Phytase Treatment Research Articles

Study on gastric digestion behavior of phytase-treated soybean protein: A semi-dynamic digestion method

The digestive characteristics of plant proteins are crucial for their nutritional value and utilization efficiency. In this study, an in vitro semi-dynamic digestion model was employed to investigate the gastric digestion process of soybean protein after treatment with phytase. The results found that phytase treatment reduced the phytate content in soybean proteins (22.83 ± 0.09 to 8.72 ± 0.07 mg/g), shifted its isoelectric point towards the alkaline range by 1 pH unit, and significantly improved its solubility at pH 4.0. Particularly for protein sample treated with phytase after acid precipitation, the formation of aggregates during digestion was weakened, resulting in a significantly higher digestion rate compared to untreated SPI, with digestion being at least 15 min faster than SPI. This study provides a strategy for preparing soybean protein with faster digestion and weaker clot-forming ability during digestion, which offers insights for the application of soybean protein in clinical nutrition products and specialized medical foods.

Comparative study of different biological processing methods on nutritional composition and bioactivity of whole‐grain wheat

AbstractBackground and ObjectivesBiological processing is considered one of the most effective technologies used to eliminate adverse traits and improve the quality of cereal. To compare the effects of different biological processing methods on the nutritional value and bioactivity of whole‐grain wheat (WGW), solid‐state fermentation (SSF), germination (GT), solid‐state fermentation (SSF), germination (GT), and phytase treatment (PT) were performed.FindingsAfter biological processing, protein, insoluble dietary fiber, and bound flavonoid contents significantly increased, while phytate, bound phenolic, and free flavonoid contents obviously decreased. The molar ratio of phytate content to mineral content, including PA/Ca, PA/Fe, and PA/Zn, significantly reduced by 13.8%–42.0%, 8.4%–73.4%, and 17.9%–45.0%, respectively, suggesting the improvement of mineral bioavailability. The greatest reduction of phytate content was found in WGW after PT. In comparison to SSF and PT, GT significantly improved phenolic content and 2,2‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonic acid) and 1, 1‐diphenyl‐2‐picrylhydrazyl free radical scavenging abilities of free phenolic extract in WGW. As compared to GT and PT, the ORAC of the free phenolic extract in WGW obviously improved after SSF with strains of Lactobacillus plantarum, Saccharomyces cerevisiae, and Monascus sp.ConclusionsOverall, SSF, GT, and PT showed high efficiency in phytate degradation, and GT and SSF, in particular, improved the nutritional value and bioactivity of WGW.Significance and NoveltyThis study provides data supporting the use of different biological processing methods based on different objectives when preparing WGW products.

Impact of Fermentation, Autoclaving and Phytase Treatment on the Antioxidant Properties and Quality of Teff Cookies.

Teff [Eragrostis tef (Zucc.) Trotter] is an underutilised cereal crop grown mainly in Ethiopia and Eritrea. It is an excellent source of dietary fibre, vitamins, minerals and bioactive compounds. However, it also contains a high amount of phytic acid, which is an antinutrient and reduces the bioavailability of minerals and proteins. To improve the nutritional quality of teff, the phytic acid content should be reduced by an effective dephytinisation method. In this study, various dephytinisation methods (fermentation, autoclaving and phytase treatment) were used to dephytinise teff flour. Undephytinised and dephytinised teff flour was mixed into wheat flour (0-40 %) to improve the functional properties of cookies. Twenty different cookie formulations were prepared according to 4x5x2 factorial design. The physical, chemical, nutritional and sensory properties of the cookies were investigated. Among the dephytinisation methods, fermentation produced the most effective reduction in phytic acid mass fraction (181 mg/100 g), followed by phytase treatment (198 mg/100 g). The protein, fat, Fe and Zn content and antioxidant activity of cookies enriched with dephytinised teff flour were comparable to cookies fortified with undephytinised teff flour. Moreover, the dephytinised teff cookies had lower phytic acid mass fractions. The cookies containing 40 % teff flour had higher antioxidant activity and nutritional quality than the control wheat cookies. The use of dephytinised teff flour reduced the spread ratio and the a* and b* values of cookies compared to undephytinised flour. Cookies containing fermented and phytase-treated teff flour had a harder texture than cookies containing undephytinised flour. In addition, as the amount of teff flour increased, the spread ratio values of cookies gradually incrased while their hardness decreased. Overall acceptability scores of cookies containing 10-20 % teff flour were similar to the control. To the best of our knowledge, this is the first study to determine the quality of cookies containing dephytinised teff flour. The data highlight the potential of dephytinised (especially autoclaved and phytase-treated) teff flour (up to 20 %) as a functional ingredient to enrich the mineral content and antioxidant capacity of foods. Furthermore, this study shows that fermentation, autoclaving and phytase treatment can be used to improve the nutritional quality of grains.

Estimation of Iron Availability in Modified Cereal β-Glucan Extracts by an in vitro Digestion Model.

For cereal-based foods rich in dietary fibers, iron bioavailability is known to be poor. For native cereal β-glucan extracts, literature has demonstrated that the main factor impacting the bioavailability is phytic acid, which is often found in association with dietary fibers. During food processing, β-glucan can undergo modifications which could potentially affect the equilibrium between phytic acid, fiber, and iron. In this study, an in vitro digestion was used to elucidate the iron dialysability, and hence estimate iron availability, in the presence of native, chelating resin (Chelex)-treated, oxidised, or partially hydrolysed oat and barley β-glucan extracts (at 1% actual β-glucan concentration), with or without phytase treatment. It was confirmed that pure, phytic acid-free β-glucan polysaccharide does not impede iron availability in cereal foods, while phytic acid, and to a smaller extent, also proteins, associated to β-glucan can do so. Neither Chelex-treatment nor partial hydrolysis, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) or NaIO4 oxidation significantly influenced the phytic acid content of the β-glucan extracts (ranging 2.0–3.9%; p > 0.05). Consequently, as long as intrinsic phytic acid was still present, the β-glucan extracts blocked the iron availability regardless of source (oat, barley) or Chelex-treatment, partial hydrolysis or NaIO4-oxidation down to 0–8% (relative to the reference without β-glucan extract). Remarkably, TEMPO-oxidation released around 50% of the sequestered iron despite unchanged phytic acid levels in the modified extract. We propose an iron-mobilising effect of the TEMPO product β-polyglucuronan from insoluble Fe(II)/phytate/protein aggregates to soluble Fe(II)/bile salt units that can cross the dialysis membrane. In addition, Chelex-treatment was identified as prerequisite for phytase to dramatically diminish iron retention of the extract for virtually full availability, with implications for optimal iron bioavailability in cereal foods.

Impact of Phytase Treatment and Calcium Addition on Gelation of a Protein-Enriched Rapeseed Fraction

Rapeseed press cake was upcycled as a protein-enriched ingredient through dry fractionation. The protein-enriched fraction contained higher amounts of phytic acid compared to press cake, and phytase treatment was applied to decrease the phytic acid content from 6.8 to 0.5%. The effect of phytase treatment leading to the release of cations was also mimicked by extrinsic calcium addition. Both phytase treatment and calcium addition significantly improved the heat-induced gel properties but had a minor effect on protein solubility and dispersion stability at pH 8. Water and protein holding capacities of the gels were the highest for the phytase-treated sample (91 and 97%, respectively), followed by the sample with added calcium (86 and 94%, respectively) and control sample (60 and 86%, respectively). Gel firmness followed the same pattern. Scanning electron microscopy images revealed an interconnected structured network in the phytase-treated gel, while in the control gel, a more rigid and open structure was observed. The improved gelation properties resulting from the phytase treatment suggest that the protein and soluble dietary fibre-enriched rapeseed press cake ingredient serve as a promising raw material for gelled food systems. The positive effect of calcium addition on gel properties proposes that part of the improvement observed after phytase treatment may be caused by cations released from phytate.

Evaluation of the efficacy of a novel phytase in short-term digestibility and long-term egg production studies with laying hens

Three independent trials were conducted to evaluate the efficacy of a novel phytase in laying hens. Trial 1 used a total of 90 laying hens (Lohmann Brown, 33-wk-old) fed either a negative control (NC) diet with 0.09% non-phytate P (NPP) or NC supplemented with 187.5 or 375 FYT phytase/kg feed for 4 d before collection of excreta and ileal digesta to measure ileal digestibility and retention of Ca and P. In trial 2 and 3, a total of 108 laying hens (Hy Line Brown, 25-wk-old) and 360 hens (Lohman Brown, 25-wk-old) were used, respectively. In both trials, the hens were randomly assigned to 3 dietary treatments: NC with 0.1% NPP, positive control (PC) and NC plus 187.5 FYT phytase/kg feed, the experimental diets were fed for 12 wk, and egg production and bone mineralization were measured. The results showed that the ileal digestibility of P increased both linearly (P = 0.012) and quadratically (P = 0.01) with increasing supplementation of phytase in trial 1. In trial 2, phytase supplementation significantly improved egg production, egg weight, and feed conversion ratio and reduced the percentage of broken eggs during the overall trial duration compared with NC. In trial 3, phytase significantly improved egg production, egg weight, and feed intake and reduced the percentage of broken eggs during the entire trial duration. In addition, percentage and weight of bone Ca and P increased significantly with added phytase. In trial 2 and 3, there was no significant difference between PC and the phytase treatment. In conclusion, the novel phytase significantly increased the ileal digestibility of P in a short-term digestibility study and improved egg production and bone mineralization in a 12-wk laying cycle. Ileal digestibility of P rather than P retention in short-term digestibility studies as well as egg production and whole tibia mineralization in long-term studies should be measured to demonstrate the efficacy of phytase in laying hens.

Bioprocessing of Pea Protein can Enhance Fortified Fe But Reduce Zn In Vitro Bioaccessibility.

The bioaccessibility of minerals during food digestion is essential in facilitating absorption and hence mineral bioavailability. Bioprocessing approaches have shown promising effects on Fe and Zn bioaccessibility in plant food matrices. In this study, lactic acid bacteria fermentation or enzymatic hydrolysis was performed on pea protein concentrates (PPCs) to investigate their effects on the bioaccessibility of fortified Fe and Zn salts. Simulated digestion studies revealed that enzymatic hydrolysis was more effective than fermentation. Phytase treatment significantly (P < 0.05) improved Fe3+ bioaccessibility by 5- and 12-fold during fasted and fed digestion stages, respectively. Combined phytase and protease hydrolysis led to a 6- and 15-fold enhancement of Fe3+ bioaccessibility during these stages. None of the bioprocessing approaches led to significant promotive effects on Zn2+ bioaccessibility during fasted or fed digestion. Results of this study show the potential of enzymatic treatment of PPC to significantly promote Fe bioaccessibility.

Improving effect of phytase treatment on the functional properties and in vitro digestibility of protein isolate from Cinnamomum camphora seed kernel

Phytate, an anti-nutritional factor in Cinnamomum camphora seed kernel protein isolate (CPI), chelated with minerals and proteins to form complexes that reduced their bioavailability. The study aimed to evaluate the effects of phytase treatment on the structural and functional properties and in vitro digestibility of CPI. The results showed that the degree of phytate degradation was improved with the increase in phytase treatment time. Most of the original secondary structures were retained in the treated CPI samples. The removal of phytate increased the Zeta potential of CPI, and the protein isoelectric point was increased. Low phytate CPI samples showed higher thermal stability and higher Ca2+ content. In terms of functional properties, foaming capacity was positively correlated with phytate content, whereas foam stability, emulsifying activity index and emulsion stability index were negatively correlated with phytate content. The reduction of phytate content had a positive effect on in vitro gastrointestinal digestion, and the bioavailability of CPI was significantly improved. These results have demonstrated that phytase treatment retained most of the original structure, and improved functional properties and digestibility of the protein isolate from Cinnamomum camphora seed kernel.

Research status of Bacillus phytase.

Phytic acid is abundant in seeds, roots and stems of plants, it acts as an anti-nutrient in food and feed industry, since it affects the absorption of nutrients by humans and monogastric animals. Furthermore, phosphorus produced through its decomposition by microorganisms can cause environmental pollution. Phytase degrades phytic acid generating precursors of inositol that can be used in clinical practice; in addition, phytase treatment can minimize the anti-nutritional effect of phytic acid. The use of phytase synthesized from Bacillus is more advantageous due to its high activity. Additionally, its good heat resistance under neutral conditions greatly fills the gap of commercial utilization of acid phytase. In this review, we summarize the latest research results on Bacillus phytase, including its physiological and biochemical characteristics, molecular structure information, calcium effects on its catalytic activity and stability, its catalytic mechanism and molecular modification.

Phytase Mediated Beneficial Impact on Nutritional Quality of Biofortified Wheat Genotypes

Background: Biofortification has been proposed as an intervention towards alleviation of micronutrient deficiency in the population of developing countries. However, the presence of anti- nutritional factor phytic acid in staple cereals chelates divalent cations and decreases their bioavailability for monogastric animals. Thus, the use of phytase enzyme for hydrolysing phytate-P and enhancing the amount of free divalent cations is of great importance. Methods : In this study, two phytases i.e. APF1 phytase from fungal source and commercial wheat phytase were supplemented with flours of biofortified wheat genotypes and their impact on food quality parameters was accessed. Since commercial wheat phytase is costly, it was used as known phytase to compare the application of APF1 phytase. The phytic acid content was reduced in the range of 70 to 84% with APF1 phytase and 79 to 89% with the wheat phytase as compared to untreated samples, respectively. In contrast to phytate, the dialyzability of important micronutrients Fe and Zn enhanced in the range of 21.9 to 48% and 39.5 to 96% with APF1 phytase and, 6.10 to 30% and 23.2 to 81% with wheat phytase, over untreated samples, respectively. Results and Discussion: A decrease in tannin content was observed in the range of 8 to 23% and 7 to 23% after treatment with APF1 and wheat phytase, respectively. The phytase treatment has resulted in increased soluble protein content and inorganic phosphate content to different level over untreated samples. Conclusion: The study revealed that APF1 phytase was comparatively more effective for enhanced nutritional quality of wheat flour through phytase supplementation for its food based applications.

Dietary betaine reduces plasma homocysteine concentrations and improves bone strength in laying hens

ABSTRACT 1. This study tested the hypothesis that the methyl-donor properties of betaine could reduce homocysteine concentrations, which has been recognised in a previous genetics study to be linked to bone quality. This was combined with phytase treatment, as phosphorus is critical for bone mineralisation. 2. Using a 2 × 2 factorial arrangement, a total of 1920 Lohmann LSL-lite chickens housed as 24 replicates of 20 chickens were fed one of four diets containing dietary betaine (0 or 1000 mg/kg) and phytase (300 or 1000 FTU/kg) from one day old until end-of-lay. Blood and bone samples were collected at 45 and 70 weeks of age. 3. Hens fed betaine had lower plasma homocysteine level (P < 0.05), higher tibia breaking strength (P < 0.05) and higher tibia bone density (P < 0.05). 4. Egg production and quality was excellent throughout the study and were not affected by the dietary treatments. 5. The addition of dietary betaine was successful at reducing plasma homocysteine concentrations and improving bone strength in laying hens, which could be used as an intervention to alleviate welfare concerns.

Impact of Fermentation and Phytase Treatment of Pea-Oat Protein Blend on Physicochemical, Sensory, and Nutritional Properties of Extruded Meat Analogs.

Plant materials that are used for the production of extruded meat analogs are often nutritionally incomplete and also contain antinutrients, thus there is a need to explore alternative plant proteins and pre-treatments. This study demonstrates application of phytase and fermentation to a pea-oat protein blend with a good essential amino acid profile and subsequent texturization using extrusion cooking. Enzymatic treatment reduced the content of antinutrient phytic acid by 32%. Extrusion also degraded phytic acid by up to 18%, but the effect depended on the material. Differences in physicochemical, sensorial, and textural properties between untreated and phytase-treated extruded meat analogs were small. In contrast, fermented material was more difficult to texturize due to degradation of macromolecules; physicochemical and textural properties of extrudates were markedly different; sensory analysis showed enhancement of flavor, but also detected an increase in some unwanted taste attributes (bitterness, cereal and off-taste). Phytic acid was not degraded by fermentation. Analysis of volatile compounds showed extrusion eliminated volatiles from the raw material but introduced Maillard reaction products. Overall, phytase treatment and fermentation demonstrated the potential for application in extruded meat analogs but also highlighted the necessity of optimization of process conditions.

Improvement of chemical properties of noodle and pasta using dephytinized cereal brans

In this research, cereal brans (rice, rye, wheat and oat) were dephytinized by two different methods (phytase enzyme and malt flour) and used in noodle and pasta formulation (20%) to improve nutritional quality of the final product. As a result of phytase treatment, phytic acid content of different bran samples decreased between 70.9 and 83.5%. Rice bran noodles and pasta samples gave the highest amount of phytic acid. In general, the use of cereal bran in noodles samples increased protein and fat content compared to control noodles. The use of cereal bran increased the total dietary fiber content by 1.9–3.3 times in noodle and 1.7–2.9 times in pasta samples. All bran samples increased total phenolic content and antioxidant activity values in noodles and pasta samples (p < 0.05). The amount of Ca, P, K, Mg and Zn of cereal bran noodles and pasta samples was higher than control noodles and pasta samples (p < 0.05). In addition to nutritional enrichment, it was concluded that the noodles and pasta samples with a lower phytic acid content can be produced using dephytinized cereal brans.

Effect of phytase treatment of sorghum flour, an alternative for gluten free foods and bioaccessibility of essential minerals.

This study evaluated the effect of phytase treatment on the bioavailability of iron (Fe), calcium (Ca), zinc (Zn), and myo-inositol phosphate fractions in sorghum flour; and characterized its macronutrients and minerals. The proximate composition and mineral content indicated that, sorghum flour has a nutritional potential superior to wheat and maize. The results obtained in the solubility and dialysis assays indicated that, naturally occurring minerals (without phytase treatment) in sorghum flour, presented considerable bioaccessibility; reaching 32, 47 and 67% of dialyzable Fe, Zn, and Ca respectively. The use of phytase had a positive influence on the reduction of myo-inositol phosphates, mainly the IP6 fraction, present in sorghum flour samples, and an increase in the soluble percentage (Fe 52% for one sample, for Zn higher than 266%) and dialyzed minerals (Fe 7.8-150%; Zn 19.7 for one sample; and Ca 5-205%) for most samples. Therefore, the essential minerals naturally occurring in sorghum have an absorption potential; and the use of phytase reduced the IP6 fraction and improved the availability of the minerals evaluated.

Isolation, Identification, and Characterization of Phytase Producing Probiotic Lactic Acid Bacteria from Neonatal Fecal Samples Having Dephytinization Activity

ABSTRACTPhytic acid, the main phosphate storage component of plant-based diet, is one of the prime causes of micronutrient deficiency in vegetarians due to the formation of non-degradable cation-phytic acid complex in gastrointestinal tract of monogastric animals that are devoid of phytase enzyme. Therefore, the present study was designed to isolate phytase producing probiotic from neonatal feces which may enhance the bioavailability of phosphorous micronutrient. Experimentally, 13 phytase producing lactic acid bacteria (LAB) were isolated from 28 neonatal fecal samples and characterized both phenotypically and for probiotic attributes. Among these, Isolate 5b exhibited potent probiotic potential with significant (p < .01) phytase activity (4.55 U/mL) and was identified phylogenetically using both 16S rRNA and MALDI-TOF MS analysis as Pediococcus acidilactici BNS5B. Interestingly, it was found that phytase from P. acidilactici BNS5B significantly dephytinized phytic acid from modified diet (96.59%) and brown bread (88.89%) after 15 min of phytase treatment at 37°C. Therefore, this provides an opportunity to develop P. acidilactici BNS5B as a probiotic to be used as a supplement in feed/food of monogastric animals and humans. This also provides the rationale for further in vivo studies to use phytase producing probiotic in relation to maintaining and improving health.

Response of Broilers to Dietary Incorporation of Different Sorghum Varieties Fortified with Phytase

Dietary inclusion of local varieties of sorghum in poultry nutrition can greatly lower the cost of production in Sudan. The objective of the study was to evaluate the effect of dietary incorporation of different sorghum varieties fortified with phytase enzyme supplementation on broiler performance. A (2 x 5) factorial arrangement was used in a completely randomized design to study the effect of dietary incorporation of different levels sorghum variety Mogod (0, 25, 50, 75 and 100%) replacing the variety Feterita fortified with two levels of phytase supplementation (0 and 0.05%) on broiler performance. A total of 10 treatments were employed and each treatment was replicated three times with ten birds each. Weight gain (WG), Feed consumption (FC) and feed conversion ratio (FCR) were recorded. Carcass weights and tibial phosphorus content were measured. Blood samples were collected for blood parameters. The results showed that, FC was not affected by dietary inclusion of Mogod and phytase supplementation. There were significant (p≤0.01) effects of Mogod and phytase on weight gain. The greatest weight gain values were recorded with birds fed on diets contained 100% Feterita (p<0.01). Supplementation of phytase improved WG and FCR (p<0.01). The largest carcass weights were reported with birds fed on diets containing 50 and 100% Mogod (p<0.05). Carcass weight values were increased with phytase supplementation. Tibial phosphorus content was improved by phytase supplementation. Total blood protein, cholesterol, calcium and phosphorus were not affected by phytase treatment. The study concluded that Mogod variety could be used as alternative energy source in broiler diets replacing Feterita variety. Moreover, phytase supplementation improved the broiler performance.

Phytase treatment of a protein-enriched rice bran fraction improves heat-induced gelation properties at alkaline conditions

The effect of phytase treatment on the technological functionality of a protein-enriched rice bran fraction produced by air classification was studied. Protein solubility and surface hydrophobicity were analysed and heat-induced gels formed at pH 5, 6.7 and 8 were characterised using rheological measurements, confocal laser scanning microscopy (CLSM) and by measuring water retention capacity. Phytase treatment decreased phytic acid content from 22% to 1–3%, depending on the dispersion dry matter content, which led to improved protein solubility at acidic pH 2–4. Similarly, phytase treatment increased protein surface hydrophobicity; however, the difference between phytase-treated and control sample was diminished after heat treatment. During heat-induced gelation the non-phytase-treated fraction formed viscoelastic structures at pH 6.7 and 8 with final Gʹ over 1000 Pa, while only weak gels were obtained at pH 5 (Gʹ ~100 Pa). Phytase treatment improved gelling ability of the fraction at pH 8 reaching significantly higher final Gʹ (11 340 Pa) and water holding capacity (77.8%) compared to the non-phytase-treated gel (1140 Pa and 54.6%, respectively). At pH 5 and 6.7 gel characteristics were not affected by phytase treatment. CLSM revealed a more evenly distributed protein and fibre network for phytase-treated protein-enriched rice bran gels formed at pH 8 compared to the other gels, which consisted of more void areas and densely packed protein aggregates. The results emphasise the advantage of using a phytase-treated protein-fibre ingredient from rice bran in gelled products both for techno-functional and nutritional quality improvement.

Characteristics of an Acidic Phytase from Aspergillus aculeatus APF1 for Dephytinization of Biofortified Wheat Genotypes.

Phytases are the special class of enzymes which have excellent application potential for enhancing the quality of food by decreasing its inherent anti-nutrient components. In current study, a protease-resistant, acidic phytase from Aspergillus aculeatus APF1 was partially purified by ammonium sulfate fractionation followed by chromatography techniques. The molecular weight of partially purified phytase was in range of 25-35kDa. The purified APF1 phytase was biochemically characterized and found catalytically active at pH3.0 and 50°C. The Km and Vmax values of APF1 phytase for calcium phytate were 3.21mM and 3.78U/mg protein, respectively. Variable activity was observed with metal ions and among inhibitors, chaotropic agents and organic solvents; phenyl glyoxal, potassium iodide, and butanol inhibited enzyme activity, respectively, while the enzyme activity was not majorly influenced by EDTA, urea, ethanol, and hexane. APF1 phytase treatment was found effective in dephytinization of flour biofortified wheat genotypes. Maximum decrease in phytic acid content was noticed in genotype MB-16-1-4 (89.98%) followed by PRH3-30-3 (82.32%) and PRH3-43-1 (81.47%). Overall, the study revealed that phytase from Aspergillus aculeatus APF1 could be effectively used in food and feed processing industry for enhancing nutritional value of food.

Use of Plackett–Burman design for enhanced phytase production by Williopsis saturnus NCIM 3298 for applications in animal feed and ethanol production

Distiller-dried grain solid (DDGS), a co-product of alcohol production, contains cereal grain residues, proteins, and yeast metabolites, which make it suitable in poultry feeding. However, high phytate content of DDGS limits its applicability in poultry feed. In this study, Plackett-Burman design was used to improve cell-bound phytase production by Williopsis saturnus NCIM 3298, and we achieved an enzyme activity of 269IU/g of dry-wet biomass. The effect of this enhanced phytase-displaying yeast strain on hydrolysis of corn phytate and subsequently on ethanol production and DDGS quality was then investigated. Results of saccharification in the presence of phytase showed that reducing sugar content of liquefied mash increased by 11%, which subsequently improved the ethanol production by 18% (w/v) (p < 0.01) compared with the control. Notably, phytase treatment decreased the phytate content of corn by 70% (p < 0.01) compared with the control, thereby improving the availability of free phosphate in fermentation broth and DDGS. Thus, the results obtained suggest that the addition of W. saturnus NCIM 3298 strain has the potential of providing a new source of phytase that would be useful in the feed and ethanol industries.

Compositional and processing effects in promoting the bioaccessibility of iron and zinc of ready to cook high protein kheer mix

Iron and zinc deficiencies are the major micronutrient deficiencies of public health resulting from poor bioavailability due to the presence of phytic acid from plant foods. The investigation was undertaken to formulate a high protein kheer mix using different legumes and processing by different modes of thermal and enzymatic treatment and identify the one with maximum bioaccessibility of minerals. Semolina based kheer mixes with different decorticated split legumes (dhal) were formulated by adopting different modes of thermal treatment such as dry and moist heat. Phytase treatment was tested in one of the processing methods. The ready to cook kheer mix formulation with different legumes contained 20–34% protein, 3.4–11.7 mg iron and 2.1–3.0 mg zinc per 100 g. Bioaccessibility of minerals was negligible due to high phytic acid content. A strong negative correlation existed between the iron bioaccessibility and phytic acid in raw and processed mixes. Among the treatments adopted, a combination of enzymatic and moist heat treatment was found to be effective in promoting the bioaccessibility of minerals. The enhancement noticed in bioaccessible iron was 2.0–2.6 fold and 2.0–4.0 fold for zinc in reconstituted kheer with good organoleptic scores. Further trials with fortification of minerals are warranted.