg) were observed.     

Plant organic acids in fresh and ensiled forage plants

Timothy, red clover and white clover from two cuts and two stages of maturity and whole crops (WC) of barley, wheat and maize from three stages of maturity were analysed for individual plant organic acids (OAs) before and after ensiling in mini‐silos. Total OA levels, as previously reported, were generally lower in WC (14–70 g/kg dry matter) in comparison with leys (51–98 g/kg dry matter). Succinic, shikimic and fumaric acid levels were very low in all samples, while quinic, malonic, malic and citric acid constituted >90% of total OAs in all samples except maize. Maize had lower total OA levels than any other species but was the only one containing detectable levels of oxalic and aconitic acid. The sum of oxalic and aconitic acid decreased, however, from 89% to 35% of total OAs from early to late maturity, while there was a parallel increase in citric acid with increasing harvest date. Total OA level was unaffected in the ley crops by maturity, cut and species (p > .1), but among WC, wheat was higher than maize (p < .05) and also higher at early, than late maturity (p < .01). Silage total OA levels were lower than in parent crops (p < .001). Individual OA levels decreased by 38%–56% from ensiling, except for oxalic acid, which was unaffected, and succinic acid, which increased >7‐fold. Excluding succinic acid, which is also a fermentation product, average loss during ensiling was 44%.     

水稻籽粒不同部位植酸含量及其与稻米品质的相关性

 选用13个不同类型的水稻品种,对其籽粒不同部位植酸含量品种间差异及与稻米主要品质性状间的相关性进行了分析。结果表明,供试13个水稻品种米糠、糙米、颖壳、精米的植酸含量平均值分别为48.51、9.77、1.40和0.91 mg/g,而且不同水稻品种间籽粒不同部位的植酸含量存在极显著差异。在籽粒中,米糠中植酸积累最多,其次是精米,颖壳最少。米糠中植酸含量与糙米和颖壳中植酸含量呈极显著正相关。糙米和米糠中植酸含量与稻米蛋白质含量均呈显著的负相关,与千粒重均呈显著正相关。     

Phytic acid,in vitro protein digestibility,dietary fiber,and minerals of pulses as influenced by processing methods

The objective of this project was to determine the effect of various types of processing on selected nutrition related parameters of commonly consumed Indian pulses and soybean. Germination reduced the phytic acid content of chickpea and pigeonpea seeds by over 60%, and that of mung bean, urd bean, and soybean by about 40%. Fermentation reduced phytic acid contents by 26–39% in all these legumes with the exception of pigeonpea in which it was reduced by more than 50%. Autoclaving and roasting were more effective in reducing phytic acid in chickpea and pigeonpea than in urd bean, mung bean, and soybean. Germination and fermentation greatly increased the in vitro protein digestibility (IVPD). IVPD was only slightly increased by roasting and autoclaving of all legumes. Germination and fermentation also remarkably decreased the total dietary fiber (TDF) in all legumes. Autoclaving and roasting resulted in slight increases in TDF values. All the processing treatments had little effect on calcium, magnesium and iron contents.     

不同原料加工沱茶含氟量对比研究

本文以云南大叶种晒青毛茶为试验材料,通过对不同等级生沱茶原料、熟沱茶发酵阶段样、不同等级熟沱茶原料、生熟沱茶成品的氟含量、茶多酚、水浸出物对比分析,结合感官审评,结果表明:生沱茶原料氟含量随着原料粗老程度增加,随着茶叶级别降低氟含量呈上升趋势,二级为五级原料的76.41%;经拼配压制后的生沱茶氟含量为97mg/kg;发酵阶段样氟含量随发酵程度的加深呈下降趋势,降低幅度为4.72%;拼配成品熟沱茶的氟含量为119mg/kg。采用适当原料制作的生熟沱茶氟含量均远低于农业部行业标准的200 mg/kg。