摘要:

ABSTRACTThe purpose of this investigation was to determine whether mechanical shear values of the cardiac muscle could be useful in predicting skeletal muscle tenderness as measured by mechanical shear and sensory evaluation methods. The metal ion content of bovine skeletal muscle was also determined and evaluated for its ability to predict skeletal muscle tenderness. W‐B shear results indicate cardiac muscle tenderness is related to semimembranosis tenderness, but the magnitude of the correlation coefficient is not high enough for adequate prediction capabilities. However, the predictive capability of element content is very good for all three tenderness measures‐sensory panel, W‐B and rotary shear. These results indicate the good potential of this approach to tenderness predi

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00713_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACTWholesale beef cuts were vacuum packaged at low, intermediate or high degrees of vacuum and stored at l‐3°C for 7, 14, 21, 28 or 35 days. Purge loss, trim loss, muscle color and odor were not generally affected by degree of vacuum. Fat appearance and surface discoloration ratings for primal cuts favored the use of a high level of vacuum in three of five storage intervals. Total desirability ratings for primal cuts packaged with high vacuum were higher than those for primal cuts packaged with low vacuum at all five storage intervals. Cuts from the low vacuum treatment had consistently higher numerical values for trim loss than did cuts from intermediate or high vacuum level groups, but these differences were not statistically significant. Degree of vacuum used during storage of primal cuts did not generally affect the peripheral discoloration, surface discoloration or total desirability of subsequent retail steaks. However, among primal cuts stored for 21 days, peripheral discoloration and total desirability scores were lowest (P<0.05) for retail cuts from the low vacuum treatment. Differences in juiciness, flavor desirability, overall satisfaction and Warner‐Bratzler shear values for retail steaks were not related to the degree of vacuum used to store primal

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00714_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACTWholesale cuts of fresh beef were vacuum packaged at low, intermediate or high degrees of vacuum and stored at l‐3°C for 7, 14, 21, 28 or 35 days. Bacterial counts of samples after 7 and 14 days of storage were low [mean count<104per in.2(6.45 cm2)] irrespective of degree of vacuum. Lactobacilli and anaerobic agar plate counts of cuts stored under high vacuum for 21‐35 days tended to be lower than those of comparable cuts stored under low or intermediate vacuum. This was also true, but much less frequently, for the psychrotrophic and mesophilic counts. Largest increases in bacterial counts occurred between 14 and 21 days of storage. Fluorescent pseudomonads represented only a small percentage of the total microbial population of vacuum packaged beef cuts. Lactobacilli and anaerobic plate counts of vacuum‐packaged cuts were very similar. The psychrotrophic bacterial population of cuts stored for 28 days consisted primarily ofLactobacillussp., whilePseudomonassp. andEnterobacteriaceaerepresented only a small percentage of the psychrotrophic microflora at tha

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00715_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACTThe effect of processing variables on the texture of cooked, freeze‐dried, beef top round has been studied. Treatments included “tenderstretch” hanging, aging, cooking temperature and time, infusion with salt solutions and use of antioxidants. Texture of meat was improved by “tenderstretch” hanging and rehydration in papain, while there was a large increase in texturometer hardness on high temperature storage. Increasing cooking temperatures resulted in increased hardness up to 75°C, but at 85°C and above decreases occurred. Cooking for 4 hr as compared to 2 hr had no effect at cooking temperatures below 75°C but at 85°C caused a decrease in hardness. Cooking temperature and time did not affect the storage properties of freeze‐dried beef, but coming, infusion with sodium and potassium chlorides and aging all reduced the hardness increase caused by high temp

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00716_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACT40 lambs were selected to vary in amount of finish for use in determining the mechanism by which fatness affects tenderness. Lambs with thick (n = 10), intermediate (n = 20) or thin (n = 10) finish were slaughtered, chilled at 1 ± 1°C and samples obtained from three muscles for chemical, histological, physical and organoleptic analyses. Subcutaneous fat was removed from one side of each carcass in the intermediate finish group to facilitate comparisons on a within‐carcass basis. The data suggest that lamb carcasses which have increased quantities of fat (subjectively determined via live evaluations of finish or objectively determined via subcutaneous fat thickness measurements and marbling scores): (a) chill more slowly; (b) maintain muscle temperatures conducive to autolytic enzyme degradation for greater periods of time postmortem; (c) sustain less shortening of sarcomeres; (d) have muscles with lower ultimate pH values; (e) have less perceptible or softer connective tissue; and (f) are more tender than lamb carcasses which have limited quantities of fat. The data support the hypothesis that deposition of increased quantities of subcutaneous or intramuscular fat (particularly in carcasses with limited quantities of subcutaneous finish) increases tenderness via changes in postmortem chilling rate. An increased quantity of fat decreases the rate of temperature decline (either by insulation or via an increase in carcass mass), enhances the activity (or increases the duration of active proteolysis) of autolytic enzymes in muscle, lessens the extent of myofibrillar shortening and thereby increases the ultimate tenderness of cooked meat from a fatter carc

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00717_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACT“High linoleic” meat with fat containing up to 20% linoleic acid was produced by feeding a protected lipid supplement to sheep and steers. A comparison was made of the frozen storage life of this meat and of conventional meat, packaged in sealed polyethylene film pouches and stored at ‐10°C or at ‐20°C. Peroxide development was much more rapid in adipose tissue from high linoleic meat stored at ‐10°C. Rate of peroxide development in high hnoleic meat was greatly decreased when stored at ‐20°C. Taste panel assessments indicated that high linoleic meat stored at ‐10°C developed rancid odors and flavors 2‐3 times more rapidly than d

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00718_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACTBeef, pork and lamb roasts were cooked by two 2450 MHz microwave ranges, one operated at 220V (1054W cooking power) and one at 11SV (492W cooking power) and by a conventional gas oven (163 ± 3°C). The only significant effect related to power level of microwave ranges was retention of thiamine, riboflavin and niacin which was less in meat cooked by the microwave 115 V than by the other two methods. There was a trend toward less retention of sodium, chloride, phosphorus and iron in meat cooked by microwaves than by the conventional method. Also, microwave cooking resulted in less formation of free amino acids than conventional cooking but total protein did not differ significantl

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00719_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACTThe effects of mechanical desinewing on yield, proximate analysis and connective tissue content of meat have been examined and its influence on the processing and palatability of cooked salami was evaluated. Mechanical desinewing removed approximately half the connective tissue and reduced the tendency for formation of gelatin pockets in cooked salami. Yields from the desinewer ranged from 71‐87% and correspondingly higher cooking yields were obtained from desinewed meat. Protein and moisture increases were non‐significant whereas the 2.39% change in fat content was, representing a 12.8% decrease. Tenderness and texture of cooked salami were improved by desinew

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00720_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACTElectrodialysis is a unit operation which removes ionic species from a solution through the use of an imposed voltage and ion‐selective membranes. The temperature, flow rate, and composition of the feed, and the applied voltage all influence the rate of ionic transport in electrodialysis systems. The effects of the aforementioned process parameters on the performance of an electrodialysis system were investigated using cottage cheese whey as the process feed. Increasing the flow rate proved to be of little value in decreasing the membrane stack resistance for a given run, but it significantly retarded the rate at which the stack resistance increased in repeated runs. The effect of increasing the total solids concentration of the whey without altering the solute composition was to increase the potential rate of demineralization through an increase in conductivity. Prefractionation of the feed by ultrafiltration enhanced the value of the whey solids by increasing the protein concentration and decreasing the ash concentration. However, the electrodialytic process was less efficient in removing the remaining ash in this case than it was in demineralizing other feed

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00721_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

ABSTRACTIncreases in ultrafiltration rates were obtained by treating whey with acid, calcium‐sequestering agents, or compounds to modify specific protein side chains, or by increasing the ionic strength. The proteins in whey, examined by scanning electron microscopy, underwent marked structural changes corresponding to these changes in the chemical environment. Depending upon the treatment, membrane fouling deposits showed strands, lattice networks, beaded matrixes, helical structures, or protein sheets of varying thickness. The protein forms were affected by the pH, the quantity of reagent added, and the protein functional group which was modified. Fouling of membranes was reduced when formation of protein sheets over the membrane was retarde

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1976.tb00722_41_4.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY