SAFETY OF IRISH BEEF – CONCERNS, AWARENESS AND KNOWLEDGE OF IRISH CONSUMERS

A survey of Irish consumers examined their concerns for the safety of food, their level of knowledge of safe food practices and their awareness of institutional structures to ensure the safety of Irish beef. Sixty-four percent of the sample expressed concern for the safety of food. Concerns cited include freshness of food, BSE/CJD, antibiotic residue, hygiene standards and bacteria. They perceive many causes of food poisoning and their level of awareness of pathogens varies, depending on the pathogen. The level of knowledge of safe food practice in cooking was good. However, it was lower for food storage practices. Males and those with lower levels of education were less likely to be aware of adequate food safety procedures and need to be the focus of educational programs on safe food handling. As less than half the sample (49%) was aware of institutional structures and 32% of schemes that ensure the safety of Irish beef, it is concluded that it is imperative to more clearly communicate to the public the assurances of any scheme set up. There is also a need to increase awareness level of the bacteria Campylobacter.     

IDENTIFICATION AND ACCEPTANCE OF LAMB VERSUS BEEF AND PORK BY CONSUMERS AND EXPERIENCED SENSORY PANELISTS

Lamb, beef, and pork patties containing ≈ 21% fat were pan-fried to 71C and evaluated by consumers (n=71) and experienced laboratory sensory panelists (n=12) to determine to what extent panelists could correctly identify the species and to document the probable basis of their identification. When six samples (the first three samples representing the first servings of the three species and the next three representing the second servings) were served one at a time, 59%, 49%, and 32% of consumer panelists correctly identified both servings of lamb, beef, and pork, respectively, compared to 67%, 50%, and 33%, respectively, by experienced laboratory panelists. Sensory attribute scores and correlation data on correctly identified samples indicated that flavor intensity of lamb and pork patties did not have positive effects on their overall palatability, whereas flavor intensity of beef patties had positive effects. Lamb patties were rated most intense in flavor and lowest in overall palatability.     

ACCELERATED RESTRUCTURING OF BEEF

Restructured steaks manufactured by two comminution methods from prerigor electrically stimulated (PES) beef, nonstimulated counterparts (NES) and postrigor non-electrically stimulated (C) samples were compared. After frozen storage for 0,14, and 42 days, samples were subjectively evaluated for appearance and palatability traits. Objective measurements included Hunter Color, TBA, Kramer, and Instron values. Electrical stimulation reduced peak force but did not consistently improve sensory panel scores. Comminution method did not consistently affect any traits. Results suggested that subjective appearance was affected more by storage time than other treatments and that prerigor beef may be effectively utilized in restructured beef without affecting palatability traits.     

TEXTURAL CHARACTERISTICS OF BEEF MUSCLES

Uniaxial compression tests were performed on raw and cooked meat samples prepared from five muscles excised from a single beef hindquarter. The greatest variation of mechanical properties was across the muscle (lateral to medial) rather than along the muscle (origin to insertion). Active muscles showed greater variation and were generally tougher than inactive muscles. By carefully following regions of similar characteristics from raw to cooked slices, linear regression curves for raw vs cooked beef were obtained having correlation coefficients averaging 0.87.     

HIGH-TEMPERATURE CONDITIONING OF HOT-BONED BEEF SUBPRIMALS

The right sides of 18 carcasses were randomly assigned to one of two treatments: (1) hot-boned at 2 h postmortem, vacuum packaged and high temperature conditioned at 37 C for 3 h (HTC) or (2) electrically stimulated, hot-boned 2 h postmortem, vacuum packaged and high temperature conditioned at 37 C for 3 h (ES + HTC). The left sides served as controls being boned 48 h postmortem. The longissimus (LD), semitendinosus (ST) and semimembranosus (SM) muscles were examined for percentage thaw loss, cook loss, total weight loss and sensory attributes. HTC increased the tenderness of LD samples, had no effect on SM samples and decreased the tenderness of ST samples. Electrical stimulation of carcasses, prior to boning and high temperature conditioning, had little effect over and above high temperature conditioning alone but did reduce variability. In LD samples, ES improved the sensory attributes whereas in ST samples, ES tended to decrease sensory attributes.     

RETAIL APPEARANCE OF ELECTRICALLY STIMULATED BEEF

Top round steaks (adductor) and ground beef from the top round were obtained from both sides of ten U.S. Choice carcasses. Left sides were electrically stimulated (ES) with 17 impulses (1.8 set duration, 1.8 set interval) of 550 volts of alternating current at 5 amps. Steaks and ground beef from top rounds from nonstimulated right sides served as control (CON) samples. Steaks and ground beef were displayed under simulated retail conditions for 4 and 3 days, respectively. Steaks were weighed prior to and at the termination of the display interval to determine percentage weight loss. Samples for microbiological evaluation were obtained prior to and at the termination of the display interval. No significant differences were observed for muscle color, surface discoloration or overall appearance for samples of ground beef at any retail display interval. With one exception, muscle color was brighter and surface discoloration was reduced for round steaks from ES sides. Few significant differences in overall appearance were observed between ES and CON samples during the display period. No significant differences between ES and CON samples were observed for bacterial counts either initially or at the termination of the display period for either steaks or ground beef samples. Percentage weight loss was not significantly different between ES and CON steaks. These data suggest that electrical stimulation may enhance, and certainly does not detract from, the appearance of round steaks displayed under retail market conditions.     

EFFECT OF SPLEEN IN RESTRUCTURED BEEF

Boneless beef chucks were converted to restructured beef steaks and formulated with 1% NaCl and 0.25% sodium tripolyphosphate (STP). Experimental treatments included (1) control-frozen, (2) control-5 days storage at 0°C, (3) 1% spleen pulp-frozen and (4) 1% spleen pulp-5 days storage at 0°C. Treatments 2 and 4 were evaluated only after storage for 5 days; whereas, treatments 1 and 3 were studied at 5 and 70 days. Spleen pulp enhanced (P<0.05) color development during frozen storage for a short period but offered no (P>0.05) contribution to color preservation during prolonged storage. Visual color and overall appearance were affected more by storage time and conditions than by the addition of spleen pulp. Spleen pulp had no effect (P>0.05) on product cohesiveness, texture, tenderness and flavor of frozen restructured beef steaks but improved the tenderness of unfrozen samples.     

INSTRUMENTAL MULTIPLE TEXTURE PROFILE ANALYSIS OF COOKED GROUND BEEF PATTIES AND SMOKED BEEF

An instrumental texture profile for cooked hamburger patties was obtained by repeated tests on the same samples in the wire extrusion cell of the Ottawa Texture Measuring System. The correlation between sensory and instrumental texture profile parameters was increased when two or more instrument test cycles were applied to each sample in the same test cell. Tests with smoked beef and hamburger patties showed that the change in textural characteristics with repeated cycles depended on the texture of the food.