Cryogelation phenomena in mixed skim milk powder – barley β-glucan–polyol aqueous dispersions

The effects of polyols (fructose, glucose, sorbitol, sucrose and xylose) on cryostructurization of barley mixed-linkage (1 → 3), (1 → 4) β-d-glucans (β-glucans) in the presence of skim milk proteins were investigated; three β-glucan isolates differing in molecular size (apparent molecular weight of 210, 140 and 70 × 10³ Da) were used. Polyols were incorporated at 15% (w/w) concentration into aqueous β-glucan (3% w/w)–skim milk (12% w/w) dispersions and the mixed dispersions were subjected to 14 repeated freezing (−15 °C for 24 h) and thawing (5 °C for 24 h) cycles; all preparations gave compact, opaque gels. For the high molecular weight (210 × 10³) preparation, with exception of sorbitol, the addition of polyols to β-glucan-skim milk dispersions retarded the cryostructurization, as shown by phenomenological observations after each freezing–thawing cycle and resulted in weaker cryostructurates compared to those of control (polyol-free gels), as determined by small deformation mechanical measurements. Xylose and fructose showed a stronger inhibitory effect on structure formation compared to sucrose and glucose, whereas sorbitol appeared as a network promoting co-solute. However, the above effects of polyols were largely diminished with decreasing of the β-glucan molecular weight and seemed to be independent on the type of polyol for the 140 and 70 × 10³ β-glucan samples. Despite the fact that molecular weight of β-glucans can have an impact on the effect of individual polyol on thermostability of cryogels, generally it seems that the melting temperature (T_m) of β-glucan-skim milk cryostructurates, as determined by dynamic rheometry, followed the order sorbitol > sucrose > control, glucose > fructose > xylose. On the other hand, large deformation mechanical tests (compression mode) revealed an increase in firmness and a decrease in brittleness of β-glucan–skim milk cryogels with inclusion of polyols in the order of: sorbitol < sucrose, xylose < fructose, glucose.     

Rheological characterization of acylated and dextran conjugated African yam bean (Sphenostylis stenocarpa Hochst. Ex A. Rich.) proteins

The molecular weight distribution and rheological properties of acetylated, succinylated and dextran conjugated African yam bean (Sphenostylis stenocarpa) proteins dispersion were studied. Succinylation of the protein showed the three prominent electrophoretic bands of the unmodified protein but all the bands disappeared with acetylation. Immobile band characterized dextran conjugated S. stenocarpa electrophoregram. The flow behavior indices (n) of these modified S. stenocarpa protein dispersions were in the range 0.03–0.22. This is an indication that they were pseudoplastic in nature. This pseudoplastic nature was maintained in ionic media 0.05–0.5 mol dm^?3, pH 3–8 and temperature range of 27–75 °C. The yield stresses were 0.270, 0.302 and 0.320 Pa for acetylated, succinylated and dextran conjugated protein respectively. Activation energy of acetylated and succinylated protein were in the range 6.2–8.2 and 2–5.4 J mol^?1 respectively. Thus acetylation of S. stenocarpa protein made its dispersion viscosity more susceptible to temperature change than succinylation. These results suggest that acylation and dextran conjugation of African yam bean (S. stenocarpa) protein produce protein species with different rheological properties.     

Adsorption kinetics,thermodynamics and isotherm of Hg(II) from aqueous solutions using buckwheat hulls from Jiaodong of China

The adsorption kinetics and adsorption isotherms of buckwheat hulls in the region of Jiaodong, China (BHJC) for Hg(II) were investigated. Results revealed that the adsorption kinetics of BHJC for Hg(II) were well described by a pseudo second-order reaction model, and the adsorption thermodynamic parameters ΔG, ΔH and ΔS were –5.83 kJ mol^?1(35 °C), 73.1, and 256 J K^?1 mol^?1, respectively. Moreover, Langmuir, Freundlich and Redlich–Peterson isotherm models were applied to analyse the experimental data and to predict the relevant isotherm parameters. The best interpretation for the experimental data was given by the Langmuir isotherm equation, and the maximum adsorption capacity for Hg(II) is 243.90 mg/g at 35 °C. Furthermore, investigation of the adsorption selectivity showed that BHJC displayed strong affinity for mercury in the aqueous solutions and exhibited 100% selectivity for mercury in the presence of Zn(II) and Cd(II).     

Thermal and light stabilities and antioxidant activity of carotenoids from tomatoes extracted using an ultrasound-assisted completely solvent-free method

The use of petroleum-derived solvents, particularly volatile organic compounds (VOCs), in the chemical industry has increased the contamination and residual effects of these solvents. Ionic liquids (ILs) can potentially replace VOCs, thereby reducing the risks of environmental contamination and toxicity. In this context, the objectives of this study were as follows: 1 — to obtain an ionic liquid for use in extracting carotenoids from tomatoes with ultrasound assistance; and 2 — to determine the stability and antioxidant activity of tomato carotenoid extracts. Ultrasound can also efficiently extract carotenoid compounds with ionic liquids in comparison with conventional VOC solvents (obtained from an all-trans-lycopene 7.5–8.0 μg·g^− 1 tomato sample by IL and 6.2–7.7 μg·g^− 1 by acetone). Similarly, the activation energies (E_a) in aqueous medium were obtained for the IL carotenoid extract (10.8 kJ·mol^− 1) and acetone carotenoid extract (9.4 kJ·mol^− 1). The antioxidant activities of the tomato carotenoid extract were 7.4 and 12.4 relative to α-tocopherol for the ionic liquid extract and acetone extract, respectively. The combination of chromatographic analysis and degradation kinetics provided data for positive assessment similarity of thermal and light stabilities of tomato carotenoids extracted by IL and extracted by acetone.     

Lamb rennet paste in ovine cheese manufacture. Lipolysis and flavour

In a preliminary study with commercial ewe's milk cheeses, there were statistically significant differences in the sensory evaluation scores and the amounts of short-chain (C4–C10) free fatty acids (FFAs) between cheeses made with lamb rennet paste or bovine rennet. Experimental ewe's milk cheeses were manufactured with 2 levels of artisanally produced lamb rennet paste and 2 levels of bovine rennet in 50 L vats, with a manufacturing replicate done within 1 week. Total coagulating activity was 2500 RU for cheeses manufactured with a high amount of rennet or 1000 RU for cheeses manufactured with a low amount of rennet. The two batches of lamb rennet pastes used had 4.0 (early Spring) and 6.5 U g⁻¹ lipase (late Spring), whereas no lipase activity was detected in bovine rennets. The total concentration of FFAs in cheeses manufactured with lamb rennet paste was significantly higher than in cheeses manufactured with bovine rennet, regardless of ripening time and time of the year. Lipolysis in the former cheeses increased with the total units of lipolytic activity added. The increase in lipolysis in cheeses made with lamb rennet was primarily due to higher amounts of short-chain fatty acids (C4–C10). Butyric acid was the main FFA in cheeses made with lamb rennet paste, representing 34.5 μmol 100 μmol⁻¹ (low level of rennet) and 44.2 μmol 100 μmol⁻¹ (high level of rennet) of the total FFAs, whereas it represented only 17 μmol 100 μmol⁻¹ of the total FFAs in all cheeses made with bovine rennet. The concentration of individual FFAs of chain length <C12 were significantly higher in cheeses made with lamb rennet paste than in cheeses made with bovine rennet. Cheeses made with lamb rennet paste received significantly higher intensity scores for odour and flavour intensity, sharp odour, ‘piquant’ and bitter flavours and ‘natural rennet’ odour and flavour.     

Heat-induced Maillard reaction of the tripeptide IPP and ribose: Structural characterization and implication on bioactivity

Maillard reaction products (MRPs) were prepared from aqueous model mixtures containing 60 g L^? 1 ribose and 30 g L^? 1 of the bioactive tripeptide IPP (Ile-Pro-Pro), heated at 98 °C. MRP and associated reactions with changes in IPP were observed within one hour of heat-treatment. The pH of MRPs decreased significantly during the heat treatment of IPP–ribose mixtures from 9.0 to 7.6 after one hour. The amino group content, IPP and ribose concentration decreased significantly during heat treatment. The fluorescence intensity of the IPP–ribose MRPs reached the maximum within 2 h. Modification of the UV/vis spectra for IPP–ribose MRPs was mainly due to a condensation reaction of IPP with ribose. Compounds with molecular weight between 300 and 650 Da were dominant while compounds smaller than 250 Da were also produced during the reactions, as characterized by size exclusion chromatography. Mass spectrometry revealed that IPP was conjugated to ribose at the N-terminal (m/z of 458.3) upon heat-treatment. The presence of ribose also promoted peptide degradation to dehydrated IP (m/z of 211.1). IPP–ribose MRPs lost the known angiotensin-I-converting enzyme (ACE) inhibitory activity of IPP; however, strong antioxidant properties were detected.     

Structure characterization and antitumor activity of an α β-glucan polysaccharide from Auricularia polytricha

A fraction of a 0.05 M NaOH solution-soluble polysaccharide, termed AAFRC, was obtained from Auricularia polytricha by protease-assisted aqueous extraction followed by precipitation with ethanol and purification with gel filtration chromatography. Analysis by high performance liquid chromatography (HPLC) coupled to a TSK-G5000PW_XL column and gel filtration chromatography on Sephacryl S-400HR indicated that AAFRC is homogenous with an average molecular weight (Mw) of about 1.20 × 10⁶ Da. The structure of AAFRC was revealed by chemical methods including Fourier transform infrared (FT-IR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. Results indicated that AAFRC is a glucan consisting 1,3-β-glucan, 1,4-α-glucan, and 1,3-α-glucan backbone with a single 1→)-α-d-glucopyranosyl side-branching unit on every six residues, on average, along the main chain. The growth of transplantable Sarcoma-180 (S₁₈₀) in mice was also significantly inhibited by AAFRC compared with the model controls (P < 0.01), with the inhibitory rate being 43.61%.     

Influence of relative humidity on carbon dioxide sorption in wheat gluten films

The influence of relative humidity (RH) on carbon dioxide sorption at 10⁵ Pa in wheat gluten films (WGF) was investigated in the range of 0–96% RH at 25 °C. The amount of water sorbed by these protein based films reached up to 60% of the dry weight at 96% RH. Carbon dioxide sorption increased with water content, ranging from 2.8 × 10⁻⁴ to 1.9 × 10⁻² mol Pa⁻¹ m⁻³ respectively at 0% and 96% RH. This behavior was tentatively explained on the grounds that sorbed water enhanced carbon dioxide accessibility to protein active sorption sites. The dependence of both the solubility and the diffusivity coefficients of CO₂ and O₂ on WGF water content explains the very good permselectivity of these films observed at high RH values (22 at 93% RH and 25 °C).     

Effects of malting on molecular weight distribution and content of water-extractable β-glucans in barley

In the beer industry β-glucans are extensively studied non-starch polysaccharides due to their ability to increase the viscosity of solutions and to form gels. The current study was designed to determine the total and water-soluble β-glucan contents of barley during malting. Total and water-soluble β-glucans were analyzed from two different malts that originated from the same barley but varied in germination time from 36 h (malt A) to 72 h (malt B). Water-soluble β-glucans were also characterized using high-performance size-exclusion chromatography with triple-detector analysis (HPSEC-TDA) to evaluate the variation in molecular weight distributions, intrinsic viscosity, radius of gyration, Mark–Houwink parameters and polydispersity and thus the overall structural changes during malting. Total β-glucan content decreased from barley to malt due to the action of β-glucanase and was greatest in malt B (where 92% of β-glucans were degraded) which highlights the influence of germination time. β-Glucan solubility increased during malting, again particularly in malt B, where most of β-glucans became soluble. The β-glucanase activity also affected the molecular weight of the polymers which ranged from 298 · 10³ g/mol in barley to 293 · 10³ and 218 · 10³ g/mol in malts A and B respectively. The molar mass of the most abundant fraction decreased from barley (256 · 10³ g/mol) to malt A (112 · 10³ g/mol) and malt B (89 · 10³ g/mol), again highlighting the effect of the longer germination time. Proceeding from barley to malt, the cumulative molar mass distribution function confirmed that the weight fraction of polymers below 200 · 10³ g/mol increased, while the high molecular weight fraction (between 200 · 10³ g/mol and 400 · 10³ g/mol) decreased. Moreover, the presence of a higher molecular weight fraction (14–16%) beyond 400 · 10³ g/mol which does not change during malting was observed. The Mark–Houwink constants α and log k confirmed the random coil conformation of soluble β-glucans and showed an increase in the compactness of the macromolecules from barley to malts.     

Influence of emulsifier type on in vitro digestibility of lipid droplets by pancreatic lipase

The objective of this study was to investigate the influence of interfacial composition on the in vitro digestion of emulsified lipids coated by various emulsifiers by pancreatic lipase. Sodium caseinate, whey protein isolate (WPI), lecithin and Tween 20 were used to prepare corn oil-in-water emulsions (3 wt% oil). Pancreatic lipase (1.6 mg/mL) and/or bile extract (5.0 mg/mL) were added to each emulsion and the particle charge, droplet aggregation, microstructure and free fatty acids released were measured. In the absence of bile extract, the amount of free fatty acids released per unit volume of emulsion was much lower for lipid droplets coated by Tween 20 (13 ± 16 μmol ml⁻¹) than those coated by lecithin (75 ± 20 μmol ml⁻¹), sodium caseinate (220 ± 24 μmol ml⁻¹) or WPI (212 ± 6 μmol ml⁻¹). In the presence of bile extract, there was an appreciable increase in the amount of free fatty acids released in all the emulsions, with the most appreciable effects being observed in the Tween 20-stabilized emulsions. The stability of the emulsions to droplet flocculation and coalescence during hydrolysis was also strongly dependent on emulsifier type, with the WPI emulsions being the least stable and the Tween 20 emulsions being the most stable. Our results suggest that the access of pancreatic lipase to emulsified fats decreases in the following order: proteins (caseinate and WPI) > phospholipids (lecithin) > non-ionic surfactants (Tween 20). These results may have important consequences for the design of foods with either increased or decreased lipid bioavailability.     

Isolation and analysis of macromolecular fractions responsible for the surface properties in native Champagne wines

Macromolecules present in Champagne wines from the three grape varieties Pinot Noir, Meunier and Chardonnay, were isolated by ultra-concentration on 10 K molecular weight cut-off (MWCO) membranes, then purified by dia-filtration and freeze-dried. Measurements of the surface activity of reconstituted wines from the resulting dry ultra-concentrates by ellipsometry showed the formation of adsorption layers analogous to those observed at the surface of native wines, and responsible for their foam stability. Sequential fractionation of Pinot Noir at decreasing MWCO within the 10–30 K and 30–100 K molecular weight range showed the formation of adsorption layers with both fractions. NMR and chemical analysis indicated that all fractions were mainly composed of polysaccharides and proteins. Monosaccharide analysis gave mannose, galactose, arabinose and glucose as the prominent constituting sugars. Careful bottle rinsing was found to enable thorough macromolecule recovery.     

Determination of major metal cations in milk by capillary zone electrophoresis

A reliable and rapid capillary zone electrophoresis method for the determination of the major of cations in milk samples was developed. Sample preparation consisted of dilution, acidification to pH 4.0 with 1 mol L⁻¹ acetic acid and filtration. The complete separation of K⁺, Ca²⁺, Na⁺ and Mg²⁺ could be achieved in 4 min with a simple electrolyte composed of 10 mmol L⁻¹ imidazole and 1 mol L⁻¹ acetic acid (pH 3.6). The running voltage was 25 kV at 25 °C. Indirect UV detection was achieved at 185 nm. Detection limits ranged from 0.06 to 0.57 mg L⁻¹ and quantification limits ranged from 0.16 to 0.62 mg L⁻¹. Precision data showed relative standard deviations (RSD%) lower than 4.1% for relative migration time and 2.4% for milk concentrations, respectively. Recoveries of cations in samples analysed ranged from 97.7% to 101.1%. Thirty samples of milk were analysed, obtaining mean values of 1.46, 1.19, 0.505 and 0.126 g L⁻¹ for K⁺, Ca²⁺, Na⁺ and Mg²⁺, respectively.     

Time–temperature study of the kinetics of migration of DPBD from plastics into chocolate,chocolate spread and margarine

Migration of low molecular weight substances into foodstuffs is a subject of increasing interest and an important aspect of food packaging because of the possible hazardous effects on human health.The migration of a model substance (diphenylbutadiene) from low-density polyethylene (LDPE) was studied in foodstuffs with high fat contents: chocolate, chocolate spread and margarines (containing 61% and 80% fat).A simplifying mathematical model based on Fick’s diffusion equation for mass transport processes from plastics was used to derive effective diffusion coefficients which take also kinetic effects in the foods into account and to determine partition coefficients between plastic and food. With this model migration levels obtainable under other storage conditions can be predicted. The effective diffusion coefficients for both margarines stored at 5 °C (3.0–4.2 × 10⁻¹⁰ cm² s⁻¹) and at 25 °C (3.7–5.1 × 10⁻⁹ cm²  s⁻¹) were similar to each other, lower than for chocolate spread stored at 5 °C (9.1 × 10⁻¹⁰ cm² s⁻¹) and higher than the diffusion coefficient for chocolate stored at 25 °C (2.9 × 10⁻¹⁰ cm² s⁻¹). Good agreement was found between the experimental and the estimated data, allowing validation of this model for predicting diffusion processes in foodstuffs with high fat contents.     

Chemical assay of cyanide levels of short-time-fermented cassava products in the Abraka area of Delta State,Nigeria

Five cassava products, commonly consumed in and around the Abraka area of Delta State, Nigeria were analysed for their cyanide levels. This study, to determine safe levels of cyanide, became necessary as the fermentation time in the processing of these products has been observed to be drastically shortened to as low as 6 h for quick economic returns. In all the products, the cyanide levels were reduced from 30.0–58.0 mg HCN equivalent kg⁻¹ of product. These levels fall below the reported 30.0 mg HCN equivalent kg⁻¹ safe (fresh weight) of raw cassava to 5.4–24.0 mg HCN equivalent kg⁻¹ level for cassava products. Nevertheless, some of the products containing up to 20.0–26.5 g HCN equivalent kg⁻¹ of products are dangerous to health as these levels are higher than the 20.0 mg HCN equivalent kg⁻¹ safe level recommended by the Standard Organization of Nigeria. The current practice of short-time fermentation should therefore be discouraged.     

Determination of moisture,solids-not-fat and fat-by-difference in butter using routine methods according to ISO 8851/IDF 191—an international collaborative study and a meta-analysis

An international collaborative study of routine methods for the determination of moisture, solids-not-fat (SNF) and fat-by-difference (i.e. fat (g 100 g^–1 product) =100−moisture (g 100 g^–1 product)−SNF (g 100 g^–1 product)) in butter was carried out to obtain estimates of the precision parameters repeatability (2.8s_r) and reproducibility (2.8s_R). Ten laboratories tested blind duplicate samples of eight different butters according to standard operating procedures jointly drafted by the International Standards Organisation (ISO) and the International Dairy Federation (IDF) (draft ISO standard 8851, parts 1–3; draft IDF standard 191, parts 1–3). Estimates of repeatability and reproducibility respectively were: moisture, 0.28 g 100 g^–1 product and 0.44 g 100 g^–1 product; SNF, 0.20 g 100 g^–1 product and 0.34 g 100 g^–1 product; fat-by-difference, 0.30 g 100 g^–1 product and 0.51 g 100 g^–1 product. These estimates are similar to those found previously in a New Zealand study. A meta-analysis, pooling the results of the present study and the New Zealand study, yielded overall estimates of repeatability and reproducibility as follows: moisture, 0.31 g 100 g^–1 product and 0.42 g 100 g^–1 product; SNF, 0.20 g 100 g^–1 product and 0.39 g 100 g^–1 product; fat-by-difference, 0.35 g 100 g^–1 product and 0.54 g 100 g^–1 product, and these are recommended for adoption in the respective methods. This study completes the validation work for the respective methods, which may now be progressed for final adoption as international standard routine methods. A protocol is proposed for dealing with situations where multiple precision estimates are available.     

The effect of γ-irradiation on the non-enzymatic browning reaction in the aqueous model solutions

Aqueous solutions of sugars (xylose, arabinose, fructose, glucose or sucrose), alone or in the presence of amino acid (lysine), were γ-irradiated at 0, 5, 10, 20 and 30 kGy at room temperature. Also evaluated were differences between irradiation and heat treatment. Absorbances at 420 nm, of the irradiated sugar–amino acid solutions, were increased although no browning was observed in the irradiated sugar or amino acid alone. The degree of browning of the irradiated sugar–amino acid solution increased with increasing irradiation dose and was dependent on the type of sugar. The non-reducing sugar, sucrose, did not react with lysine by heating for 4 h at 80 °C; however, the irradiated sucrose–lysine solution showed the non-enzymatic browning reaction and it had a higher reactivity than other sugars. For the sugar–lysine solution irradiated at 30 kGy, browning was in the following order of intensity: sucrose > fructose > arabinose > xylose > glucose. Furfural compounds (5-hydroxymethylfurfural and 2-furaldehyde) were not detected in any irradiated samples.     

Methyl ketone production from copra oil by Penicillium roqueforti spores

Bioconversion of copra oil by two strains of Penicillium roqueforti spores was studied in the presence or absence of exogenous lipase. Without exogenous lipase action, methyl ketone productivities were weak: 33 ± 1.9 to 61 ± 2.4 μmol g⁻¹ of oil, respectively, for strains 1 and 2. This formation results from the bioconversion of free fatty acids present in copra oil and appears strain-dependent. The major ketone was 2-undecanone, reflecting the high concentration of dodecanoic acid in the substrate. After lipolysis of copra oil by a Candida cylindracea lipase, a large increase of methyl ketone productivities (912 ± 13 and 1935 ± 26 μmol g⁻¹ of oil, respectively) is noticed with 2-heptanone predominating. This observation could result from the selectivity of the lipase used in the bioconversion process, or from the preferential oxidation due to spore specificity. When the reaction time was increased, the amount of methyl ketones decreased and other volatile compounds were formed..     

Activation energy measurements in rheological analysis of cheese

Activation energy of flow (E_a) between 30 and 44 °C was calculated from temperature sweeps of cheeses with contrasting characteristics to determine its usefulness in predicting rheological behavior upon heating. Cheddar, Colby, whole milk Mozzarella, low-moisture part-skim Mozzarella, Parmesan, soft goat, and Queso Fresco cheeses were heated from 22 to 70 °C, and E_a was calculated from the resulting Arrhenius plots. Protein and moisture content were highly correlated with E_a. The E_a values for goat cheese and Queso Fresco, which did not flow when heated, were between 30 and 60 kJ mol^?1. Cheddar, Colby, and the Mozzarellas did flow upon heating, and their E_a values were between 100 and 150 kJ mol^?1. Parmesan, the hardest cheese, flowed rapidly with heat and had an E_a > 180 kJ mol^?1. E_a provides an objective means of quantitating the flow of cheese, and together with elastic modulus and viscous modulus provides a picture of the behavior of cheese as it is heated.     

Pressurized aqueous ethanol extraction of β-glucans and phenolic compounds from waxy barley

Beta-glucans and phenolics were extracted from waxy barley using pressurized aqueous ethanol in a stirred batch reactor at 25 bar and 500 rpm. The effect of temperature (135–175 °C), extraction time (15–55 min) and ethanol content (5–20%) was evaluated. Temperature had an opposite effect on the extraction of both compounds. The higher the temperature, the lower the β-glucan extraction yield due to fragmentation, but a significant increase on the phenolic recovery was observed. Long extraction times favored the extraction of β-glucans at low temperatures and phenolics at any temperature. The ethanol content was not statistically significant on the β-glucan extraction, but helped to maintain the molecular weight of the extracted β-glucan. To obtain liquid extracts rich in high molecular weight β-glucans and phenolics, mild conditions of 151 °C, 21 min and 16% ethanol are needed, leading to 51% β-glucan extraction yield with a molecular weight of 500–600 kDa and 5 mg GAE/g barley.     

Effect of ractopamine hydrochloride (Optaflexx) dose on live animal performance,carcass characteristics and tenderness in early weaned beef steers

Study objectives were to evaluate ractopamine hydrochloride's (RAC) effect on performance, carcass characteristics, and tenderness of early weaned beef steers. Steers were assigned to a control diet (0 mg RAC·steer^− 1·d^− 1), 200 mg RAC mg·steer^− 1·d^− 1, or 300 mg RAC·steer^− 1·d^− 1. Steers fed 200 and 300 mg RAC·steer^− 1·d^− 1 gained 14.84 kg and 14.57 kg more live weight and produced 13.22 and 14.90 kg more hot carcass weight, respectively, than controls. Feed conversions for steers fed 200 or 300 mg RAC·steer^− 1·d^− 1 of RAC increased 45.2% and 47.3% and average daily gain increased 55.5% and 54.5% compared to controls, respectively. Feeding either dose of RAC increased (P < 0.05) loin muscle area and increased (P < 0.05) Warner–Bratzler shear force (WBSF) values compared to controls, however the magnitude of WBSF difference diminished (P > 0.05) over 14 days of postmortem aging. Results of this study confirm that RAC increases weight gain and feed efficiency, minimally impacts carcass quality and has manageable impacts on tenderness when fed at either 200 or 300 mg steer^− 1·d^− 1.