Effect of process variables on trypsin inhibitor activity (TIA), phytic acid and tannin content of extruded African breadfruit-corn-soy mixtures: A response surface analysis

Flour samples of African breadfruit, corn and defatted soybean were extruded in a Brabender single-screw extruder (DCE 330, New Jersey). Effects of process variables on trypsin inhibitor activity (TIA) and other antinutritional factors (ANFs) were verified by response surface analysis (RSA). Blending improved the protein content of the mixtures but increased the ANFs. Extrusion cooking drastically reduced TIA, phytic acid and tannin content of the extrudates by 91%, 44% and 92%, respectively. The model developed produced the highest percent variation in TIA (80%) in comparison with either phytic acid (60%) or tannin (50%). Feed composition and screw speed were the most significant (P?0.05) process variables affecting TIA. Effect of feed composition was quadratic, while that of screw speed was linear. The quadratic effects of screw speed and feed composition on tannin and phytic acid were also significant (P?0.05).     

Effect of soaking,dehulling, and cooking methods on certain antinutrients and in vitro protein digestibility of bitter and sweet lupin seeds

Effect of several physical treatments (soaking, dehulling, ordinary cooking, microwave cooking, and autoclaving) on the level of antinutrients and in vitro protein digestibility of bitter and sweet lupin seeds were investigated. The raw bitter and sweet lupin seeds were found to contain phytic acid, tannins, trypsin inhibitor activity, and lectin activity, but α-amylase inhibitor was absent. Dehulling significantly increased the levels of phytic acid (PA), trypsin inhibitor activity (TIA), and tannins, but lectin activity was not changed. Also soaking in bitter (for 96 hr) and sweet (for 24 hr) seeds caused a significant increase in these factors except lectin activity. Cooking methods differently affected the levels of the antinutrients. Thus, PA increased but tannins were not changed, on the other hand TI and lectin activities were inactivated; ordinary cooking and autoclaving were the most effective in both seeds. For combination effect, soaking following cooking treatments significantly decreased PA, tannins, and lectin activity, but increased TIA in both seeds. Moreover, dehulling following soaking and cooking methods resulted in a significant increase of PA, TIA, and tannins. In vitro protein digestibility (IVPD) of raw bitter and sweet lupin seeds were 78.55 and 79.46%, respectively and it was improved by all processing methods; soakingdehulling after autoclaving was the most effective in both seeds. Although some treatments increased the level of antinutrients, they improved IVPD. Therefore, the studied antinutrients are not the only responsible factor for lowering IVPD.     

Effect of fermentation and dehulling on starch,total polyphenols,phytic acid content and in vitro protein digestibility of pearl millet

Two pearl millet cultivars: Standard and Ugandi, obtained from El Obeid Research Station, were used in this study. Investigation showed that the Ugandi variety had significantly (P⩽0.05) higher polyphenols and phytic acid contents than the standard and significantly lower in vitro protein digestibility (IVPD), (72.7 and 70.4% for the Standard and Ugandi, respectively), indicating lower nutritional quality. The two cultivars were fermented for 14 h at room temperature (30±2° C) and starch, polyphenols, phytic acid and IVPD were determined at 2-h intervals. Dehulling was found to cause a significant reduction in protein, polyphenols and phytic acid contents for the two cultivars. Fermentation and dehulling caused a significant increase in the IVPD for the two cultivars: 82 and 84% for the fermented ones and 79.1 and 78.6% for the dehulled samples.     

Factors affecting the in vitro protein digestibility of chickpea albumins

In vitro protein digestibility (IVPD) of chickpea albumins and its possible relationship to their structure and the presence of trypsin inhibitor activity (TIA) have been studied. Trypsin digestion of the albumin fraction under non‐reducing conditions was incomplete, while the reduction of inter‐ and intramolecular disulphide bonds caused an improvement in the accessibility of sites susceptible to trypsin digestion. Trypsin inhibitor activity in the chickpea albumin fraction was dependent upon both temperature and heating time. Although heating the albumin fraction at 100 °C for 30 min reduced the TIA by more than 50% with respect to the initial activity, an important TIA rate was attributable to heat‐resistant trypsin inhibitor. The TIA decrease was not related to an increase in the rate of IVPD. However, we observed a significant (P ≤ 0.05) increment in IVPD in the presence of β‐ME, confirming the essential role of disulphide bonds in stabilising the protein structure of the albumin fraction. © 2000 Society of Chemical Industry     

Effect of soaking and heat processing on the levels of antinutrients and digestible proteins in seeds of Vigna aconitifolia and Vigna sinensis

The effect of soaking, cooking and autoclaving on the levels of total free phenolics, tannins, phytic acid and in vitro protein digestibility (IVPD) were studied in Vigna aconitifolia and Vigna sinensis. Though soaking significantly reduced the content of tannins alone in V. aconitifolia, both total free phenolics and tannins were markedly reduced in V. sinensis. Greater loss of total free phenolics as well as tannins occurred under autoclaving compared to soaking and cooking in both the legumes investigated. In V. aconitifolia, soaking in distilled water for 6 h and cooking for 30 min reduced the phytic acid content by up to 43%. Maximum reduction in the level of phytic acid (36%) was observed under distilled water soaking compared to cooking and autoclaving in V. sinensis. Limited loss in content of phytic acid was noticed under autoclaving compared to soaking and cooking in both the pulses studied. In vitro protein digestibility (IVPD) of V. aconitifolia and V. sinensis was enhanced to 12.5 and 14.8%, respectively, under autoclaving. Of all the processing methods, autoclaving seemed to be the most efficient for reduction in content of the antinutrients, except phytic acid, and improving IVPD in both the pulses.     

Effect of fermentation on the nutritive value of maize

The effects of fermentation on protein, in vitro protein digestibility (IVPD), amino acid, total phenolics, phytic acid and colour values of four maize cultivars (two bi‐colour waxy corn and two super sweet corn), namely Jing Tian Zi Hua Nuo NO. 2, Jing Tian NO. 3, Bright Jean and Su Ke Hua Nuo 2008, were determined and compared with those of their unfermented counterparts. Results showed that fermentation caused significant increase in protein (43.5% largest increase), most kind of amino acid (131.5% largest increase in lysine content) and total phenolic content (23.4% largest increase), but significant reduction in phytic acid content (24.3% largest reduction) of four maize cultivars. The IVPD of four maize cultivars, except Suke2008, did not change significantly. Colour values of two waxy corn were resulted in the increase in a‐values and reduction in L‐values.     

Ileal digestibility of defatted soybean,lupin and chickpea seed meals in cannulated Iberian pigs: I. Proteins

Five castrated male Iberian pigs (100 ± 2 kg body weight) fitted with T‐shaped cannulas at the terminal ileum were used to determine ileal digestibility of legume seed meals. The diets were based on defatted soybean, lupin or chickpea seed meals and contained similar levels of digestible energy (14.2–15.1 kJ g^?1) and protein (107 g kg^?1). Protein‐free and a hydrolysed casein diets were used to study endogenous ileal amino acid flows. Chromium oxide (10 g kg^?1 diet) was added to the diets as an indigestible marker. Ileal flows in pigs fed the hydrolysed casein diet were different (p < 0.05) in amino acid contents and composition from those on the protein‐free diet. Ileal sialic acid flows in pigs fed lupin‐ or chickpea‐based diets were higher (p < 0.05) than those of animals fed soybean or casein diets. Among essential amino acids, only the apparent ileal digestibilities of phenylalanine and valine in lupin meal were lower (p < 0.05) than those in soybean. Apparent ileal digestibilities of lupin aspartate and proline, together with chickpea aspartate, were also lower (p < 0.05) than those of soybean. True ileal digestibility of nitrogen in pigs fed lupin or chickpea meals, calculated according to values from animals fed the protein‐free diet, was lower (p < 0.05) than that for soybean or casein. Among individual essential amino acids, only the true ileal digestibility of phenylalanine in lupin was lower (p < 0.05) than that in soybean. True ileal digestibility of nitrogen calculated according to values obtained with pigs fed a hydrolysed casein diet was not different among soybean, lupin or chickpea meals. Among essential amino acids, only the true ileal digestibilities of isoleucine and lysine in chickpea were lower (p < 0.05) than those of soybean. It is concluded that true ileal nitrogen and amino acid digestibilities of lupin and chickpea meals are comparable to those of defatted soybean in Iberian pigs. The results with protein‐free diets tended to underestimate endogenous protein secretion in pigs fed on diets containing protein. Copyright © 2005 Society of Chemical Industry     

Effect of glasswort (<Emphasis Type="Italic">Salicornia herbacea</Emphasis> L.) and rice (<Emphasis Type="Italic">oryza sativa</Emphasis> L.) on quality of <Emphasis Type="Italic">Ganjang</Emphasis> (Korean Soy Sauce)

Four types of meju were made from 100%(w/w) defatted soybean (DFS), a mixture of 80%(w/w) defatted soybean, and 20%(w/w) glasswort (DFS-G), a mixture of 80%(w/w) defatted soybean and 20%(w/w) rice (DFS-R), and a mixture of 60%(w/w) defatted soybean, 20%(w/w) glasswort, and 20%(w/w) rice (DFS-GR). Four types of Korean traditional soy sauce were prepared from the 4 types of meju. Mineral and antioxidant contents in the soy sauce made of DFS-G and DFS-GR were significantly higher than others. Citric, malic, succinic, lactic, and pyroglutamic acid contents in soy sauce made of DFS-R and DFS-GR were 1.3–1.5 times higher than others. Total nitrogen and free amino acid contents in soy sauce were correlated with DFS concentration in the meju. The bacterial community in the non-fermented meju-making ingredients was replaced largely by Bacillus sp. in the fermented meju. The use of glasswort and rice in the meju-making process did not alter the bacterial community responsible for the fermentation of meju.     

Phytic acid in Indian soybean: genotypic variability and influence of growing location

Phytic acid, the heat‐stable anti‐nutritional factor, was determined in 80 cultivars/strains of Indian soybean to identify genotypes that possess low concentrations of phytic acid. Variation of values of 28.6–46.4 g kg⁻¹ soy flour was observed. Information on the influence of growing locations with widely differing soil types on phytic acid content being scarce, phytic acid in the mature dry seeds of eight Indian soybean cultivars grown over four locations was evaluated. Variation in different varieties at different locations was 27.8–45.0 g kg⁻¹ soy flour. Averaged over eight genotypes, the maximum mean value for phytic acid was observed at Pantnagar and the minimum at Palampur. These differences in locational mean values for phytic acid can be explained on the basis of characteristics of the soils and environment. The higher mean value at Pantnagar may be attributed to higher soil organic phosphorus, nearly neutral pH and favorable temperature from flowering to maturity. However, the lower value observed at Palampur can be explained by the acidic nature of its soil, with lower maximum and minimum temperatures prevailing from flowering to maturity. Locational and genotypic × locational effects were found to be significant (p < 0.01). The results indicated that soil characteristics and soil environment play a significant role in the accumulation of phytic acid in soybean seeds. Copyright © 2005 Society of Chemical Industry     

Effect of natural fermentation on nutritive value and in vitro protein digestibility of pearl millet

Two pearl millet cultivars: Composite Population III, obtained from the Department of Agronomy, Faculty of Agriculture, University of Khartoum and Baladi, obtained from El Obeid Research Station, were used in this study. Investigation showed that Composite Population III is of higher tannin, total polyphenols and phytic acid and lower in in vitro protein digestibility (IVPD), which was found to be 60.5%. The two cultivars were naturally fermented for 36 h at room temperature (30±2 °C) and pH, moisture content, protein, tannin, total polyphenols, phytic acid content and IVPD were determined at 4-h intervals. Fermentation was found to cause a significant reduction in total polyphenols and phytic acid content for the two cultivars. Fermentation for 36 h at room temperature was found to cause no changes in tannin content of fermented dough for the two millet cultivars.     

Influence of Phytates on Protease and Dextrinogenic Amylase Formation

Phytates occurring in corn steep liquor (CSL) as an additional stimulatory factor for protease and dextrinogenic amylase formation was elaborated. Other products that contain a considerable amount of phytic acid phosphorus and low nitrogen content – comparing with CSL – such as corn steep precipitate (CSP), wheat bran, rice bran, and defatted one were successful replacers for CSL in protease and amylase production.     

Supplementation of pearl millet flour with soybean protein: effect of cooking on in vitro protein digestibility and essential amino acids composition

In vitro protein digestibility (IVPD) and amino acids profile of pearl millet (Dempy cultivar) supplemented with soybean protein (5–15%) were investigated. Supplementation of dempy flour with soybean protein steadily decreased IVPD with increasing the portion of soybean in the blend. The in vitro protein digestibilities of the cooked supplemented dempy flours were higher when compared with the raw ones, whereas the highest value was that of the 5% soybean protein. All essential amino acids of dempy flour were enriched on supplementation with soybean protein. The levels of amino acids increased with increasing the amount of soybean protein in the blend. Essential amino acids in dempy supplemented with 15% soybean are comparable to those in the FAO reference pattern. Supplementation increased significantly lysine to 1.5–2.4 folds. Essential amino acids content remained higher in the cooked composite flours when compared with the cooked native dempy flour.     

Effect of oil treatments on the levels of antinutritional factors in Callosobruchus chinensis (L.) infested stored pulses

Coconut, groundnut and mustard oil treated whole red gram, green gram and bengal gram were infested with Callosobruchus chinensis (L.), stored for 6 months, and observed at monthly intervals for antinutritional factors (phytic acid, trypsin inhibitor activity (TIA) and saponins). The values of phytic acid and TIA of treated and untreated pulses were similar at month one. The saponin content of green gram and Bengal gram were, however, higher in control than the oil treated pulses at month one. From month two to six the untreated controls had progressively more antinutrients than their oil treated counterparts. In mustard and groundnut oil treated pulses, the antinutrients remained static for 6 months, however, coconut oil treated pulse had increased antinutrients from end of month four onwards. The storage period was associated with the level of insect infestation which in turn influenced the antinutrient contents of pulses.     

Germination‐Assisted Enzymatic Hydrolysis Can Improve the Quality of Soybean Protein

This study aimed to investigate the effects of combined germination and Alcalase hydrolysis on the quality of soybean protein. Protein profiles, water solubility, foaming and emulsifying properties, thixotropic properties, and in vitro protein digestibility (IVPD) were tested, the chemical score (CS), essential amino acid index (EAAI), and protein efficiency ratio (PER) of soybean protein were also defined. The combined treatment of germination and Alcalase hydrolysis remarkably improved the solubility, emulsification activity index, emulsion stability index, and foaming capacity of soybean protein. Notably, a decrease in foaming stability was detected. The electrophoretic profile showed a weak breakdown of soybean protein during germination. However, a strong breakdown of protein was observed after the hydrolysis with Alcalase. The combined treatment also decreased the CS and EAAI of soybean protein, but only by 18%. Meanwhile, the IVPD and PER of soybean protein were significantly improved. Moreover, the protein of the germinated and hydrolyzed soybean flour demonstrated better swallowing properties. These findings indicated that the combined treatment of germination and enzymatic hydrolysis can improve the quality of soybean protein.     

Nutritional Quality of Vegetable Pigeonpeas [Cajanus cajan (L.) Millsp.]: Dry Matter Accumulation, Carbohydrates and Proteins

Since average dry matter accumulation of green pigeonpea seeds intended for use as a vegetable was 65.6% of the total in matured seeds, green seeds were collected prior to physiological maturity. Green seed contained less starch and more dietary fiber than did mature seed. Flatulence causing oligosaccharides were present in a lower amount in green seed. Trypsin inhibitor activity (TIA) was more in mature seed whereas green and mature seed differed little in chymotrypsin inhibitor activity (CIA). The mean value for in vitro protein digestibility (IVPD) of green seed was more than that of mature seed. The green seed had a greater amount of tryptophan and threonine and the sulphur containing amino acids, methionine and cystine. It is concluded that the green seeds of pigeonpea genotypes are nutritionally better than their mature seeds.     

Functional Properties of Defatted and Detoxified Madhuca (Madhuca butyraceae) Seed Flour

Functional properties of defatted and detoxified Madhuca (Madhuca butyraceae) seed flours were determined and compared with those of soybean flour. Soybean and detoxified Madhuca flours had higher water absorption capacities than defatted Madhuca flour. Due to the presence of saponins, the defatted Madhuca flour showed higher foaming capacity than the soybean and detoxified Madhuca flours.     

Effect of preincubation of sorghum flour with enzymes on the digestibility of sorghum gruel

A low-tannin sorghum cultivar M-35-1 was used in this study. Sorghum was germinated for 6 days and protease and amylase activities were measured every 24 h. Results showed that the 5th day germinated sorghum had a higher protease activity and a lower amylase activity. Sorghum flour was incubated for 30 min with the extract from germinated sorghum or with 0.01, 0.05 or 0.1 mg ml⁻¹ papain or trypsin prior to cooking in water. Results showed increase in in vitro protein digestibility (IVPD) with the 5th day germination extract. Pretreatment of sorghum flour with small amounts of papain or trypsin (0.01 mg ml⁻¹) improved the IVPD without affecting the paste viscosity, whereas the germinated sorghum extract led to very low paste viscosity. ©     

Simplified process for the production of sesame protein concentrate. Differential scanning calorimetry and nutritional,physicochemical and functional properties

The effects of a simplified production process on the yield, protein content and differential scanning calorimetric analysis of a sesame protein concentrate were studied. The results were compared with those for similar products obtained by the traditional method. The protein content of the (spray‐dried) sesame concentrate obtained by the simplified process (549 g kg^?1) was similar to that of the concentrates obtained by the traditional method (515–565 g kg^?1). Spray‐dried samples showed higher T_d and T_m and lower ΔH than freeze‐dried samples. In addition, the chemical composition, nutritional quality and physicochemical and functional characteristics of the sesame protein concentrate obtained by the simplified process were compared with those of a similar soybean product. The protein, lysine and calcium contents of the sesame concentrate were lower than those of the soybean concentrate, but the digestibility of the protein was the same for both products. The phytic acid content of the sesame concentrate diminished significantly, but was still higher than that of the soybean concentrate. The water absorption and protein solubility were higher for the soybean concentrate, whereas the oil absorption and viscosity at pH 3 were higher for the sesame concentrate. Copyright © 2003 Society of Chemical Industry     

PROCESSING AND ACCEPTABILITY OF FRIED CASSAVA BALLS ("AKARA-AKPU") SUPPLEMENTED WITH MELON AND SOYBEAN FLOURS

The processing and acceptability of fried cassava balls (“Akara‐akpu”) supplemented with melon and soybean flours were studied. Cassava flour, defatted soybean flour and cassava mash were produced. Some functional and chemical properties of the flours were determined. Akara‐akpu prepared from 100% cassava mash served as control; 100% cassava flour, 80% cassava flour + 20% defatted soybean and 70% cassava flour + 30% defatted melon flour were prepared. Akara‐akpu balls were subjected to chemical and physical analyses. Akara‐akpu prepared from composite flour blends had higher protein, fat, ash and energy value than Akara‐akpu from 100% cassava mash. The cyanide content and degree of starch gelatinization of Akara‐akpu prepared from 100% cassava mash (control) were higher than Akara‐akpu prepared from cassava mash plus composite flour blends. There was a significant difference (P ≤ 0.05) in weight and yield between Akara‐akpu prepared from 100% cassava mash (control) and cassava mash plus composite flour blends. There was no significant difference (P ≤ 0.05) in volume between Akara‐akpu made from control sample and those cassava plus composite flour blends.     

Effect of variety and processing on nutrients and certain anti-nutrients in field peas (Pisum sativum)

The effect of variety and processing (soaking, cooking and dehulling) on nutrients and anti-nutrients in field peas (Pisum sativum) was investigated. Analysis of variance showed that variety had a significant effect on crude protein, starch, ash, soluble dietary fibre (SDF), insoluble dietary fibre (IDF), total dietary fibre (TDF), trypsin inhibitor activity (TIA), minerals, phytic acid, sucrose and oligosaccharides. Soaking and cooking increased protein content, IDF, TDF, Ca, Cu, Mn and P in peas whereas ash content, Fe, K, Mg, Zn, sucrose and oligosaccharides were reduced. TIA was increased by soaking but reduced by cooking. Cooking was more effective than soaking in reducing oligosaccharides. Dehulling increased crude protein, starch, K, P, phytic acid, stachyose and verbascose content but reduced SDF, IDF, TDF, Ca, Cu, Fe, Mg and Mn.