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Background: Response surface methodology (RSM) was used in a sequential manner to optimize solubilization and precipitation conditions in the recovery of protein from bovine lung using pH shift., Results: Separate D-optimal designs were employed for protein solubilization and precipitation. Independent variables investigated for protein solubilization were time (10-120 min), temperature (4-20 °C), pH (8.0-11.0) and solvent/sample ratio (2.5-10). Variables for protein precipitation were time (0-60 min) and pH (4.25-6.00). Soluble protein yields ranged from 323 to 649 g kg -1 and the quadratic model for protein solubilization revealed a coefficient of determination R 2 of 0.9958. Optimal conditions for maximum protein solubility were extraction time 140 min, temperature 19 °C, pH 10.8 and solvent/sample ratio 13.02. Protein precipitation yields varied from 407 to 667 g kg -1 , giving a coefficient of determination R 2 of 0.9335. Optimal conditions for maximum protein precipitation were pH 5.03 and 60 min. Based on the RSM model, solubilization conditions were manipulated to maximize protein solubilization under reduced water and alkaline usage. These conditions were also validated., Conclusion: Models for solubilization and precipitation using bovine and porcine lung were validated; predicted and actual yields were in good agreement, showing cross-species applicability of the results. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

The effects of sodium tripolyphosphate (STPP), two sources of starch (potato starch: PS and rice starch: RS) and comminution degree (CD) on the technological, instrumental and sensory characteristics of reformed hams were studied using response surface methodology. Both starches reduced cook loss and decreased ham flavour intensity, but RS had stronger effects on instrumental measures of texture, while PS was associated with improved juiciness when low/no added STPP was included. Coarsely ground meat, processed 100% with the kidney plate was associated with slightly increased cook loss, reduced texture profile analysis parameters and a more intense ham flavour compared to the other treatment (80% ground with a kidney plate plus 20% with a 9mm plate). STPP was the sole factor affecting overall liking. If starch is included in the formulation, the standard level of STPP (0.3%) can be reduced by half with no increase in cook losses, but some decline in sensory quality cannot be avoided., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The effects of fat substitution (≤ 15%) with commercial encapsulated and unencapsulated fish oils on the technological and eating quality of beef burgers over storage [modified atmosphere packs (80% O2:20% CO2); constantly illuminated retail display at 4 °C; for 15 days] were studied using design of experiment (DOE). Burger formulations comprised beef shin (59.5%), salt (0.5%), vitamin E (0.015%) combined with varying levels of beef-fat/fish oils depending on the treatment. Increasing amounts of encapsulated and unencapsulated fish oils in burgers increased polyunsaturated fatty acid content (P < 0.001). Storage decreased (P < 0.001) a* values, which was in agreement with oxymyoglobin data. Vitamin E inclusion in burgers resulted in higher (P < 0.01) oxymyoglobin values. TBARS values increased (P < 0.001) over storage as expected. Fat substitution with unencapsulated oils increased cook loss (P < 0.001) and decreased hardness (P < 0.05) compared to other treatments. Optimisation predicted a burger formulation with 7.8% substitution in beef-fat with encapsulated fish oil. Panellists scored the optimised burger formulation (P < 0.05) lower than controls for overall acceptability., (Copyright © 2015. Published by Elsevier Ltd.)

The impact of pulsed electric field (PEF) processing conditions on the distribution of water in carrot tissue and extractability of soluble sugars from carrot slices was studied. Time domain NMR relaxometry was used to investigate the water proton mobility in PEF-treated carrot samples. Three distinct transverse relaxation peaks were observed in untreated carrots. After PEF treatment only two slightly-overlapping peaks were found; these were attributed to water present in the cytoplasm and vacuole of carrot xylem and phloem tissues. This post-treatment observation indicated an increase in water permeability of tissues and/or a loss of integrity in the tonoplast. In general, the stronger the electric field applied, the lower the area representing transverse relaxation (T 2 ) values irrespective of treatment duration. Moreover an increase in sucrose, β- and α-glucose and fructose concentrations of carrot slice extracts after PEF treatment suggested increases in both cell wall and vacuole permeability as a result of exposure to pulsed electric fields., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The effects of fat substitution using two commercial inulin products on the physico-chemical properties and eating quality of a comminuted meat product (breakfast sausage) were modelled using a specialised response surface experiment specially developed for mixtures. 17 treatments were assigned representing a different substitution level for fat with inulin. Sausages were formulated to contain pork shoulder, back fat/inulin, water, rusk and seasoning (44.3, 18.7, 27.5, 7 and 2.5% w/w). Composition, sensory, instrumental texture and colour characteristics were assessed. Fructan analysis showed that inulin was unaffected by heat or processing treatments. Models showed increasing inulin inclusions decreased cook loss (p<0.0017) and improved emulsion stability (p<0.0001) but also resulted in greater textural and eating quality modification of sausages. Hardness values increased (p<0.0001) with increasing inulin concentration, with panellists also scoring products containing inulin as less tender (p<0.0112). Optimisation predicted two acceptable sausage formulations with significantly lower fat levels than the control, which would contain sufficient inulin to deliver a prebiotic health effect., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The aim of the present study was the evaluation of high hydrostatic pressure (HHP) processing on the levels of polyphenolic compounds and selected quality attributes of fruit smoothies compared to fresh and mild conventional pasteurization processing. Fruit smoothie samples were thermally (P(70) > 10 min) or HHP processed (450 MPa/1, 3, or 5 min/20 °C) (HHP1, HHP3, and HHP5, respectively). The polyphenolic content, color difference (ΔE), sensory acceptability, and rheological (G'; G''; G*) properties of the smoothies were assessed over a storage period of 30 days at 4 °C. Processing had a significant effect (p < 0.001) on the levels of polyphenolic compounds in smoothies. However, this effect was not consistent for all compound types. HHP processed samples (HHP1 and HHP3) had higher (p < 0.001) levels of phenolic compounds, for example, procyanidin B1 and hesperidin, than HHP5 samples. Levels of flavanones and hydroxycinnamic acid compounds decreased (p < 0.001) after 30 days of storage at 2-4 °C). Decreases were particularly notable between days 10 and 20 (hesperidin) and days 20 and 30 (chlorogenic acid) (p < 0.001). There was a wide variation in ΔE values recorded over the 30 day storage period (p < 0.001), with fresh and thermally processed smoothies exhibiting lower color change than their HHP counterparts (p < 0.001). No effect was observed for the type of process on complex modulus (G*) data, but all smoothies became less rigid during the storage period (p < 0.001). Despite minor product deterioration during storage (p < 0.001), sensory acceptability scores showed no preference for either fresh or processed (thermal/HHP) smoothies, which were deemed acceptable (>3) by panelists.

The functionality of pre-rigor beef was investigated in terms of the effects of phosphate reduction and curing of hot-boned meat on the processing and sensory properties of relatively low-value muscles, M. infraspinatus (IS) and M. pectoralis profundus (PP), from the forequarter. Muscles were excised within 90 min post-mortem (HB) or, from chilled carcasses, 24 h post-mortem (CB), and were injected to 115% of green weight with brine containing phosphate and were vacuum tumbled continuously for 2 h. Hot-boning gave lower total yield of cooked meat for both muscles. Hot-boned PP joints had slightly higher (P<0.05) cook loss than cold-boned. Reduction of added phosphate (from sodium tri-polyphosphate) from 0.3% to 0.15% of cured meat had detrimental effects on colour; joints containing the conventional 0.3% were lighter (P<0.001) and redder for both muscles. Hot-boning gave PP joints which were rated less tender by sensory panels, corresponding with higher (P<0.001) hardness TPA values, higher (P<0.05) Warner-Bratzler shear force (WBSF) values and shorter (P<0.05) sarcomere lengths. Effects of phosphate level and boning method were less in IS joints. In these, hot-boning gave products that were rated by sensory panel as slightly more tender but there was no effect on TPA or WBSF values. Furthermore, total yields from hot-boned products did not reflect the expected increase in functionality and reducing added phosphate during processing had a detrimental effect in binding and forming of joints., (2009 Elsevier Ltd. All rights reserved.)