The effect of different levels of sunflower head pith addition on the properties of model system emulsions prepared from fresh and frozen beef

The effect of sunflower head pith on the functional properties of emulsions was studied by using a model system. Oil/water (O/W) model emulsion systems were prepared from fresh and frozen beef by the addition of the pith at five concentrations. Emulsion capacity (EC), stability (ES), viscosity (EV), colour and flow properties of the prepared model system emulsions were analyzed. The pith addition increased the EC and ES and the highest EC and ES values were reached when 5% of pith added; however, further increase in the pith concentration caused an inverse trend in these values. Fresh beef emulsions had higher EC and ES values than did frozen beef emulsions. One percent pith concentration was the critic level for the EV values of fresh beef emulsions. EV values of the emulsions reached a maximum level at 5% pith level, followed by a decrease at 7% pit level.     

The effects of different plant oils on some emulsion properties of beef, chicken and turkey meats

The effects of different plant oils (soybean, hazelnut, canola, sunflower, corn, cotton and olive) on emulsion capacity (EC), emulsion stability (ES), emulsion density (ED) and apparent yield stress values of emulsion (raw emulsion; AYSe) and emulsion gel (cooked emulsion; AYSg) of beef, chicken and turkey meats were studied by using a model system. Olive oil increased EC, AYSe and AYSg values and corn oil increased ES values significantly (P < 0.01). Moreover, olive oil decreased ED values significantly (P < 0.01). The effects of chicken meat on EC, turkey meat on ES and beef on AYSe were found to be significant (P < 0.01). The plant oils increased EC values of chicken meat significantly (P < 0.01). Olive oil had higher effect on EC values of chicken, beef and turkey meat. It was found to be 140.7, 132.5 and 128.9 mL (450 mg)⁻¹ protein, respectively. However, olive oil had higher effect on AYSg values of turkey, chicken and beef. It was found to be 492.9, 492.3 and 487.7 Nm⁻², respectively. In addition, olive oil decreased ED values of beef significantly (P < 0.01). The effect of corn oil on ES values of beef was found to be higher (P < 0.05) as 75.77%.     

Quality characteristics of a non‐fermented dry‐cured sausage formulated with lemon albedo

Dry‐cured sausages were treated with two types of dehydrated lemon albedo (raw and cooked) at five concentrations (0–100 g kg^?1 in 25 g kg^?1 increments). Several physical and chemical analyses were made during the drying stage, and compositional, textural and sensory analyses were conducted on the finished products. The addition of albedo improved the nutritional properties as a result of fibre addition and may have beneficial effects due to the presence of active biocompounds as evidenced by a decrease in residual nitrite levels and delayed oxidation (based on TBARS values). The sensory properties of samples that resembled the control sausages were those that contained up to 50 g kg^?1 dehydrated raw albedo and 75 g kg^?1 dehydrated cooked albedo. Copyright © 2004 Society of Chemical Industry     

Mechanical and gelling properties of comminuted sausages containing chicken MDM

The present investigation focuses on the physicochemical properties, rheological behaviors and texture of raw and cooked emulsions containing different mechanically deboned meat (MDM) from chicken. MDMs were produced from the neck, backs and thighs. The texture and mechanical profile analyses were performed using a small deformation dynamic oscillation in a shear and instrumental texture analyzer. The mechanical spectra of the raw and cooked MDM emulsion gels were classified as weak gels based on their frequency sweep and tan δ results. Both the G′ and G″ values increased with increasing frequency in the temperature of 4 and 10 °C. The MDM from thighs had the lowest water holding capacity (WHC) and emulsifying (EC) values, while the MDM from backs had significant values of 2.41 and 128.87, respectively. The cooked emulsion containing backs showed the highest hardness and cohesiveness values, while the emulsion containing necks and thighs had the lowest texture parameters.     

Emulsifying characteristics of commercial canola protein–hydrocolloid systems

Emulsifying properties of commercial canola protein isolate (CPI)–hydrocolloid-stabilized emulsions were evaluated under varied conditions (CPI, salt and hydrocolloid concentrations; pH, denaturants). Emulsifying activity index (EAI) and emulsion stability (ES) were determined by turbidimetric testing. The results showed that under complexing conditions (at pH 6), the addition of 1% (w/v) κ-carrageenan (κ-CAR) increased the EAI of CPI-stabilized emulsions from 162 to 201 m²/g and ES from 68% to 95%. Under conditions promoting incompatibility (at pH 10), the use of 1% (w/v) guar gum increased the EAI of CPI-stabilized emulsions from 68 to 177 m²/g and ES from 66% to 100%. The lower EAI and ES values observed in CPI–hydrocolloid-stabilized emulsions treated with sodium salts and denaturants support the involvement of hydrophobic interactions, hydrogen bonds and disulfide linkages in the emulsification of these systems. Interfacial properties of CPI–hydrocolloid mixtures were improved by electrostatic complexing and incompatibility, making these systems suitable for stabilizing food emulsions.     

Utilization of Lemon Albedo in Dry-cured Sausages

Two types of lemon albedo (raw and cooked) at 5 concentrations (0% to 10% in 2.5% increments) were added to dry‐cured sausages, and compositional, textural, and sensory analyses were conducted on finished products. The addition of albedo provided an improvement in nutritional properties from fiber addition and may have beneficial effects due to the presence of active biocompounds as evidenced by a decrease in residual nitrite levels and delayed oxidation (based on CIE redness values). Products with sensory properties similar to control sausages were those that contained 2.5% raw albedo and 2.5%, 5%, and 7.5% cooked albedo.     

Optimization of emulsion characteristics of beef, chicken and turkey meat mixtures in model system using mixture design

Emulsion pH (pHe), emulsion capacity (EC), emulsion stability (ES), emulsion density (ED) and apparent yield stress of emulsion (raw emulsion, AYSe) and emulsion gel (cooked emulsion, AYSg) of beef, chicken and turkey meats and their mixtures were studied using a model system.

Turkey meat homogenate was found to have higher protein concentration than chicken or beef homogenates. The highest pHe, EC and ES values and the lowest ED and AYSe values were found in chicken meat. However, the highest AYSg value was found in chicken–turkey meat mixture. Generally, the increasing amount of chicken meat in mixtures increased EC and ES, and decreased ED and AYSe values. Also, chicken–turkey meat mixtures had lower ES values than the mixtures containing only chicken or only turkey meat. With beef, the addition of chicken and turkey meats improved emulsion characteristics significantly. Optimum levels of beef, chicken and turkey meats were found to be 0–23%, 9–30% and 53–91% respectively.     

Effects of pH and chitosan on beef emulsion properties

Effects of pH (3.75–8.25) and chitosan (0–0.36%) on emulsion capacity (EC), emulsion stability (ES) and apparent yield stress values of emulsion (raw emulsion; AYSe) and emulsion gel (cooked emulsion; AYSg) of beef were studied by using a model system. Chitosan increased ES, AYSe and AYSg values of beef in the acidic medium. However, EC increased with increasing pH and chitosan levels until a critical point, which was determined to be at pH 5.87 and a chitosan level of 0.218%. The interaction effects of chitosan and pH on ES, AYSe and AYSg were also found to be significant ( P  <   0.01).     

Lemon albedo as a new source of dietary fiber: Application to bologna sausages

The aim of this work was to study the effect of the addition of lemon albedo in bologna sausages. Two types of albedo (raw and cooked) and five concentrations (0%, 2.5%, 5%, 7.5% and 10%) were added to sausages. Chemical, physicochemical and sensory analyses were made. The addition of albedo to bologna sausages represents an improvement in their nutritional properties and may have beneficial effects, possibly due to the presence of active biocompounds which induce a decrease in residual nitrite levels. The formulations which gave products with sensory properties similar to conventional sausages were sausages with 2.5% and 5% raw albedo and 2.5%, 5% and 7.5% cooked albedo.     

Effect of kimchi powder level and drying methods on quality characteristics of breakfast sausage

This study was conducted to determine the effect of the addition of kimchi powder on the quality characteristics of meat batter and breakfast sausage. Breakfast sausages were supplemented with freeze dried kimchi powder (FKP) or hot air dried kimchi powder (HKP) at levels of 1% (FKP-1 and HKP-1) or 2% (FKP-2 and HKP-2). The emulsion stability, cooking yield, and apparent viscosity in meat batters improved with increments of kimchi powder (p < 0.05). Increased levels of kimchi powder in breakfast sausage decreased the L^∗ value, pH, and springiness, and increased the a^∗ value, b^∗ value, hardness, chewiness, and gumminess (p < 0.05). Sensory evaluations indicated that a higher overall acceptability was attained when the kimchi powder was added to breakfast sausage at a level of 2%.     

Characterisation of fish oil emulsions stabilised by sodium caseinate

Fish oil emulsions varying in sodium caseinate concentration (25% w/w oil and 0.1–1.0% w/w protein, giving oil-to-protein ratios of 250–25) were investigated in terms of their creaming stability, rheological properties, the mobility of oil droplets and the oil/protein interaction at the interface. The presence of excessive protein in an emulsion (i.e., at 1% w/w) caused the aggregation of oil droplets through depletion flocculation, resulting in low creaming stability and high low-shear viscosity. At a lower protein concentration (0.1% w/w), when protein was limited, the emulsion droplets were stabilised by bridging flocculation and showed good stability to creaming. Shear-thinning behaviour was observed for both flocculated emulsions. A reduction in the low-shear viscosity and a Newtonian flow was obtained for the emulsion containing an intermediate concentration of protein (0.25% w/w). At this concentration, there was relatively little excess unadsorbed protein in the continuous phase; thus the emulsion was most stable to creaming. NMR was used to characterise these emulsion systems without dilution. Shorter T₂ values (by low-field ¹H NMR), for the emulsions containing both high (1% w/w) and low (0.1% w/w) amounts of protein, indicated increased restricted mobility of oils, caused by depletion or bridging flocculation. The line broadening in oil signals in the high-field NMR spectra (¹H, ¹³C) indicated increased interaction between oil molecules and proteins at the interface with increasing protein concentration in emulsions. In addition, ³¹P NMR spectra, which reflect the mobility of the casein component only, showed increased line broadening, with reduction in protein content due to the relatively higher proportion of the protein being adsorbed to the interface of the oil droplets, compared to that in the continuous phase (i.e., as the oil-to-protein ratio was increased). The T₂ values of resonances of the individual groups on oil molecules, obtained using high-field ¹H NMR, reflected their different environments within the oil droplet.     

Emulsifying properties of proteins extracted from Australian canola meal

Canola protein albumin fraction, globulin fraction, and canola protein isolate (CPI) were compared to commercial soy protein isolate (SPI) in terms of their emulsifying properties at various pH values. The globulin fraction had higher emulsifying capacity (EC), higher emulsifying activity index (EAI), and the droplet size of emulsions it stabilized was consistently smaller irrespective of pH compared to albumin fraction or CPI. In comparison to SPI, globulin fractions also had higher EC at all pH values tested, higher EAI at acidic pH, and smaller or comparable average emulsion droplet size at both pH 4 and 7. The stability of canola protein based emulsions were comparable to those of SPI based emulsions at most pH values (except the emulsion stabilized by the CPI at pH 4), with no significant (p > 0.05) changes in droplet size during storage for up to 7 days at room temperature. These emulsions, however, experienced separation into the emulsion and serum phases after 24 h storage at room temperature with the exception of CPI- and SPI-stabilized emulsions at pH 9. This study demonstrates the comparable emulsifying properties (forming or stabilizing) of some canola proteins to commercially available SPI, suggesting the potential use of canola proteins in food applications.     

Real-time measurement of oxygen transport across an oil-water emulsion interface

A method for real-time, in situ measurement of oxygen transport across oil-in-water emulsion interface was developed. This method is based on reversible fluorescence quenching of tris ruthenium (II) bis (hexafluorophosphate) complex dye encapsulated in the oil phase of an emulsion upon interaction with oxygen. Oxygen transport across the oil-water interface for four different emulsions (whey protein isolate (WPI), sodium-dodecyl sulphate (SDS), cross-linked WPI and SDS-chitosan emulsions) was measured and effective diffusion coefficients were calculated. Results show that cross-linking of WPI did not alter the oxygen transport rate (p > 0.01), while addition of a chitosan layer to the SDS emulsion significantly reduced the oxygen transport rate (p < 0.01). An increase in temperature from 25 to 40 °C reduced the oxygen transport rate in WPI and cross-linked WPI emulsions (p < 0.01). Effective diffusion coefficient values for transport of oxygen based on fluorescence data were 0.14-1.15 × 10⁻¹² cm²/s for the tested emulsions. Regardless of relatively low effective diffusion coefficients, the selected emulsions exhibited poor barrier properties in limiting oxygen transport across an emulsion interface. In summary, this rapid method is sensitive to detect changes in rate of oxygen transport due to changes in temperature and chemical composition of emulsion interface. This method can be used to screen and evaluate the barrier properties of encapsulation matrices leading to rational design of encapsulated structures.     

The effects of shelf-life enhancers on E. coli K12 survival in needle-injected, surface contaminated beef strip steaks enhanced using recycled solutions

The objective of this study was to evaluate the efficacy of shelf-life enhancers (sodium lactate [SL] or sodium lactate + sodium diacetate [SLDA]) on limiting the growth of Escherichia coli K12 in needle-injecting surface-contaminated beef strip steaks with recycled enhancement solutions. Strip loins were injected to 10% over initial weight. SLDA was most effective in controlling bacterial growth followed by SL alone. The salt/phosphate combination in the enhancement solution was ineffective. SL decreased a^∗ (less red) and b^∗ values (less yellow) of the steaks compared to the salt/phosphate control. SLDA decreased L^∗ values compared to SL alone. SL and SLDA were equally effective in reducing purge loss from the steaks. Steaks enhanced with a “fresh” enhancement solution had higher a^∗ values (more red) and higher E. coli contamination levels than steaks enhanced with recycled solutions. Recycling did not affect L^∗ value, b^∗ value, or purge loss.     

Partial replacement of nitrite by annatto as a colour additive in sausage

For decreasing the use of nitrite in sausage in industrial conditions, annatto (Bixa orellana L.) powder (1% norbixin) was used in two different formulations of sausage (with 55% and 70% of meat) as a replacement for 20%, 40%, 60%, 80% and 100% nitrite. Then the qualitative characteristics of the samples such as colour (L^∗, a^∗ and b^∗), microbial contamination and sensory tests (flavour and odour) were compared with the control (without annatto and with 100% nitrite) after 2, 10, 20 and 30 days from production and under the refrigerated condition. The Statistical comparison showed that in both formulations of sausage, the sample containing 60% annatto was the best sample for its colour (for higher a^∗ and lower b^∗); yet, this sample also did not show any significant differences from the control for microbial contamination and sensory properties.     

Tensile properties of cooked meat sausages and their correlation with texture profile analysis (TPA) parameters and physico-chemical characteristics

The possibilities of using breaking strength (BS) and energy to fracture (EF) for monitoring textural properties of some cooked meat sausages (chopped, mortadella and galantines) were studied. Texture profile analysis (TPA), folding test and physico-chemical measurements were also performed. Principal component analysis enabled these meat products to be grouped into three textural profiles which showed significant (p < 0.05) differences mainly for BS, hardness, adhesiveness and cohesiveness. Multivariate analysis indicated that BS, EF and TPA parameters were correlated (p < 0.05) for every individual meat product (chopped, mortadella and galantines) and all products together. On the basis of these results, TPA parameters could be used for constructing regression models to predict BS. The resulting regression model for all cooked meat products was BS = −0.160 + 6.600 ∗ cohesiveness − 1.255 ∗ adhesiveness + 0.048 ∗ hardness − 506.31 ∗ springiness (R² = 0.745, p < 0.00005). Simple linear regression analysis showed significant coefficients of determination between BS (R² = 0.586, p < 0.0001) versus folding test grade (FG) and EF versus FG (R² = 0.564, p < 0.0001).     

Stabilization of oil-in-water emulsions by enzyme catalyzed oxidative gelation of sugar beet pectin

Enzyme catalyzed oxidative cross-linking of feruloyl groups can promote gelation of sugar beet pectin (SBP). It is uncertain how the enzyme kinetics of this cross-linking reaction are affected in emulsion systems and whether the gelation affects emulsion stability. In this study, SBP (2.5% w/v) was mixed into an oil-in-water emulsion system (4.4% w/w oil, 0.22% w/w whey protein, pH 4.5). Two separate, identically composed, emulsion systems were prepared by different methods of preparation. The emulsions prepared separately and subsequently mixed with SBP (referred as Mix A) produced significantly larger average particle sizes than the emulsions in which the SBP was homogenized into the emulsion system during emulsion preparation (referred as Mix B). Mix B type emulsions were stable. Enzyme catalyzed oxidative gelation of SBP helped stabilize the emulsions in Mix A. The kinetics of the enzyme catalyzed oxidative gelation of SBP was evaluated by small angle oscillatory measurements for horseradish peroxidase (HRP) (EC 1.11.1.7) and laccase (EC 1.10.3.2) catalysis, respectively. HRP catalyzed gelation rates, determined from the slopes of the increase of elastic modulus (G′) with time, were higher (P < 0.05) than the corresponding laccase catalyzed rates, but the final G′ values were higher for laccase catalyzed gels, regardless of the presence of emulsions or type of emulsion preparation (Mix A or Mix B). For both enzymes, rates of gelation in Mix A were higher (P < 0.05) than in Mix B, and higher stress was needed to break the gels in Mix A than in Mix B at similar enzyme dosage levels. These differences may be related to a lower availability of the feruloyl groups for cross-linking when the SBP was homogenized into the emulsion system during preparation.     

The effects of different levels of non-fat dry milk and whey powder on emulsion capacity and stability of beef, turkey and chicken meats

The effects of different concentrations (0.00, 0.25, 0.50%) of either non‐fat dry milk (NFDM) or whey powder (WP) on emulsion capacity (EC) and emulsion stability (ES) of beef, chicken and turkey meats were studied by using a computer model system. The effects of meats types and additives (NFDM and WP) on EC and ES were found to be statistically significant (P < 0.01). Of the meats, chicken had the highest and beef the lowest values of EC and ES. When using different concentrations of WP and NFDM, 0.25% WP and 0.50% NFDM had the highest values of EC. The effect of different concentrations (0.25 and 0.50%) of WP was insignificant on ES; however, the effects of different concentrations (0.0, 0.25 and 0.50%) of NFDM were significant on ES.     

Effect of stunning systems on meat quality of Manchego suckling lamb packed under modified atmospheres

The effects of the type of stunning (TS) [electrically vs. gas] and packing in modified atmospheres (MA) [MA-A: 30% CO₂/70% O₂; MA-B: 30% CO₂/69.3% N₂/0.7% CO; MA-C: 40% CO₂/60% N₂] on meat quality (pH), drip losses (DL), water holding capacity (WHC), shear force (SF) and instrumental colour (L^∗, and C^∗chroma) of suckling lamb of the Spanish Manchego breed at 7, 14 and 21 d post-packing was studied. Acceptance of meat samples (on the basis of colour and odour) was determined. In general neither the TS nor the MA affected the pH values. Meat from the gas stunned lambs had the lowest DL (P < 0.001 at 14 d post-packing), but lower WHC (more water expelled; P < 0.01 at 14 and 21 d post-packing), was more tender (P < 0.01) and had higher L^∗ (P < 0.001 at 14 d post-packing) and C^∗ values (P < 0.001) than the electrically stunned group. Similar values of WHC and SF were observed for all MA types but the use of CO in the packs (MA-B) caused less DL, gave the highest C^∗ values, acceptability and colour stability with time of storage.     

Texture,colour and sensory evaluation of a conventionally and ohmically cooked meat emulsion batter

Samples of meat emulsion batter were steam or ohmically cooked (at voltage densities ranging from 3 to 7 V cm^?1) to standardized cook values (C_s) or to target end point temperatures (EPT). Higher ohmic voltage densities produced faster heating rates. Texture profile analysis (TPA) of ohmic and steam‐cooked frankfurters showed no significant difference (p ≥ 0.05) in any of the attributes assessed with the exception of springiness, which was significantly lower (p < 0.05) in ohmically cooked samples heated to similar C_s values, although this trend was less pronounced in samples cooked to similar EPT. Instrumental colour evaluations revealed that ohmically cooked samples (cooked both to similar C_s and EPT) differed from steam‐cooked in both a* and hue angle values (especially at 5–7 V cm^?1 (p < 0.05)). Although instrumental measurements revealed differences in selected texture and colour attributes, panellists were not able to distinguish between steam and similar EPT ohmically cooked samples (p < 0.05). Thus while subtle differences may exist in the eating quality of ohmic and steam‐cooked emulsions, these differences are unlikely to be of an order of magnitude to affect consumer acceptance of ohmically cooked meat emulsion products. Copyright © 2004 Society of Chemical Industry