Effect of Steam-Assisted Hybrid Cooking on Textural Quality Characteristics,Cooking Loss,and Free Moisture Content of Beef

Semitendinosus muscles were cooked in a steam-assisted hybrid oven and also convection ovens at three different oven temperatures (180, 210, and 240°C) until three different end point temperatures [65°C (medium-rare), 72°C (medium), 80°C (medium-well)] were reached. Textural properties of cooked beef were investigated by the Warner Bratzler shear test and texture profile analysis. Cooking loss and free moisture content of muscle tissue was determined for each cooking condition. In addition, sensory analysis was carried out in order to compare with the instrumental results and correlations between instrumental texture parameters and sensory results. Steam-assisted hybrid oven cooking of beef resulted in a tougher texture, higher cooking loss, and lower free moisture content than convection cooking. High correlation coefficients (r² > 0.70) were observed between instrumental texture measurements and sensory results for all ovens, especially in terms of tenderness. The free moisture content and adhesiveness values were also correlated well with juiciness (r² > 0.70) for all oven types.     

Ohmic cooking of whole beef muscle — Evaluation of the impact of a novel rapid ohmic cooking method on product quality

Cylindrical cores of beef semitendinosus (500 g) were cooked in a combined ohmic/convection heating system to low (72 °C, LTLT) and high (95 °C, HTST) target end-point temperatures. A control was also cooked to an end-point temperature of 72 °C at the coldest point. Microbial challenge studies on a model meat matrix confirmed product safety. Hunter L-values showed that ohmically heated meat had significantly (p < 0.05) lighter surface-colours (63.05 (LTLT) and 62.26 (HTST)) relative to the control (56.85). No significant texture differences (p ≥ 0.05) were suggested by Warner–Bratzler peak load values (34.09, 36.37 vs. 35.19 N). Cook loss was significantly (p < 0.05) lower for LTLT samples (29.3%) compared to the other meats (36.3 and 33.8%). Sensory studies largely confirmed these observations. Cook values were lower for LTLT (3.05) while HTST and the control were more comparable (6.09 and 7.71, respectively). These results demonstrate considerable potential for this application of ohmic heating for whole meats.     

Effect of radio frequency (RF) heating on the texture,colour and sensory properties of a comminuted pork meat product

Radio frequency (RF) cooking is a form of dielectric heating in which products are heated by subjecting them to an alternating electromagnetic field between two parallel electrodes. Although similar in some respects to Microwave heating, RF has been proposed to be more suitable for industrial heating of meats because of the greater penetration depths possible with this technology. In this study an RF cooking protocol was developed and its effect on selected quality attributes of pork based white pudding was examined. Whilst cooking of the product in air proved unfeasible due to arcing, use of a polyethylene cell with circulating hot water (80 °C) facilitated successful heating of the product. Application of RF using an optimised cooking protocol (RF power = 450 W, cell volume = 500 ml and continuous circulation) resulted in a mean end-point temperature of 73 °C after 7 min 40 s. Similar mean end-point temperatures in water bath and steam oven heated products were achieved after 29 and 33 min, respectively. A factorial experiment was conducted to assess selected quality attributes of the cooked puddings. Results show that RF heated puddings were not significantly different (P > 0.05) from water bath and steam oven heated products with regard to instrumental colour, instrumental texture (Kramer shear and texture profile analysis) and expressible fluid. Furthermore, results of a sensory similarity test involving 60 panellists indicated that panellists were not able to detect differences between puddings cooked by RF and conventional methods. Overall this suggests that RF heating technology could have potential in pasteurisation of meat products though further work is needed to verify this.     

Precision in the measurement of meat texture

The relationships between the level of precision, the variability within muscles and the number of measurements required to assess toughness were quantified in an attempt to rationalise the measurement of meat texture. Variability within M. longissimus dorsi was higher than in other hindquarter muscles of lamb and beef and was less in pork than in beef or lamb. Ten replicate determinations on lamb and beef and seven on pork M. longissimus dorsi would be suited to research work. Under these conditions, 95% of values for each muscle would lie within one-sixth of the texture scale from the mean for 85% of muscles and would lie within one-tenth of the texture scale from the mean for 50% of muscles.     

Prediction of beef eating quality from colour,marbling and wavelet texture features

Beef longissimus dorsi colour, marbling fat and surface texture are long established properties that are used in some countries by expert graders to classify beef carcasses, with subjective and inconsistent decision. As a computer vision system can deliver objective and consistent decisions rapidly and is capable of handling a greater variety of image features, attempts have been made to develop computerised predictions of eating quality based on these and other properties but have failed to adequately model the variation in eating quality. Therefore, in this study, examination of the ribeye at high magnification and consideration of a broad range of colour and marbling fat features was used to attempt to provide better information on beef eating quality. Wavelets were used to describe the image texture of the beef surface at high magnification rather than classical methods such as run lengths, difference histograms and co-occurrence matrices. Sensory panel and Instron analyses were performed on duplicate steaks to measure the quality of the beef. Using the classical statistical method of partial least squares regression (PLSR) it was possible to model a very high proportion of the variation in eating quality (r² = 0.88 for sensory overall acceptability and r² = 0.85 for 7-day WBS). Addition of non-linear texture terms to the models gave some improvements.     

Effects of dry,vacuum, and special bag aging; USDA quality grade; and end-point temperature on yields and eating quality of beef Longissimus lumborum steaks

This study evaluated the effects of three aging methods: (dry (D), wet (W), and special bag (SB)); two quality grades [USDA Choice((≥ Small⁵⁰ marbling) and Select); and two cooked end-point temperatures (62.8 °C and 71.1 °C) on physico-chemical traits of instrumental tenderness, color, and sensory properties of Longissimus lumborum beef muscle. Dry-aged loins had higher (P < 0.0001) weight loss than W or SB aged loins. However, D and SB aged loins had similar (P > 0.05) combined losses. W aged loins had higher (P < 0.01) L* values than D or SB aged loins. Warner–Bratzler shear force of steaks was not affected (P > 0.05) by aging method or quality grade but increased (P < 0.0001) as end-point temperature increased. Sensory panel evaluation also showed no effect (P > 0.05) of aging method or quality grade on myofibrillar tenderness, juiciness, connective tissue amount, overall tenderness or off flavor intensity. Steaks cooked to 62.8 °C were juicier (P < 0.05) than those cooked to 71.1 °C. Neither D nor SB aging had advantages over W aging.     

Prediction of beef eating quality from colour, marbling and wavelet texture features

Beef longissimus dorsi colour, marbling fat and surface texture are long established properties that are used in some countries by expert graders to classify beef carcasses, with subjective and inconsistent decision. As a computer vision system can deliver objective and consistent decisions rapidly and is capable of handling a greater variety of image features, attempts have been made to develop computerised predictions of eating quality based on these and other properties but have failed to adequately model the variation in eating quality. Therefore, in this study, examination of the ribeye at high magnification and consideration of a broad range of colour and marbling fat features was used to attempt to provide better information on beef eating quality. Wavelets were used to describe the image texture of the beef surface at high magnification rather than classical methods such as run lengths, difference histograms and co-occurrence matrices. Sensory panel and Instron analyses were performed on duplicate steaks to measure the quality of the beef. Using the classical statistical method of partial least squares regression (PLSR) it was possible to model a very high proportion of the variation in eating quality (r² = 0.88 for sensory overall acceptability and r² = 0.85 for 7-day WBS). Addition of non-linear texture terms to the models gave some improvements.     

Comparison of instrumental and sensory evaluation of texture of cured and cooked beef meat

The instrumental and sensory texture attributes of beef muscles (M. longissimus dorsi and M. semimembranosus) were compared after curing and thermal treatments. Shear, compression and puncture tests were carried out with an UTM Instron 4301 and the sensory evaluation was made with the score method. The force values obtained for puncture test gave a greater degree of correlation with the sensory tenderness, hardness and elasticity than the shear test forces. The shear test forces were found to significantly correlate with sensory tenderness only for muscles with perpendicular orientation of fibres to the direction of shear blade movement. The evaluation of beef texture with compression test was dependent on the level of sample deformation degree. The force values of compression were found to correlate significantly with elasticity and juiciness of meat up to 60% deformation levels, but at deformation levels higher than 60% appeared significant correlation with tenderness and hardness. The obtained results showed the usefulness of puncture test with proposed parameters for the instrumental measurements of beef texture.     

Prediction of beef palatability from colour,marbling and surface texture features of longissimus dorsi

The palatability of beef has been investigated with digital imaging systems on numerous previous occasions. In the current study, a novel approach was applied using high magnification imaging to develop surface texture features and an alternative colour space greyscale to express muscle surface texture. An automatic segmentation method was applied to develop colour and marbling features and best regression model subsets were selected automatically with genetic algorithms. Results indicated that accurate modelling of beef acceptability with regression models was possible with r² up to 0.95. Modelling of acceptability using high magnification images proved more successful than modelling with low magnification images. Linear models performed well compared to non-linear models. Other sensory measurements particularly TPA hardness were more difficult to model, although an accurate model of juiciness was developed. Addition of non-linear terms did not give large improvements except for juiciness.     

Comparison of the predictive power of beef surface wavelet texture features at high and low magnification

Beef longissimus dorsi surface texture is an indicator used in predicting beef palatability by expert graders. Computer vision systems have previously used imaging at normal view to develop surface texture features with some success. Good models of beef overall acceptability using imaging at high magnification have been recently developed. As a comparison the same surface texture features were computed from the corresponding images at normal view and used to model overall acceptability. Both sets of texture features were also combined with muscle colour and marbling features and used to model overall acceptability. Models using texture features alone were more successful at normal modality. However colour and marbling features combined much better with texture features at high modality to yield the most accurate model of overall acceptability (r² = 0.93). Accurate Partial Least Squares Regression (PLSR) models were computed at both modalities with and without inclusion of colour and marbling features. Addition of squared terms to the models failed to improve accuracy.     

Quality properties of wine from Korean kiwifruit new cultivars

Several domestic varieties of kiwifruit including Actinidia deliciosa cv. ‘Hayward’, ‘Daeheung’, ‘Monty’, ‘Arimold’, ‘Jinmi’, ‘Hyangrok’ and A. chinensis cv. ‘Haenam’ and ‘Golden King’ were utilized for the processing of wines. Kiwifruit wines were analyzed for sugar content, alcohol, acidity, pH, color, total phenols and antioxidant activity by radical scavenging assay ABTS. The soluble solid content of the kiwifruit must ranged between 22 and 25% and then was fermented at 14 °C during 4 months. The amount of alcohol productions differed especially during the first week of fermentation. Among cultivars, ‘Haenam’ and ‘Arimold’ were relatively slower than other wines with regard to alcohol production rate. The yield of wine production was increased from 63.35% to 66.19% in weight by using processing with pectinase.The ‘L’ values of wine made from ‘Hayward’ and ‘Monty’ were lower and darker than those of wines prepared from other cultivars. Wine made from ‘Daeheung’ had total phenols of 790 mg L⁻¹, which was the highest among wines, followed by ‘Haenam’ and ‘Golden King’. ‘Daeheung’ also showed the highest antioxidant activity (22.55 mM TE L⁻¹), while ‘Arimold’ showed the lowest one (10.91 mM TE L⁻¹). The mean overall acceptability scores among kiwifruit wines ranged between 3.8 and 4.5. The sensory evaluations were higher in ‘Golden King’, ‘Monty’, ‘Daeheung’, ‘Arimold’, and ‘Hayward’ than those of ‘Haenam’, ‘Jinmi’, and ‘Hyangrok’. However, for commercial kiwifruit wine production not only overall sensory acceptance, but also functional properties such as total phenols and antioxidant activity, and fruit cultivation volume should be concerned. Therefore, three of kiwifruit cultivars which are ‘Golden King’, ‘Daeheung’, and ‘Hayward’ had the most desirable characteristics suitable for kiwifruit wine production.     

LOW-FAT, NO ADDED SALT IN RESTRUCTURED BEEF STEAKS WITH VARIOUS BINDERS

This research investigated technology for the development of a low-fat restructured beef steak devoid of added salt with texture similar to intact muscle. Low-fat (10%), low-sodium restructured beef steaks made from closely trimmed, flaked beef round muscles and tumbled with or without a binding agent were compared to boneless top loin steaks (5–6% fat). Boneless top loin steaks had greater (P < .05) shear resistance, cohesiveness, juiciness, overall desirability, percentage moisture (raw) and percentage protein (cooked) than restructured steaks. Steaks made with 3.0% modified potato starch had slightly more juiciness and moisture content (cooked) and lower expressible fluid content than all other restructured samples. Product made with 1.0% microcrystalline cellulose had lower (P < .05) juiciness scores than top loin steaks and restructured steaks made with no additives or modified potato starch. Use of 0.25% kappa-carrageenan or 1.5% surimi increased (P < .05) sensory scores for off-flavor. Steaks made with 1.5% surimi also had lower (P < .05) sensory scores for overall desirability.     

Effect of End-point Temperature and Degree of Doneness on Sensory and Instrumental Flavor Profile of Beefsteaks

ABSTRACT: Beef M. longissimus thoracis et lumborum was used to investigate the effects of 6 end-point temperatures on flavor and texture. Steaks cooked to medium temperature were associated with 4-heptanolide, whereas those cooked to higher temperatures were associated with pyrazines and hexanol. These steaks were also associated with flavor attributes, such as roasted, burnt, and beefy. However, consumers did not find differences in flavor liking of steaks (P > 0.05) cooked to 6 end-point temperatures. Although steaks cooked to lower temperatures were liked for their tenderness and juiciness, overall liking scores were not affected by end-point temperature. Thus both flavor and tenderness play an important role in consumer satisfaction.     

Oxidative Stability and Textural Quality of Restructured Beef Roasts as Affected by End-point Cooking Temperatures, Storage and the Incorporation of Surimi

Restructured beef roasts containing either 0 or 3.5% surimi were cooked to end-point internal temperatures of 50, 60, and 70°C to assess treatment effects on textural and oxidative quality after 2 and 5 days of refrigerated (4°C) storage. Surimi did not improve binding, cook yield or sensory tenderness and juiciness. The sensory panel was able to distinguish a slightly more pronounced fishy flavor when surimi was added. End-point internal temperature had no effect on tensile strength, however, tenderness increased and juiciness decreased with increased endpoint temperatures. Higher end-point internal temperature enhanced lipid oxidation, which proceeded more rapidly during refrigerated (4°C) storage. Nonheme iron increased with increasing end-point temperature. During storage, phospholipid content decreased while total lipid remained constant.     

Effect of post-rigor muscle length on the texture of meat

Pre-rigor samples of beef M. sternomandibularis were allowed to pass into rigor in both lengthened and shortened states. After ageing, half of the samples from each group were stretched, the other half acting as control. The strength of the raw and heated meats was determined by a shear test. The strength of the raw meat increased in proportion to the muscle length, irrespective of when the length was altered. The strength was due mainly to the connective tissue elements. After heating, the shortened samples were tougher than the lengthened ones; stretching the muscles post-rigor tenderised the shortened samples but not the lengthened ones. These results indicate that the texture of cooked meat was dependent on the interaction of actomyosin and connective tissue components of muscle.