黑龙江省大豆油脂脂肪酸组成的变迁

探讨了黑龙江省大豆油脂脂肪酸在９年间的组成上变化。研究结果表明，黑龙江省大豆油脂中的饱和脂肪酸下降，不饱和脂肪酸提高。亚油酸相对稳定，亚麻酸含量幅度被拓赛。试验结果还指出了品种的改良在油脂工业中的重要作用。     

一起由食用家庭自制辣椒酱引起肉毒中毒的实验室诊断

目的 对1例疑似肉毒中毒病例的相关样品进行实验室检测。方法 参照GB 4789.12—2016对病例暴露食品样品（自制辣椒酱、咸菜、芝麻酱、卤猪蹄）和粪便标本进行前处理,应用实时荧光定量聚合酶链式反应（PCR）检测样品/标本中肉毒毒素基因,通过动物试验进行毒素检测和型别确认,经接种疱肉培养基和TPGYT培养基增菌培养,采用血琼脂平板进行分离、纯化,并做菌种鉴定。结果 5份样品/标本经实时荧光定量PCR法检测,仅在自制辣椒酱样品中检测到A型肉毒毒素基因;通过动物试验进行毒素检测,在自制辣椒酱样品中检测到A型肉毒毒素,其他样品/标本中未检测到肉毒毒素;5份样品/标本中,从自制辣椒酱和卤猪蹄样品中均分离到A型肉毒梭菌。结论 该起中毒事件是由食用肉毒梭菌污染的家庭自制辣椒酱引起。     

Nachweis von Clostridium botulinum Typ A, B, E und F mittels real-time-PCR

Clostridium botulinum is a Gram-positive, anaerobic, spore-performing bacterium with the ability to produce under certain conditions a protein with a characteristical neurotoxicity. Intoxications with C. botulinum toxin belong to the rare occuring food-poisonings; the mortality, however, is very high. C. botulinum produce seven different toxin types (type A to G), human intoxications are currently described to caused by toxin type A, B, E and F. C. botulinum is a strictly anaerobic growing bacterium, so the risk for the consumer’s health is mainly due to non-commercially produced food cans. A special form of botulism is the „infant botulism“. In contrast to the botulism of adults, where the disease is caused through toxin-containing food, spores of C. botulinum can sporulate and produce toxin in the intestines of an infant. The source of infant botulism can be honey, because it contains as a natural product C. botulinum spores. Because of the difficult and time-consuming cultural detection of C. botulinum, PCR methods to screen for the toxin genes A, B, E and F, which are relevant in the human medicine, have been used increasingly during the last years. In this presentation two real-time-PCR assays for C. botulinum, which can be applied in the routine laboratory, will be shown.

---

Zusammenfassung: Clostridium botulinum z?hlt zu den anaeroben sporenbildenden Bakterien, die unter bestimmten Bedingungen in der Lage sind, sich in Lebensmitteln zu vermehren und ein Protein mit charakteristischer Neurotoxizit?t zu bilden. Intoxikationen mit Clostridium botulinum-Toxin geh?ren zu den seltenen lebensmittelassoziierten Intoxikationen; die Mortalit?t bei einer Erkrankung ist allerdings sehr hoch. C. botulinum produziert sieben unterschiedliche Toxintypen (Typ A-G), wobei für menschliche Erkrankungsf?lle bisher die Toxintypen A, B, E und F beschrieben sind. Da es sich bei den genannten Keimen um strikt anaerob wachsende Bakterien handelt, stellen vor allem nicht kommerziell hergestellte Konserven, wie z. B. Kesselkonserven, ein Risiko für den Verbraucher dar. Als besondere Form des Botulismus wird der so genannte „S?uglingsbotulismus“ beschrieben. Im Gegensatz zur der Erkrankung, die bei Erwachsenen auftritt und die durch die Aufnahme des bereits toxinhaltigen Lebensmittels verursacht wird, k?nnen Sporen von C. botulinum im Darm von S?uglingen auskeimen und dort Toxine bilden. Ursache für den S?uglingsbotulismus ist h?ufig Honig, der als Naturprodukt C. botulinum-Sporen enthalten kann. Da der kulturelle Nachweis von C. botulinum aufwendig und eine endgültige Differenzierung schwierig ist, wird im Bereich der Routinediagnostik seit einigen Jahren verst?rkt mit PCR-Nachweisverfahren gearbeitet, die ein schnelles Screening auf das Vorhandensein der vier in der Humanmedizin relevanten Toxingene A, B, E und F erm?glichen. In dieser Arbeit werden zwei real-time-PCR-Systeme vorgestellt, die im Bereich der Routinediagnostik einsetzbar sind.

---

Eingegangen: 19. Januar 2007     

Antilisterial effects of free fatty acids and monolaurin in beef emulsions and hot dogs

This study was undertaken to screen fatty acids, conjugated isomers of linoleic acid (CLA), and monolaurin for antilisterial effects in broth, and to further test the active compounds in cooked comminuted beef and hot dogs. Capric, lauric, myristic, palmitic, stearic, oleic, linoleic, and linolenic acid, CLA and monolaurin were screened in sterile nutrient broth at concentrations of 5 to 700 μg/ml. The media were inoculated with 10³ cfu/ml of L. monocytogenes strain Scott A and incubated at 32°C for up to 8 days. Cell enumeration data showed that lauric acid was most inhibitory, followed by monolaurin, and capric acid. Tests in comminuted sterile beef stored at 5°C for 21 days showed log cfu/g of: 8.5 (control), 7.3 (500 μg/g lauric acid), and 4.7 (500 lauric acid+300 capric acid). Similar results were observed in beef hot dog emulsion to which lauricidin, lauric acid, capric acid, and the acid combination were added prior to heat treatment. At 500 μg/g, monolaurin and lauric acid caused similar delayed growth effects at 5°C, whereas the combination of the two acids showed enhanced inhibition on prolonged storage. Nonetheless, the observed 5-log increase in numbers of L. monocytogenes during 45 days of storage indicates limited control of the pathogen in refrigerated cooked meat products.     

Changes in texture, colour and fatty acid composition of male and female pig shoulder fat due to different dietary fat sources

Two experiments with 72 slaughter pigs in each were conducted. Entire males and females were individually fed restricted. Palm kernel-, soybean- and fish-oil were used in varying combinations, giving different dietary fat levels (29-80 g/kg) and iodine values ranging from 50 to 131. Shoulder fat was analysed for fatty acid composition (inner and outer layer), firmness and colour. A clear dose-response relationship was seen between fatty acids in diets and in shoulder fat. Interestingly, the very long chain n-3 fatty acids seemed to be deposited more efficiently when additional fat was included in the diet. Both high and low dietary iodine values changed towards less extreme iodine values in fat. Low-fat diets enhanced de novo synthesis of fatty acids. Males revealed a higher percentage of PUFA and a lower percentage of C18:1 and MUFA. Fat firmness, but not colour, was influenced by sex and dietary fat source.     

某企业婴儿肉毒中毒乳粉相关样品中肉毒梭菌的分离与分型

目的 对从某企业获取的30批次婴儿配方乳粉样品进行肉毒毒素和肉毒梭菌检测，对分离到的1株B型肉毒梭菌进行全基因组测序分析。方法 参照GB 4789.12—2016《食品安全国家标准 食品微生物学检验 肉毒梭菌及肉毒毒素检验》对样品进行肉毒梭菌分离及肉毒毒素分型实验；对分离到的菌株进行全基因组测序，并分析菌株的遗传特征。结果 30批次样品中均未检出肉毒毒素；将增菌液进行小鼠腹腔注射后，4批次乳粉样品出现了典型小鼠肉毒中毒症状，但仅从1批次乳粉样品中分离到肉毒梭菌。基因组测序分析显示，该菌为Ⅰ群B型肉毒梭菌，毒素基因簇为Ha型，毒素基因为B2亚型。结论 针对背景微生物复杂的婴儿配方乳粉中肉毒梭菌检测，不应以菌种分离作为金标准，而应以增菌液小鼠毒性实验结合肉毒抗血清保护实验作为确认方法。全基因组测序可对分离菌种进行精准鉴定和相关遗传特征分析，为中毒事件处理提供可靠的技术支撑。     

Amino acids,fatty acids and sterols profile of some marine organisms from Portuguese waters

Marine organisms have been increasingly regarded as good sources of new drugs for human therapeutics and also as nutrients for human diet. The amino acids, fatty acids and sterols profiles of the widely consumed echinoderms Paracentrotus lividus Lamarck (sea urchin), Holothuria forskali Chiaje (sea cucumber), the gastropod molluscs Aplysia fasciata Poiret and Aplysia punctata Cuvier (sea hares), from Portuguese waters, were established by GC–MS analysis. Overall, 10 amino acids, 14 fatty acids and 4 sterols were determined. In general, all species presented the 10 amino acids identified, with the exceptions of H. forskali, in which no glycine, proline, trans-4-hydroxy-proline or phenylalanine were found, and of A. fasciata which did not contain proline. Unsaturated fatty acids were predominant compounds, with those from the ω-6 series, being in higher amounts than their ω-3 homologues, and cholesterol being the main sterol. The amino acids, fatty acids and sterols qualitative and quantitative composition of A. fasciata, A. punctata and H. forskali is reported here for the first time.     

The composition of fatty acids in the tissues of Tunisian swordfish (Xiphias gladius)

The objective of this study was to compare the composition of fatty acids stored in the various parts of swordfish. Muscle and organ sections of a series of swordfish samples were collected. Their chemical analysis allowed the classification of swordfish as a semi-fatty fish, with its byproducts totalling 35.6% of the total fatty acids (TFA) and its white and red muscles (MR) 7.2%. The highest contents were found in the liver (26%), the gonads (4.7%) and the red muscle (RM) (4.5%). The UFA/SFA ratio as recommended by nutritionists is 3; in the liver, skin and RM samples this ratio was, respectively, 3.5, 2.8 and 2.7. There is a high level of unsaturated fatty acids (UFA) in swordfish. More than 40% of the muscular tissues are made up of polyunsaturated fatty acids (PUFA) of the n-3 series (EPA + DHA). The byproducts contain more than 30% of monounsaturated acids characterised by the fatty acids of the n-9 series and particularly by oleic acid.     

Changes in membrane fatty acids and murein composition of Bacillus cereus and Salmonella Typhi induced by gamma irradiation treatment

This present study was carried out to evaluate the effects of gamma irradiation on the fatty acids (FA) and mureins composition of two different radiotolerant bacteria. Bacillus cereus LSPQ 2872 and Salmonella Typhi ATCC 19430 were used for this study. The bacterial strains were treated with a sublethal radiation dose of 1 kGy to cause a cellular damage. Gas chromatography (GC) and high performance liquid chromatography (HPLC) analysis were performed to demonstrate respectively the modification of the FA composition and the changes in muropeptide profile. Results obtained show, for both bacteria, that this treatment had a significant effect (P ≤ 0.05) on the FA content with an increase of unsaturated FA percentage. Substantial changes were also noticed for the relative percentage and the number of the muropeptides. This study represents one of the few to demonstrate the modifications on bacterial membrane as a cellular response to survive the ionising radiation stress.     

Changes in sugars, acids and fatty acids in naturally parthenocarpic date plum persimmon (Diospyros lotus L.) fruit during maturation and ripening

The date plum persimmon fruit (Diospyros lotus L., fam: Ebenaceae) is cultivated throughout northern of Turkey for its edible fruits. Sugars and organic acids were measured during fruit maturation and ripening using HPLC. The analyses showed that fructose and glucose were the main sugars accumulated in the fruit pulp. Fructose and glucose increased up to 43,552.8 mg.100 g^–1 fw and 35,450.8 mg.100 g^–1 fw respectively during fruit ripening. Sucrose content remained relatively low and decreased during ripening. The major organic acids found in date plum fruit were citric and malic acids, which increased through the immature and midripe maturity, and then the levels decreased in the overripe fruit. Palmitic acid (16:0), palmitoleic acid (16:1), stearic acid (18:0), oleic acid (18:1) and linolenic acid (18:3) were among the major fatty acids determined by GC throughout the maturation and ripening of the fruits. The levels of these fatty acids were found to be significantly different (P=0.05) between the three maturity stages. The fruits displayed the level of linoleic acid (0.7%) in low and -linolenic acid (17.8%) in higher quantities, and the combined levels of linoleic and -linolenic acid comprised 19% (120.1 g.g^–1 dw) of the total fatty acid content in the over ripened fruit. These results show that naturally parthenocarpic date plum fruits have high levels of sugars and organic acids and moderate levels of fatty acids that significantly changed during maturation and ripening. This information can be used by nutritionalists and food technologists to improve the nutrition of local people and develop food products that would be beneficial to human health.     

Flavouring of imitation cheese with enzyme-modified cheeses (EMCs): Sensory impact and measurement of aroma active short chain fatty acids (SCFAs)

Enzyme-modified cheeses (EMCs) are used to impart flavour to imitation cheese products. Cheeses (pH 6 or 5.5) were formulated with 5% w/w EMC, having low, medium or high levels of lipolysis and were examined by a sensory panel. Free fatty acid analyses were performed using SPME/GC. The flavour profile of the flavoured cheeses was affected by EMC composition and pH of the cheese base. Cheeses at a pH of 6.0, flavoured with low lipolysis EMCs, were described as ‘bland’. Lowering the pH of the cheese matrix to 5.5 appeared to increase the flavour intensity of the cheese flavoured with low lipolysis EMC and panellists ranked this cheese the highest, describing its flavour as ‘well-balanced and ‘cheesy’. This study shows that the flavours of imitation cheeses are influenced by the level of lipolysis of the EMCs used to flavour them and also by the pH of the cheese base.     

Seasonal changes in the fatty acids of gilthead sea bream (<Emphasis Type="Italic">Sparus aurata</Emphasis>) and white sea bream (<Emphasis Type="Italic">Diplodus sargus</Emphasis>) captured in Iskenderun Bay,eastern Mediterranean coast of Turkey

Seasonal variations in the fatty acid compositions of gilthead sea bream (Sparus aurata) and white sea bream (Diplodus sargus), captured in Iskenderun Bay, Eastern Mediterranean of Turkey, were investigated. Results from studying the composition over all seasons showed that the basic saturated, monounsaturated and polyunsaturated fatty acids for gilthead sea bream and white sea bream were palmitic acid (16:0), oleic acid (18:1) and docosahexaenoic acid (DHA, 22:63). The other main fatty acids for both species were myristic acid (14:0), stearic acid (18:0), palmitoleic acid (16:1), linoleic acid (18:26) (especially in autumn and winter for gilthead sea bream), and eicosapentaenoic acid (EPA, 20:53). Gilthead sea bream and white sea bream exhibited seasonal fluctuations in their fatty acid contents. EPA ratios in gilthead sea bream in the autumn, winter, spring and summer were 5.42%, 4.69%, 5.20% and 4.27%, whereas the ratios in white sea bream in autumn, spring and summer were found to be 5.03%, 4.53% and 6.97%, respectively. DHA ratios in gilthead sea bream in autumn, winter, spring and summer were 15.37%, 14.16%, 9.51% and 7.07%, whereas the ratios in white sea bream in autumn, spring and summer were found to be 11.49%, 20.17% and 7.74%, respectively. The present study suggests that the daily consumption of either 100 g of gilthead sea bream captured in any season or 100 g white sea bream captured in spring or summer could meet peoples needs for EPA+DHA fatty acids.     

Effects on growth performance, carcass characteristics, and the fat and meat fatty acid profile of rabbits fed diets with chia (Salvia hispanica L.) seed supplements

The effects of three levels (0%, 10%, or 15%) of chia (Salvia hispanica L.) seed (SHS) included in the diet on the growth performance, some carcass characteristics and fatty acid profile of rabbit meat and perirenal fat was studied. At the end of the experiment, there were no significant differences among the groups in live weight, live weight gain, feed consumption, feed efficiency, carcass yield or the percentages of edible organs. The percentage values of hind legs, fore legs, loin and abdominal wall, breast and ribs, skin and limbs, and head were not affected by the inclusion level of SHS. The polyunsaturated fatty acid (PUFA) concentration in the longissimus dorsi muscle and perirenal fat was significantly increased with increasing SHS inclusion, while the saturated fatty acid (SFA) decreased. The n − 6/n − 3 PUFA ratio of the rabbit meat decreased from 4.55 in the control group, to 1.03 in the 15% SHS group.     

Fat and fatty acids of white lupin (Lupinus albus L.) in comparison to sesame (Sesamum indicum L.)

The study was undertaken to compare fat and fatty acid profiles in white lupin (Lupinus albus ssp. albus) and sesame (Sesamum indicum L.), representing two different families, Fabaceae and Pedaliaceae. Fat levels were 10.74% and 55.44% in seeds of white lupin and sesame, respectively. The results indicated that oleic, linolenic and arachidic acids in seed fat were higher in white lupin than in sesame cultivars. Oleic acid was the predominant fatty acid in white lupin, whereas linoleic acid was predominant in sesame. Fat content (%) was statistically significantly correlated with linoleic, linolenic and arachidic acids at the genotypic level. The fatty acid composition of white lupin is useful for human consumption. Although oil content of white lupin was lower than that of sesame, white sweet lupin could be improved.     

1959—2022年青海省食源性肉毒中毒事件流行病学分析

目的 分析青海省食源性肉毒中毒事件流行特征及影响因素,为防控提供科学依据。方法 收集1959—2022年青海省肉毒中毒数据,应用Excel 2021进行流行病学特征分析,利用R 4.2.3对事件数和病死率进行Mann-Kendall趋势检验,运用ArcGis 10.2软件制作空间分布图。结果 1959—2022年发生食源性肉毒中毒事件86起,发病348人,死亡195人,病死率为56.03%。中毒主要发生在第二、三季度,牧民为主要的发病人群,肉毒毒素型别主要为E型,“风干肉”为主要的中毒食品,生食和开锅即食为主要的食用方式。结论 青海省食源性肉毒中毒病死率整体呈下降趋势,发病地区也逐渐缩小,但作为我国高发地区之一,病死率仍处于较高水平,应进一步加强对高危人群食品安全教育,提高基层医疗机构对肉毒中毒的救治能力,减少中毒事件的发生和死亡。     

Effect of intensive vs. free range production on the fat and fatty acid composition of whole birds and edible portions of retail chickens in the UK

The primary objective was to compare the fat and fatty acid contents of cooked retail chickens from intensive and free range systems. Total fat comprised approximately 14, 2.5, 8, 9 and 15 g/100 g cooked weight in whole birds, skinless breast, breast with skin, skinless leg and leg meat with skin, respectively, with no effect of intensive compared with free range systems. Free range breast and leg meat contained significantly less polyunsaturated fatty acids (n-6 and n-3) than did those from intensive rearing and had a consistently higher n-6/n-3 ratio (6.0 vs. 7.9). Generally, the concentrations of long chain n-3 fatty acids were considerably lower than those reported in earlier research studies. Overall, there was no evidence that meat from free range chickens had a fatty acid profile that would be classified as healthier than that from intensively reared birds and indeed, in some aspects, the opposite was the case.     

澳洲金鲈鱼种肌肉中氨基酸与脂肪酸组成的分析

目的研究澳洲金鲈肌肉中营养成分组成。方法采用色谱法和常规分析化学法检测出澳洲金鲈鱼种肌肉中蛋白质、脂肪、氨基酸和脂肪酸等含量,并对肌肉中氨基酸与脂肪酸组成进行分析和评价。结果澳洲金鲈鱼种肌肉中含有17种氨基酸(未测色氨酸),在必需氨基酸中含量最高的是赖氨酸,含量最低的是蛋氨酸,必需氨基酸占氨基酸总量的39.67%;第一限制性氨基酸是蛋氨酸和胱氨酸;氨基酸比值系数分为78.55%;必需氨基酸指数为89.64%;澳洲金鲈的蛋白质营养符合E/T应为40%左右和E/NT应为60%以上的参考蛋白质模式标准。澳洲金鲈含有22种脂肪酸,含量最高的是油酸,亚油酸次之;不饱和脂肪总量为64.4%。结论澳洲金鲈具有营养价值高、味道鲜美等特点,可以作为我国优良品种引进及产业化开发的淡水鱼。     

Variability of the lipolytic activity in Yarrowia lipolytica strains in pork fat

This work studied the variability in lipolytic activity in 35 strains of Yarrowia lipolytica inoculated in pork fat after 7 and 21 days of storage at 15 °C. The strains were able to generate three different hydrolysis profiles. In particular, the strains PO10, PO14, RO1, RO5, Y15, Y16A, Y20, B5, 7B, 7B3, 16B and 21C caused an increase with time in concentrations of C16:0, C18:0, C18:1, C18:1(Δ11) and C18:2 which were the predominant free fatty acids (FFAs). On the contrary, the strains PO1, PO19, PO23, RO22, Y12, B4, B74, GB, 5B, 5D, 27D and W29 showed an opposite trend, while the remaining ones induced no change. Because the released FFAs can be considered precursors for flavour development, the results suggest the potential use of some Y. lipolytica strains in sausage making to improve the overall aroma.     

The effect of production system and age on concentrations of fatty acids in intramuscular fat of the longissimus and triceps brachii muscles of Angus-cross heifers

The concentrations of fatty acids were measured in intramuscular fat from the longissimus lumborum (LL) and triceps brachii (TB) muscles of Angus-cross heifers finished either on a high-concentrate ration in Washington, USA, (US cattle, n = 15) or on pasture in New Zealand (NZ cattle, n = 16). Half of the NZ cattle were of a similar age to the US cattle (NZAge) and half were of a similar weight (NZWt). Intramuscular fat levels were higher for the LL muscle and for the US cattle but only within the LL muscle (P < 0.05). Aspects of the fatty-acid patterns that are of relevance to human nutrition tended to favour the pasture-finished NZ cattle with lower n − 6/n − 3 fatty acid ratios (P < 0.001), higher concentrations of an anticarcinogenic conjugated linoleic acid (C18:2 c9,t11) (P < 0.05) and its precursor (trans-vaccenic acid, TVA) (P < 0.01), and lower levels of the 18-carbon trans monounsaturated fatty acids other than TVA (P < 0.01). Concentrations of 20 of the 22 fatty acids analysed differed significantly between the two muscles. When values were adjusted to a common intramuscular fat level by covariance, most of the group differences remained, but a number of the muscle differences became non-significant. For almost half the fatty acids considered, there was a significant interaction between treatment group and muscle, which indicates that the results for one muscle do not necessarily apply to other muscles, although the ranking of the groups was usually the same for both muscles.