Biomedical subjects

J R Romans

Publications and source records attributed to J R Romans.

13 recordsLinked to original sources

PubMed1999

Characterization of muscles from boars, barrows, and gilts slaughtered at 100 or 110 kilograms: differences in fat, moisture, color, water-holding capacity, and collagen.

For characterization of ether-extractable fat content (EE), L*, a*, and b* color, and water-holding capacity (WHC), 12 muscles or muscle groups were dissected from 48 pork carcasses of boars, barrows, or gilts that were fed diets either at minimum (LO) or 1% above (HI) their protein requirements and slaughtered in two separate trials at 100 or 110 kg. In both trials across muscles, gilts and boars had lower (P < .05) EE than barrows. In the 110-kg trial, boars had lower (P < .001) EE than gilts. In the 100-kg trial, boars on LO diets had lower (P < .001) WHC than all other groups, and both boar groups had lower (P < .05) WHC than gilts. No differences (P > .05) in WHC were seen in the 110-kg trial. In the 100-kg trial, gilts had lower L* (P < .05) than boars and barrows, but in the 110-kg trial boars had lower L* (P < .05) than barrows and gilts. The lowest (P < .05) a* values were for boars in the 100-kg trial and for boars on LO diets in the 110-kg trial. In both trials, the serratus ventralis had more (P < .001) EE than all other muscles. In both trials, the semitendinosus had higher (P < .001) L* and the longissimus had lower (P < .01) a* and b* than all other muscles. The numerous differences observed among muscles may help identify optimal uses for the entire pork carcass.

Adipose Tissue↗

PubMed1997

Sensory characteristics and carcass traits of boars, barrows, and gilts fed high- or adequate-protein diets and slaughtered at 100 or 110 kilograms.

The objective of this study was to determine consumer reaction to boar (BO), barrow (BA), and gilt (G) meat from pigs grown and finished on high- (HI) and low- (LO) protein diets and slaughtered at 100 and 110 kg BW. Within each of two trials, 54 BO, BA, and G were allotted within sexes to HI or LO protein sequences for growing and finishing: 19 and 17% (BOHI), 18 and 16% (BOLO), 17 and 15% (GHI), 16 and 14% (GLO), 15 and 13% (BAHI), and 14 and 12% (BALO). Backfat skatole and salivary gland 16-androstene concentrations were measured from samples taken at slaughter. Longissimus (LM) and semitendinosus (ST) chops from 24 pigs (with equal representation across diet and sex groups) were evaluated by trained panelists for tenderness, juiciness, and off-flavor. Consumer panelists evaluated acceptability of LM chops. In the 100-kg trial, HI diets improved (P < .05) carcass leanness in BO and BA but not in G. In both trials, BO were leaner (P < .05) than G, and both were leaner (P < .05) than BA. Skatole and 16-androstene concentrations were similar (P > .05) among sexes in both trials. In the 100-kg trial, trained panelists found BOLO chops had more (P < .05) off-flavor. In the 110-kg trial, all BO had more off-flavor (P < .05) than BAHI, BALO, and GHI but were similar (P > .05) to GLO. In both trials, BA chops were more tender (P < .05) than G and BO chops and LM chops had less off-flavor (P < .05) than ST chops. In the 110-kg trial, skatole was correlated (r = .28, P < .001) to off-flavor. A relationship may exist among diet, skatole deposition, and off-flavor. Untrained consumers reported all chops were equally acceptable (P > .05).

Androstenes↗

PubMed1997

Fatty acid composition of commercially manufactured omega-3 enriched pork products, haddock, and mackerel.

This study was conducted to determine the commercial feasibility of feeding a 15% ground flaxseed diet to finishing hogs for up to 42 d before slaughter and to compare the fatty acid composition of the resulting pork products with commercially produced haddock and mackerel. Eighty-seven pigs were fed a control diet (predominantly corn, soybean meal-based) and then a similar diet containing 15% flaxseed for the last 28 (FS28) or 42 d (FS42) before slaughter. Control pigs were continued on the control diet (CO28 and CO42). Percentages of saturated and monounsaturated fatty acids were decreased (P < .0001), and percentages of polyunsaturated fatty acids, most prominently alpha-linolenic acid [18:3(n-3)] and the sum of all (sigma) measured (n-3) fatty acids, were increased (P < .0001) in all pork tissues (backfat, liver, and longissimus thoracis) and products (lard, muffins, Braunschweiger, and bacon) due to dietary flaxseed. The percentage of arachidonic acid [20:4(n-6)] decreased in FS28 compared to CO28 liver (P < .0001) and in longissimus thoracis polar fraction FS42 compared to CO42. The percentage of 18:3(n-3) was similar in mackerel, CO bacon, and CO longissimus thoracis, and the percentage of 18:3(n-3) and sigma(n-3) in haddock was similar to that in FS bacon and FS longissimus thoracis. The percentage of 20:5 in FS42 longissimus thoracis, polar fraction, approached the level in haddock, but the percentages of 20:5 and 22:6 were greater (P < .0001) in mackerel than in haddock. The percentage of sigma(n-3) was greater (P < .0001) in mackerel than in haddock and sigma(n-6) was greater (P < .0001) in haddock than in mackerel. Commercial production of omega-3 enriched pork products can provide consumers a feasible alternative to a diet higher in fish than that normally consumed.

Adipose Tissue↗

PubMed1995

Effects of ground flaxseed in swine diets on pig performance and on physical and sensory characteristics and omega-3 fatty acid content of pork: I. Dietary level of flaxseed.

Forty-eight barrows and gilts were fed diets containing 0 (CO), 5, 10, or 15% ground flaxseed (FS) for the final 25 d before slaughter. Flaxseed treatments did not affect any production or carcass traits (P > .10). No pork processing problems due to lack of firmness were encountered. Amounts (milligrams/gram of tissue) of alpha-linolenic acid (ALA [18:3n-3]) and eicosapentaenoic acid (EPA [20:5n-3]) increased (P < .01) in both backfat layers and ALA increased (P < .01) in kidney (leaf) fat after FS. Alpha-linolenic acid and EPA increased (P < .001) in the raw belly in response to FS; the effect was maintained throughout processing (P < .01) to microwaved bacon. Alpha-linolenic acid and EPA increased (P < .01, P < .05, respectively) with amount of FS in longissimus thoracis and liver. In the brain, DHA decreased (P < .05) with amount of FS. Trained panelists in triangle tests were able to identify bacon from pigs fed 10 and 15% flaxseed. Panelists could not identify various treatments in the loin tests.

Animals↗

PubMed1995

Effects of ground flaxseed in swine diets on pig performance and on physical and sensory characteristics and omega-3 fatty acid content of pork: II. Duration of 15% dietary flaxseed.

Four barrows and four gilts were assigned to each of five dietary treatments: a control (CO) diet or a 15% flaxseed (FS) diet fed for 7, 14, 21, or 28 d prior to slaughter. Flaxseed treatments did not affect any production or carcass traits (P > .10). No pork processing problems due to lack of firmness were encountered. Amounts (milligrams/gram of tissue) and percentages of alpha-linolenic acid (ALA [18: 3n-3]), arachidonic acid (AA [20:4n-6]), and eicosapentaenoic acid (EPA [20:5n-3]) increased (P < .001) in both backfat layers and in kidney (leaf) fat and docosahexaenoic acid (DHA [22:6n-3]) increased (P < .006) in the middle/inner backfat layer after FS. The effects of dietary FS on fatty acid profiles were maintained in lard and pastry. Alpha-linolenic acid, AA, and EPA increased (P < .001) and DHA increased (P < .021) in the raw belly in response to FS; the effect was maintained throughout processing to microwaved bacon. Percentage of oleic acid (OA [18:1n-9]) decreased (P < .016) in raw bellies after FS. Alpha-linolenic acid and EPA increased (P < .001) with duration of FS in longissimus thoracis and liver neutral lipids, polar lipids, and combined lipid fractions, but DHA increased (P < .004) only in longissimus thoracis polar and combined lipid fractions. Arachidonic acid decreased in the longissimus thoracis polar lipid fractions (P < .037) and in liver neutral (P < .01) and combined lipid fractions (P < .006) with FS. All ALA:AA and EPA:AA ratios increased (P < .001 to P < .048) with increased duration of FS (except ALA:AA in pastry [P = .56]). Processing of bellies into bacon and storing at -18 degrees C for 6 wk did not cause thiobarbituric acid (TBA) values to exceed a value of 1.0 after either the CO or FS diets. After microwaving bacon when TBA values approached 2.0, there was no FS dietary effect on TBA values. Trained panelists rated FS bacon more flavor-intense than CO bacon and recorded more flavor defects for FS bacon. A 105-member consumer group showed a higher frequency of "dislikes" for FS bacon than for CO bacon.

Adipose Tissue↗

PubMed1994

Current merchandising practices and characteristics of beef wholesale rib usage in three U.S. cities.

Packers/processors, supermarket meat managers, and restaurant meat purchasers were surveyed to determine industry utilization of the beef wholesale rib. Nine packer/processors representing > 52% of the U.S. steer-heifer slaughter reported that more than two-thirds (68.5%) of the ribs were wholesaled as ribeye, lip-on (IMPS 112A) subprimals and that its predominance in the market makes it the standard for pricing. For merchandising variations of this cut (e.g., ribeye, lip-off), packer prices are adjusted to lip-on bases according to the relative yield. Excess fat was the most common complaint about ribeye steaks, reported by 78% of the packer/processors. In particular, 71% of them reported the "kernel" fat near the center of a ribeye steak between the longissimus and spinalis dorsi muscles is quite difficult to trim out and represents the greatest problem in merchandising. Forty-two percent of supermarket meat managers and 58% of restaurant meat purchasers thought the fat content of beef ribeyes discouraged consumers from purchasing all beef. Kernel fat was specifically cited by 36% of the restaurateurs. Alternative merchandising strategies should be employed to minimize the negative value effects of kernel fat. Even with excess fat being a concern to approximately half of the beef rib buyers, most still bought lip-on ribeyes and trimmed excess fat away. Apparently, they made this choice of lower price per weight, even though price per trimmed serving might be similar to lip-off ribeyes. Excess fat is being transported from packer/processor to buyers in the form of lip-on ribeyes because of the price relationships.(ABSTRACT TRUNCATED AT 250 WORDS)

Abattoirs↗

PubMed1994

Composition of the beef wholesale rib.

Wholesale ribs (n = 40) were dissected to determine composition from anterior to posterior end. There were much greater differences in tissue amounts from different anatomical locations within the wholesale rib than between wholesale ribs from carcasses of different USDA yield grades. Kernel fat (seam fat between the longissimus and spinalis dorsi muscles) was found in considerably higher amounts in the 7th, 8th, and 9th rib bone sections. Removal of the lip from IMPS 112A decreased the separable fat content of ribeyes by approximately 46%. This large decrease in fat could make the ribeye more appealing to today's consumer.

Adipose Tissue↗

PubMed1989