Effect of Tumbling and Tumbling Temperature on Surface and Subsurface Contamination of Lactobacillus Plantarum and Residual Nitrite in Cured Pork Shoulder

The effect of intermittent tumbling (up to 18 hr) was compared to a nontumbled treatment at processing temperatures of 3°C and 23°C on tissue surface inoculated with Lactobacillus plantarum. The surface and subsurface number of L. plantarum and the residual nitrite in boneless cured pork shoulder were determined. The L. pluntarum levels were significantly increased (P < 0.05) by tumbling, increased by time (linear, P < 0.01) and by sample location with levels de creasing from nontumbled exudate to surface samples to internal samples. Residual nitrite in cured pork shoulder tumbled intermittently for 18 hr at 23°C was significantly lower (P < 0.01) than in nontumbled tissue. Nitrite level interactions for tumbling time × temperature were highly significant (P < 0.01).     

Effect of Tumbling and Tumbling Time on Quality and Microflora of Dry-Cured Hams

Thirty-two intact hams were utilized to study the effects of tumbling and tumbling time (1 hr continuous, 3 hr intermittent, 6 hr intermittent) on the quality and microflora of intact dry-cured hams. Tumbled hams had higher salt concentrations, lower moisture percentages, and showed more muscle separation and excessive surface drying. Sensory panel scores were similar for all treatments except that 3 hr intermittently tumbled hams had higher salt and lower overall satisfaction scores. Tumbling significantly accelerated salt and nitrite penetration during the Fust 2 wk of curing but had little subsequent effect. Tumbled hams generally had lower microbial counts; however, after aging all hams were of acceptable microbial quality.     

Intermittent Tumbling Affects Quality and Yield in Prerigor Sectioned and Formed Ham

Intermittent tumbling of prerigor porcine muscle maximized quality and yield in sectioned and formed ham when compared to a postrigor tumbled control. Intermittent tumbling affected precook salt-soluble protein, precook water-binding potential, tumbling yield, Instron bind, and sensory panel cohesion and tenderness scores. Tumbling did not affect sensory color distribution scores or cooked yield. A 3 hr intermittent tumbling cycle was adequate for producing prerigor and postrigor cured hams. Intermittent tumbling of prerigor or postrigor cured muscle tissue beyond 3 hr had no additional beneficial effect.     

Rigor Condition, Tumbling and Salt Level Influence on Physical, Chemical and Quality Characteristics of Cured, Boneless Hams

Influence of pre- or post-rigor conditions, short or long-time tumbling and 1.25 or 2.25% salt on the physical and chemical properties, quality and yield of hams were examined. Curing pre-rigor did not inhibit rigor, but long term tumbling slowed rigor development. Cell disruption and salt-soluble proteins extraction were enhanced more by processing pre-rigor than post-rigor. Pre-rigor intermittent tumbling for 18 hr produced a more uniform cured color and a more desirable slice appearance. Cohesiveness was improved by 18 hr intermittent tumbling. Bind strength at 6 hr intermittent tumbling of pre-rigor tissue was equivalent to that of 18 hr intermittent tumbling, suggesting that curing pre-rigor could reduce tumbling time.     

Effects of Tumbling at Various Speeds on Some Characteristics of Restructured Cured Beef

The effects of different tumbling speeds (5, 10, 15, and 20 rpm) during 12 hr intermittent tumbling (10 min/hr) on the characteristics of a restructured cured beef product were studied. There were no differences (P>0.05) among the various treatment means for yield, Hunter color scores, voids between chunks of meat, handling-ability or Allo-Kramer shear values. Meat tumbled at 15 and 20 rpm had higher (P<0.05) Instron values than the meat tumbled at 5 or 10 ‘rpm. However, 20 rpm produced more (P<0.05) extracted protein on the meat surface than 5 rpm. In summary, 5, 10, and 15 rpm produced satisfactory products, although 15 rpm had greater binding ability.     

Effects of Nonvacuum, Vacuum and Nitrogen Back-Flush Tumbling on Various Characteristics of Restructured Cured Beef

Nonvacuum (NV), vacuum (V) or nitrogen back flush (NB) processing conditions during intermittent tumbling (10 min/hr) were compared for effects on the characteristics of restructured cured beef. Meat in a NV atmosphere exhibited higher (P<0.05) cooked yields than either V or NB; also V-tumbled meat had higher yields than the NB atmosphere (P<0.05). Meat tumbled in a NB atmosphere had higher (P<0.05) protein extraction values than meat treated in either V or NV. In summary, meat tumbled at any of the three atmospheres was satisfactory.     

Influence of Tumbling and Phosphate on the Yield, Sensory and Chemical Characteristics of Pork Liver Loaf

Yield, sensory and chemical properties of pork liver loaves manufactured using varying processing treatments (tumbling vs immersion) and phosphate levels (0 vs 6.4%) were studied. Tumbling significantly improved liver cure uptake, total cure and loaf cooked yield when compared to immersion as a processing treatment. Tumbling the livers improved uniformity of internal slice color, external loaf color and external loaf appearance. Loaves made from immersed liver however yielded a more intense liver flavor. Increasing moisture levels were likewise noted for tumbled livers. Addition of phosphate resulted in an increase in liver cure uptake, total cure and loaf cooked yield for the tumbled livers. Phosphate however had no effect on these parameters for livers which were immersed. Addition of phosphate improved slice cohesiveness and internal slice consistency. An increase in the percent ash was the only chemical parameter altered significantly through the addition of phosphate.     

Effect of tumbling time and cooking temperature on quality attributes of cooked ham

This study evaluates effect of tumbling time and cooking temperature on cooking rate, cooking loss (CL), colour, water activity and water‐holding capacity of cooked restructured ham rolls. In experiment were investigated three tumbling times (2, 4 and 6 h) at constant temperature (+4 °C) and three cooking temperatures (76, 86 and 96 °C). It was observed that CL decreased (P < 0.01) from 5.41% to 3.22% with tumbling time (2 h vs. 6 h) but increased (P < 0.01) from 2.35% to 7.25% along with cooking temperature (76 °C vs. 96 °C). In contrast, pH value increased (P < 0.01) from 6.18 to 6.24 with tumbling time (2 h vs. 6 h) but decreased (P < 0.01) from 6.22 to 6.17 along with cooking temperature (76 °C vs. 96 °C). In addition, high temperature had higher efficiency for thermal lethality than low temperature (F₀ values were 19 and 92 min at 96 and 76 °C, respectively). Intermediate tumbling (4 h) and cooking (86 °C) could be preferential.     

Effect of Continuous Massaging on Bind, Yield, and Color of Hams

Boneless closely trimmed hams were randomly assigned to six treatment groups to determine the effect of massaging time (4, 8, 12, 16, 20, and 24 hr) on selected ham characteristics. All hams were stitch pumped 30% above green boneless weight with a pickle containing water, salt, sugar, sodium tripolyphosphate, sodium erythorbate, and sodium nitrite. Pickled hams were massaged continuously (30 mm forward-30 mm reverse cycle) at 5 rpm in a 4°C cooler. Hams were stuffed into size 7 fibrous casings and processed in a smokehouse to an internal temperature of 67°C. Results showed that a massaging time increased there were significant (P < 0.01) increases in bind, color uniformity, color intensity, and moisture retention.     

Reduction or Replacement of Sodium Chloride in a Tumbled Ham Product

Public concern over excess sodium in the diet has prompted investigation of sodium replacement in tumbled ham. Salt treatments consisted of a control (100% NaCl) and 50% or 100% ionic strength replacement with either KCl or MgCl₂. Protein extraction was monitored during the 8 hr, discontinuous tumbling cycle, and reached a peak within 6 hr for all salt treatments. Control hams had the best overall sensory scores, while KCl/NaCl treatment gave the best physical bind and acceptable sensory scores (P<0.05). Treatment with MgCl₂ gave the lowest bind and sensory scores (P<0.05). Partial replacement of Nacl ionic strength with 50% or less of KCl in tumbled ham can be accomplished while maintaining acceptable sensory and physical attributes.     

Cure Levels, Processing Methods and Meat Source Effects on Low-fat Frankfurters

Frankfurters were manufactured from lean meats (100% beef and 50:50 beef-pork) to contain reduced levels of fat (about 1.3%). A curing solutibn was added to yield 160% of fresh meat weight. Three processing methods, coarse ground tumbled, fine ground tumbled and fine ground emulsified were used. All products were cooked in live steam to 71°C internal temperature. Product yields, penetrometer values, color, chemical composition, caloric content and added water were evaluated. Emulsified frankfurters from 50:50 beef-pork mixtures at 160% cure had texture similar to conventional product as well as increased (P<0.05) yields, acceptable color and 74% fewer calories.     

Quality characteristics of chunked and formed hams from pale,average and dark muscles were improved using an ammonium hydroxide curing solution

Cooking yield, cooked pH, purge loss, moisture, lipid oxidation, external and internal color, break strength and elongation distance were assessed for pale (PALE), average (AVG) and dark (DARK) inside hams injected with either a control cure solution (CON) or BPI-processing technology cure solution (BPT). Following enhancement, muscles were chunked, vacuum tumbled, smoked and cooked to 66 °C. Cooked ham pH was 6.49 for DARK, 6.40 for AVG, and 6.30 for PALE, respectively (P < 0.0001). Cooked pH was higher (P < .0001) for BPT than CON. Cooked ham moisture content was higher (P < 0.0001) for BPT hams than CON hams (74.83 vs. 74.11%) but BPT did not significantly influence cooking yield or lipid oxidation. Consumers (n = 150) of diverse demographics rated hams for appearance and taste. Results indicated that BPI-processing technology improved visual appearance of hams made from pale, average, and dark muscles and improved the eating quality of hams made from pale muscles.     

Bioassay Analysis of Dry-Cured Ham Processed to Affect Trichinella spiralis

Effects of curing time and temperature to destroy Trichinella spiralis in dry-cured hams were evaluated. Five muscle groups from small, medium and large, short-cure hams and large, bag-cure hams were subjected to a digestion technique to determine the number of spiralis larvae. Trichinae in small hams held at 10°C for 90 days, in medium hams at 23.9 and 32.2°C for 35 and 11 days, and in large hams at 10 and 23.9°C for 90 and 35 days, respectively, were rendered non-infective. Medium hams contained a number of trichinae after 90 days at 10°C. Bag-cure hams aged at 23.9°C for 35 days were free of trichinae. Results could indicate insufficient aging time at 10°C for medium hams and the need for reviewing current USDA-FSIS regulations for the destruction of T. spiralis.     

Oligopeptides and free amino acids in Parma hams of known cathepsin B activity

Sixteen Parma hams were manufactured following regular standard procedures up to the 13th month of processing and then divided into two groups according to established levels of cathepsin B activity in fresh hams. Each group was selected in order to include the same number of hams with low or high cathepsin B activity. The two groups were further split to be kept for an additional month at two different temperatures (18 and 26 °C) and then analysed for proximate composition, free amino acids and oligopeptides (MW<500 Da). All hams were analysed by sensory analysis (panel test) to be scored for saltiness, bitterness and the flavour of “ageing”. Fresh hams with higher cathepsin B activity were shown by means of two-way ANOVA to yield dry-cured hams more proteolysed (P<0.01), while the higher temperature of the final ageing period seemed to play a major role in lowering ham dryness. Bitterness was particularly well perceived in most proteolysed hams and it was significantly related to the higher amounts of lipophilic amino acids and lipophilic oligopeptides (identified by mass spectrometry), in agreement with the literature. Thus, the endopeptidase activity in fresh hams, together with the presence of specific lipophilic amino acids and oligopeptides in dry-cured hams, can be regarded as a molecular marker of bitter taste development.     

牛肉真空滚揉条件对白卤牛肉品质和出成率的影响

为探讨真空滚揉技术在卤牛肉加工中的应用,论文分析了牛肉真空滚揉时真空度、转速、滚揉时间、载荷量、原料初始温度和静腌时间对白卤牛肉主要成分、感官品质、色度、质构特性及出成率的影响。将初始温度为0～5℃的牛肉、3.3%食盐和0.1%花椒放入滚揉器中,载荷量60%,真空度6 kPa,4 r/min滚揉15 min,静置10 min;加入1.3%洋葱汁、1.2%香芹汁、2.5%胡萝卜汁和1.8%二锅头,重复滚揉1次;出料后0～5℃静腌12h。采用上述操作条件腌制的牛肉加工的白卤牛肉的品质和出成率均较高。     

Effect of Thermal Processing on the Survival of Foot-and-Mouth Disease Virus in Ground Meat

Foot-and-mouth disease virus was examined for its stability during cooking in tissues from infected cattle. The 0₁ (CANEFA 2) serotype of foot-and-mouth disease virus survived in lymph node tissues after heating for 2 hr at 69°C, for 1 hr but not for 2 hr at 82°C, and for 15 min but not for 0.5 hr at 90°C. Incorporation of 1% NaCl into suspensions of infected lymph nodes enhanced viral survival after heating for 0.5 hr but not for 1 hr at 90°C. The virus did not survive in either ground beef or meatballs contaminated with infected lymph node tissue, when processed to internal temperatures of 93.3, 96.1 or 98.8°C using commercial thermal processing procedures. Accurate temperature measurements were achieved with a temperature sensitive indicator disc developed in this study.     

Chitosan Nanoparticle Penetration into Shrimp Muscle and its Effects on the Microbial Quality

Chitosan (CH) and chitosan-sodium tripolyphosphate (CH-TPP) solutions were produced with and without sonication and ultra-shearing. The CH and CH-TPP particles and solutions were evaluated for physicochemical properties, and fluorescently labeled particle penetration into shrimp muscle tissue through vacuum tumbling was observed. Two solutions were prepared: (1) a 0.5 % CH solution in 1 % acetic acid and (2) a CH-TPP solution, prepared by adding 0.167 % sodium tripolyphosphate to the CH solution, instantly forming CH-TPP nanoparticles through ionotropic gelation. Untreated shrimp meat and shrimp meat vacuum tumbled with CH, CH-TPP, acetic acid, sodium tripolyphosphate, and distilled water solutions were analyzed for aerobic plate counts for 24 days of refrigerated storage at 4 °C. Processing with sonication and ultra-shearing reduced the particle sizes of CH and CH-TPP nanoparticles and the molecular weight of CH. It was observed that after processing, fluorescently labeled CH and CH-TPP nanoparticles could penetrate inside of and attach to shrimp muscle tissues through vacuum tumbling. At 24 days of refrigerated storage, shrimp vacuum tumbled with processed CH solution had the lowest aerobic plate counts of all treatments and it was the only treatment to have unchanged microbial quality throughout the entire storage time. Vacuum tumbling with sonicated and ultra-sheared CH solution enhanced particle penetration into shrimp and inhibited microbial growth during refrigerated storage.     

Incidence and principal sources of Listeria spp. and Listeria monocytogenes contamination in processed meats and a meat processing plant

The occurrence and distribution of listeriae in a meat processing plant was studied to determine the major sources and routes of contamination. Listeria monocytogenes and other Listeria spp. were isolated from 51% and 49% of samples of frozen raw meat taken from several incoming lots. Turkey necks and breasts, pork trimmings and lard were the principal sources of initial contamination. As a consequence, listeriae colonized certain processing sites where raw materials were handled and hygienic conditions were not strict. Mainly tumbled meats were contaminated heavily during tumbling as the need to operate tumblers continuously did not enable their proper cleaning and disinfection on a daily basis. Also the use of mechanically deboned turkey-neck meat in cooked sausages raised contamination at a pre-cooking stage. Listeriae survived in tumbled meats cooked in boilers at core temperatures below 70°C, and in country-style sausages heated to 65–68°C. In contrast, listeriae were killed in oven-cooked tumbled meats and emulsion-type sausages heated to 72–75°C, and in fully ripened salamis. Heat survivors appeared to be the main cause of post-process contamination as spreading of listeriae in the cutting room was restricted to processing lines where precontaminated meat products were handled. The possible reasons leading to heat survival of listeriae and the measures taken to control the problem were discussed.     

Influence of Pre-Rigor Processing, Mechanical Tenderization, Tumbling Method and Processing Time on the Quality and Yield of Ham

Eight market weight hogs with similar genetic and management background were conventionally slaughtered with the resulting sixteen pork carcass sides randomly assigned to treatments. Four treatments at 2 levels each (2⁴ factorial design) included muscle condition [pre-rigor (hot) or post-rigor (chilled)], mechanical knife blade tenderization [no tenderization or tenderization], vacuum tumbling [continuous or intermittent], and the processing delay time between vacuum tumbling and further processing [no delay time or 20-hr delay]. Results indicated that pre-rigor processed meat tissue exhibited higher pH, water-holding capacity (WHC), and cooked yield characteristics. Mechanical knife blade tenderization consistently increased protein content of the uncooked meat exudate, cooked yield, and palatability characteristics. Tumbling method and processing time had little influence on either uncooked or cooked meat characteristics.     

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.