云南野生食用菌边角料主要营养成分研究

目的为野生食用菌高值化利用与开发提供科学依据。方法以松茸、鸡枞、黄牛肝菌、白牛肝菌、青头菌5种云南野生食用菌边角料为材料,采用国家标准方法测定其主要营养成分。结果水分、灰分、粗蛋白、粗脂肪、粗纤维、总糖、水溶性化合物、总碳水化合物、全氨基酸和常见金属元素的含量在5种野生食用菌中存在极显著差异(P0.01)。其中,白牛肝菌的水分含量、粗蛋白含量、粗脂肪含量、粗纤维含量、水溶性成分含量和全氨基酸含量均最高(分别为88.73%、35.66%、1.76%、8.23%、40.49%、20.78%),黄牛肝菌的灰分含量最高(6.03%),松茸的总糖和总碳水化合物含量最高(分别为35.07%、58.40%)。白牛肝菌的钙、铜含量最高(分别为97.79 mg/100 g、3.13 mg/100g),鸡枞的铁、镁含量最高(分别为107.26 mg/100 g、115.37 mg/100g),松茸的锌、锰含量最高(分别为56.40 mg/100 g、5.08 mg/100 g)。结论 5种野生食用菌边角料均含有人体所需的氨基酸,主要营养成分含量存在极显著差异,属于高蛋白低脂肪,鲜嫩可口的健康食材。     

7种云南野生食用菌的氨基酸组成比较分析及 营养评价

目的对产自云南本地的7种野生食用菌中的17种氨基酸进行含量测定和营养评价。方法采用酸水解法处理样品后,利用氨基酸自动分析仪测定样品中的氨基酸含量。计算7种野生菌中必需氨基酸占总氨基酸的质量分数、氨基酸比值、氨基酸比值系数和比值系数分,并根据世界卫生组织/联合国粮农组织(WHO/FAO)颁布的理想蛋白质必需氨基酸模式谱对7种野生食用菌中的氨基酸进行营养评价。结果 7种野生食用菌中氨基酸配比最为合理的是鸡枞和干巴菌,接近理想蛋白质的要求;虽然羊肚菌的各类氨基酸含量均高于其他6种野生菌,但其必需氨基酸所占比例较低;除羊肚菌外,其他6种野生菌的鲜味氨基酸含量均高于20%,其中块菌的鲜味氨基酸含量最高,达28.65%;亮氨酸和异亮氨酸在7种野生食用菌中均相对不足,并且亮氨酸是其中5种野生菌的第一限制氨基酸;甲硫氨酸在除黑鸡枞以外的其他野生菌中均相对过剩;鸡枞的氨基酸比值系数分为85.9,氨基酸营养价值最高,羊肚菌的比值系数分仅为15.15;7种野生食用菌中赖氨酸的平均含量是WHO/FAO模式谱的1.40倍。结论各类野生食用菌中的氨基酸含量差异较大,有必要对更多种类、不同产地的食用菌的氨基酸配比开展深入研究。     

彩云之南的蘑菇派对

云南气候温和湿润，草茂林深，盛产珍稀的野生食用菌、据说世界上可供食用的菌类共有600多种，而云南就拥有300多种，其中像牛肝菌、猴头菇、干巴菌、鸡枞、松茸这样的特产野生菌不但味道鲜美，还含有极为丰富的营养成分，是备受推崇的保健食品。     

黑皮鸡枞菌营养与质构特性分析及其抗氧化活性评价

以人工种植黑皮鸡枞菌为原料,分别对其和平菇、海鲜菇、白玉菇、香菇和金针菇的营养成分、色泽、抗氧化活性、质构特性进行分析和评价。结果表明:在设定25、50、75、100℃四个预煮温度下,黑皮鸡枞菌的相关物理特性与其它五种食用菌相比,硬度、弹性及咀嚼性更好。分析发现黑皮鸡枞菌子实体包含17种氨基酸,必需氨基酸占总氨基酸的33.98%,菌盖中的总氨基酸含量是菌柄的1.27倍。黑皮鸡枞菌中甜味氨基酸（甘氨酸和丙氨酸）和鲜味氨基酸（天冬氨酸和谷氨酸）含量相对较高,其中鲜味氨基酸总量为12045.97 mg/100 g,占氨基酸总含量百分比为76.73%,是海鲜菇的1.01倍,阐明了黑皮鸡枞菌食用时口味鲜美的原因。黑皮鸡枞菌乙醇提取物中总酚含量4.86 mg/g（鲜重）;在选定的6种食用菌中,黑皮鸡枞菌的抗氧化能力最高,其DPPH·、ABTS+·和·OH清除能力的IC₅₀值分别为0.656、0.234、0.654 mL/mL。综合而言,人工黑皮鸡枞菌作为一种食用菌,具有良好的食用口感和较高的营养价值。     

菌菇:藏在云南深山的野生菌

正每年夏日雨季正是云南野生菌的生长旺季,鸡枞菌、牛肝菌、松茸、干巴菌纷纷破土而出。云南得天独厚的气候条件,复杂的地形地貌,孕育了多种森林类型、多样土壤类型和丰富的物种,成为生物多样性的宝库,也成为了种类繁多食用菌的家园。更是有所谓的"四大名菌",其实并没有官方的定义,当地比较通行的说法是:松茸、羊肚、鸡枞、黑虎掌。     

云南三种特色野生食用菌营养成分分析与评价

以云南当地三种特色珍稀野生食用菌红蜡蘑、红顶枝瑚菌和昆明乳牛肝菌为原料,采用国家标准方法,测定其各种营养成分(总糖、粗纤维、蛋白质、脂肪、矿物质、氨基酸和维生素等)的含量,并进行综合评价。结果表明:三种野生食用菌均为高蛋白、高纤维、低脂肪,富含人体所需矿物质元素和维生素,营养价值很高的食用菌。三种特色野生食用菌所含氨基酸种类丰富且含量高,均含有17种氨基酸,其中必需氨基酸7种,非必需氨基酸10种,氨基酸中均以呈鲜味的谷氨酸含量最高。其中,必需氨基酸在总氨基酸中所占的比例在37.31%~40.62%之间,必需氨基酸/非必需氨基酸比值(E/N)达0.60~0.68。通过对三种野生食用菌营养成分的分析,发现红蜡蘑中的各营养成分稍高于红顶枝瑚菌和昆明乳牛肝菌,这为进一步开发利用特色野生食用菌资源提供理论依据。     

松茸菌汤熬制工艺参数优化及风味成分分析

以云南产新鲜松茸菌为主要原料,研究松茸菌汤熬制的主要工艺参数。以菌汤中固形物溶出率和蛋白质溶出率为考察指标,通过单因素试验和正交试验分析和讨论,确定松茸菌汤熬制工艺参数,并对松茸菌汤中的氨基酸、呈味核苷酸和风味成分进行分析。结果表明：松茸菌汤熬制的最佳工艺为料液比1∶60（g/mL）、熬制时间90 min、熬制火力中火（1 000 W）,此时菌汤中固形物溶出率为49.68%,蛋白质溶出率为45.74%;菌汤中总氨基酸和游离氨基酸均为17 种,含量分别为109.60 mg/100 mL和41.20 mg/100 mL;呈味核苷酸5’-肌苷酸二钠和5’-鸟苷酸二钠含量分别为2.0 μg/mL和28.4 μg/mL;气相色谱-质谱联用测得菌汤中挥发性物质共28 种,其中醇类物质所占比例最大。     

云南产6种野生食用牛肝菌的营养成分及抗氧化特性研究

本文研究了云南产6种野生食用牛肝菌的氨基酸组成及氨基酸评分、多酚提取物及其抗氧化活性、多糖制取物及其抗氧化活性。结果表明,6种牛肝菌中17种氨基酸种类齐全,含量丰富,氨基酸总量为23.13%DW(B.bicolor)~30.69%DW(B.speciosus),品种间差异显著(p0.05);疏水性氨基酸所占比例较高;天冬氨酸、谷氨酸、甘氨酸、丙氨酸和半胱氨酸是含量最高的氨基酸种类;以总氨基酸为基础,6种牛肝菌氨基酸评分较高,为0.59(B.speciosus)~0.94(B.bicolor)。6种牛肝菌中多酚含量丰富,为1.20 mg GAE/g DW(B.Sinicus)~10.32 mg GAE/g DW(B.speciosus);多酚提取物的抗氧化活性显著,特别是B.bicolor和B.craspedius表现出显著高于BHT的抑制脂质体过氧化的能力(p0.05)。6种牛肝菌水溶性粗多糖得率较高,为11.67%DW(B.craspedius)~20.00%DW(B.speciosus);粗多糖中的60%醇溶组分和40%醇溶组分在不同抗氧化体系中均表现出较好的抗氧化活性。表明6种野生食用牛肝菌的营养价值高,多酚及多糖等功能性成分含量高、抗氧化活性强,是潜在的抗氧化物资源。     

四川省鸡枞菌氨基酸组成及硒元素含量分析

采集获得四川省内10种鸡枞菌,利用全自动氨基酸分析仪测定其氨基酸组成及含量,利用原子荧光光度仪分析其硒元素含量,并利用统计学方法进行分析。结果表明：鸡枞菌子实体氨基酸含量高,总氨基酸为15.92%～28.86%,必需氨基酸含量分别为7.08%～10.20%,普通鸡枞、裂纹鸡枞、乌黑鸡枞、谷堆鸡枞、粗柄鸡枞及小鸡枞的氨基酸含量均超过20%,其中谷堆鸡枞总氨基酸及必需氨基酸分别达到28.86%、10.20%。鸡枞菌中硒含量亦较高,为长根菇的3～18倍,其中乌黑鸡枞含量达到(1.2286±0.0340)μg/g。可见四川省鸡枞菌氨基酸种类、硒含量丰富,营养价值高。     

云南剥隘鸡与河南肉鸡肌肉中肌苷酸含量的 比较研究

目的比较研究不同月龄、性别的云南剥隘鸡与河南肉鸡肌肉中不同胴体部位的肌苷酸含量。方法随机选取健康5月、7月龄左右的云南剥隘鸡、河南肉鸡,公母各10只,屠宰取胸肌和腿肌待测。采用高效液相色谱法测定出不同月龄(5、7月龄)、性别及胴体部位(胸肌、腿肌)的云南剥隘鸡和河南肉鸡肌肉中肌苷酸含量。结果云南剥隘鸡、河南肉鸡肌肉中肌苷酸含量分别为2.4374~3.3192 mg/g、2.2095~3.0220 mg/g;5月、7月龄的云南剥隘鸡肌肉中肌苷酸含量均显著高于同月龄的河南肉鸡(P0.05);云南剥隘鸡肌肉中肌苷酸含量高于同性别的河南肉鸡,其中2种品种的母鸡肌肉中肌苷酸含量差距更显著(P0.05);云南剥隘鸡胸肌、腿肌中肌苷酸含量均显著高于相同胴体部位的河南肉鸡(P0.05)。结论不同月龄、性别、胴体部位对2个品种鸡肌肉中肌苷酸含量的差异性均产生显著影响,云南剥隘鸡肌肉中肌苷酸含量要高于相同条件下的河南肉鸡。     

Determination of ethanol,volatile fatty acids,lactic and succinic acids in fermentation liquids by gas chromatography

A rapid and simple quantitative method was developed to determine, by gas chromatography, the concentrations in fermentation liquids of ethanol, the C₂-C₆ volatile fatty acids, and lactic and succinic acids. Aqueous samples were acidified with 250μlml^?1 metaphosphoric acid (5:1 ratio), centrifuged, and injected directly on to a column containing a porous aromatic polymer (Chromosorb 101) maintained at 200°C in a gas chromatograph fitted with a flame ionisation detector. It was unnecessary to purify samples further before injection, although distillation and ion-exchange methods were examined. Derivatisation of lactic and succinic acids before injection was not necessary, but the lowest level of detection of these two relatively non-volatile acids was about four times greater than that for the volatile fatty acids. The method described was suitable for the analysis of rumen fluid, methane digester fluid, silage extracts and other anaerobic fermentation fluids. The relative retention times are given for 23 organic acids and six other fermentation end-products.     

Effects of abomasal infusions of fatty acids and 1-carbon donors on apparent fatty acid digestibility and incorporation into milk fat in cows

Our primary objective was to determine the effects of the abomasal infusion of 16-carbon (16C) and 22-carbon (22C) fatty acids (FA) on apparent FA digestibility, plasma FA concentrations, and their incorporation into milk fat in cows. Our secondary objective was to study the effects of 1-carbon donors choline and l-serine on these variables. Five rumen-cannulated Holstein cows (214 ± 4.9 d in milk; 3.2 ± 1.1 parity) were enrolled in a 5 × 5 Latin square experiment with experimental periods lasting 6 d. Abomasal infusates consisted of (1) palmitic acid (PA; 98% 16:0 of total fat), (2) PA + choline chloride (PA+CC; 50 g/d of choline chloride), (3) PA + l-serine (PA+S; 170 g/d of l-serine), (4) behenic acid (BA; 92% 22:0 of total fat), and (5) docosahexaenoic acid algal oil (DHA; 47.5% DHA of total fat). Emulsions were formulated to provide 301 g/d of total FA and were balanced to provide a minimum of 40 and 19 g/d of 16:0 and glycerol, respectively, to match the content found in the infused algal oil. Apparent digestibility of FA was highest in DHA, intermediate in PA, and lowest in BA. Digestibility of 16C FA was lowest in BA and highest in PA. The digestibility of 22C FA was highest in DHA relative to BA (99 vs. 58%), whereas 1-carbon donors had no effect on 22C FA digestibility. Plasma 16C FA concentrations were greatest with PA treatment, and 22C FA concentrations were ~3-fold greater in DHA-treated cows relative to all other treatments. Milk fat 16:0 content was highest in PA relative to BA and DHA (e.g., 37 vs. 27% in PA and DHA), whereas the milk yield of 16:0 was higher in PA relative to DHA (i.e., 454 vs. 235 g/d). Similarly, milk 22:0 content and yield were ~10-fold higher in BA relative to all other treatments, whereas DHA treatment resulted in higher content and yield of 22:6 in milk fat relative to all other treatments (41- and 38-fold higher, respectively). Consequently, the content of FA >16C (i.e., preformed) was higher in milk fat from cows infused with BA and DHA relative to PA. De novo FA content in milk did not differ between PA, PA+CC, and PA+S (~16% of milk fat) but was higher in BA and DHA treatments (19 and 21%, respectively). We conclude that FA carbon chain length and degree of saturation affected FA digestibility and availability for absorption as well as their incorporation into milk fat. The abomasal infusion of choline chloride and l-serine did not modify these variables relative to infusing palmitic acid alone.     

Short communication: Eicosatrienoic acid and docosatrienoic acid do not promote vaccenic acid accumulation in mixed ruminal cultures

Previous research found that docosahexaenoic acid (C22:6n-3) was a component of fish oil that promotes trans-C18:1 accumulation in ruminal cultures when incubated with linoleic acid. The objective of this study was to determine if eicosatrienoic acid (C20:3n-3) and docosatrienoic acid (C22:3n-3), n-3 fatty acids in fish oil, promote accumulation of trans-C18:1, vaccenic acid (VA) in particular, using cultures of mixed ruminal microorganisms. Treatments consisted of control, control plus 5 mg of C20:3n-3 (ETA), control plus 5 mg of C22:3n-3 (DTA), control plus 15 mg of linoleic acid (LA), control plus 5 mg of C20:3n-3 and 15 mg of linoleic acid (ETALA), and control plus 5 mg of C22:3n-3 and 15 mg of linoleic acid (DTALA). Treatments were incubated in triplicate in 125-mL flasks, and 5 mL of culture contents was taken at 0 and 24 h for fatty acid analysis by gas-liquid chromatography. After 24 h of incubation, the concentrations of trans-C18:1 (0.87, 0.88, and 0.99 mg/culture), and VA (0.52, 0.56, and 0.62 mg/culture) were similar for the control, ETA, and DTA cultures, respectively. The concentrations of trans-C18:1 (5.51, 5.41, and 5.36 mg/culture), and VA (4.78, 4.62, and 4.59 mg/culture) were also similar between LA, ETALA, and DTALA cultures, respectively. These data suggest that C20:3n-3 and C22:3n-3 are not the active components in fish oil that promote VA accumulation when incubated with linoleic acid.     

奶粉脂肪酸与乳制品风味关系研究

用气质（GC—MS）联用色谱分析了11个商业奶粉样品的脂肪酸组成以及含量,每个样品均检测到了28种脂肪酸,在表现奶粉风味的4个呈味脂肪酸,也即辛酸、己酸、壬酸和葵酸中只检测到了辛酸和葵酸。辛酸和葵酸含量在进口奶粉中普遍高于国产奶粉。国产奶粉中辛酸和葵酸的含量以2号最好,3号其次。亚油酸含量在国产奶粉中普遍高于进口奶粉。     

气相色谱法同时快速测定食品中丙酸、山梨酸、苯甲酸及脱氢乙酸

通过液液萃取净化样品研究,建立了食品中丙酸、山梨酸、苯甲酸、脱氢乙酸及其盐含量气相色谱同时快速测定方法,适用于固体非酯(脂)类食品的检测。结果表明:丙酸的回收率在85.1%~91.3%之间,其余3种防腐剂的回收率均在95.2%~99.4%之间;实验室内变异系数(CV,n=6)最大值≤4.7%,4种防腐剂检出限均在0.002 g/kg以下。4种目标物在有杂质干扰时,可用不同的极性毛细管柱做进一步的确认。本方法具有适用范围广、检测效率高、重现性好、准确度高、检出限低的特点,推广应用对我国食品安全的监督检验具有重要的意义。     

花生四烯酸、二十二碳六烯酸和二十碳五烯酸 在炎症中的作用概述

心脑血管疾病、肿瘤、糖尿病、神经系统疾病、自身免疫等疾病严重危害着人类的生命和健康,并消耗着大量医疗资源。事实上,很多疾病发生和发展的背后都伴随着炎症反应,炎症是众多疾病的病理基础,甚至是导致这些疾病的诱因。炎症本身是机体的防御性反应,但过度的炎症反应和长期慢性炎症会损害机体的稳态。炎症的调节和控制由炎症介质介导,花生四烯酸(arachidonic acid,AA)、二十二碳六烯酸(docosahexaenoic acid,DHA)和二十碳五烯酸(eicosapentaenoic acid,EPA)等长链多不饱和脂肪酸(10ng-chain polyunsaturated fatty acids,LC-PUFAs)的衍生物是一类重要的调控炎症的介质。炎性细胞间的交流和细胞内信号传递与LC-PUFAs有关。AA经环氧酶和脂氧合酶合成的类二十烷酸主要起促炎作用,但有的也有抗炎作用。DHA和EPA在体内起抗炎作用,由它们合成的消退素(resolvins,Rvs)和保护素(protectin,PD)是重要的抗炎活性物质。DHA和EPA还可以干扰炎性细胞内信号传导途径来抑制炎症反应。本文从炎症与疾病的关系、LC-PUFAs的衍生物及其促炎和抗炎机制等方面综述了AA、DHA和EPA在炎症中的作用。     

Growth of Aeromonas hydrophila K144 as Affected by Organic Acids

The influence of different acids on the aerobic growth kinetics of Aeromonas hydrophila was studied in BHI broth with 0.5 and 2.0% NaCl incubated at 5 and 19°C. Growth curve data were analyzed by the Gompertz equation and a nonlinear regression program; generation and lag times were calculated from the Gompertz parameters. Type of acid, pH, NaCl level and temperature influenced lag and generation times. The organic acids (acetic, lactic, citric and tartaric) inhibited growth at higher pH values than inorganic acids (HCl and H₂SO₄). The high NaCl level interacted with type of acid and pH to restrict growth of the organism at the lower temperature of incubation. Acetic and lactic acids were effective in controlling the growth of A. hydrophila and could readily be combined with low holding temperature to render foods free of the organism.     

酸味酿造产品中三酸比例评析

酸味酿造产品中乳酸、醋酸、丁酸共存,但比例不同形成的酸味特征也不同。控制不同的环境条件,创造出不同的微生物区系,形成不同的三酸比例,才能形成不同的产品风格。该文对常见的酸味酿造产品中微生物区系的变化及三酸含量进行了分析。     

Anti-obesity effects of conjugated linoleic acid, docosahexaenoic acid, and eicosapentaenoic acid

Obesity has become a prevailing epidemic throughout the globe. Effective therapies for obesity become attracting. Food components with beneficial effects on "weight loss" have caught increasing attentions. Conjugated linoleic acid (CLA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) belong to different families of polyunsaturated fatty acids (PUFA). However, they have similar effects on alleviating obesity and/or preventing from obesity. They influence the balance between energy intake and expenditure; and reduce body weight and/or fat deposition in animal models, but show little effect in healthy human subjects. They inhibit key enzymes responsible for lipid synthesis, such as fatty acid synthase and stearoyl-CoA desaturase-1, enhance lipid oxidation and thermogenesis, and prevent free fatty acids from entering adipocytes for lipogenesis. PUFA also exert suppressive effects on several key factors involved in adipocyte differentiation and fat storage. Despite their similar effects and shared mechanisms, they display differences in the regulation of lipid metabolism. Moreover, DHA and EPA exhibit "anti-obesity" effect as well as improving insulin sensitivity, while CLA induces insulin resistance and fatty liver in most cases. A deeper and more detailed investigation into the complex network of anti-obesity regulatory pathways by different PUFA will improve our understanding of the mechanisms of body weight control and reduce the prevalence of obesity.     

杂多酸催化合成辛酸蔗糖酯

以蔗糖、辛酸为原料,杂多酸为催化剂合成辛酸蔗糖酯。用L16(45)正交设计优化实验,高效液相色谱法分析反应液组成。考察了催化剂种类和用量、反应温度、原料配比、反应时间等因素对辛酸蔗糖酯产率的影响,发现以二甲基亚砜为溶剂、蔗糖与辛酸摩尔比1∶9、磷钨酸用量为蔗糖质量的2.0%、110℃反应时间6h,蔗糖转化率达60%,产物产要是二酯。动力学研究发现,蔗糖反应级数为一级,反应表观速率常数为0.0059min-1(90℃)、0.0117min-1(110℃),反应表观活化能Ea=39.57kJ/mol。