Are muscle fiber types different between normal and dark-cutting beef?

Muscle fiber (MF) characteristics of Longissimus thoracis (LT) muscles from heifer (n = 11) and steer (n = 12) carcasses graded Canada AA (AA, normal, n = 4/sex) or dark-cutting (Canada B4) were examined and related to beef quality. Atypical (AB4, pH < 5.9, n = 4/sex) and typical (TB4, pH > 5.9, n = 3 and 4 for heifers and steers, respectively) dark-cutting carcasses were represented. Muscle fiber type proportions did not differ between AA, AB4 and TB4 muscles, although type I and IIB muscle fiber diameters were greater in TB4 than in AA LT. That AB4 muscle fiber proportions were not different from AA and TB4 muscles suggests that the increased MF diameter of TB4 muscle was due to water retained by muscle proteins at high ultimate pH, as evidenced by decreased cooking loss. Dark-cutting was therefore unrelated to muscle fiber proportions, and increased Type I and IIB diameters in dark cutting LT were likely driven by elevated intramuscular ultimate pH.

Investigating the Effect of Probiotics as Natural Preservatives on the Microbial and Physicochemical Properties of Yogurt-Marinated Chicken Fillets

Microbial flora of probiotic yogurt can have nutraceutical properties and improve beneficial health effects of food products. In this study, microbial and physicochemical properties of raw chicken fillets dipped in regular yogurt and probiotic yogurt containing Lactobacillus casei, preserved at 4°C for 9 days, were studied. In this regard, microbial analysis (Staphylococcus aureus, fecal coliform, yeasts, and molds) and physicochemical analysis (pH, water holding capacity, cooking loss percentage, Thiobarbituric acid reactive substances, and texture profile analysis) were performed during the storage time. In comparison with control samples, the amount of Staphylococcus aureus, fecal coliforms, yeast and mold counts, pH index, malondialdehyde value, and cooking loss percentage reduced significantly ( P < 0.05 ) in the chicken fillets treated with regular and probiotic yogurt, while the water holding capacity increased in six days. It was concluded that probiotic and regular yogurts reduced microbial growth and improved the physicochemical quality of chicken fillets during storage and cooking time.

Effect of Packaging Type and Aging on the Meat Quality Characteristics of Water Buffalo Bulls

The present study determined the effect of the packaging type and aging time on the meat quality of water buffalo (Bubalus bubalis) bulls. A total of n = 36 longissimus lumborum (LL) muscles from n = 18 buffalo bulls were obtained. Half LL muscles were packed in modified atmosphere packaging (Hi-O2 MAP), vacuum packaging (VP), and oxygen-permeable packaging (OP) on day 1, while the other half were aged for 7 days. Meat instrumental color, cooking loss, Warner–Bratzler shear force (WBSF), thiobarbituric acid reactive substances (TBARS), and total volatile basic nitrogen (TVB-N) of the LL steaks were analyzed, both on unaged and aged buffalo meat. Color CIE L* and C* values on all display days and a* on the first 4 days of the simulated retail display under Hi-O2 MAP packaging were significantly higher than those of the VP and OP. WBSF and TBARS values were also higher under Hi-O2 MAP as compared to the other packaging. Steaks under OP exhibited lower cooking loss but higher TVB-N values than the MAP and VP. The 7-day-aged buffalo meat indicated higher instrumental color (L*, a* and C*), cooking loss, and lower WBSF values than fresh meat. This study concluded that Hi-O2 MAP improved the color; however, it negatively influenced the buffalo meat’s WBSF and TBAR values. Furthermore, VP and aging were the most effective in decreasing the WBSF values of buffalo meat.

Relationship between Inherent Cooking Rate and Warner-Bratzler Shear Force of Pork Chops Cooked to Two Degrees of Doneness

The objective was to test inherent cooking rate differences on tenderness values of boneless pork chops when exogenous factors known to influence cooking rate were controlled. Temperature and elapsed time were monitored during cooking for all chops. Cooking rate was calculated as the change in °C per minute of cooking time. Warner-Bratzler shear force (WBSF) was measured on chops cooked to either 63 °C or 71 °C. Slopes of regression lines and coefficients of determination between cooking rate and tenderness values for both degrees of doneness (DoD) were calculated. Shear force values decreased as cooking rate increased regardless of DoD (p ≤ 0.05), however changes in tenderness due to increased cooking rate were limited (β1 = −0.201 for 63 °C; β1 = −0.217 for 71 °C). Cooking rate only explained 3.2% and 5.4% of variability in WBSF of chops cooked to 63 °C and 71 °C, respectively. Cooking loss explained the most variability in WBSF regardless of DoD (partial R2 = 0.09–0.12). When all factors were considered, a stepwise regression model explained 20% of WBSF variability of chops cooked to 63 °C and was moderately predictive of WBSF (model R2 = 0.34) for chops cooked to 71 °C. Overall, cooking rate had minimal effect on pork chop tenderness.

Prediction of beef quality traits through mini NIR spectrophotometer and multivariate analyses

The aim of this study was to test the ability of mini NIR reflectance spectroscopy to predict beef quality traits. Sixty M. longissimus thoracis were collected and spectra were obtained prior to beef quality trait analysis. Calibration equations were developed from reference data (n=60) of pH, color traits (lightness, redness and yellowness), drip loss (%), cooking loss (%), CP (%), EE (%), moisture (%), DM (%), and Ash (%) using partial least squares regressions. Predictive ability of the models was assessed by coefficient of determination of cross-validation (R2CV) and root mean square error of cross-validation. Predictions models were satisfactory (R2CV = 0.95) for pH, (R2CV = 0.96) for lightness (L*), (R2CV = 0.96) for redness (a*), (R2CV = 0.97) for yellowness (b*), (R2CV = 0.95) for drip loss, (R2CV = 0.95) for cooking loss, (R2CV = 0.94) for CP, (R2CV = 0.95) for EE, (R2CV = 0.91) for moisture, (R2CV = 0.91) for DM and (R2CV = 0.91) for ash. The ratio performance deviation is 5.35, 5.34, 5.87, 5.16, 4.64, 4.81, 4.45, 4.95, 3.36, 4.73 and 4.47 for L*, a*, b*, pH, drip loss, cooking loss, CP, EE, moisture, DM and Ash respectively which indicates that all values are adequate for analytical purposes. Range error ratio are 20.69, 22.97, 27.11, 18.92, 20.74, 16.20, 17.80, 17.52, 14.96, 17.89 and 17.87 for L*, a*, b*, pH, drip loss, cooking loss, CP, EE, moisture, DM and ash respectively. From the findings of this study it can be concluded that mini NIRS is a suitable tool for a rapid, non-destructive and reliable prediction of beef quality.

Combined effect of irradiation and butylated hydroxyanisole on shelf life and quality of beef at ambient temperature

The study was aimed to evaluate the effect of gamma irradiation and butylated hydroxyanisole (BHA) on meat quality traits and safety of beef. Samples were divided into four treatment groups treated with 0.01% BHA and gamma ray having T0 (Control), T1 (3 kGy), T2 (5 kGy) and T3 (7 kGy), respectively. The analyses were conducted at 0, 3, 5 and 7 days of interval. The study was conducted in completely randomized factorial (CRD) design. Traits evaluated were color value (L*, a*, b*), pH, drip loss, cooking loss, ERV and WHC, DM, moisture, CP, fat, ash, thiobarbituric acid reactive substances (TBARS), peroxide value (POV), free fatty acid (FFA), total coliform count (TCC), total viable count (TVC) and total yeast mould count (TYMC). Color, flavor, tenderness, juiciness and overall acceptability were significantly differed (p<0.01) for days of intervals. Positive and significant interaction (p<0.01) between treatment and days of interval was found for color value (L*, a*, b*), drip loss, cooking loss, ERV, WHC except raw pH. There were found positive and significant interaction (p<0.01) between treatment and days of interval for DM, CP, FFA and TBARS except POV. The TYMC and staphylococcus were significantly decreased (p<0.05) at different treatment groups compared to control group. Salmonella non-significantly (p>0.05) increased and staphylococcus significantly (p<0.01) decreased with increasing irradiated doses in beef. Hence, it may be concluded that BHA treated irradiated beef had a potential effect of shelf life to maintain quality and safety aspect of beef.

Characteristics of Pork Muscles Cooked to Varying End-Point Temperatures

M. biceps femoris (BF), m. semimembranosus (SM) and m. semitendinosus (ST) from fresh pork ham were evaluated for characteristics of quality after cooking to an internal endpoint temperature of 62 °C or 73 °C. Fresh ham muscles from the left side (N = 68) were cut into 2.54 cm thick chops and allocated to cooking loss, Warner–Bratzler shear force (WBSF), pH and instrumental cooked color analysis. Cooking losses were greater (p < 0.0001) for SM and chops cooked to an internal temperature of 73 °C (p < 0.0001), whereas WBSF did not differ (p = 0.2509) among the three muscles, but was greater (p < 0.0001) in chops cooked to 73 °C. Fresh muscle’s pH was greater (p < 0.05) in ST than BF or SM. Lastly, the interactive effect (p < 0.05) of muscle × endpoint temperature for ST chops cooked to 73 °C was lighter (L*), but, when cooked to 62 °C, they were more red (a*), more yellow (b*) and incurred less color change from red to brown than BF or SM. The current results suggest it is plausible for BF, SM and ST to be considered for alternative uses instead of traditional value-added manufacturing.

Advance on the Capitalization of Grape Peels By-Product in Common Wheat Pasta

Capitalization of winery by-products has received high interest among scientists, producers and consumers concerned with healthy diet and environment protection. Grape peels are rich in fiber and polyphenols and can be used as ingredients in pasta matrix in order to increase the nutritional and functional value of such a staple food. The aim of this paper was to investigate the effects of grape peel flour added in various amounts (1–6%) to common wheat pasta dough viscoelasticity and texture and on pasta chemical composition, color, cooking behavior and texture, revealing at the same time the relations between characteristics. Grape peel flour induced the increase of the elastic (G′) and viscous (G″) moduli, dough hardness, springiness, cohesiveness, pasta crude ash, crude fat, crude fiber, total polyphenols and resistant starch contents, pasta water absorption, cooking loss and breaking force as the addition level was higher and compared to the control. On the other hand, dough resilience, pasta luminosity, chewiness and firmness decreased as the amount of grape peel flour raised. Significant correlations (p < 0.05) were obtained between the chemical composition and color parameters, while crude fiber, protein and fat were correlated with dough and pasta texture, total polyphenols with resistant starch content, cooking loss with crude fiber and dough textural parameters. The obtained results underlined the opportunity to use a valuable byproduct such as grape peels in novel pasta formulations, being helpful for processors to extend the product variety and to optimize the processes in order to better satisfy consumer’s demand for functional foods.

Pemberian Tepung Katuk dan Dampaknya Terhadap Parameter Mutu Karkas Ayam Kampung Betina

Penelitian ini bertujuan untuk mengetahui Pemberian Tepung Katuk dan Dampaknya Terhadap Parameter Mutu karkas Ayam Kampung Betina. Penelitian ini dilakukan selama 3 bulan terhitung dari bulan Agustus hingga Oktober 2020 yang berlokasi di Commercial Zone and Animal Laboratory (CZAL) dan Laboratorium Jurusan Peternakan Fakultas Pertanian Universitas Bengkulu. Rancangan penelitian yang digunakan adalah Rancangan Acak Lengkap (RAL), terdiri atas 4 perlakuan dengan 10 ekor ayam kampung betina sebagai ulangan perpelakuan, P0 = 0% tepung daun katuk, P1 = 4% tepung daun katuk, P2 = 8% tepung daun katuk, P3 = 12% tepung daun katuk. Parameter mutu karkas yang diamati pada penelitian ini yaitu bobot potong, bobot karkas,persentase karkas, warna Karkas, meat bone ratio, cooking loss dan drip loss. Hasil yang didapat dalam penelitian menunjukan bahwa pemberian tepung daun katuk berpengaruh tidak nyata terhadap (P>0.05) bobot potong,bobot karkas, persentase karkas, warna karkas, meat bone ratio, cooking loss dan drip loss pada ayam kampung betina. Kesimpulan yang dapat diambil yaitu perlakuan tidak mempengaruhi mutu karkas ayam kampung betina.

Karakteristik Fisikokimia dan Organoleptik Pepes Daging Itik Petelur Afkir yang Dilumuri Bubuk Daun Nangka (Artocarpus heterophyllus)

This study aimed to analyze the physicochemical and organoleptic characteristics of rejected laying duck meat pepes after being coated with jackfruit leaf powder (JLP). The research design employed was a completely randomized design consisting of 4 treatments (P0: without any coating with JLP; P1: 5%; P2: 10%; and P3: 15% smearing of JLP) with 3 replications. The variables measured were cooking loss, water holding capacity (WHC), pH, and water content which were analyzed by Anova and multiple comparisons DMRT by significance level 0.05, and organoleptic which were analyzed by description. The results of the study showed that rejected laying duck meat smeared with JLP had no significant effect (P>0.05) on cooking loss, WHC pH, and moisture content of the pepes. However, the 15% JLP was able to enhance the aroma of the pepes. The average range value of the cooking loss was 14.00 to 15.33%, the WHC was 53.76-55.47%, the pH value was 6.22-6.29%, and the moisture content was 67.83-71,28%. The results of the hedonic quality test showed that the average value of the meat aroma ranged from 4.03-4.20 in the slightly fishy to a very non-fishy category, the interval scale test results showed P0, P1, and P2 in an interval scale of 3.40-4.19 (slightly fishy aroma), different from P3 which is included in the interval scale from 4.20 to 5.00 (very not fishy). The tenderness of the meat was 3.52-3.92 as the tender category, the taste of the meat was 3.88-4.10 as the delicious category. The results of the hedonic test showed that the average value of the aroma of meat ranged from 4.02-4.12, the tenderness from 3.39-3.64, and the taste from 3.88-3.97. All scores were in the liking category. It was concluded that 5% to 15% smearing of JLP did not change the physicochemical properties of rejected layer duck meat paste, but 15% application of it could increase the aroma.