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Infrared thermography (IRT) absorbs infrared radiation and generates images based on the amount of heat generated. It has been used in human medicine for diagnosis of various cancers. This experiment was conducted to determine if IRT had merit for early detection of subclinical mastitis in dairy cows. Milk sample and skin surface temperature (SST) were simultaneously evaluated using the California Mastitis Test (CMT) and IRT for each quarter in 94 dairy cows (49 Brown Swiss and 45 Holstein). Average days in milk (DIM) and milk production were 93 +/- 37 d and 16 +/- 2.2 kg (mean +/- SD) and their ages ranged from 4 to 8 yr. There was a strong correlation between SST and CMT score (r = 0.92). Average SST was 33.19, 34.08, 34.99, and 36.15 degrees C for quarters with the CMT score of 0 (n = 156), +1 (n = 116), +2 (n = 80), and +3 (n = 24), respectively. This association was best described by a linear model as follows: y = 0.94x + 33.17, R(2) = 0.85, where y = SST and x = CMT score. Changes in rectal temperature (RT) due to the CMT score were minor (y = 0.09x + 38.39, R(2) = 0.07, where y = RT and x = average CMT score). In conclusion, RT may not confirm mastitis. However, IRT is sensitive enough to perceive changes in SST in response to varying degrees of severity of the mammary gland infection as reflected by the CMT score, suggesting that as a noninvasive tool, IRT can be employed for screening dairy cows for mastitis.

Lactobacillus sake Lb 706 can release a bacteriocin inhibitory to Listeria monocytogenes. In MRS broth, viable counts decreased rapidly when Lact. sake Lb 706 was added, whereas growth of the listerias was not affected by a bacteriocin-negative variant of the same Lactobacillus strain. Inhibition of L. monocytogenes was also observed in pasteurized minced meat inoculated with Lact. sake Lb 706. The bacteriocin produced is apparently effective in meat. However, the effect of the bacteriocin producer was less evident in minced meat than in broth. In comminuted cured raw pork filled into casings (German-type 'fresh Mettwurst'), L. monocytogenes was able to grow at a pH of 6.3, but addition of Lact. sake Lb 706 prevented the growth of listerias during the first few days after manufacture. At normal pH (5.7) L. monocytogenes did not multiply and addition of Lact. sake Lb 706 reduced viable counts of listerias by about one log cycle. Lactobacillus sake Lb 706 therefore may have some potential as a protective culture in meat products.

Heterocyclic aromatic amines (HCAs) are formed during cooking proteinaceous foods such as meat at temperatures above 150C. Epidemiologic studies have shown that all HCAs are mutagenic, and many are carcinogenic. To date, more than 25 HCAs have been identified at ng/g levels in cooked foods. It is therefore recommended minimizing HCAs occurrence in foods consumed by humans. Thus, more information about them is needed. The purpose of this review is to explain chemistry, formation, precursors, mutagenicity and carcinogenicity, and also levels of HCAs in cooked meats. PRACTICAL APPLICATIONS Heterocyclic aromatic amines (HCAs) are formed during cooking of protein‐rich foods. They are therefore widely consumed by humans. On the basis of results from long‐term animal studies, several HCAs are considered mutagenic and carcinogenic. The competent authorities in most Western countries recommend minimizing HCA occurrence. Thus, it is important to learn more about the formation and inhibition of these compounds in cooked foods. Detailed information about HCAs in cooked meats is briefly presented in this review.

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