Effects of porcine somatotropin (PST) administration on the fat/lean content and processing properties of pork bellies

Porcine somatotropin (PST)-supplemented pigs were slaughtered at 109 or 131·8 kg; bellies were analyzed for compositional and bacon processing characteristics and compared with bellies from controls (slaughtered at 109 kg). Bellies from control and 109 kg, PST-treated pigs were significantly lighter (P < 0·01) in weight whereas the PST-treated bellies were significantly (P < 0·01) leaner than controls regardless of slaughter weight. The leaner bellies resulted in greater (P < 0·01) brine pickup, reduced smokehouse yields and bacon with less fat regardless of slaughter weight. Frying yield for the bacon from PST-treated pigs was significantly (P < 0·01) higher than that of the controls probably because of the fat/lean difference. The changes observed in bacon from PST-supplemented pigs appear to be due to the compositional change induced by PST administration.     

BELLY THICKNESS EFFECTS ON THE PROXIMATE COMPOSITION, PROCESSING, AND SENSORY CHARACTERISTICS OF BACON

This study was conducted to evaluate the effects of belly thickness on processing, sensory and visual characteristics, moisture and fat of bacon made from 45 bellies of various thicknesses. Belly thickness had a linear effect (P < 0.05) on raw, cured, and cooked weights, and water and fat content. A linear relationship (P < 0.05) was observed between belly thickness and slice integrity, appearance, and lean-to-fat ratio of bacon. Saltiness, texture and mouthfeel, bacon flavor intensity, and off-flavor intensity were unrelated to raw belly thickness.     

Benchmarking value in the pork supply chain: Characterization of US pork in the retail marketplace

Retail pork from eight US cities was obtained for quality and palatability evaluations. Boneless pork loin chops were classified into one of three quality categories - "high," "average," or "low" - with higher quality chops possessing more desirable color, marbling, juiciness, and shear force characteristics than lower quality chops. Loin chops that were enhanced (injected with solution to improve juiciness and/or tenderness) had higher (P<0.05) pH, less purge and cook loss, and higher palatability ratings compared to non-enhanced chops. Hams compared by their protein fat free (PFF) classifications showed that ham and water product received the highest (P<0.05) ratings for juiciness and tenderness, and ham with natural juices received the highest (P<0.05) texture, ham flavor intensity, and smoke flavor ratings. Bacon was compared by price/brand categories; however, the highest priced, national branded bacon (US$12.03/kg) was similar (P>0.05) for most quality and all palatability traits to the lowest priced, national branded bacon (US$6.47/kg) and the store branded bacon (US$8.30/kg) even though retail prices differed widely. Overall, there were tremendous ranges in values for these products indicating that retail pork is quite variable and that efforts to improve the quality and consistency of it must continue.     

Effects of Retail Style or Food Service Style Packaging Type and Storage Time on Sensory Characteristics of Bacon Manufactured from Commercially Sourced Pork Bellies

Objectives were to characterize differences in pork bellies that were stored frozen for different durations prior to processing and characterize sensory properties of the bacon derived from those bellies when stored in either retail or food service style packaging. Bellies (n = 102) were collected from 4 different time periods, fresh bellies (never frozen) and bellies frozen for 2, 5, or 7 mo, and manufactured into bacon under commercial conditions. Food service bacon was packaged in oxygen‐permeable polyvinyl lined boxes layered on wax‐covered lined paper and blast frozen (–33 °C) for 45 or 90 d after slicing. Retail bacon was vacuum‐packaged in retail packages and refrigerated (2 °C) in the dark for 60 or 120 d after slicing. At the end of respective storage times after slicing, bacon was analyzed for sensory attributes and lipid oxidation. Off‐flavor and oxidized odor of bacon increased (P < 0.01) with increasing storage time in both packaging types. Lipid oxidation increased (P < 0.01) as storage time increased from day 0 to day 45 in food service packaged bacon from frozen bellies, but was unchanged (P ≥ 0.07) with time in food service packaged bacon from fresh bellies. Lipid oxidation was also unchanged (P ≥ 0.21) over time in retail packaged bacon, with the exception of bellies frozen for 5 mo, which was increased from day 0 to day 90. Overall, off‐flavor, oxidized odor, and lipid oxidation increased as storage time after processing increased. Freezing bellies before processing may exacerbate lipid oxidation as storage time after processing was extended.     

Physical and sensory attributes of hot-processed and conventionally chilled hams and bellies from electrically stimulated and non-stimulated pork carcasses

Forty-eight fresh hams and bellies were obtained from 24 market weight hogs (x = 94·5 kg) of which twelve were electrically stimulated (ES) by pulsing current immediately after exsanguination. The left side of each non-stimulated (NS) carcas was fabricated after conditioning for 3h post mortem at 17°C (NS hot-processed). The left sides of ES carcasses were fabricated 1 h pm. The right sides were fabricated following a 24 h cooler chill at 2°C (conventionally chilled: CP). Hams from ESCP carcasses had higher (P < 0·05) smokehouse yields than hams from NS carcasses. Hams that were hot-processed had higher smokehouse yields than the NSCP hams. Time of fabrication (1, 3 or 24h post mortem) did not affect smokehouse yields. Conventionally chilled bellies obtained from ES carcasses showed higher (P < 0·05) residual nitrite levels than those front electrically stimulated hot-processed (ESHP) carcasses. No differences were found for residual nitrite levels in the non-electrically stimulated sides. Panelists were unable to detect any sensory differences from the bacon strips. Sensory scores of ham slices were more juicy for non-stimulated hot-processed carcasses (NSHP) than those from ESHP carcasses. Panelists found the ham slices from NSCP carcasses to be more tender (P < 0·05) than those from electrically stimulated cold-processed (ESCP) carcasses. Results from this study clearly indicated that hot-processing of pork can provide hams and bellies that are acceptable for the production of cured hams and bacon of comparable quality and yield to those currently being produced under conventional processing methods.     

Effect of Rapid Chilling and Accelerated Processing on the Physical and Sensory Characteristics of Cured Pork Bellies

The effects of accelerated and conventional processing systems on the physical and sensory characteristics of cured pork bellies were investigated using three accelerated processing systems. Accelerated processing, with or without electrical stimulation, was effective in producing bellies and bacon strips equal to or superior to those which were conventionally processed. Non stimulated accelerated processing samples were evaluated as being less crispy than other treatments. Rapid chilling in conjunction with accelerated processing, with or without the aid of electrical stimulation, can produce cured bellies as well as bacon slices that are comparable in all traits with bellies from conventionally processed carcasses.     

PROCESSING AND PALATABILITY CHARACTERISTICS OF ROUND BEEF BACON

The objective of this study was to evaluate the effects of tumbling, maceration, and emulsion coating on the processing and palatability characteristics of round beef bacon. Fifty-one beef plates were cured and assigned to treatments: vacuum-tumbled (T); macerated and vacuum-tumbled (MT); macerated, emulsion-coated, and vacuum-tumbled (MET); and emulsion-coated and vacuum-tumbled (ET). Plates were rolled longitudinally, stuffed in fibrous casings, and smoked. Visual bind, visual appearance, and binding strength were lower (P < 0.05) for MET bacons than all other treatments. T bacons were more (P < 0.05) uniform in cured color than MET bacons. There were no differences (P > 0.05) among treatments for visual fat to lean ratio or sensory properties. ET bacons had higher processing yields (P < 0.05) than T or MT bacons, and T bacons higher processing yields (P < 0.05) than MT bacons. Results of this investigation indicate that only vacuum-tumbling is needed to produce an acceptable round beef bacon product.     

Chemical, Physical and Sensory Attributes of Pre- and Post-Chill Processed Hams and Bellies

Hams and bellies from 4 control carcasses and 12 conditioned carcasses were evaluated to determine the physical, chemical and sensory characteristics of pre- and post-chill processed hams and bellies. Processing yields, chemical analyses and sensory characteristics of the hams were not significantly affected by processing treatment. Final yields for the control, post-chill bellies were higher (P < 0.05) than those for pre-chill bellies. Except for differences in crispness, no differences in sensory attributes were noted for cooked bacon strips. Overall, hams and bellies from conditioned carcasses were comparable to cold processed hams and bellies in each variable evaluated in the study.     

Evaluating the ability to measure pork fat quality for the production of commercial bacon

This study was conducted to evaluate three fat quality measures to characterize the suitability of pork bellies for commercial bacon production. Bellies from six sources (A to F) and two weight ranges (4.5/5.5 kg and 5.5/6.4 kg) were sampled by randomly selecting 50 belly sets from commercial combos of pork bellies from each source. The fat on these 50 individual bellies was assessed for quality using three methods: an FTNIR spectrophotometer to predict iodine (IV) value, a Durometer to assess fat firmness, and a subjective fat quality score (FQS) to assess integrated values of fat color, firmness, oiliness, and wetness. Data show that the fat quality measures differed (P < 0.05) by pork belly source and weight class with significant interactions between the two. Bellies were subsequently manufactured into bacon and bacon slicing yield index varied significantly (P < 0.05) by belly source, weight class, and their interaction. Durometer and FQS results were significantly (P < 0.05) correlated with bacon slice yield. The 50 belly subsamples obtained from each source/weight class also allowed the prediction of frequency distribution-based values based on fat quality measures (proportion IV > 74, proportion Durometer value < 50, and proportion FQS > 3. These were also correlated with slice yield. The data lead to a new paradigm model that is useful to describe both the uncertainty in fat quality measures and the relationships observed from pork bellies from different sources.     

Influence of Tumbling on Pickle Incorporation, Yield, and Quality of Bacon

The influence of tumbling on pickle incorporation, yield and quality of bacon was evaluated. Pork bellies (300) were assigned to five processing treatment groups: multineedle injection, multineedle injection then vacuum tumble, vacuum tumble plus free pickle, vacuum tumble (with injection needles exposed) plus free pickle, and vacuum tumble while pickle injecting. Although treatment differences existed for pickle incorporation and yield, no treatment was consistantly superior for pickle incorporation, yield, and quality. Nitrosopyrrolidine levels in samples from all treatments were acceptable according to USDA standards. A positive correlation existed between carcass backfat thickness and pickle incorporation in bellies multineedle injected, but negatively correlated when tumbled. Carcass backfat thickness and hot carcass weight were positively correlated to final bacon yield regardless of treatment.     

Processing and Sensory Properties of Round Pork Bacon

Pork bellies were cured and assigned to five treatments (n = 10). Round bacon was prepared from tumbled (T), macerated and tumbled (MT), emulsion-coated and tumbled (ET), or macerated, emulsion-coated and tumbled (MET) bellies and compared to control slab bacon. Treated bellies were rolled longitudinally and stuffed into fibrous casings. Bacons were smoked and cooked to 55°C. Few differences were observed between treatments for visual characteristics (binding, cured color, fat/lean ratio). Control slab bacon had greater (P <0.05) off-flavor intensity than all other treatments and MT had the highest (P <0.05) overall acceptability scores. Control slab bacon had lower slicing yield (P <0.05) than all other treatments.     

Effect of Belly Handling (Chilled, Frozen, Prerigor) and Smoking Delay on Regular and Sorbate-Cured Bacon

Bellies from three handling methods; fresh, frozen, or prerigor were cured with either 40 ppm sodium nitrite/0.26% potassium sorbate or 120 ppm sodium nitrite. After pumping, one group of bellies was processed (cooked and smoked) immediately, and the remaining group was held 72 hr before processing. Residual nitrite was significnatly higher in regular cure bacon and in bellies processed immediately. By 28 days after packaging, little difference was seen in residual nitrite as a result of any treatment. Regular bacon and immediate processing resulted in greater nitrosopigment conversion. Prerigor bacon had greater pigment conversion and greater residual NaCl concentrations while fresh and frozen bellies were similar. Nitrosamine levels were not influenced by belly handling variables.     

CONSUMER EVALUATION OF THE PALATABILITY OF USDA SELECT,USDA CHOICE AND CERTIFIED ANGUS BEEF STRIP LOIN STEAKS FROM RETAIL MARKETS IN LUBBOCK,TEXAS, U.S.A.

ABSTRACT

Select, Choice and Certified Angus Beef (CAB) strip loin steaks were sold in Lubbock, TX to determine consumer acceptability. A home survey was attached to each package of steaks (return = 191 steak evaluations). Consumers did not detect differences in tenderness or flavor, but rated CAB steaks juicier (P < 0.05) than Select or Choice. However, 68% of CAB consumers rated steaks as extremely or very tender, but less than half rated Choice and Select steaks the same way. Consumer tenderness and flavor scores for Select steaks were more variable, but consumer satisfaction and tenderness acceptability did not differ (P > 0.05) between grades. Trained sensory panelists rated CAB steaks higher (P < 0.05) than Choice or Select for all palatability traits except flavor intensity. Shear force decreased (P < 0.05) by quality grade as CAB steaks sheared with the least resistance. These results showed marbling influenced objective palatability measures and decreased the variation in both objective and consumer measures of palatability.

PRACTICAL APPLICATIONS

Quality grades were established to predict beef palatability, but marbling can be an unreliable predictor of tenderness. Branded beef programs, such as Certified Angus Beef (CAB), have been developed to distinguish higher palatability products and provide more consistent products for consumers. Consumers can distinguish between levels beef tenderness and are willing to pay a premium for tender beef. Moreover, consumers find product consistency is moderately important when purchasing fresh beef. Therefore, the purpose of this study was to determine consumer acceptability based on in‐home evaluations of strip loin steaks from United States Department of Agriculture Select and Choice grades and CAB purchased from a retail supermarket environment.

     

Dry versus wet aging of beef: Retail cutting yields and consumer palatability evaluations of steaks from US Choice and US Select short loins

Paired beef short loins from US Choice (n=48) and US Select (n=48) carcasses were assigned to be dry or wet aged for 14, 21, 28 or 35d. After aging, short loins were processed to determine retail yields and processing times. Upon completion of cutting tests, steaks were served to consumers to assess palatability characteristics. Retail cutting tests showed that dry-aged short loins had reduced yields and increased cutting times when compared to wet-aged short loins. Consumers were unable to determine differences between dry- and wet-aged steaks and for aging periods; however, USDA quality grade had a significant impact on consumer perception of palatability attributes.     

Consumer choice of pork chops in Taiwan

Digital photographs of pork chops varying systematically in appearance were presented to 716 Taiwanese consumers in a study that aimed to identify the most important characteristics of fresh pork which determine consumer choice in Taiwan. Relationships between consumer segmentation in choice and socio-demographic and cultural differences were also investigated. Colour and fat cover were the most frequently chosen of the four characteristics studied. Dark red colour was preferred by 64% of consumers and lean fat cover by 44%. Marbling and drip were less important in the decision making process being used by less than a half of consumers. The four preference-based clusters of consumers showed no correlation with socio-demographic-based consumer clusters, but did show significant links with possession of a refrigerator, age at which schooling was completed, liking pork for its price and gender of consumer.     

Survival and growth of Clostridium perfringens in commercial no-nitrate-or-nitrite-added (natural and organic) frankfurters, hams, and bacon

The popularity of "preservative-free" foods among consumers has stimulated rapid growth of processed meats manufactured without sodium nitrite. The objective of this study was to quantify the potential for Clostridium perfringens growth in commercially available processed meats manufactured without the direct addition of nitrite or nitrate. Commercial brands of naturally cured, no-nitrate-or-nitrite-added frankfurters (10 samples), hams (7 samples), and bacon (9 samples) were obtained from retail stores and challenged with a three-strain inoculation (5 log CFU/g) of C. perfringens. Reduced inhibition (P < 0.05) was observed in seven brands of frankfurters, six brands of hams, and four brands of bacon when compared with each respective sodium nitrite-added control. In naturally cured and truly uncured commercial frankfurters, growth over time was approximately 4.7 log, while conventionally cured frankfurters exhibited growth at 1.7 log. Naturally cured ham and bacon products exhibited growth at 4.8 and 3.4 log, respectively, while their conventionally cured counterparts exhibited growth at 2.6 and 2.3 log, respectively. These products also demonstrated variation in growth response. The results indicate that commercially available natural/organic naturally cured meats have more potential for growth of this pathogen than do conventionally cured products. Natural and organic processed meats may require additional protective measures in order to consistently provide the level of safety from bacterial pathogens achieved by conventionally cured meat products, and which is expected by consumers.     

Acceptability of Bacon as influenced by the Feeding of Elevated Levels of Monounsaturated Fats to Growing-finishing Swine

The acceptibility of bacon produced from swine fed diets containing elevated levels of oleic acid was evaluated. Slicing yields and sensory scores for overall palatability and flavor quality were lower for bacon produced from swine fed canola oil (P < 0.05). A higher percentage of panelists detected off-flavors in canola oil bacon than in bacon produced from swine fed safflower oil, sunflower oil, animal fat or a typical corn-soybean meal diet (P < 0.05).     

Effects of feed treatment and gender on the flavour and texture profiles of cured and uncured pork cuts. I. Ractopamine treatment and dietary protein level

Equal numbers of barrows (64) and gilts (64) were randomly allocated to two separate diets containing 17·6 and 19·6% crude protein. Subsequently within each gender/diet treatment group, pigs were equally and randomly assigned to two ractopamine treatment groups (i.e. 0 or 20 ppm ractopamine), resulting in 16 pigs per gender/diet/ractopamine subgroup. The feeding trial lasted an average of 41 days, and the pigs went on trial at an average weight of 64·5 kg and were slaughtered at an average weight of 98·2 kg. Five barrows and five gilts were subsampled at random from each gender/diet/ractopamine subgroup for palatability evaluations. Comprehensive palatability evaluations were conducted on both cured and uncured pork cuts. Results revealed no meaningful differences in flavour, texture, or cooking properties attributable to dietary protein level (17·6 vs 19·6% crude protein) or to ractopamine. Thus, within the context of conditions employed in the present study, ractopamine can be administered with different dietary crude protein levels to improve production efficiency and carcass composition, without influencing palatability and cooking properties or consumer acceptance. Gender effects have been reported elsewhere (Jeremiah et al., 1994).     

EFFECT OF ENZYMATIC TENDERIZATION, BLADE TENDERIZATION, OR PRECOOKING ON SENSORY AND PROCESSING CHARACTERISTICS OF BEEF BACON

The objectives of this study were to evaluate the effects of enzymatic tenderization, blade tenderization, or precooking on the visual and palatability attributes of beef bacon. Injection of 30 ppm bromelin into beef plates processed into beef bacons significantly (P < 0.05) reduced visual binding and appearance scores compared with the control, 10 ppm- and 20 ppm-injected products. Bacons produced from Choice grade carcasses were saltier, more bacon flavored, softer, higher in fat content, and had lower shear force values than bacons produced from Utility grade carcasses. Precooking of injection-cured beef bacons decreased slice integrity, saltiness, and flavor intensity and increased toughness, shear force, and off-flavor compared with the controls.     

Effects of feed treatment and gender on the flavour and texture profiles of cured and uncured pork cuts. II. Ractopamine treatment and dietary protein source

A total of 128 barrows and 128 gilts were equally and randomly allocated to two separate barley-based diets containing two distinct protein sources (soybean meal and canola meal). Subsequently, the pigs within each gender/ diet treatment subgroup were equally and randomly assigned to two ractopamine treatment groups (0 or 20 ppm). The feeding trial lasted an average of 42 days. The pigs went on trial at an average weight of 67·9 kg and were slaughtered at an average weight of 101·9 kg. Ten pigs selected at random from each gender/diet/ractopamine subgroup were utilized for detailed palatability evaluation. These comprehensive palatability evaluations were conducted on both cured and uncured pork cuts. Results revealed no differences of practical importance in flavour, texture, or cooking properties attributable to dietary protein source or to administration of ractopamine, despite the fact a few statistically significant differences were observed. Thus, ractopamine can be administered with different dietary protein sources to improve production efficiency and improve carcass composition, without influencing palatability and cooking properties, or consumer acceptance. Gender effects have been reported elsewhere (Jeremiah et al., 1994b).