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The physical stability of oil-in-water emulsions containing β-carotene was investigated to assess the emulsification of three hydroxypropyl methylcellulose (HPMC) of varying substitution and viscosity and gum acacia (GA) control dispersions. Initially, emulsions stabilized with GA had particle sizes of 0.79 μm, whereas the HPMC stabilized emulsions possessed particle sizes of about 1.38–1.96 μm. Following storage at 25 °C or 37 °C for up to 12 days, no significant differences between the initial and final particle sizes for two of the three HPMC stabilized emulsions (P < 0.05) were observed and remained <2.0 μm. However, the particle size distributions changed with time of storage at 25 °C or 37 °C in all emulsions, but were minimal in the emulsion containing the highest initial viscosity HPMC (0.401 Pa s). Images from light microscopy demonstrated that variability in droplet sizes was more prominent in low viscosity, low M:HP HPMC stabilized emulsions. Small amplitude oscillatory shear measurements revealed that the HPMC that possessed a viscosity of 0.401 Pa s and high M:HP (4.45) displayed characteristics of a weak gel network, which likely provided additional resistance against particle size increase. The analysis of the data demonstrates that HPMC with high viscosity, high M:HP produce emulsions with greater physical stability. [ABSTRACT FROM AUTHOR]

Sugar beet pectin (SBP) and β-lactoglobulin (BLG) contain ferulic acid and tyrosine, respectively, potential substrates for laccase. Dispersions of BLG were treated with laccase and/or heat and SBP to assess potential for ferulic acid in SBP to influence laccase conjugation of BLG. Changes were investigated by size exclusion chromatography combined with multi angle laser light scattering (HPSEC-MALLS), refractive index (RI) and UV detector, particle size and ζ-potential analysis. Molecular weight (MW) of BLG decreased from 3.7 × 104 to 2.9 × 104 and root mean square (RMS) decreased from 41 to 36 after laccase treatment. The slope of a conformation plot increased from 0.35 to 0.72, indicating a change in shape in laccase treated BLG to more random coil. While laccase did not affect MW of BLG, MW of BLG increased after sequential heat and laccase treatment to 2.9 × 106 and 4.4 × 106, respectively. Free thiol (SH) increased by heat and laccase treatment of BLG; tyrosine in BLG increased only by heat. An increased MW and decreased ferulic acid in SBP was observed in the presence of BLG and laccase. The increase in MW was attributed to entrapment of BLG in SBP cross-linked matrix catalyzed by laccase. [ABSTRACT FROM AUTHOR]

Abstract: Enzymatic liquefaction of jicama (Pachyrhizus erosus) tuberous roots increases the yields of juice. Jicama tuberous root was disintegrated by Pectinex Ultra SP-L (≥3800 U/mL). Juice volume, glucose and alcohol insoluble solids (AIS) were determined. Remaining cell walls were characterized by infrared spectroscopy. AIS were destarched using amylolytic enzymes and analyzed by gas chromatography. The aim of this research was to evaluate the effect of enzymatic liquefaction of jicama tuberous root on juice volume, glucose and quantification and characterization of alcohol insoluble solids (AIS). The highest volume of juice was 980 mL/kg tuberous root. The range for maximum glucose was 58.0–75.8 g/kg tuberous root and the lowest for residual AIS was in the range of 15.5–24.6 g/kg tuberous root after 10 h with 0.024 mL/g of enzyme per kg at 40 °C. Infrared spectra showed signals corresponding to low methoxylated pectins, proteins and starch. Destarched jicama cell walls gas chromatograms revealed a decrease in sugars after liquefaction except in xylose, glucose and mannose which increased as a result of this process. Hydrolyzed jicama tuberous root is a good source of high glucose syrups and destarched cell walls may need enzyme rich in xylanase to reduce residue further. [Copyright &y& Elsevier]

Abstract: Optimized jicama root liquefaction allows to obtain the highest weight loss and sugars content to recover by-products such as food ingredients, biofuels, organic acids, etc. Jicama (Pachyrhizus erosus L.) tissue was treated with Pectinex Ultra SP-L. Optimization of jicama liquefaction and saccharification was done using Response Surface Methodology and Response Surface Methodology-Spline. A mixture of sodium acetate buffer (AAANa) at pH 4.5 and enzyme ratio (mL/g of jicama cubes) of 0.000, 0.008, 0.012, 0.020 and 0.024 were used. Samples were incubated under shaking (150 rpm) for 0.00, 4.24, 10.00, 14.24 and 16.00 h at 40 °C. At the optimum conditions (10 h and 0.024 mL/g) the pH was 4.24, total soluble solids (°Brix) amount was 9.00, weight loss percentage was 95.82%, the total and reducing sugars liberated were 119.0 and 63.8 g/kg, respectively. Uronic acids obtained were 5.7 g/kg and polyphenols amount was 26.8 mg/kg. [Copyright &y& Elsevier]

Large numbers of fruits from Palmyra palm ( Borassus aethiopum Mart), a common, native tree of tropical regions, are underutilized and left to spoil. This work was conducted to assess pectin content of Palmyra palm fruit, and to develop a reliable protocol for pectin extraction. Yield and galacturonic acid content of Palmyra palm fruit soluble solids were investigated at various pH (natural pH of 5.2–5.5, 2.5, 7), time (30–120 min) and temperature (70 °C, 80 °C, 90 °C). Yield and galacturonic acid content of extracted soluble solids were strongly dependent (p < 0.0001) on temperature, time and pH of extraction and ranged from 47 to 149 g kg−1 and 682 to 880 g kg−1 dry weight, respectively. High galacturonic acid (808–852 g kg−1) were obtained at 70 °C and 90 °C under natural pH; at 70 °C pH 7 and pH 2.5 at all temperatures studied. Analysis of pectin extracted at natural pH (30 min, 90 °C) revealed highly esterified pectin with good gelling and emulsifying properties. Production of galacturonic acid of more than 650 g kg−1 dry weight indicates that Palmyra palm fruit could serve as an excellent raw material for industrial pectin production. [ABSTRACT FROM AUTHOR]

Abstract: Rapid and non-destructive quality methods that can rapidly scan large product numbers in early stages of production are attractive for meat production. Chicken breast muscles from low- and high-growth rate (GR) broilers were segregated into extremes of broilers with weight gain of ≤250 g/wk and ≥299 g/wk, respectively. Breast muscle was also segregated into extremes of low- and high-water holding capacity (WHC) of ≤4.08g/100 g or ≥ 89.26g/100 g muscle, respectively. Raman spectroscopy was used to evaluate differences in spectra of the extremes of broilers that differed in GR or muscle that differed in WHC. Spectra was collected at 785 nm excitation, 500 mW laser power, 10 s total integration time. There were 7 significantly different bands (P < 0.05) from growth rate population spectrum: 510, 1270, 1354, 1535, 1652, 1737, 1863 cm−1; and 4 significantly different bands (P < 0.05) from WHC population spectrum: 538, 691, 1367, 1743 cm−1. Differences in the trptophan environment, cysteine and amide I and III structure influenced WHC. The results can potentially be used to rapidly identify muscle attribute variations for customized handling in further processing. [Copyright &y& Elsevier]

Abstract: The objectives of this study were to determine the effect of microencapsulation method on physical properties and in vitro release and bioavailability of three types of β-carotene: a spray-dried powder of β-carotene and maltodextrin, commercially available water-dispersible β-carotene powder, and chitosan-coated β-carotene alginate. In vitro digestion trials were conducted with and without food matrices (yogurt, pudding) to elucidate the effect of food matrix on in vitro release and bioavailability. Microencapsulation method significantly affected (p < 0.05) water activity, moisture content, and particle size. The maltodextrin powder had the lowest moisture content (3.5%) and the smallest volume mean diameter (10.5 μm), whereas the chitosan-alginate beads had the lowest water activity (0.195). The maltodextrin powder had the highest surface β-carotene content (39.5%), while the commercial water-dispersible powder had the highest β-carotene content (10%). The microencapsulation method significantly influenced (p < 0.05) release and incorporation into micelles, regardless of food matrix. Water-dispersible β-carotene achieved the highest release (93.3%) and the highest incorporation into micelles (36.4%) in the absence of a food matrix, and the highest release (34.8%) and the highest micelle content (17.0%) with pudding. Food matrix significantly decreased release and micelle incorporation (p < 0.05), with yogurt decreasing release and micelle incorporation more than pudding. [Copyright &y& Elsevier]

Pectin is a co-product from juicing and the physico-chemical quality is important to functionality of pectin in food and pharmaceutical applications. Juice and peel from Huanglongbing (HLB) control and infected Valencia oranges were analyzed. Infected fruit had smaller diameter, lower L* and b* values and highly variable a* values. Juice from infected fruit had higher pectinmethylesterase (PME) activity of 1.5 Units/mL, which retained higher activity during 15 days of storage at 4 °C, and juice had higher cloud loss. Also, the juice obtained from infected fruit had lower °Brix (8.5–8.9), higher titratable acidity (0.71–0.88%), and lower pH (3.45–3.75). Molecular weights of 154–157 kDa and degrees of esterification of 65–67% were similar. Pectin yield from dried peel was reduced by 6% in infected fruit to 4.18 g/100 g. Total neutral sugars in pectin from control fruit were higher, 84.1 μg/mg, compared to infected fruit, 60.7 μg/mg. Glucose, galactose, and arabinose, were higher in control fruit, 25.0, 40.8, and 9.7 μg/mg, compared to 14.5, 27.4, and 8.3 μg/mg in infected fruit. Viscosity was 0.015 Pa s, in 1% pectin from control or infected fruit (p > 0.05). Juice quality, including cloud stability, was negatively impacted by HLB, however pectin functionality was minimally impacted. • Huanglongbing negatively impacts citrus juice ◦Bx, pH, titratable acidity, color. • Juice from infected fruit has higher pectinmethylesterase activity and cloud loss. • Lower yield of pectin from peel was obtained from infected fruit. • Pectin is similar in control or infected fruit. [ABSTRACT FROM AUTHOR]