Loin Sections Research Articles

THE EFFECT OF VITAMIN‐MINERAL NUTRITIONAL MODULATION ON THE PORK QUALITY OF HALOTHANE CARRIERS1

ABSTRACTEffects of vitamin/mineral nutritional modulation, preslaughter stress, and hot‐fat trimming (HFT) on traits of 60 market hogs carrying one mutated copy of the halothane gene were determined. Both supplemented treatments resulted in more backfat over the longissimus muscle (P < 0.05) and darker Hunter L* values for the semimembranosus muscle (P < 0.05). Purge from the vacuum‐packaged loin sections during 7 days of storage at 2C was reduced. Supplemented treatments had lower Hunter L* readings for the semimembranosus muscle (P < 0.05). Treatments did not affect muscle palatability. Shelf‐life, water holding capacity and color of muscle was improved in chops from supplemented pigs (P < 0.05). HFT and transporting pigs for an additional 2 h did not affect meat quality. This study demonstrated advantages for improving pork muscle quality from pigs fed the vitamin/mineral supplement for at least 4 weeks before slaughter of market pigs monomutant for the halothane gene.

Injection of beef strip loins with solutions containing sodium tripolyphosphate, sodium lactate, and sodium chloride to enhance palatability.

Beef strip loins (46 U.S. Choice loins and 49 U.S. Select loins) were used to evaluate the potential for enhancing beef tenderness, juiciness, and flavor by injecting fresh cuts with solutions containing sodium tripolyphosphate, sodium lactate, and sodium chloride. One half of each loin served as an untreated control, and the other half was injected with either distilled water (110% of raw weight) or a solution containing phosphate/lactate/chloride solution (107.5, 110, 112.5, or 115% of raw weight). All phosphate/lactate/chloride solutions were formulated to produce injected product concentrations of .25% sodium tripolyphosphate, .5% sodium chloride, and 2.5% sodium lactate. Ten additional U.S. Select loins were injected to 110% of raw weight with a phosphate-only solution (final product concentration of .25% sodium tripolyphosphate) for comparison with Select loins injected to 110% with phosphate/lactate/chloride and with distilled water. Steaks from each control and treated loin section were cooked to two final internal temperatures (66 degrees C and 77 degrees C) for sensory panel evaluation and shear force measurement. Injection of subprimal cuts with phosphate/lactate/chloride solutions improved tenderness (P < .05), juiciness (P < .05), and cooked beef flavor (P < .10) of strip loin steaks and was especially effective for maintaining tenderness and juiciness of steaks cooked to the higher final internal temperature. Injection of Select loins with a solution containing only sodium tripolyphosphate was not effective for improving beef tenderness or juiciness and tended to impart off-flavors characterized by sensory panelists as soapy and sour. Injection of fresh cuts with phosphate/lactate/chloride solutions could assist the beef industry's efforts to improve product quality and consistency.

The influence of controlled atmosphere storage on the flavor and texture profiles of display-ready pork cuts

A total of 216 commercial pork loin sections were utilized to investigate the influences of storage atmosphere, temperature, and time on the flavor and textural properties of display-ready cuts. Storage atmosphere and temperature exerted little influence on flavor and textural properties when data were pooled over storage time and storage atmosphere or storage temperature. However, both flavor and texture deteriorated progressively ( P ≤ 0.05) as storage was extended, and storage time accounted for 94 and 91%, respectively, of the variation in texture and flavor amplitude ratings when data were pooled over storage atmosphere and storage temperature. Normal flavor character notes became less prevalent and less intense ( P ≤ 0.05), and were detected later ( P ≤ 0.05), while unusual flavor character notes became more prevalent and intense ( P ≤ 0.05), and were detected earlier ( P ≤ 0.05) as storage was extended, resulting in the flavor of samples becoming unusual, unbalanced, and unblended after 12 days of storage, when data were pooled over storage atmospheres and storage temperatures. Consequently, off-flavor development constituted the limiting factor for extension of chilled pork storage life in display-ready packs, masterpacked in controlled atmospheres. Since previous research has illustrated early off-flavor development coincided with lactics reaching maximum numbers, extension of the chilled storage life of display-ready pork is dependent upon substantially improving the hygienic quality of commercial pork products.

Suppression of off-odour in irradiated chicken using dietary added antioxidants

Boneless loins from both sides of 20 pig carcasses were divided into five sections each and assigned equally to five packaging treatments: 100 % CO2; 50 % CO2/50 % N2; 25 % CO2/ 75 % N2; 25 % CO2/65 % N2/10 % O2 and vacuum.Loin sections were packaged in bags of low O2 permeability, then stored in darkness at 1 °C for up to 22 days. Retail chops were cut from the sections and displayed in oxygen-permeable film under light at 3 °C for 3 additional days. The O2 concentrations in packages with nominally anoxic atmospheres were 0.1–0.4 %. Sections stored in 25 % CO2/65 % N2/10 % O2 had more surface greying and greening, stronger off-odour and psychrotropic counts after storage were more than one log10 higher compared to sections from the other four treatments. Displayed chops from sections stored in 25 % CO2/65 % N2/10 % O2 also had greying/greening at an outer layer of the chops. Off-odour of chops was most pronounced for treatments with 10 % O2 and vacuum. Drip loss from loin sections was highest for those in 100 % CO2 (4.2 %) and lowest for those in vacuum (3.2 %). In conclusion, storage in CO2 or CO2N2 atmospheres benefitted the overall shelf life of pork.

Effects of modified gas atmosphere packaging on pork loin colour, display life and drip loss

Boneless loins from both sides of 20 pig carcasses were divided into five sections each and assigned equally to five packaging treatments: 100 % CO 2; 50 % CO 2/50 % N 2; 25 % CO 2/ 75 % N 2; 25 % CO 2/65 % N 2/10 % O 2 and vacuum. Loin sections were packaged in bags of low O 2 permeability, then stored in darkness at 1 °C for up to 22 days. Retail chops were cut from the sections and displayed in oxygen-permeable film under light at 3 °C for 3 additional days. The O 2 concentrations in packages with nominally anoxic atmospheres were 0.1–0.4 %. Sections stored in 25 % CO 2/65 % N 2/10 % O 2 had more surface greying and greening, stronger off-odour and psychrotropic counts after storage were more than one log 10 higher compared to sections from the other four treatments. Displayed chops from sections stored in 25 % CO 2/65 % N 2/10 % O 2 also had greying/greening at an outer layer of the chops. Off-odour of chops was most pronounced for treatments with 10 % O 2 and vacuum. Drip loss from loin sections was highest for those in 100 % CO 2 (4.2 %) and lowest for those in vacuum (3.2 %). In conclusion, storage in CO 2 or CO 2 N 2 atmospheres benefitted the overall shelf life of pork.

The influence of inherent muscle quality upon the storage life of chilled pork stored in CO 2 at −1.5 °C

A total of 120 pork loin sections (1 kg) representative of five inherent muscle quality groups [24 each; extremely PSE (pale, soft and exudative), PSE, normal, DFD (dark, firm and dry), and extremely DFD]were used to evaluate the effects of inherent muscle quality on the keeping quality of chilled pork stored for up to 15 weeks in CO 2 at −1.5 °C. B. thermosphacta, pseudomonads, and enterics did not grow on any muscle quality group during storage in 2.5 1 of carbon dioxide per kg of product. Lactic acid bacteria became the dominant flora on all muscle quality groups during storage and reached maximum numbers during the first six weeks of storage. Purge losses increased during the first three weeks of storage from all muscle quality groups but were generally the highest from pork with normal muscle quality throughout storage. The pH of pork with PSE characteristics tended to normalize with extended storage, and the color of pork with extremely aberrant quality appeared to normalize by approximately one level of muscle quality after 15 weeks of storage. Pork with DFD characteristics required the longest duration of storage to display surface discoloration. The retail appearance of pork from all muscle quality groups was well within the acceptable range after 15 weeks of storage, but the retail appearance of pork with normal and DFD characteristics deteriorated progressively during storage. Off-odors became detectable in all muscle quality groups after 12 weeks of storage but were more pronounced from pork with DFD characteristics. However, the intensity of these off-odors did not become more than slight even in DFD samples. Although the odor acceptability began to decline after 12 weeks of storage, all samples remained quite acceptable in odor after 15 weeks of storage. Muscle quality exerted little influence on cooking times and losses throughout storage. Pork with normal quality characteristics was generally less tender prior to storage. Although muscle quality exerted little influence on other palatability attributes, both flavor desirability and overall palatability deteriorated during storage in all samples and reached the point of unacceptability after six weeks of storage, when lactic acid bacteria attained maximum numbers.

The influence of controlled atmosphere and vacuum packaging upon chilled pork keeping quality

A total of 48 pork loin section (1 kg) with normal inherent muscle quality were utilized to evaluate and compare the effects of a vacuum packaging system and a CO 2 controlled atmosphere packaging system on keeping quality of chilled pork stored at −1·5°C. Results indicated based upon appearance CO 2 packaged porl loin had a storage life of greated than 15 weeks and vacuum packaged pork loid had a storage life of slightly over 12 weeks. However, off-flavor development coinciding with lactic acid bacteria reaching maximum numbers presently restricts the actual storage life of pork loin stored at −1·5°C to 9 weeks in both packaging treatments. Therefore, if microbial contamination on the commercial product can be reduced significantly to prevent spoilage organisms, including lactics, from rapidly growing to maximum numbers, storage life of pork loin at −1·5°C can be extended sufficiently to accomodate all domestic and export applications using either vacuum or CO 2 packaging.

PALATABILITY AND VISUAL CHARACTERISTICS OF HAMS AND LOIN CHOPS FROM SWINE TREATED WITH RACTOPAMINE HYDROCHLORIDE

ABSTRACTThis study was designed to evaluate the visual and palatability characteristics of boneless cured hams and fresh loin chops from pigs fed diets containing 0, 5, 10 or 20 ppm of the phenethanolamine, ractopamine hydrochloride (RAC). Sixty pigs were blocked by starting weight and randomly assigned to pens (four pigs/pen) within each of three blocks. Treatments were then randomly assigned to pens (six pens of the 0–ppm level and three pens each for the 5, 10 and 20 ppm RAC levels). Animals were slaughtered by weight block after approximately 48 days on trial. Fresh pork hams and loin sections (10–14th rib) were removed from the right side of the carcasses for subsequent analysis. Boneless hams were manufactured using commercial curing procedures. RAC had no effect (P &gt; 0.05) on visual or palatability attributes of ham slices or boneless loin chops. Moisture content of the longissimus muscle from RAC treatments was lower (P &lt; 0.05) than controls; however, this difference was small. These results indicate that RAC had no affect on the visual or palatability characteristics of boneless cured and smoked hams or fresh boneless pork loin chops.

The prediction of percentage of protein in pork carcasses

Determination of percentage of protein in a pork carcass is a very costly and lengthy process. Therefore, we attempted to identify an easy and economical means to predict protein content of pork carcasses. Forty-seven market-weight pigs were slaughtered. The right side of each carcass was skinned, deboned and ground for composition analysis. Carcass data were collected on the left side and specific gravity analysis was performed on the side, ham and 8-9-10 rib loin section of each carcass. The hams and loin sections were dissected into skin, bone, subcutaneous fat, seam fat and individual muscles. After these components were weighted, they were analyzed for chemical composition. Percentage of chemical protein of each animal was determined and correlated with each of the weights and measurements taken on the carcass, ham and loin sections. Stepwise regression was used to predict decimal fraction of protein using either the carcass data, specific gravity ham measurements, loin section measurements or various combinations of these. In prediction equation, specific gravity of the carcass accounted for 73.4% of the variation found in percentage of protein. Prediction equations using indicators from the ham and loin section resulted in equations with R-square values as high as .783. These results suggest that specific gravity or indicators from the carcass, ham or loin section can be employed to predict percentage of protein in pork carcasses.

The prediction of percentage of fat in pork carcasses

Forty-seven market-weight pigs were slaughtered in order to determine percentage of chemical fat and in an attempt to determine an easily obtainable and inexpensive method to predict this value. The hams and 8-9-10 rib loin sections were removed from the left side of each carcass and dissected into subcutaneous and seam fat, individual muscles, skin and bone. Weights and chemical analysis were determined for each component. Numerous weights, measurements and specific gravity were determined on the carcass, ham and loin section of each pig. Percentage of chemical fat of each ham, loin section and carcasses was determined and correlated with the various weights and measurements taken. Stepwise regression was used to develop prediction equations using carcass data, specific gravity, ham or loin measurements or various combinations of these as dependent variables. The single best indicator of the decimal fraction of chemical fat in the pork carcass was determined to be specific gravity of the carcass half, the prediction equation using this variable had an R-square of .64. By adding 10th rib fat thickness to this equation, the R-square increased to .72. The best equation using carcass variables included 10th rib fat and marbling (R-square = .67). The loin section proved to be an accurate indicator of composition; ham measures were not as accurate as specific gravity and carcass measurements for predicting percentage of carcass fat. This research suggests that the percentage of chemical fat in the pork carcass can be predicted by an easy and inexpensive means.

A note on the nutritive value and acceptability of peat in the diet of lambs

Lambs were fed diets in which peat replaced equivalent alfalfa hay. Gains were depressed by proportionately 0·14, 0·32 and 0·56 due to 100, 200 and 300 g peat per kg, respectively, during a 63-day feeding period. Lambs fed peat required more dry matter per unit gain. Necropsy examination of heart, kidney, liver, spleen, lung, and pancreas revealed no gross abnormalities from feeding of peat. Rib eye area was reduced at 200 and 300 g dietary peat per kg. There were no differences in taste of cooked loin sections due to peat. These studies support the safety of feeding peat for use as a dietary carrier at 20 to 30 glkg diet or as a dietary diluent at higher levels.

Ineffectiveness of Three Added Mold Species to Enhance the Rapid Aging of Beef

Paired beef short loin sections from four U.S. Good and four U.S. Choice carcasses were used to determine the effects of the mold Thamnidium elegans on cooking and palatability characteristics. The longissimus muscle from each section was treated with mold spores and aged for 2 or 4 d or left untreated and aged for 2 or 14 d at 4°C. Sensory panel ratings revealed that mold treatment had no significant effect (P<0.05) on tenderness, juiciness, detectable connective tissue amount, or beef flavor intensity of the loins aged for 2 d. Thawing loss, cooking loss, cooking time, Instron shear force and work force values were not affected (P>0.05) by treatment with T. elegans. Aging untreated meat for 14 d significantly improved (P<0.05) sensory panel ratings for tenderness. No significant difference (P>0.05) was noted between mold treatments (2 and 4 d) when compared to the 14-d untreated aging, for beef flavor intensity, detectable connective tissue amount, shear and work force values. Significant grade effects were noted with U.S. Choice samples having higher (P<0.05) sensory panel ratings for juiciness and beef flavor intensity, and decreased (P<0.05) ratings for connective tissue amount when compared with U.S. Good samples. The data indicate that treatment of sub-primal cuts with T. elegans has little or no effect on palatability and cooking characteristics.

Carcass and meat quality characteristics and backfat fatty acid composition of swine as affected by the consumption of peanuts remaining in the field after harvest.

Carcass composition, meat quality characteristics and changes in backfat fatty acid composition of swine that were allowed to obtain part or all of their weight gain during the growing-finishing period from gleaning peanuts remaining in the field after harvest were evaluated. Thirty-six cross-bred pigs (18 barrows, 18 gilts) were allotted evenly among the following six treatments: 1) fed a corn-soybean meal-based diet (C) from 26 to 104 kg (CCC); 2) gleaned peanuts (P) from 26 to 102 kg (PPP); 3) C from 26 to 78 kg and P from 78 to 103 kg (CCP); 4) P from 26 to 55 kg and C from 55 to 105 kg (PCC); 5) C from 26 to 56 kg and P from 56 to 103 kg (CCP); 6) P from 26 to 79 kg and C from 79 to 106 kg (PPC). Carcasses from all treatment groups were similar in composition. Carcass fat of pigs in CPP, PPC and, in particular, PPP groups was softer than that from pigs in CCC, CCP and PCC groups. Ratio of unsaturated to saturated fatty acids in backfat increased in proportion to the amount of weight gained while pigs gleaned peanuts. Loins from pigs in the PPP and CPP treatment groups received lower marbling scores than those from the CCC group, but the fat content of the loin was not affected by treatment. No differences were detected between treatment groups in shear force values or sensory panel attributes of broiled loin chops, or in thiobarbituric acid values of vacuum packaged loin sections frozen for 4 mo.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of Different Chilling Methods on Hot Processed Vacuum Packaged Pork

ABSTRACTLongissimus muscle (loin section) was removed from each side of 24 pork carcasses within 20 min postmortem. Each muscle was divided in half (N = 96 sections), vacuum packaged and allotted to one of four treatments: (1) normal chilling, (2) propylene glycol immersion, (3) crust freezing, or (4) high temperature conditioning and four storage intervals (N = 6) or 0, 7, 14 or 28 days. Rapid chilling with propylene glycol increased (P&lt;0.05) purge. Shear force values were increased when loins were rapidly chilled (P&lt;0.05) but few sensory differences were observed. Off‐odor scores increased (P&lt;0.05) with increasing storage time. Normal chilling resulted in lighter muscle color scores than rapidly chilled loin sections. Rapid chilling does not have a beneficial effect on palatability or shelf life of hot‐processed fresh pork.

Effects of Packaging and Processing Procedures on the Quality and Shelf Life of Fresh Pork Loins

ABSTRACTThirty crossbred hogs were slaughtered and the longissimus muscle from the left side was removed and divided into two equal sections within 20 min postmortem (HP) and those from the right side were removed and divided 24 hr postmortem(CP). One‐half of the muscle from each side was wrapped in parchment paper (PP) and the other half was vacuum packaged (VP) and loin sections were assigned to storage intervals of 0, 7, 14, 21, or 28 days. At the end of each storage period, loins were evaluated for moisture loss, bacterial levels, off‐odor, sensory properties and retail case display. VP and HP treatments had reduced moisture loss (P&lt;0.05). Off‐odor scores were higher (P&lt;0.05) for PP wrapped loins on day 14. Few palatability differences were observed with packaging and processing treatments. Vacuum packaging had positive effects on the storage and retail display characteristics of fresh pork.

Effect of Subprimal Fabrication and Packaging Methods on Palatability and Retail Caselife of Loin Steaks from Lean Beef

ABSTRACTEighty subprimals were fabricated from 20 pairs of beef strip loins from lean (fat thickness, 0.2‐0.4 cm) US Standard and US Good carcasses. Three vacuum packaged (VP) and one dry aged treatments were randomly assigned to short loin sections of each carcass. Steaks from VP intact and VP not‐reassembled subprimals were rated highest in overall appearance and eating quality. Dry aging reduced retail caselife, produced greater shrinkage and trim losses and lower overall satisfaction ratings by panelists. Precutting subprimals into steaks followed by VP aging tends to decrease retail caselife (especially if steaks are reassembled) and decrease juiciness and tenderness.

SLAUGHTER AND CARCASS CHARACTERISTICS OF CATTALO, HEREFORD, AND 1/4 BRAHMAN–3/4 HEREFORD YEARLINGS

Slaughter and carcass data were obtained from 60 cattalo that averaged 1/7 bison–6/7 domestic (27 bulls, 33 heifers), 19 Hereford (11 bulls, 8 heifers), and 17 1/4 Brahman–3/4 Hereford (12 bulls, 5 heifers) yearlings. At a constant age, 1/4 Brahman and Hereford exceeded cattalo in growth rate, i.e. slaughter weights were: 1/4 Brahman 381 ± 10 kg, Hereford 376 ± 8 kg, and cattalo 353 ±5 kg. At a constant 24-h cold carcass weight, cattalo exceeded Hereford in carcass length (2.3%). Breed groups did not differ in mean fat thickness over, or area of, the longissimus dorsi, dressing percent, or transit shrink. At a constant carcass weight, the weight of the loin section was similar in all breed groups, but Hereford exceeded cattalo in round weight (2.6%), cattalo surpassed 1/4 Brahman in rib weight (4.3%), and 1/4 Brahman exceeded Hereford in shoulder weight (3.2%). Bison and cattalo were reported to have heavier front than rear quarters. This study suggests that the cattalo were not heavier in the shoulder but were lighter in the round than the Hereford and that the difference basically was in the weight of the hind shank.

A Reasearch Note VITAMIN B6 IN PORK MUSCLE COOKED IN MICROWAVE AND CONVENTIONAL OVENS

Loin sections of pork muscle were heated to 75 or 85°C internal temperatures in microwave or conventional electric ovens. Cooking losses and time, percentage moisture and total vitamin B6 were determined. Cooking time was longer, total cooking loss less and moisture content greater for pork cooked in an electric oven than for that cooked in a microwave oven. Differences in vitamin B6 due to type of oven or internal temperature were small and not significant when calculated on a cooked weight basis. When calculated on a dry weight basis samples cooked in the conventional oven contained more vitamin B6 than did those cooked by a microwave oven.

TENDERNESS OF BEEF LONGISSIMUS DORSI MUSCLE FROM STEERS, HEIFERS AND BULLS AS INFLUENCED BY SOURCE, POST‐MORTEM AGING AND CARCASS CHARACTERISTICS

SUMMARY Cooked steaks from the commercial rib and short loin sections of 168 steer, 143 heifer and 259 bull carcasses were sampled, ribs at one, two and three and loin at two, three, six and 13 days post‐mortem, to evaluate aging patterns on beef tenderness. Steaks from the rib section were more tender than from the short loin section. Aging patterns were similar for all sexes and stations of origin. Shear values dropped 12% over three days post‐mortem in the rib steaks. Shear value from steaks from the loin section did not reduce over the first three days, but between day 3 and day 6 shear values fell 14% and continued to fall at reduced rate (about 1.6% per day) between day 6 and day 13. There was no evidence of any influence of finish, marbling or muscle color on rate or extent of aging on tenderness. Chemical fat determinations and visual marbling scores were only moderately correlated. Similar correlations were found between marbling score and finish (i.e., rib fat measurements). Correlations between 24 hr pH and color of the muscle were moderate to high with marked sex heterogeneity. Correlations involving color and shear value were significant but not consistent among sexes nor among aging periods. It was concluded that with youthful carcasses of all sizes, sexes and degrees of fatness a cooler aging period of six days was sufficient for producing a consumer product of satisfactory tenderness.

Iron Sulfide Blackening in Canned Protein Foods. Interactions of Constituents in the Vapor Phasea

SUMMARYThe formation of volatile bases and volatile acids during heat processing of albacore tuna loin sections was studied, using a closed system swept with nitrogen gas. The cell containing the tuna was heated gradually to 100°C, and the volatile acids and bases were trapped in standardized solutions. During the first 80 min of heating, at precooking temperatures, volatile acid evolved exceeded by threefold the slight amounts of volatile base (less than 0.5 mcq per 1000 g). Later during the heating cycle equal amounts of volatile acids and bases were formed.The ratio of sulfur to iron responded directly to the initial vacuum present in canned tuna. At high vacuum the ratio was 0.575. Sulfur was absent from the black deposits when the cans were sealed without evacuation, even when high levels of cystine were added. In commercially packed shrimp the sulfur to iron ratio was 0.322, which is consistent with a deposit of mixed oxides of iron, combined with ferrous sulfide. Addition of acetic acid (a volatile acid) at 10 mM per can suppressed the formation of black deposits at all closing vacuums in a model system containing added cysteine, while the addition of ammonium hydroxide (volatile base) or no addition resulted in the formation of black deposits at 26 inches Hg of closing vacuum.