Biologically active polyamines in pig kidneys and spleen: Content after slaughter and changes during cold storage and cooking

Polyamines putrescine, spermidine (SPD) and spermine (SPM) were determined as dansyl derivatives using an HPLC method. Distribution of SPD and SPM in pair kidneys was homogenous. The mean SPD and SPM contents in pig kidneys 24 h after slaughter were 9.39 ± 3.35 and 53.1 ± 14.0 mg kg⁻¹, respectively with no significant differences between barrows and gilts. Putrescine content was below the detection limit of 1.2 mg kg⁻¹. In kidneys stored aerobically or vacuum-packaged at 2–3 °C for 7 and 21 days, respectively, SPD and SPM decreased significantly. Stewing decreased both polyamines more extensively in kidneys processed on day-1 after slaughter than on day-7 after storage at 2–3 °C. The mean SPD and SPM in 10 spleens 24 h after slaughter were 36.7 ± 5.70 and 34.0 ± 7.64 mg kg⁻¹, respectively. Thus, both pork kidney and spleen are foods with a high level of SPM and SPD.     

Content of polyamines in beef and pork after animal slaughtering

Dietary polyamines putrescine (PUT), spermidine (SPD) and spermine (SPM) participate in an array of important human physiological roles, including tumour growth. Physicians and dieticians thus need reliable information on polyamine contents in foods. However, data for both fresh and processed beef and pork are limited. We therefore, determined the initial content of the polyamines, 24 h after slaughtering, in sirloin and rump of 63 young bulls and in loin and leg of 27 pigs of both genders. Polyamines were determined as N-benzamides by micellar electrokinetic capillary chromatography (MECC). PUT and SPD contents in most of the meat samples were negligible. Mean SPM contents were about 22±6 mg kg⁻¹ in sirloin and rump. No significant correlations at P<0.05 were found between the SPM contents in sirloin and rump, likewise between SPM contents and the age and between live weight and type of the efficiency of the bulls. Mean SPM contents in loin and legs of barrows were 26.1±7.0 and 28.4±8.5 mg kg⁻¹, respectively, while the corresponding values in gilts were 22.3±10.6 and 18.3±9.3 mg kg⁻¹.Between the genders the difference in SPM contents in the legs was significant. SPM contents relatively vary widely within the individual kinds of meat, which complicates application of the results for the controlled human nutrition.     

Contents of polyamines in selected foods

Dietary polyamines, putrescine, spermidine and spermine, participate in many biochemical processes, mainly in cell proliferation and differentiation. Polyamines were determined as N-benzamides by micellar electrokinetic capillary chromatography in 153 samples of 21 foods, mostly culinary processed. Very low putrescine contents were observed in processed meats, pork liver and kidney, while the highest mean contents exceeded 55 mg kg⁻¹ in stewed green pea, grapefruit and fresh green pepper. Higher spermine than spermidine contents were typical for foods of animal origin, while the opposite was observed in plant products. Mean spermidine contents, exceeding 20 mg kg⁻¹, were found in dry soybean, stewed green pea, yellow pea puree and roasted chicken breast. Roasted chicken breast, stewed pork kidney, roasted pork liver and roasted pork neck had mean spermine contents above the same level. Polyamine content varies widely within individual food items, what makes application of the results by dietitians rather difficult.     

Changes in the content of biologically active polyamines during storage and cooking of pig liver

Dietary polyamines putrescine (PUT), spermidine (SPD) and spermine (SPM) participate in numerous human physiological processes, including tumour growth. Eight experiments with pig liver were carried out. In two, livers were stored at -18°C for 168 days, in four, livers were stored aerobically (AE), vacuum-packaged (VP) and packaged in a modified atmosphere (MO; 70% N(2) and 30% CO(2), v/v) at +2°C for 9, 21 and 21 days, respectively, and in two, the effects of four cooking treatments were tested. Polyamines were determined as dansyl derivatives using an HPLC method. Distribution of both SPD and SPM in the four main liver lobes was homogenous. The initial SPD and SPM contents in 14 livers 24h after slaughter were 23.3±6.7 and 94.5±19.6mgkg(-1), respectively. The putrescine content was below the limit of detection. The content of SPD and SPM decreased during frozen-storage to about 70% of the initial values. On day-9 of storage, mean SPD and SPM contents decreased to about 85% of the initial values in livers stored in MO and to about 75-80% in AE and VP at 2°C. The decrease continued more extensively in VP than in MO. PUT was detected from day-15 of VP and MO storage. There was a significant decrease in SPD and SPM, to about 70-60% of the initial content during cooking.     

Levels of heavy metals in candy packages and candies likely to be consumed by small children

Ninety two samples of child-consumed candies and candy packages were analyzed for seven heavy metals. Lead (Pb) was detected at concentrations of 110.3–6394.1 mg kg⁻¹ in ten of 92 candy packages. The directive factor of Pb contamination had originated in the lead-based ink of the outer cover. Particularly, Pb was detected at high concentrations in case of green- or yellow-colored packages. Chromium (Cr) was detected at high concentrations in cases where Pb was also detected at high concentrations, and the Cr levels ranged from 136.9 mg kg⁻¹ to 1429.3 mg kg⁻¹ in seven of the 92 candy packages. Hexavalent chromium [Cr(VI)] was detected at 87–105.0% of the total Cr in polypropylene-coated wrappers with printed outer covers. The migration of Cr(VI) increased with elution time up to 0.20 μg (cm²)⁻¹ for 30 days in basic (pH 10.0) solution; however, there were no migrations in acidic (pH 4.0) and neutral (pH 7.0) solutions. The migration of Pb increased with elution time up to 0.65 μg (cm²)⁻¹ and 0.28 μg (cm²)⁻¹ in basic (pH 10.0) and acidic (pH 4.0) solutions, respectively. However, any migration was hardly observed in neutral (pH 7.0) solution.     

Biologically active polyamines in beef, pork and meat products: A review

Dietary polyamines (PAs) putrescine (PUT), spermidine (SPD) and spermine (SPM) participate in an array of roles in human metabolism. Nevertheless, under some physiological conditions they can be undesirable. Meat and meat products are among important sources of PAs in human nutrition, mainly of SPM. The usual contents of PUT, SPD and SPM in fresh beef and pork are <2, <5 and 20-40mgkg(-1), respectively. Current information on changes of PAs during meat storage corresponds with PUT formation by bacterial activity mainly of pseudomonads and Enterobacteriaceae. However, data on SPD and SPM changes during meat chill-storage have been inconsistent. Culinary processing of meat probably does not change SPD and SPM levels. PUT can be formed in different meat products in relation to the microbial population of the raw materials used and the hygienic level of manufacturing process. SPD and SPM contents seem to remain stable during processing of non-fermented meat products or decrease during dry-cured ham ripening. PUT contents increase commonly to 60-140mgkg(-1) in dry spontaneously fermented sausages, however, contents up to several hundreds mgkg(-1) are not extraordinary. Starter cultures are usually able to decrease PUT formation considerably. SPD and SPM contents in dry fermented sausages are comparable with levels typical for fresh meat. Data on SPD and SPM changes during ripening and storage are inconsistent. A decrease of the both polyamines during a storage period has been usually reported.     

Evaluation of S-residues in grains and grain fractions fumigated with S-labelled carbonyl sulfide

³⁵S-labelled carbonyl sulfide (CO³⁵S) was used to measure the amount of sorbed ³⁵S residues and converted ³⁵S residues in grains and grain fractions after fumigation with CO³⁵S. Hard wheat, soft wheat, paddy rice, brown rice, polished rice, sorghum, maize, canola, barley, oats and peas were exposed for 4 days to 50 mg L⁻¹ of CO³⁵S with a total radioactivity of 20 mCi. After exposure, the samples were aired. The levels of ³⁵S residues varied with extraction solvent, e.g. 0.003–0.02 mg (COS equivalents) kg⁻¹ (grain) in chloroform extractions and 0.09–0.38 mg kg⁻¹ in water extractions. More than 90% of ³⁵S (COS equivalents) residues were in the water extractions. The total radioactivity determined by scanning radiation images (fluorescent image) of extractions and sectioned commodities ranged from 0.1 to 0.4 mg kg⁻¹. The radiation image shows that more than 90% of ³⁵S residues were located or distributed in the embryo, testa, pericarp and husk, and that the ³⁵S was still slowly desorbing from grains after 2 days aeration.     

Vascular effects and antihypertensive properties of κ-casein macropeptide

The blood-pressure-lowering effect of bovine κ-casein macropeptide (CMP), previously reported to exhibit a modest angiotensin-converting enzyme (ACE)-inhibitory activity in vitro, was evaluated in spontaneously hypertensive rats (SHR). The oral administration of CMP (150 mg kg⁻¹) significantly reduced the systolic blood pressure (SBP) of SHR. The antihypertensive action was more pronounced when CMP was treated with trypsin. The sequence MAIPPKK, identified in the tryptic hydrolysate of bovine CMP, significantly reduced blood pressure at a dose of 10 mg kg⁻¹. The CMP and its tryptic peptides induced relaxation of endothelium-intact aortic rings. The sequence MAIPPKK also evoked a significant relaxation effect; however, the shorter sequence MAIPPK and the strong ACE-inhibitory tripeptide IPP exhibited a vascular relaxing effect lower than 10%. The implications of vascular relaxing mechanisms, as well as the possibility that the tripeptide IPP is at least partially responsible for the antihypertensive effects of CMP, are discussed.     

Biogenic amines and polyamines in liver,kidney and spleen of roe deer and European brown hare

Cadaverine (CAD), histamine (HIS), tyramine (TYR) and the polyamines putrescine (PUT), spermidine (SPD) and spermine (SPM) were determined in liver, kidney and spleen of hunted roe deer (n = 39) and European brown hare (n = 20) 3 and 6 h post mortem, respectively. Median concentrations (mg/kg fresh weight) of CAD and TYR were <5 mg/kg for organs of both species, whereas median HIS concentrations were higher in spleen (14.6 and 11.6 mg/kg for hare and roe deer, respectively) and lowest in liver. Maximum PUT concentration was 72.9 mg/kg, but median values were ≤7.8 mg/kg. Mean SPD concentrations were 8.5, 10.7 and 42.9 mg/kg for liver, kidney and spleen of roe deer, and 37.2, 24.4 and 52.0 mg/kg for hare. Mean SPM concentrations were higher (94.6, 79.9, 102.2 and 111.2, 82.8, 91.1 mg/kg, respectively). SPM concentrations in the organs of the male roe deer were significantly higher than in those of females. SPM:SPD ratios (weight base) were in the order of 2:1 for spleen, and higher for liver and kidney. SPM and SPD were correlated significantly (r = 0.42–0.47). Although variations of polyamine concentrations are partially associated with species, organ, age and gender, the relative contribution of individual factors deserves further study.     

Fumigation trial on direct application of liquid carbonyl sulphide to wheat in a 2500 t concrete silo

Wheat (Australian Standard White) with a moisture content of 10.2% was fumigated with carbonyl sulphide (COS) at a calculated application rate of 24.14 g m⁻³, in a sealed concrete vertical silo (3512 m³, 2500 t wheat) located at Nevertire, NSW, Australia. The COS was applied as a liquid via the top of the silo and released 2 m below the grain surface. The application of 84.5 kg of COS was completed within 30 min. With 2 h of recirculation using a 0.4 kW fan, the in-silo concentrations of COS achieved equilibrium with a concentration variation less than 5% of the mean. After a two-day exposure period, the COS concentration in the silo remained at 29 g m⁻³. The concentration×time product (Ct) was then 1900 g h m⁻³, and this achieved complete kill of all life stages of mixed-age cultures of Sitophilus oryzae, Rhyzopertha dominica, Tribolium castaneum and Trogoderma variabile. After 2-days exposure, the silo was aired overnight with an aeration fan (25 kW) resulting in a COS in-silo concentration of below 4 ppm. This is 2.5 times lower than the Australian Experimental Threshold Limit Value (TLV) of 10 ppm. Residues of COS in the wheat declined to below the Australian Experimental Maximum Residue Limit (MRL) of 0.2 mg kg⁻¹ after overnight aeration. The COS was not detected in any outloading samples at concentrations above the detection limit (0.05 mg kg⁻¹). The workspace and environmental levels of COS were monitored during application, fumigation, aeration and outloading. The levels of COS and hydrogen sulphide (H₂S) were less than the detection limit of 0.1 ppm, which was 100 times lower than the TLV of 10 ppm. The treatment with COS had no affect on the wheat germination and seed colour when compared with untreated controls. Oil quality tests showed that COS had no effect on total lipid (made from treated wheat) content or the lipid colour.     

The effect of ractopamine on myofibre distribution and morphology and their relation to meat quality in swine

One hundred and twenty-eight purebred Lacombe pigs (equal number of barrows and gilts) were assigned to one of four treatments at 64 kg and fed a commercial grower-finisher diet ad libitum to which ractopamine (RAC) was incorporated (0, 10, 15 or 20 mg kg⁻¹). Pigs were slaughtered at 100 kg. Histological samples were collected from the semimembranosus (SM) and the psoas major (PM) muscles from the 0 and 20 mg kg⁻¹ RAC groups. Meat quality and muscle composition data were collected for all pigs. A significant 3-way interaction for muscle weight involving treatment, muscle and gender (P = 0·01) indicated that for the SM, gilts appeared to respond to RAC at a lower level of incorporation (10 mg kg⁻¹) than barrows. Despite these differences in response at the gross muscle level, responses were similar at the cellular level for both muscles. The proportion of red fibres did not change (P = 0·21), the proportion of intermediate fibres decreased (P = 0·01) and the proportion of white muscle fibres increased (P = 0·02) in the mg kg⁻¹ RAC group compared to the controls. In addition, when compared to controls, average fibre diameters in the 20 mg kg⁻¹ RAC group remained constant in the red fibres, and increased significantly in both the intermediate and white fibres (P = 0·01 and 0·02, respectively). Over both muscles Kramer Press values were significantly higher (P = 0·030 in the RAC-fed pigs than in the controls. Incorporation of RAC into the diet did not result in any changes to crude protein or total and soluble hydroxyproline levels. Crude fat tended to increase in the 15 mg kg⁻¹ RAC treatment in the SM and decreased in the 20 mg kg⁻¹ RAC treatment in the PM. The shift in fibre type, and the associated changes in fibre size, may contribute to the increased shear values found in RAC-fed pigs.     

Contents of biologically active polyamines in chicken meat,liver, heart and skin after slaughter and their changes during meat storage and cooking

Dietary polyamines, putrescine, spermidine (SPD) and spermine (SPM), participate in an array of important physiological roles, including tumour growth. Thus, reliable information on polyamine content in foods has been needed. We therefore determined polyamine contents in chilled chicken meat and giblets (n = 20) and skin (n = 10) 24 h after slaughter. The polyamines were determined, after extraction with perchloric acid, as dansyl derivatives, using an HPLC method. Mean SPD values were 4.8, 10.2, 11.4, 48.7 and 12.1 mg kg⁻¹ and SPM values were 36.8, 38.0, 24.3, 133 and 82.7 mg kg⁻¹ in breast, thigh, skin, liver and heart, respectively. Significant statistical correlations between SPD and SPM contents were observed in breast, thigh, skin and liver, whereas correlations were insignificant in heart. An increase of SPD and SPM was apparent in breasts and thighs stored at −18 °C for 6 months; however, it was significant only for SPM in thighs. The losses of both SPD and SPM were statistically insignificant during storage of aerobically packaged breasts up to 9 days at +2 °C. A significant decrease of SPM to about 60% of the initial contents was observed in both vacuum-packaged and in modified atmosphere (20% CO₂ and 80% O₂)-stored breasts on day 21 at +2 °C. For both SPD and SPM, roasting, grilling and frying of fresh breasts caused losses of about 40–60% of the initial contents (higher than boiling and stewing). Similarly, losses of SPM, due to roasting of breasts frozen for 3 or 6 months, were higher than those caused by stewing. Putrescine was detected only sporadically and at levels close to the detection limit of 1.0 mg kg⁻¹ (fresh matter).     

Aflatoxins in stored maize and rice grains in Liaoning Province, China

Aflatoxin contamination and its relationship to storage length in stored maize and rice in Liaoning Province, northeastern China, was investigated. Aflatoxins in 110 samples collected from an area of 14.68 million km² covering storage length from 1 yr to over 10 yr were determined by high-performance liquid chromatography with fluorescence detection. The results showed that almost all samples collected contained aflatoxins. The average contents in maize, whole grain rice and brown rice were found to be 0.99, 3.87 and 0.88 μg kg⁻¹, respectively. Three-fourths of the total aflatoxins in whole grain rice (3.87 μg kg⁻¹) could be removed by dehusking to as low as 0.88 μg kg⁻¹ in brown rice. No significant aflatoxin increase was observed in whole grain rice and brown rice over a 10-yr storage period. In maize, the amount of aflatoxins was significantly higher in 2-yr than 1-yr sample. Aflatoxin G₁ was detected as the major type of aflatoxin in over 40% of all stored grain samples tested and over 92% of rice samples examined. The aflatoxin content in maize and rice is much lower than the regulated maximum amount allowed in foodstuffs in China and other countries. We concluded that these grains are safe for human and livestock consumption and for trading.     

Changes in the content of biologically active polyamines during pork loin storage and culinary treatments

Dietary polyamines putrescine (PUT), spermidine (SPD) and spermine (SPM) participate in numerous human physiological processes, including tumour growth. Physicians and dieticians thus need reliable information on their contents in foods. However, data for processed meat are rather limited. Eight experiments with pork loin were therefore carried out. Loins were stored at −18 °C for 168 days in three experiments, in next three ones pork was stored aerobically, vacuum-packaged and packaged in a modified atmosphere (70% N₂ and 30% CO₂, v/v) at +2 °C for 9, 21 and 21 days, respectively. The effects of five usual culinary treatments were tested in two experiments. The polyamines were determined as dansyl derivatives using a HPLC method. Only SPM was determined at levels 20.3–25.2 mg kg⁻¹ in fresh loins; PUT and SPD contents were below the detection limits. SPM content slightly, but significantly (P < 0.05) increased during frozen storage, while it mildly and insignificantly (P > 0.05) decreased during all three variants of cold storage. SPM losses of about 40% of the initial content were observed during boiling, stewing, pan-roasting without oil and breaded pork frying, while roasting caused the loss of about 55%. Similar losses were found for loins processed 24 h and 7 days after slaughter. No SPM content was detectable in broth and grease produced during the processing.     

Concentration of biologically active polyamines in meat and liver of sheep and lambs after slaughter and their changes in mutton during storage and cooking

Putrescine (PUT), spermidine (SPD) and spermine (SPM) concentrations using a UPLC method, in chilled mutton, lamb and livers 24 h after slaughter were determined. PUT concentrations were quantifiable only in some samples. Mean SPD concentrations were 4–6, 13.5 and 16.8 mg kg⁻¹ in the meats, sheep and lamb livers, respectively. The respective SPM concentrations were 17–25, 128 and 79 mg kg⁻¹. SPD and SPM losses of about one fifth and half of the initial level, respectively, were apparent in mutton loins stored at −18 °C for 6 months. Significant losses of SPD and SPM were found in mutton loins stored aerobically, vacuum-packaged or in a modified atmosphere at + 2 °C. Boiling and stewing of mutton legs caused SPD and SPM losses of about 40% and roasting of about 60% of the initial content.     

Changes in the content of biologically active polyamines during beef loin storage and cooking

Dietary polyamines putrescine (PUT), spermidine (SPD) and spermine (SPM) participate in numerous human physiological processes, including tumour growth. Reliable information on their contents in foods is thus needed. Data for processed beef are very limited. Nine experiments with beef loin (longissimus lumborum) were, therefore, carried out. Loin cuts were stored at −18 °C for 178 days or beef was stored aerobically, vacuum-packaged (VP) and packaged in a modified atmosphere (MA; 70% N₂ and 30% CO₂, v/v) at +2 °C for 9, 21 and 21 days, respectively. The effects of three usual cooking treatments were also tested. Polyamines were determined after extraction with perchloric acid as dansyl derivatives using an HPLC method. Only SPM was detected at initial levels of 23.5–27.5 mg kg⁻¹, PUT and SPD contents were below the detection limits of 1.2 and 1.7 mg kg⁻¹, respectively. SPM content increased during the initial weeks of frozen storage and then gradually decreased to about 70% of the initial values at the end of the storage period (P < 0.05). No apparent SPM decrease was observed during aerobic storage for 9 days, while in VP and MA variants the losses were about 20% of the initial values on day 21 (P < 0.05). Slightly higher mean SPM losses were observed during boiling and stewing with and without added water. The differences among the cooking treatments were not significant. However, significant differences were observed among the loins used.     

Macronutrients content of Yellow Glacier Lily and Balsamroot; root vegetables used by indigenous peoples of northwestern North America

The macronutrients in two foods used by indigenous peoples of the British Columbia Plateau region were examined. Yellow Glacier Lily and Balsamroot were commonly harvested, processed and stored in large quantities, up until the last three decades, together with many other plant foods. The macronutrients of the two foods, in which the underground bulbs or roots are utilized, are mainly derived from the carbohydrates. Yellow Glacier Lily bulbs have a high starch content, (770 g kg⁻¹ in fresh bulbs, dry basis), and 57 g kg⁻¹ total dietary fibre. They also contain measurable amounts of simple sugars and fructans before and after cooking. Balsamroot, whose taproots were eaten, is another plant indigenous to the region, but unlike Yellow Glacier Lily it contains negligible amounts of starch. The edible portion of Balsamroot has a high total dietary fibre content (250 g kg⁻¹, dry basis), and high fructan content which is reduced to lower molecular weight sugars after pitcooking. The energy derived from the two foods is very similar on a dry basis ranging from 364 to 395 kcal 100 g⁻¹ in the fresh and pitcooked samples.     

Formation of biogenic amines during the maturity process of raw meat products, for example of cervelat sausage

The raw meat product cervelat sausage with a diameter of 90 mm was investigated during maturation and storage over a period of about 12 weeks. The examination was carried out by ion exchange chromatography (amino acid analyzer) and included the amines ethylamine, propylamine, butylamine, putrescine, histamine, cadaverine, tyramine, β-phenylethylamine, spermidine and spermine. In addition, the starter bacteria cultures varied according to manufacturer. Over the duration of investigation, five different production batches were observed in parallel. During the maturity process and storage, after 87 days, tyramine (58.9 mg kg⁻¹) showed a clear dominance, followed by spermine (34.1 mg kg⁻¹), putrescine (26.1 mg kg⁻¹) and spermidine (8.7 mg kg⁻¹), if starter bacteria culture 1 was used. Other amines were not detected. The use of starter bacteria culture 2 led, after 87 days, to the highest content of putrescine (244.1 mg kg⁻¹), followed by tyramine (119.2 mg kg⁻¹), histamine (52.9 mg kg⁻¹), spermine (37.5 mg kg⁻¹) and spermidine (9.2 mg kg⁻¹). With the use of starter bacteria culture 3, for spermine and spermidine a comparable behavior was shown to that with culture 1 or 2. After 87 days, putrescine reached the highest value of 484.2 mg kg⁻¹, followed by tyramine (119.4 mg kg⁻¹) and histamine (111.0 mg kg⁻¹). Cadaverine (36.9 mg kg⁻¹) could also be determined. As an accompanying investigation, the parameters pH, water activity (a_w) and microbial count (lactobacilli, enterobacteria, staphylococci and yeast) were determined. An investigation of the sections center-middle-edge showed that the content of amines increases to its highest values in the middle. The edge showed the lowest content. This behavior correlates with the a_w distribution of a raw sausage.     

A comparison of the toxicity of pirimiphos-methyl and malathion to Typhaea stercorea (L.) when applied to stored maize

The toxicity of freshly applied and aged residues of pirimiphos-methyl and malathion were assessed against adult Typhaea stercorea (L.). Maize was treated with each pesticide at doses of 2, 4, 6, and 8 mg kg⁻¹ and stored at a constant 25 °C and 70% r.h. for 12 weeks. All fresh deposits of pirimiphos-methyl produced 100% mortality as did malathion at 4, 6 and 8 mg kg⁻¹. After four weeks storage pirimiphos-methyl still gave 100% mortality at 6 and 8 mg kg⁻¹ but this dropped to 96% at 4 mg kg⁻¹ and 60% at 2 mg kg⁻¹, while mortality for malathion was less than 31% even at 8 mg kg⁻¹. After 12 weeks storage only pirimiphos-methyl gave effective control with 78% mortality at the highest dose of 8 mg kg⁻¹, while control by malathion had completely broken down. The effect of exposure time on T. stercorea for both pesticides at a single dose of 4 mg kg⁻¹ was also assessed. Beetles were left in contact with treated maize for 2, 4, 6, 8 and 10 d. Fresh and four-week-old pirimiphos-methyl residues produced over 98% mortality at all exposure periods but on 12-week-old residues mortality had dropped and was only 61% following 10 d exposure. Only freshly applied malathion gave 100% mortality and even the maximum exposure of 10 d only produced 51% mortality of T. stercorea at four weeks and 39% at 12 weeks.     

Concentration of biologically active polyamines in rabbit meat, liver and kidney after slaughter and their changes during meat storage and cooking

The concentration of putrescine (PUT), spermidine (SPD) and spermine (SPM) was determined in chilled meat and kidneys of 18 rabbits and in liver of 12 animals 24 h after slaughter. Very low PUT concentrations were detected only in kidneys. Mean SPD levels were 2.2, 2.2, 61.7 and 32.7 mg kg^− 1 in saddle, leg, liver and kidneys, respectively. The respective SPM concentrations were 14.7, 8.0, 115 and 88.4 mg kg^− 1. SPD and SPM losses of about one third of the initial levels were apparent in saddles stored at − 18 °C for 8 months. Losses of both polyamines of about 15-20% of the initial concentrations were found in saddles stored aerobically at + 2 °C for up to 9 days. Stewing of saddles caused significant SPD and SPM losses of about 20-25%, while upon roasting and pan-roasting without oil a decrease of about 50% of the initial concentration was observed.