In Vitro Digestibility Research Articles

Pomegranate seed as a novel source of plant protein: Optimization of protein extraction and evaluation of invitro digestibility, functional, and thermal properties.

This research was carried out to optimize the extraction process of proteins from pomegranate seeds and characterize their invitro digestibility as well as their thermal and functional properties. For this purpose, the study screened five parameters (liquid/solid ratio, pH, temperature, NaCl concentration, and time) that could potentially influence the extraction process. This screening was conducted using a two-level Placket-Burman design (PBD). The significant parameters (pH and NaCl concentration) were subsequently optimized using a three-level face-centered central composite design (FCCD) to determine the optimum extraction conditions. A maximum protein recovery of 83.8% was obtained at pH 11.0 and NaCl concentration of 0.0 M. Pomegranate seed protein isolate (PSPI) with a protein content of 92.4% (w/w) was obtained through the isoelectric precipitation of pomegranate seed protein extracted under the optimized conditions. An emulsifying activity index of 14.1 m2 g-1 was observed at the isoelectric pH, where the emulsion stability index was at 8.2%. PSPI also showed high water- and oil-holding capacities (3.7 and 4.3 g g-1, respectively). The essential amino acid levels in PSPI (except for valine and isoleucine) exceeded the recommended amounts set by WHO/FAO/UNU for adults, highlighting its high nutritional value. Based on thermal analysis data, denaturation of PSPI could occur at 89.5°C. The invitro digestibility of PSPI was found to be 74.3%. PSPI shows a potential as a novel ingredient for substituting animal-based proteins in various food applications.

Genome-wide association study for in vitro digestibility and related traits in triticale forage

BackgroundTriticale is making its way on dairy farms as an alternative forage crop. This requires the availability of high-yielding triticale varieties with good digestibility. Triticale forage breeding mainly focussed on biomass yield, but efforts to improve digestibility are increasing. We previously investigated the interrelationships among different quality traits in soft dough triticale: starch, acid detergent fibre and in vitro digestibility of organic matter (IVOMD) and of neutral detergent fibre (IVNDFD) of the total plant, IVNDFD and Klason lignin of the stems, and ear proportion and stem length. Here we determine the genetic control of these traits, using a genome-wide association (GWAS) approach. A total of 33,231 DArTseq SNP markers assessed in a collection of 118 winter triticale genotypes, including 101 varieties and 17 breeding lines, were used.ResultsThe GWAS identified a total of 53 significant marker-trait associations (MTAs). The highest number of significantly associated SNP markers (n = 10) was identified for total plant IVNDFD. A SNP marker on chromosome 1A (4211801_19_C/T; 474,437,796 bp) was found to be significantly associated with ear proportion, and plant and stem IVNDFD, with the largest phenotypic variation for ear proportion (R²p = 0.23). Based on MTAs, candidate genes were identified which were of particular relevance for variation in in vitro digestibility (IVD) because they are putatively involved in plasma membrane transport, cytoskeleton organisation, carbohydrate metabolic processes, protein phosphorylation, and sterol and cell wall biogenesis. Interestingly, a xyloglucan-related candidate gene on chromosome 2R, SECCE2Rv1G0126340, was located in close proximity of a SNP significantly associated with stem IVNDFD. Furthermore, quantitative trait loci previously reported in wheat co-localized with significantly associated SNP markers in triticale.ConclusionsA collection of 118 winter triticale genotypes combined with DArTseq SNP markers served as a source for identifying 53 MTAs and several candidate genes for forage IVD and related traits through a GWAS approach. Taken together, the results of this study demonstrate that the genetic diversity available in this collection can be further exploited for research and breeding purposes to improve the IVD of triticale forage.

76 An in-vitro analysis of hemp as feed for beef cattle

Abstract Hemp, Cannabis sativa L., is a versatile crop that has been cultivated for centuries. Cannabis production had been outlawed in the United States due to concerns related to tetrahydrocannabinol (THC) intoxication. However, recent legislation has declassified hemp as a schedule 1 drug under regulated conditions (i.e., THC < 0.3%). Thus, hemp has been reclassified as an agricultural commodity, and its production for fiber, food, and medicine has increased. Hemp cultivation results in by-products that are not utilized for human needs and have potential as livestock feed, especially for ruminants. Current regulations restrict the use of hemp and its by-products in livestock systems due to the presence of cannabinoids. Thus, research on the nutritional value of hemp for cattle is lacking. The objective of this study was to characterize the nutrient concentrations, in-vitro digestibility (IVD), and cannabinoid concentrations of different fractions of the hemp plant. Procedures involving animals were approved by IACUC at Texas State University (#8497). Four replications of hemp plants of the Cherry Soda varietal were cultivated at Texas State University. Samples were air-dried and fractionated into lower (n = 4), leaves (n = 4), stalks (n = 4), and whole plant (n = 4). Dry matter, organic matter (OM), acid detergent fiber (ADF), neutral detergent fiber (NDF), and crude protein (CP) were determined. For IVD, samples were incubated in digestion vessels containing buffers and rumen fluid at 39.5°C for 48 h and subsequently analyzed for NDF. Cannabinoid analysis was conducted via high-performance liquid chromatography (HPLC). The OM was in acceptable ranges for each hemp fraction (69-95%). The NDF and ADF were within normal ranges of conventional livestock feeds and forages for most fractions, except hemp stalk (81% NDF, 69% ADF). There was high variability in CP between fractions, with the least concentrations observed in the stalk (4%) and greatest in the flower (25%). Stalks had an IVD of 21%, whole plant of 67%, flower of 87%, and leaves of 93%. Cannabinoids were present in each fraction and especially concentrated in the flower (14%) and depleted in the stalk (0.06%). Flower had THC of 0.56%, while other fractions were less than the 0.3% legal threshold. Similarly, total cannabidiol (CBD) ranged from 0.05-11.4% with the greatest concentrations in the flower and least in the stalk. Our results indicate there is potential for hemp to be integrated into cattle production, especially the leaves. Despite adequate nutritional value, there are practical limitations with feeding hemp flower to cattle. In-vivo trials are needed to assess digestibility and profile cannabinoid metabolism in various tissues before hemp can be integrated into cattle diets.

Investigating the effect of natural fermentation in modifying the physico-functional, structural and thermal characteristics of pearl and finger millet starch.

In recent years, millets are often considered an emerging crop for sustainable agriculture. Therefore, millets can be exploited as an alternative source of starch which has many applications ranging from food, packaging, bioplastics, and others. However, starch is seldom used in its native form and is more often modified to enhance its functional properties. In literature, many traditional millet-based food recipes often incorporate a fermentation step before cooking. Therefore, using this traditional knowledge fermentation has been explored as a potential method for modifying millet starch. Pearl millet (PM) and finger millet (FM) flour were allowed to naturally ferment for 24 h followed by starch extraction. Compared to native (N) starch,water/oil holding capacity and least gelation concentration of fermented (F) starch decreased with no significant change in swelling power. The solubility, paste clarity and in vitro digestibility of starch were significantly affected by fermentation. X-ray diffraction (XRD) data indicates that after fermentation, crystallinity increased while the A-type crystalline structure remained intact. Fourier-transform infrared (FTIR) spectra showed no deletion or addition of any new functional groups. Thermal characterization by differential scanning calorimetry (DSC) showed that the enthalpy of gelatinization of PM starch decreased while that of FM starch increased after fermentation. The results indicate that 24 h natural fermentation had a significant impact on functional properties of starch without altering the structural architecture of starch granules. Therefore, fermentation can be further explored as a low-cost alternative for starch modification. © 2023 Society of Chemical Industry.

Development of curcumin-loaded nanoemulsion stabilized with texturized whey protein concentrate: Characterization, stability and invitro digestibility.

The impacts of pH (2.8, 4.5, and 7.2) and extrusion cooking temperature (60°C, 85°C, and 110°C) on properties of native whey protein concentrate (NWPC) were evaluated, followed by delivering of curcumin through a nanoemulsion system stabilized with extruded WPC (EWPC). Protein solubility, surface hydrophobicity, and emulsion properties such as emulsion activity index (at 1% [w/w] protein concentration), stability index (at 0.5%, 1%, 2%, and 4% [w/w] protein concentration) and creaming index (evaluated at different protein concentrations [0.5%, 1%, 2%, and 4% w/w] and oil levels [20%, 40%, 60%, and 80%]) were improved as a function of the extrusion process. It was found that both covalent and non-covalent interactions contributed to the stabilization of the extrudates. The rheological investigation of the emulsions stabilized with EWPC (at different oil levels [20%, 40%, 60%, and 80%]) revealed high viscosity and shear thinning behavior as well as much higher G' and G″ values. Encapsulation efficiency was increased from 90.8% to 95.7% when NWPC and EWPC were used, respectively. The curcumin-loaded nanoemulsion containing EWPC presented high stability in confronting with ionic strength (NaCl salt with a concentration of 0.1-1 M), pH (3, 5, and 7), thermal treatments (pasteurization at 63°C for 30 min and sterilization at 95°C for 10 min) and storage time (1 month at 4°C and 25°C). Invitro release behavior revealed that samples stabilized with EWPC showed burst release in simulated intestine conditions. However, it was more stable in stomach conditions.

Nutritive value and in-vitro digestibility of peels and pomaces of different citrus species

The nutritive value and invitro digestibility of agro-industrial byproducts of Citrus aurantium, Citrus paradisi, Citrus reticulata, Citrus limon and Citrus sinensis were assessed for their feed modification potential. Nutritive value assessment was done through chemical analysis while the ANKOM Daisy II incubator method was used to determine the invitro digestibility. At p>0.05, there was no statistical significance for nutritive value of the citrus byproducts for the five species. The agro-industrial by-products had significantly different phenolic content. Invitro digestibility of the peels significantly differed from the pomaces (p<0.001). The byproducts of the five citrus species showed potential to be considered as non-forage energy sources in ruminant feed. Lemon byproducts had high protein but not sufficient as a single protein source while bitter orange pomace may be considered for antioxidant capacity and high digestibility. Abundance of citrus agro-industrial byproducts, nutritive value potentials and their digestibility makes it a good strategy for ruminant feed modification and utilization.

Forage calibration transfer from laboratory to portable near infrared spectrometers

Portable near infrared (NIR) spectrometers are now readily available on the market and with their smaller size, weight and cost have provided the opportunity to analyze forages both on farms and directly in the field. As new technologies and new portable NIR instruments become available on the market, calibrations for these instruments become a major constraint due to the costs and time necessary to collect reference data. This study evaluated techniques to transfer calibrations for alfalfa and grass forage samples that were developed for a scanning benchtop monochromator (FOSS 6500, 400–2498 nm, LAB) to a diode array instrument (AuroraNir, 950–1650 nm, DA), a digital light processing instrument (NIR-S-G1, 950–1650 nm, DLP) and a short wavelength instrument (SCiO, 740–1070 nm, SCIO). Alfalfa (N = 612) and grass (N = 516) samples from eight agronomic studies were analyzed by wet chemistry for crude protein, neutral detergent fiber (NDF), acid detergent fiber (ADF), in-vitro digestibility (IVTD) and NDF digestibility (NDFD) and divided into calibration, test-set, standardization and inoculation/prediction datasets. Different calibration transfer strategies were evaluated: Spectral Bias Correction (SBC), Shenk and Westerhaus algorithm (SW), Piecewise Direct Standardization (PDS), Dynamic Orthogonal Projection (DOP) or creating a new calibration using LAB predictions of the inoculation/prediction dataset as reference values. All computations for trimming, calibration, validation and standardization were developed using R. SBC with inoculation was an effective method to transfer calibrations for DA. Validation errors for DA transferred calibrations were about 15% lower than LAB for alfalfa data but 6% greater for grass data. For SCIO after DOP spectral adjustment, predicting errors were slightly greater than LAB for both data sets, while prediction errors with DLP were two to three times greater than LAB even after inoculation. PDS created spectral artifacts in the spectra of all three portables, which then resulted in large validation errors. Using LAB predictions as reference values was suitable only for DA, while DLP and DA had large prediction errors. This study showed that calibration sharing between a benchtop and portable instruments is challenging, but possible depending on the portable technologies and the transfer method. Spectral bias correction plus inoculation was the best method to transfer multivariate models for the forage components’ prediction from LAB to handhelds, particularly for DA. Application of DOP was beneficial for SCIO to successfully maintain performance of the original calibration, while for DLP the prediction models were not accurate. Additional studies are necessary to verify these transferring techniques can also be applied to fresh forages, allowing an easier and extended implementation of NIR analysis directly in fields.

Practical Considerations for Using the NeoSpectra-Scanner Handheld Near-Infrared Reflectance Spectrometer to Predict the Nutritive Value of Undried Ensiled Forage.

Prediction models of different types of forage were developed using a dataset of near-infrared reflectance spectra collected by three handheld NeoSpectra-Scanners and laboratory reference values for neutral detergent fiber (NDF), in vitro digestibility (IVTD), neutral detergent fiber digestibility (NDFD), acid detergent fiber (ADF), acid detergent lignin (ADL), crude protein (CP), Ash, and moisture content (MO) from a total of 555 undried ensiled corn, grass, and alfalfa samples. Data analyses and results of models developed in this study indicated that the scanning method significantly impacted the accuracy of the prediction of forage constituents, and using the NEO instrument with the sliding method improved calibration model performance (p < 0.05) for nearly all constituents. In general, poorer-performing models were more impacted by instrument-to-instrument variability. The exception, however, was moisture content (p = 0.02), where the validation set with an independent instrument resulted in an RMSEP of 2.39 compared to 1.44 where the same instruments were used for both calibration and validation. Validation model performance for NDF, IVTD, NDFD, ADL, ADF, Ash, CP, and moisture content were 4.18, 3.86, 6.14, 1.10, 2.75, 1.42, 2.71, and 1.67 for alfalfa-grass silage samples and 3.22, 2.21, 4.55, 0.38, 2.07, 0.50, 0.51, and 1.62 for corn silage, respectively. Based on the results of this study, the handheld spectrometer would be useful for predicting moisture content in undried and unground alfalfa-grass (R2 = 0.97) and corn (R2 = 0.93) forage samples.

Chestnut extracts decrease the in-vitro digestibility and polyphenol bioavailability of soy-based nutrients but protect the epithelial barrier function of pig jejunum segments after digestion

Polyphenols are known to interact with protein fractions of feed ingredients in the digestive tract thereby affecting the digestibility. These effects may differ depending on the chemical composition of the protein fractions. Thus, the objective of the study was to study the impact of a tannin-rich chestnut extract (CHE) on the in-vitro digestibility (IVD) of soy protein isolate (SPI), screw-pressed soybean (SPS) and solvent-extracted soybean (SES).In addition, CHE-derived metabolites were tested for their effects on intestinal epithelial integrity. The SPI, SPS, and SES were digested in vitro without (SPI-, SPS-, SES-) or with CHE (SPI+, SPS+, SES+) or as a control (C) solely CHE. The metabolites and the polyphenols content after digestion of the soy-based products with or without CHE were quantified. The trans-epithelial resistance (TEER) was monitored in porcine jejuna in the presence of CHE-derived metabolites at three dilutions (1:4, 1:8, and 1:16 v/v) or in their absence. The claudin-1 (CLDN1), occludin (OCLN) and zonula occludens-1 (ZO1) tight junctions-protein expressions were determined. Finally, the effects of CHE-metabolites against indomethacin (INDO)-induced decrease of TEER were tested ex vivo. The CHE decreased the IVD (P < 0.05) and decreased the detectable polyphenol content (P < 0.05) after digestion of CHE with SPI, SPS, or SES. The SPI and SPI+CHE were the samples with the highest content of metabolites generated after the digestion, while CHE presented the lowest content of metabolites. No detrimental effects on TEER were observed. The 1:8 dilution increased (P < 0.05) both ZO1 and OCLN protein expression by up to + 60% compared to the control, while the dilution 1:16 increased ZO1 expression by + 100% without affecting OCLN expression. The 1:16 dilution also protected the jejunum from the effects induced by INDO. These results suggest that the anti-nutritional effects exerted by CHE on soy-based meals IVD may depend on the meal’s chemical composition. Moreover, we showed that CHE polyphenols exert protective effects on the intestinal epithelium integrity ex vivo at low concentrations.

The Relative Performance of a Benchtop Scanning Monochromator and Handheld Fourier Transform Near-Infrared Reflectance Spectrometer in Predicting Forage Nutritive Value

Advanced manufacturing techniques have enabled low-cost, on-chip spectrometers. Little research exists, however, on their performance relative to the state of technology systems. The present study compares the utility of a benchtop FOSS NIRSystems 6500 (FOSS) to a handheld NeoSpectra-Scanner (NEO) to develop models that predict the composition of dried and ground grass, and alfalfa forages. Mixed-species prediction models were developed for several forage constituents, and performance was assessed using an independent dataset. Prediction models developed with spectra from the FOSS instrument had a standard error of prediction (SEP, % DM) of 1.4, 1.8, 3.3, 1.0, 0.42, and 1.3, for neutral detergent fiber (NDF), true in vitro digestibility (IVTD), neutral detergent fiber digestibility (NDFD), acid detergent fiber (ADF), acid detergent lignin (ADL), and crude protein (CP), respectively. The R2P for these models ranged from 0.90 to 0.97. Models developed with the NEO resulted in an average increase in SEP of 0.14 and an average decrease in R2P of 0.002.

The Substitution of Corn Silage with Potato Pulp Silage at Differing Level in Dairy Cows on Milk Yield, Composition and Rumen Volatile Fatty Acids*

The aim of this study was to determine the quality of potato pulp silage (PPS) prepared with wheat bran and barley straw and the effects of the substituting corn silage with potato pulp silage at differing levels in dairy cows on milk yield, composition and rumen volatile fatty acid (VFA). The study consisted of two experiments. Nutrient con-tents, fermentation parameters, in situ organic matter (OM) and starch degradabilities, in vitro digestibility (IVD) and metabolic energy (ME) content of PPS were determined in the first experiment. The effects of substituting corn silage with potato pulp silage at 0%, 15%, 30% and 45% in the diet of lactating 12 dairy cows on feed intake, milk yield, milk components, rumen fermentation parameters were evaluated in the second experiment. While dry matter (DM), OM and crude protein (CP) contents, pH of silages were statistically similar, starch content, in vitro organic matter digesti-bility (IVOMD), ME, net energy lactation (NEL), and lactic acid values were significantly higher in PPS compared with corn silage (P&amp;lt;0.05). Organic matter intake, milk yield, the composition of milk, post-feeding pH and total VFA levels of ruminal fluid at all sampling hours were similar among the dairy cows (P&amp;gt;0.05). It was concluded that; PPS prepared with wheat bran and straw had a very good silage quality and were even better than corn silage (control). Substitution of corn silage with PPS up to 45% did not cause any negative effects on rumen fermentation parameters and can be safely substituted with corn silage up to 45% in dairy cow diets.

In-Vitro protein digestibility, physico-chemical properties and nutritional quality of sorghum-green gram cookies supplemented with mango powder

Ready to Eat (RTE) sorghum cookies were prepared by incorporating green gram flour at 10%, 20%, 30%, dried mango powder at 10% and evaluated for their physico-chemical and nutritional properties. Protein, fat, fiber and ash increased with increase in green gram flour substitution as carbohydrate content decreased significantly. Significant differences (p ≤ 0.05) in protein content were seen in cookies ranging from 9.52% to 13.60%. Fiber increased significantly from 9.40% to 10.90%. In vitro protein digestibility ranged from 67.75 ± 0.01% to 90.05 ± 0.10 %. Vitamins analysed increased with addition of green gram flour. Thiamine content ranged from 0.22±0.02 to 0.61±0.02 mg/100g, riboflavin from 0.09±0.00 to 1.39±0.04 mg/100g and ascorbic acid from 13.87±0.79 to 19.31±0.94 mg/100g. Value addition of under-utilized crops like sorghum and green grams can play a vital role in development of high nutritional quality RTE products.

Investigating the Quality of Commercial Beef Cattle Feeds and Feed Ingredients Used in Bangladesh

The study was undertaken to evaluate the quality of commercial beef cattle feed and feed ingredients which are available in Bangladesh. For this purpose, chemical analysis and in vitro digestibility (IVD) were estimated for nine commercial feeds and different feed ingredients which were collected from different regions. Chemical analysis of samples was carried out in triplicate for dry matter (DM), crude protein (CP), crude fiber (CF), ether extract (EE), ash, acid detergent fiber (ADF) and neutral detergent fiber (NDF) content. Metabolizable energy (ME) was calculated mathematically for feed samples by using standard formula. The analysis revealed the difference between the manufacturer’s claim and actual analyzed value. In commercial feeds DM content ranged from 90-92%. While CP content of commercial feeds was either lower or higher than the written value of feed industries. In Provita feed CP content (20.72%) was higher and Care feed had much lower CP content (7.54%) than written value. In vitro digestibility of DM in feed ingredients varied from 18.27 in straw to 75.77% in soybean meal. The fiber component (NDF and ADF) was negatively correlated with IVDMD and CP was positively correlated with IVDMD because fiber rich components were less digestible than the non-fibrous component (protein). Analysis of commercial feed samples revealed that the values claimed by the manufacturers are quite different from the actual analyzed values. This is a matter of concern and needs to be checked through better quality control measures by systematic feed analysis and ensure that manufacturers declare the true composition of the marketed feeds.&#x0D; SAARC J. Agri., 18(1): 197-208 (2020)

Efecto del tiempo de fermentación sobre la calidad nutricional del ensilaje de pulpa de Coffea arabica L.

La pulpa de café ha sido incorporada en los sistemas de producción pecuarios a través de su uso en silos dada su aceptable composición nutricional. La presente investigación se desarrolló en la finca La Gaviota, localizada en la vereda Matajira del municipio de Pamplonita (Colombia), con el objetivo de evaluar el efecto que tiene el tiempo de fermentación sobre la calidad nutricional del ensilaje de pulpa de café. Se emplearon tres tratamientos: 30, 45 y 90 días de fermentación y cuatro réplicas de 20 kg. Se aplicaron pruebas de estadística descriptiva, Anova de un factor con tres niveles y una significancia del 5 % bajo un diseño aleatorizado. Los parámetros de pH, fósforo (P) y polifenoles presentaron un comportamiento similar (p &gt; 0,05) respecto al tiempo de fermentación, mientras que los valores de proteína, fibra detergente neutro (FDN), digestibilidad in vitro (DIV) y energía metabolizable (EM) —con medias de 13,50 %, 49,85 %, 57,20 % y 4,50 Mcal/kg MS, respectivamente— presentaron los mejores tenores en el T2 con un tiempo de fermentación de 45 días. Los valores de fibra detergente ácido (FDA) y calcio (Ca) fueron superiores en el T4 con 90 días de fermentación. Se concluye que el tiempo de fermentación tiene influencia sobre los parámetros nutricionales del ensilaje de pulpa de café.

Effect of Dried Rumen Content and Carbohydrate Sources in Ensiling Process on Corn Stover Silage (Zea mays) to Increasing Nutrient Contents and InVitro Digestibility

Effect of Dried Rumen Content and Carbohydrate Sources in Ensiling Process on Corn Stover Silage (Zea mays) to Increasing Nutrient Contents and InVitro Digestibility

Physical, chemical and in vitro digestibility quality of oil palm midrib fermented by Phanerochaete chrysosporium

Oil palm midrib has potential to be used as ruminant feed, but fermented treatment is needed to increase their nutritional value. The study consisted of 2 phases of research. The first phase aims to find out the effect of oil palm midrib fermented by Phanerochaete chrysosporium on the physical and chemical qualities of feed, while the second phase to find out the effect on invitro digestibility. The design of the first stage used the factorial completely randomized design. On the second phase the design used the completely randomized design. The first phase showed significant effect (P <0.05) on the physical and chemical quality. The best of incubation time was 15 days and the best dose was 106 CFU/g. The second phase showed significant effect (P <0.05) on the digestibility of dry matter and organic matter. The best result of second phase is P3 treatment that used Phanerochaete chrysosporium + Saccharomyces cerevisiae in fermentation. It is concluded the use of Phanerochaete chrysosporium + Saccharomyces cerevisiae in fermentation can improve physical and chemical properties and increase the digestibility of oil palm midrib.

IN-VITRO DIGESTIBILITY, VOLLATYLE FATTY ACID, AND AMMONIA OF CORN STRAW SILAGE WITH DIFFERENT STORAGE PERIODE

The study aimed to determine invitro digestibility, volattyle fatty acid (VFA) and ammonia (NH3) of corn straw silage with different storage periode. The experiments use a completely randomized design (CRD) with four treatments and each treatment was repeated five times, so there are 20 experimental units. The fourth treatments are W1 = storage time of 14 days, W2 = storage time of 21 days, W3 = storage time of 28 days, and W4 = storage time of 35 days. The parameters observed in this study in-vitro digestibility including dry matter and organic matter digestibility, VFA, and NH3. Results of the experiment showed that dry matter digestibility showed significant differences, otherwise organic matter digestibility, VFA, and NH3 were not significantly different, and there was a tendency to decrease the value of dry matter and organic matter digestibility, VFA, and NH3 with longer duration of storage of corn straw silage. It can be concluded that dry matter, organic matter digestibility VFA, and NH3, are not significant different.&#x0D; Keywords: corn straw, silage, storage periode, invitro digestibility, VFA, NH3

Effect of Adding Peppermint Oil in Total Gas, Methane Production Gas and Invitro Digestibility

Effect of Adding Peppermint Oil in Total Gas, Methane Production Gas and Invitro Digestibility

Influence of stewing time on the texture, ultrastructure and invitro digestibility of meat from the yellow-feathered chicken breed.

This study assessed the influence of stewing (1, 2 or 3h) on the texture, ultrastructure and invitro digestibility of meat from the yellow-feathered chicken, which is a popular broiler chicken in Asia. Results indicated that longer stewing considerably increased cooking loss of the chicken carcass and tenderness of thigh meat. After 3h of stewing, protein digestibility decreased from 90.5% to 80.3% and fiber diameter decreased by 8.63μm. The shear force value of breast meat decreased from 32.34N at 1h to 10.29N at 2h, and then increased to 39.98N at 3h. The texture profile of breast meat remarkably decreased during stewing. Moreover, increased stewing time induced longitudinal and transversal shrinkage of muscle fibers and the degradation of the myosin heavy chain. These findings suggested that prolonged stewing (3h) resulted in decreased meat qualities, based on the changes in cooking loss, digestibility and texture profile, but that stewing for 2h increased thigh and breast tenderness. Producers could utilize this information to stew yellow-feathered chicken meat with desirable qualities.

Optimization and physicochemical properties of nutritional protein isolate from pork liver with ultrasound‐assisted alkaline extraction

The aim of this study was to investigate the optimal conditions of ultrasound-assisted alkaline extraction (UAAE) on pork liver protein isolate (UPLPI) and its physico-chemical properties. Response surface methodology was used to determine the optimal conditions for UAAE, which were at ultrasonic power 265W, ultrasonic time 42min, NaOH concentration 0.80%, temperature 50°C, and solvent/raw material ratio 70. The extraction yield and efficiency of UPLPI were significantly improved over the conventional alkaline extraction (PLPI). The results of amino acid composition showed that UAAE could increase serine (36.5g/kg), arginine (38.1g/kg), alanine (37.5g/kg), proline (48.7g/kg), phenylalanine (55.6g/kg) and lysine (47.2g/kg) elution amount. The changes in fourier transform infrared spectra indicated unfolding and destruction of the protein structure in UPLPI. The differential scanning calorimetry analysis presented UPLPI with a slightly lower onset and peak denaturation temperature over PLPI. Surface hydrophobicity increased and the microstructures presented larger and more pores of UPLPI, therefore, it had better invitro digestibility than PLPI. Therefore, UPLPI might have a potential application prospect in the food field due to its changes on molecular structure as well as on the microstructure of protein by UAAE.