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Abstracts
Objectives: The utilization of the Maillard reaction (glycation) to produce food flavorings and taste enhancers is widely documented. Designed cocktails containing reducing monosaccharides, amino acids and peptides are reacted at specific temperatures to obtain a desired meat flavour. This study was conducted to investigate the perceived saltiness and savoriness of poultry protein hydrolysate glycated at moderate temperatures with glucosamine (GlcN), a reactive amino sugar obtained from the hydrolysis of chitin. Materials and Methods: Poultry protein (PPI) was isolated from the mechanically deboned turkey meat with the acid-aided isoelectric solubilization and precipitation process. The PPI was then hydrolyzed with Alcalase (enzyme:PPI = 1:10 v/w, pH 8, 50 °C, 3.5 h) and it was pooled and treated as a hydrolysate stock solution. The hydrolysate was glycated with GlcN (GlcN:hydrolysate = 1:4 w/w, pH 7.0-7.5, 3.5 h) at moderate temperatures (37 °C, 50 °C, respectively) in the presence (+) or absence (-) of transglutaminase (TGase); the process was replicated in three batches and pooled according to the respective sample treatment. Each of the glycated samples was compared against controls (native hydrolysate, GlcN and sodium solution, respectively) and commercial taste enhancers (Table 1) in two separate sessions of sensory evaluation held on two different days. A randomized complete design was used with sample treatment as experimental unit. In the first session of sensory evaluation, 64 consumers were asked to rank the saltiness intensity of the 10 samples served randomly; another 61 consumers were recruited in the second session to rank the savory intensity. Sample with the highest intensity was ranked with score 1 whilst score 10 was given to sample with the lowest intensity. All the mean rank scores were analyzed with Friedman's test and separated with Bonferroni adjustment. Means were considered statistically significant at p ≤ 0.05. Results: All the glycated PPI hydrolysates showed enhanced saltiness compared to the salty solution (p b 0.05). Remarkable, PPI hydrolysate glycated at 37 °C in the absence of TGase showed a higher perceived saltiness compared to the commercial taste enhancers (p b 0.05). A tendency towards significance in the perceived savory taste (p = 0.059) as a function of the treatments was also observed. T5:1 T5:2 T5:3
Table 1 Statistical analysis of sensory evaluation. Treatments
T5:4 T5:5 T5:6 T5:7 T5:8 T5:9 T5:10 T5:11 T5:12 T5:13 T5:14 T5:15 T5:16 T5:17
Hydrolysate 37 °C Hydrolysate 50 °C Glycated hydrolysate 37 °C(-TGase) Glycated hydrolysate 37 °C(+ TGase) Glycated hydrolysate 50 °C(-TGase) Glucosamine 50 °C Salty solution (Sodium) Savory solution (Sodium + Monosodium glutamate) Kokumi solution (Sodium + Glutathione) Savory + Kokumi solution (Sodium + Monosodium glutamate + Glutathione) P value
Mean Rank Scores Salty (N = 64)
Savory (N = 61)
4.8 abc 4.9 abcd 4.5 a 4.7 ab 4.9 abc 5.9 bcd 6.5 d 6.4 cd
6.3 6.0 5.1 5.0 4.8 5.3 5.8 6.2
6.2 bcd 6.2 bcd
5.4 5.2
b0.001
0.0593
Low mean rank scores denote a higher perceived taste intensity. Mean rank scores with different letters within the same column were significantly different (p b 0.05). Conclusion: In conclusion, this study was able to demonstrate that the glycated hydrolyzed PPI possessed salt-enhancing properties. This study can benefit the salt reduction strategy in the meat industry through the addition of Alcalase hydrolyzed PPI and GlcN. Keywords: glucosamine, glycation, poultry protein isolate, salty, savory doi:10.1016/j.meatsci.2015.08.064
Meat and Poultry Processing, Ingredient Technology and Packaging 42 Effect of various drying temperatures of oven-drying on physicochemical properties and antioxidant activity of pork patties during refrigerated storage H. Kim⁎, K.B. Chin, Animal Science and Functional Food Research Center, Chonnam National University, Buk-gu, Republic of Korea Objectives: This study was performed to evaluate physicochemical properties and antioxidant activity of pork patties with ovendried tomato powders as affected by different drying temperatures. Materials and Methods: Fresh tomatoes were homogenized by food mixer and then, dried at 60, 80 and 100 °C in an oven. Control patties without dried tomato powder (DTP), reference patties with 0.1% of ascorbic acid (REF), and treatment patties with 1% powder of DTP in a 60 (TRT1), 80 (TRT2) and 100 °C (TRT3) oven-drying were manufactured. The patties were packaged using a polystyrene case and stored at 4 °C. During storage, patties were analyzed at 0, 3, 7 and 14 days of refrigerated storage. pH, Hunter color values, lipid oxidation (2-thiobarbituric acid reactive substances, TBARS, malondialdehyde (MDA) mg/kg); peroxide value, POV), protein deterioration (volatile basic nitrogen, VBN, mg%) and microbial counts (total bacterial count, TPC; Enterobacteriaceae count, VRB, log cfu/g) of pork patties were measured during 14 days of refrigerated storage. Data were analyzed using SPSS 21.0 program. Two-way analysis of variance was performed as factors for treatment and storage time. Significant differences among the means of treatments were analyzed by Duncan’s multiple range test (P b 0.05). Results: Addition of 1% DTP decreased pH values of pork patties (P b 0.05). Among the treatments, patties with 1% of DTP from 100 °C oven-drying showed the lowest lightness value (P b 0.05). In contrast, incorporation of DTP into patties increased redness and yellowness values (P b 0.05). TBARS values of treatments were lower than those of control, but higher than those of REF until 7 days of storage (P b 0.05). POV values of patties with DTP with various drying temperatures showed lower than those of control until the end of storage time (P b 0.05). Patties with DTP with different drying temperatures were lower VBN than those of CTL. However, no antimicrobial activity was observed among the treatments (P N 0.05). Conclusion: These results suggested that DTP could be used as a natural antioxidant in meat products during refrigerated storage.
Keywords: antioxidant activity, drying temperatures, pork patty, tomato doi:10.1016/j.meatsci.2015.08.065
Meat and Poultry Processing, Ingredient Technology and Packaging 44 Retail shelf-life of fresh and cured meat products stored under fluorescent and light emitting diode (LED) illumination sources A. Lowder⁎, J. Killefer, Animal & Rangeland Sciences, OR State University, Corvallis, United States Objectives: Illumination emission spectrum and intensity are both known factors affecting the retail shelf-life of fresh and nitrite cured meat products. In fresh products, greater overall light intensity and increased interaction with certain wavelengths of light will speed the oxy- to metmyoglobin conversion and prematurely bring about discoloration that consumers select against at retail. The same factors in nitrite cured products hasten fading of the cured pink color, again causing rejection. As such, it is important to meat shelf life to consider lighting type, which determines emission spectrum, where meat products may be exposed to light for extended periods of time, such as grocery outlets. Currently, fluorescent lighting is
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heavily used in retail due to advantages in efficiency and longevity over older lighting types. However, the newer technology of light emitting diode (LED) sources has recently achieved commercial viability. As LED holds major advantages over fluorescent in energy efficiency, longevity and environmental friendliness, their adoption by many commercial retailers is inevitable. The current study sought to determine what impact, if any, LED lamps may have on fresh and nitrite cured meat products relative to fluorescent lamps. Materials and Methods: Beef steaks were sliced to 2.54 cm thick from semitendinosus and overwrapped in O2 permeable film on polystyrene trays. Cured beef sausages were manufactured in a table top bowl chopper from round muscles (4-6% fat) with 2% added salt, 10% added water and 156 ppm sodium nitrite. Sausage samples (~100 g) were placed in a vacuum package and flattened to 6 mm before sealing and cooking in a water bath to 71 °C. Packaged steaks and sausages were placed into a simulated retail display (4 °C) with either fluorescent or LED illumination; a control group was kept in dark storage. Both illumination sources were rated at 3500 K color temperature and light intensity was normalized to 1600-2200 lux. Instrumental color (400-700 nm reflectance spectra) was monitored daily and lipid oxidation at certain intervals was determined by thiobarbituric acid reactive substances (TBARS). Both studies were replicated three times. Results: Spectra of both light sources showed heaviest emissions in the visible range (400-700 nm) with the fluorescents emitting some in the infrared range (N700 nm) as well. As such, the surface temperature of the fluorescent samples was 0.5 – 1.0 °C greater than those under LED. This did not negatively affect shelf life of fresh beef steaks as there were no statistically significant differences in measured parameters (L*, a*, b* or 630/580 nm ratio). Cured sausages, however, experienced marked decline in red color as determined by a* values when under LED light for at least 16 d as compared to fluorescent light and dark storage. Lipid oxidation (TBARS) and cured color intensity (650/570 nm ratio) were not different on any testing day between the light sources for cured sausage. Conclusion: In this study, it was observed that the redness of cured sausage declined faster under LED lighting than fluorescent but no other indicator of shelf-life was affected, while fresh beef steak shelf-life was unaffected by lighting type. Differential sensitivity to certain wavelengths may explain the dichotomy. Retailers eyeing adoption of LED should consider product type (cured vs uncured) and the specific emission spectra of the light source.
Materials and Methods: Nine batches of ground turkey were used to manufacture the polyphosphate treatments (3 unencapsulated polyphosphates; 3 encapsulated polyphosphates, each at two TRP). Regardless of being encapsulated or unencapsulated, 0.4% pure polyphosphate along with 10% water and 1% salt were delivered on a meat weight basis. Polyphosphates (PP) were commercially encapsulated with hydrogenated vegetable oil designed to achieve the two different temperature release points. Treated ground turkey was stuffed into plastic sausage casings (7.4 cm diameter). After pre-cook storage, samples were water cooked. The encapsulated polyphosphates were coded as eHMP-60, eHMP-68, eSPP-60, eSPP-68, eSTP-60, and eSTP-68. Unencapsulated polyphosphates were coded as uHMP, uSPP, and uSTP. Dependent variables determined on cooked samples included: pH, soluble orthophosphate (SOP; hydrolysis of PP), lipid hydroperoxides (LPH), and thiobarbituric acid reactive substances (TBARS). Statistical analysis was first performed to determine the most effective TRP (based on limiting PP hydrolysis and lipid oxidation), after which those encapsulated polyphosphates were compared to unencapsulated cohorts. Results: TRP 68 was more effective (P b 0.05) than TRP 60 in limiting polyphosphate hydrolysis only for eSPP (SOP: eSPP-68, 4770 μg/g; eSPP-60, 5076 μg/g). TRP did not influence (P N 0.05) SOP accumulation for eSTP. However, TRP 68 resulted in higher (P b 0.05) SOP for eHMP (eHMP-68, 4814 μg/g; eHMP-60, 4612 μg/g). TRP 68 only influenced (lower, P b 0.05) TBARS for eHMP (eHMP-68, 0.49 mg/kg; eHMP-60, 0.62 mg/kg). At a given TRP, eSPP and eSTP were equally more effective at reducing TBARS (P b 0.05; 55% at TRP 60, 48% at TRP 68, respectively) in comparison to eHMP. The difference in the pH between the two sets of turkey breasts had minimal effect on control of lipid oxidation by the encapsulated phosphates likely because the phosphates altered the pH upon cooking. Only a minor difference of about 0.05 of a pH unit was found in the cooked samples between the high pH group and low pH group. At the end of post-cooked storage (day 7) TRP 68 encapsulated PP had about 5 times lower (P b 0.05) LHP than unencapsulated PP (600 versus 2991, μmol/kg). eSTP-68 and eSPP-68 were more effective at limiting TBARS accumulation than e-HMP-68 and both had about 4 times lower TBARS than unencapsulated cohorts. Conclusion: Encapsulating polyphosphates dramatically preserve their antioxidant functionality by limiting their exposure to active phosphatases prior to thermal processing. The higher temperature release point associated with the melting properties of the encapsulate likely provided the opportunity for more complete inactivation of the phosphatases prior to releasing the polyphosphate.
Keywords: Color stability, Lighting, Shelf-life
Keywords: encapsulated polyphosphates, lipid oxidation, turkey
doi:10.1016/j.meatsci.2015.08.066
doi:10.1016/j.meatsci.2015.08.067
Meat and Poultry Processing, Ingredient Technology and Packaging 45 Inhibition of lipid oxidation in ground turkey breasts by encapsulated Polyphosphates as influenced by postmortem pH J. Clausa,⁎, C. Dua, B. Kılıçb, aAnimal Sciences, Univerisity of WI, Madison, United States, bDepartment of Food Engineering, Suleyman Demirel University, Isparta, Turkey
Meat and Poultry Processing, Ingredient Technology and Packaging 46 Dry potato extract improves water holding capacity, shelf life, and sensory characteristics of beef patties M. Colle⁎, R.P. Richard, M.J. Colle, W.I. Loucks, S.J. Gray, Z.J. Reynolds, H.A. Sutton, J.A. Nasados, M.E. Doumit, Animal and Veterinary Science, University of ID, Moscow, United States
Objectives: The objective of this research was to determine polyphosphate antioxidant abilities as influenced by meat pH (high, 6.4 to 6.7; low: 5.9 to 6.2), polyphosphate type (HMP = sodium hexameta phosphate, SPP = sodium acid pyrophosphate, STP = sodium tripolyphosphate), encapsulation (u = unencapsulated, e = encapsulated) and two different temperature release points (TRP: 60 and 68 C), by a replicated (n = 3) experiment using ground turkey breasts associated with pre-cook storage times (3, 6, 24 h), end-point cooking temperatures (73.9 C, 79.4 C) and post-cook storage times (0, 1, 7 d).
Objectives: Binders are commonly incorporated into processed meat products to improve product yield, texture, and palatability. Our objective was to examine shelf stability, cooked product yield, and sensory characteristics of beef patties with no added binder (Control), soy flour (TVP), or dry potato extracts. Materials and Methods: Potato extracts were provided by Basic American Foods (Blackfoot, ID) and included X-TEND™, X-TEND™ M, which is a potato extract containing mustard, and X-TEND™ S, which includes sodium acid pyrophosphate. USDA Choice beef shoulder clods