Developing mango powders by foam mat drying technology.

Using mango purée from overripe mangoes to produce powders helped to solve agricultural product stagnation. The research investigates the effect of thickening additives, convection drying, and heat pump drying on bioactive compounds such as total phenolic content (TPC), total flavonoid content (TFC), color, and solubility of the final product. The obtained results showed that the mixture (gum arabic and maltodextrin in the ratio 50:50 w/w) at a concentration of 15% gave a good quality powder texture when dried by hot air convection at 55°C with TPC (21.24 ± 1.58 mg GAE/g dry weight [DW]) and TFC (0.34 ± 0.02 mg QE/g DW), respectively. In addition, the product has a high solubility of 64.35%, with the highest pass-through point of 17.11.

Microbiological Quality of Red Meat Offal Produced at Australian Export Establishments.

A national baseline study of offal hygiene was undertaken at 17 Australian export establishments. A total of 1756 samples of different offal types were analysed for aerobic plate count (APC), generic Escherichia coli, and coliform bacteria. Average APC values varied from 1.51 to 5.26 Log10 CFU/g, depending on species and offal type. The average APC on beef, sheep, lamb, and goat offal was 3.25, 3.38, 3.70, and 2.97 Log10 CFU/g, respectively. There is a small but significant difference in APC on offal sampled frozen (3.26 Log10 CFU/g) and offal sampled fresh (3.73 Log10 CFU/g). Escherichia coli prevalence on beef, sheep, lamb, and goat offal was 15.4%, 28.1%, 17.5%, and 39.3%, respectively. The number of E. coli on positive offal samples ranged from 1.42 to 1.82 Log10 CFU/g. While the quality of some offal approach that of muscle meat, the hygienic quality of red meat offal can be understood by considering the anatomical site from which it is harvested, the usual bacterial levels found at that site, the difficulty in hygienically removing the offal from the carcase, the process prior to packing, and the chilling method used.

Effects of different ageing methods on colour, yield, oxidation and sensory qualities of Australian beef loins consumed in Australia and Japan.

This study investigated the effect of three ageing methods (dry, wet and stepwise wet-then-dry) and ageing time on pH, colour, yield, lipid and protein oxidation and eating quality of beef loins using Meat Standards Australia (MSA) sensory protocols with 900 and 540 consumers in Australia and Japan, respectively. Australian beef loins (Longissimus thoracis et lumborum) at four days post mortem were subjected to wet ageing (boneless; for 7, 21, 35 or 56 days), dry ageing (bone-in; for 35 or 56 days) or a wet-then-dry ageing method (bone-in; 21 days wet ageing followed by 35 days dry ageing). The pH was higher in dry aged than wet aged beef loins (P < .001). Instrumental measurement of surface colour of trimmed dry and wet aged steaks showed significant differences in a*, b* and hue angle. Weight loss was higher in dry aged primals (P < .001), however, total water content was similar among the two ageing methods (P = .934). Retail yield did not differ between 35 and 56 days dry aged primals. Lipid (TBARS) and protein (total carbonyl content) oxidation between the dry and wet aged samples differed depending on the ageing time. When comparing the wet-then-dry and 56 days dry aged samples, only pH and retail yield differed. Australian and Japanese consumers rated dry aged steaks significantly higher (P < .001) than the wet aged counterparts for tenderness, juiciness, flavour, overall liking and weighted palatability scores. The wet-then-dry steaks were also rated higher than the 56 days wet aged steaks for flavour, overall liking and palatability within the Japanese sensory panels. The Japanese consumers also consistently rated all MSA sensory attributes lower (P < .001) than the Australian consumers. The results from this study show dry ageing provides a value adding opportunity for the meat industry in both domestic and export markets.

Low Prevalence of Salmonella and Shiga Toxin-Producing Escherichia coli in Lymph Nodes of Australian Beef Cattle.

Salmonella contamination of ground beef has been viewed as originating from the surface of carcasses. Recent studies have identified lymph nodes as a potential source of Salmonella contamination because these tissues play an active role in containment of pathogens in the live animal and because some lymph nodes are unavoidably present in manufacturing beef trimmings or primal cuts that may be incorporated into ground beef. A survey was conducted of the microbiological status of lymph nodes from Australian cattle at the time of slaughter to determine the prevalence of microbiological contamination. Sets of lymph nodes (n = 197), consisting of the superficial cervical (prescapular), prepectoral, axillary, presternal, popliteal, ischiatic, subiliac (precrural), coxalis, and iliofemoralis (deep inguinal), were collected from five geographically separated Australian abattoirs over a period of 14 months. Samples were tested for the presence of Salmonella spp. and Shiga toxin-producing Escherichia coli by BAX PCR assay. Aerobic plate count, E. coli, and coliforms were enumerated with a lower limit of detection of 80 CFU per node. The observed prevalence of Salmonella within peripheral lymph nodes was 0.48% (7 of 1,464). Two of the seven lymph nodes in which Salmonella organisms were detected came from the same animal. Grass-fed, grain-fed, and cull dairy cattle were all found to have detectable Salmonella in lymph nodes. All Salmonella detections occurred during cooler months of the year. No Shiga toxin-producing E. coli were detected. Aerobic microorganisms were detected above the limit of quantification in 3.2% of nodes (median count 2.24 log per node), and E. coli was detected in 0.8% of nodes (median count 3.05 log per node). The low prevalence of Salmonella and low concentration of aerobic microorganisms in Salmonella-positive lymph nodes of Australian cattle at the time of slaughter suggest that the likelihood of lymph nodes contributing significantly to the presence of Salmonella in ground beef is low.

Mechanisms of effects of complement inhibition in murine collagen-induced arthritis.

OBJECTIVE: To determine the mechanisms of amelioration of collagen-induced arthritis (CIA) in DBA/1J mice by inhibition of complement activation. METHODS: Mice received 2 intradermal injections of bovine type II collagen (CII), on days 0 and 21. From day 21 (immediately after the second injection of CII) through day 35, mice received intraperitoneal injections of either phosphate buffered saline (PBS), a monoclonal mouse antibody to murine C5 (anti-C5 antibody), or the C3 convertase inhibitor Crry-Ig. RESULTS: On days 30 and 32, the clinical disease activity score was lower in mice treated with anti-C5 antibody than in those treated with Crry-Ig. Histopathologic evidence of joint damage was 75% lower in the mice treated with anti-C5 antibody than in those treated with either PBS or Crry-Ig. Spleen cells from mice receiving either form of complement inhibition exhibited decreased CII-stimulated proliferation, whereas increased proliferative responses were exhibited by lymph node cells from mice treated with Crry-Ig. Treatment with anti-C5 antibody decreased production of IgG1 anticollagen antibody, while production of IgG2a antibody was inhibited by both complement inhibitory treatments. CII-stimulated spleen cells from anti-C5-treated mice produced lower levels of tumor necrosis factor alpha (TNFalpha) and interleukin-10 (IL-10) compared with those from mice treated with Crry-Ig. Lower steady-state messenger RNA (mRNA) levels for TNFalpha, interferon-gamma (IFNgamma), IL-18, and IL-6 were observed in the joints of anti-C5-treated mice, and for IFNgamma and IL-6 in mice receiving Crry-Ig, all in comparison with PBS-treated mice. However, mRNA levels for IL-1beta and TNFalpha were lower in the joints after treatment with anti-C5 compared with Crry-Ig. CONCLUSION: These results indicate that inhibition of complement in CIA leads to decreased production of IgG2a antibody and suppressed CII-induced spleen cell proliferation. The greater inhibitory effects on CIA of anti-C5 antibody in comparison with Crry-Ig may be attributable primarily to decreased levels of IL-1beta and TNFalpha mRNA in the joints.