绿茶提取物对冷却羊肉保鲜作用的影响

为延长冷却羊肉的货架期,以云南圭山山羊肉为试验肉样,探讨不同浓度的绿茶提取物对冷却羊肉品质的影响。结果表明：提取物浓度为2%、4%、6% 的保鲜液均能有效抑制肠道菌群、假单胞菌和菌落总数的增长及挥发性盐基氮(TVB-N)和硫代巴比妥酸值(TBARS)的累积。2% 和4% 保鲜液处理的样品其色泽和感官评定值均显著优于对照组(p ＜ 0.05)。说明适当浓度的绿茶提取物可作为保鲜剂用于肉制品的贮藏。     

微酸性电解水结合迷迭香提取物对冷藏鲈鱼片品质变化的影响

为研究微酸性电解水结合迷迭香提取物(rosemary extract, RE)处理对鲈鱼片冷藏期间品质变化影响。将新鲜鲈鱼片随机分为4组,分别使用微酸性电解水(slightly acidic electrolyzed water, SAEW)[pH=6.35±0.04,氧化还原电位=(861.60±12.35) mV,有效氯浓度=(30.00±1.54) mg/L]、5.0 g/L RE、SAEW联合RE(SAEW处理5 min结合5.0 g/L RE浸渍5 min)处理10 min,以无菌水处理10 min为对照组(control, CK)。将4组样品处理后沥干,装入无菌聚乙烯保鲜袋中,置于4℃冷藏。每隔2 d进行微生物[菌落总数(total viable count, TVC)、嗜冷菌数(psychrophilic bacteria count, PBC)]、理化指标[pH值、总挥发性盐基氮(total volatile basic nitrogen, TVB-N)值、硫代巴比妥酸(thiobarbituric acid, TBA)值、质构分析]与感官评定等指标测定,并结合持水力(...     

生姜提取物的抗菌特性及其在冷却肉保藏中的应用

研究生姜提取物的抑菌作用,测定生姜提取物对冷却肉中常见菌大肠杆菌、金黄色葡萄球菌、清酒乳杆菌、假单孢菌的抑菌圈和最低抑菌浓度.将冷却猪肉用不同浓度的生姜提取液处理,普通包装后置于(4±1)℃保存,分别于第0,3,6,9,12天测定其细菌总数.结果表明生姜提取物具有较强的抑菌作用,2%-4%的生姜提取液能有效地延长冷却猪肉的货架期.     

迷迭香提取物对等离子体处理鸡胸肉饼脂质氧化及品质影响研究

研究了不同浓度迷迭香提取物(RE)对包装内介质阻隔放电(DBD)冷等离子体(CP)处理的鸡胸肉饼脂质氧化及品质特性的影响。鸡肉饼在70 kV条件下DBD-CP处理180 s,在4 ℃贮藏的第0天和第5天测定菌落总数、pH值、颜色和脂质氧化。结果表明,CP处理在0 d时对鸡肉饼的菌落总数无影响,但贮藏5 d后,CP处理使菌落总数显著降低,同时CP处理也加剧了鸡肉饼的脂质氧化。添加0.2%和0.3% RE可降低CP处理和非CP处理鸡肉饼的菌落总数,各浓度RE对CP处理和非CP处理鸡肉饼脂质氧化均有抑制作用,且浓度越高,效果越好。添加RE使鸡肉饼的L*值降低而a*值和b*值升高,添加0.3% RE使鸡肉饼pH值降低。综上所述,迷迭香提取物可用于抑制CP加工肉类的微生物生长,同时能控制脂质氧化,具有较好的应用前景。     

葡萄皮渣提取物-壳聚糖复合涂膜对冷鲜猪肉贮藏品质的影响

为提高冷鲜猪肉贮藏品质,延长冷鲜猪肉的货架期,制备了葡萄皮渣提取物-壳聚糖复合涂膜,研究壳聚糖与不同浓度(60%、80%和100%)葡萄皮渣提取物复合涂膜对冷鲜猪肉贮藏品质的影响。在4℃的冷藏环境下,选择未经涂膜处理、壳聚糖涂膜和复合涂膜3种方法处理猪肉样品,并贮藏10 d,测定其pH值、肉样汁流失率、硫代巴比妥酸反应物值、挥发性盐基氮值以及感官品质。结果表明,葡萄皮渣提取物的添加可产生一定的浓度效应,浓度为80%和100%的葡萄皮渣提取物-壳聚糖复合涂膜显著延缓了冷鲜猪肉的pH值上升和脂质过氧化,降低汁液流失率,维持良好的感官品质,同时作用效果优于单一壳聚糖涂膜,可有效保证冷鲜猪肉的贮藏期达10 d以上,为冷鲜猪肉贮藏、远距离运输和销售提供有力保障。     

香辛料提取物对乳化香肠抗氧化作用的研究

研究香辛料提取物在乳化香肠中的添加效果,讨论不同浓度与不同品种的香辛料提取物对香肠品质影响,并通过正交试验以及模糊数学方法的感官评定,确定当香辛料提取物丁香为1.5%、连翘1.0%、桂皮1.5%时抗氧化效果最好.     

大蒜提取物对冷藏蔬菜鱼丸品质的影响

研究蔬菜鱼丸中添加不同量的大蒜提取物(0、100、150、200mg/kg)后在4℃冷藏条件下的品质变化。每5d取鱼丸样品的分析感官特性(感官评分、质构和白度)、微生物(细菌总数)和理化(pH值、TVB-N值和TBA值)等指标。结果表明：添加大蒜提取物的处理组保鲜效果明显优于对照组,其中大蒜提取物添加量在200mg/kg时,保鲜效果最佳,其货架期延长了7～8d。通过处理组与对照组细菌总数、pH值、TBA、TVB-N等品质指标的比较可知,大蒜提取物在鱼丸冷藏保鲜过程中能有效地抑制细菌生长,并减缓蛋白质、脂肪等氧化变质,从而延长了鱼丸的货架期。     

乳酸链球菌素和迷迭香提取物对调理切片羊肉保鲜效果研究

为研究乳酸链球菌素（Nisin）和迷迭香提取物（rosemary extract,RE）对调理切片羊肉保鲜效果的影响，本实验设置了对照组、真空包装组、Nisin(0.1、0.3、0.5 g/kg Nisin)、RE(0.1、0.2、0.3g/kg RE)8种处理方式，分析不同处理的调理切片羊肉在冷藏过程中感官评价、色差值、pH、TVB-N含量、TBARS值和羰基含量等品质指标变化。结果表明：不同处理方式对调理切片羊肉的色差值影响较小；0.3g/kg RE处理组相较于其他处理组（除真空包装处理组外）有较高的感官评分（P <0.05）和较低TBARS值（P <0.05）及羰基含量（P <0.05）;0.5 g/kg Nisin处理组的TVB-N含量最低（P <0.05）,0.3 g/kg Nisin和0.3 g/kg RE处理组次之。综上，0.3 g/kg RE处理组调理切片羊肉能够在冷藏过程中保持较高的氧化稳定性和较好的新鲜度。     

丝兰提取物对奶牛人工瘤胃发酵指标的影响

试验采集荷斯坦奶牛的瘤胃液,进行体外发酵试验。探究在培养底物中添加不同水平的丝兰属植物提取物（0%、0.3%、0.6%、1.2%和2.4%）对2、6、12、18和24 h产气量及24 h培养液pH值、氨态氮浓度、菌体蛋白浓度和干物质降解率的影响。结果表明：添加不同水平丝兰属植物提取物处理组6、18和24 h的产气量均低于对照组,18 h时2.4%丝兰属植物提取物处理组产气量显著低于对照组和0.3%丝兰属植物提取物处理组;24 h时1.2%和2.4%丝兰属植物提取物处理组产气量显著低于对照组。2.4%丝兰属植物提取物处理组氨态氮浓度显著低于对照组。丝兰属植物提取物对干物质降解率、pH值以及菌体蛋白浓度没有显著影响。     

冷链条件下马鲛鱼优势腐败菌生长动力学研究及货架期预测

为快速预测冷链马鲛鱼在不同冷链物流温度下优势腐败菌生长动态及货架期,进行了马鲛鱼0,4,10℃下3种典型冷链温度的贮藏模拟试验,分析了马鲛鱼不同温度下的菌落总数、希瓦氏菌数和假单胞菌数以及各个温度下马鲛鱼货架期终点时的挥发性盐基氮含量和感官评定质量指数,采用修正的Gompertz和Belehradek方程建立了冷链马鲛鱼中优势腐败菌在0~10℃的一级、二级生长预测模型与货架期预测模型。结果表明,修正的Gompertz方程能准确表达马鲛鱼在3种贮藏温度下假单胞菌的生长规律,拟合度R^2高达0.99,采用Belehradek方程描述温度对最大比生长速率(μ_max)和延滞期(λ)的影响呈现良好的线性关系,相关性R^2>0.90。进一步用贮藏于2,8℃马鲛鱼中假单胞菌数来验证模型的可靠性,偏差度为1.010 4~1.024 5,准确度为1.026 8~1.038 7,货架期预测模型的相对误差绝对值为6.09%~8.95%。     

生姜、洋葱、丁香提取物对猪肉的保鲜效果

以蒸馏水处理的猪肉为对照,研究生姜、洋葱、丁香提取物及其等体积混合制成的混合液以及化学防腐剂2,6-二叔丁基-4-甲基苯酚对猪肉保鲜效果的影响。用体积分数95%的乙醇浸提其中的有效成分,冷却猪肉分别在各组保鲜液中浸泡4min,沥干后用聚乙烯保鲜袋密封包装,最后在4℃冰箱冷藏12d,每3d测定1次感官评分、汁液流失率、蒸煮损失率、色度值、pH值、剪切力、总挥发性盐基氮（total volatile basic nitrogen,TVB-N）含量。结果表明：洋葱、生姜和丁香提取物均能够有效延长猪肉的贮藏时间,其中,生姜、洋葱、丁香混合提取物效果最佳,猪肉感官评分最高,汁液流失率和蒸煮损失率最低,色度值最好,pH值最低,剪切力最小,TVB-N含量最小,可将猪肉的保质期延长到12d。     

麦芽提取物在发酵饮料中的应用

麦芽提取物是一种完全源自谷物的天然食品,它含有丰富的麦芽糖、果糖、葡萄糖、蛋白质、小分子肽、人体必须的氨基酸和多种维生素、矿物质,还含有具有保健功能的β-葡聚糖和生育酚。用麦芽提取物生产的麦芽汁发酵饮料营养丰富,风味浓郁、独特、醇厚。与传统麦芽汁发酵饮料生产工艺相比,生产过程不需要糖化,从而使得工艺更为简单,生产周期更短,设备投入减少,降低了成本。     

Effect of addition of commercial rosemary extracts on potent odorants in cooked beef

Solid-phase microextraction-gas chromatography-olfactometry (SPME-GCO) and aroma extract dilution analysis (AEDA) were applied to measure the effects of the addition of two commercial rosemary extracts (RE) on the potent odorants in cooked beef extracts (BE). On the basis of the results of SPME-GCO and AEDA, the addition of RE imparted sweet and floral notes to BE as a result of the addition of esters and terpenes of RE. In addition, RE suppressed the formation of odorants derived via lipid oxidation and Maillard reactions. The most potent lipid oxidation volatiles consisted of 1-octen-3-one (mushroom-like), (E)-2,4-epoxy-(E)-2-decenal (metallic), and eight different aldehydes (fatty). The Maillard reaction volatiles, necessary for typical cooked beef flavor, included compounds with meaty [2-methyl-3-furanthiol, 2-methyl-3-(methylthio)furan, 2-methyl-3-(methyldithio)furan], roasty (2-furanmethanethiol), caramel-like [4-hydroxy-2,5-dimethyl-3(2H)-furanone], baked potato-like [3-(methylthio)propanal], and spicy [3-hydroxy-4,5-dimethyl-2(5H)-furanone] attributes. The suppressive effects of RE may be caused by the action of antioxidative substances in RE alone or in combination with the pH increase in BE induced by the matrix components of RE.     

柚子皮中抗过敏活性粗提物提取工艺的研究

对柚子皮抗过敏活性成分进行提取,通过单因素试验研究乙醇浓度、提取时间、提取温度、料液比和提取次数等提取条件对提取效果的影响,并通过正交试验优化其提取工艺,确定最佳提取条件为:乙醇浓度80%,提取时间45 min,提取温度为50℃,料液比1∶30(g/mL),提取次数为2次。在此条件下进行验证试验,透明质酸酶抑制率达到22.51%。     

两性植物鞣剂的制备及其鞣制性能的研究

本文初步探讨了利用亚硫酸化和Ｍａｎｎｉｃｈ反应制备两性植物鞣剂的方法及两性鞣剂的鞣性。结果表明，两性植物鞣剂使用ｐＨ值范围广，不易被空气氧化，具有明显的缩毛孔作用。用其鞣制的植鞣猪皮软面革，柔软、丰满、有弹性、粒面效果好。     

牛肉汁致突变性的研究

在用鼠伤寒沙门氏菌(Salmonella typhimurinm)雨株TA 98研究了熬煮牛肉汁的致突变性。结果表明,牛肉汁的致突变性水平取决于熬煮的时间和浓度,而与其色度无关。     

Retention of the Enzymatic Activity and Product Properties During Spray Drying of Pineapple Stem Extract in Presence of Maltodextrin

The aim of this work was to investigate the effects of drying parameters on the retention of the enzymatic activity and on the physical properties of spray-dried pineapple stem extract. A Box and Behnken experimental design was used to investigate the effects of the processing parameters on the product properties. The parameters studied were the inlet temperature of drying gas (Tgi), the feed flow rate of the pineapple extract relative to evaporative capacity of the system (W_s?/W_max), and the concentration of maltodextrin added to the extract (MD). Significant effects of the processing parameters on the retention of the proteolytic activity of the powdered extract were observed. High processing temperatures lead to a product with a smaller moisture content, particle size, and lower agglomerating tendency. A product with insignificant losses of the proteolytic activity (≈ 10%) and low moisture content (less than 6.5%) is obtained at selected conditions.     

Examination of the Relationships Between Original,Real and Apparent Extracts,and Alcohol in Pilot Plant and Commercially Produced Beers

The historical development of equations used to relate alcohol and real extract to apparent extract and original gravity, as well as ratios between the corrected Real (RDF) and Apparent Degrees of Fermentation (ADF), were examined in light of modern polynomial and non‐linear regression techniques. Comparisons were performed using an extensive data set of 532 brews obtained from commercial and pilot fermentations with statistical error analysis of these empirical relationships. New predictions of apparent extract were calculated as a function of alcohol and real extract analogous to the Improved Tabarie's formula. In addition, attempts at improving Balling's original equation model estimating original gravity from alcohol and real extract are detailed and discussed. The statistical analyses of relationships between A_w/w (alcohol by weight) and functions of OE (Original Extract), AE (Apparent Extract) and RE (Real Extract) as well as ratios between the corrected Real and Apparent Degrees of Fermentation (RDF/ADF) are reported. It is expected that this paper will be useful for brewers to more accurately estimate A_w/w and real extract values.     

Addition of grape seed extract and bearberry to porcine diets: Influence on quality attributes of raw and cooked pork

The effect of supplementation of pig diets with grape seed extract (GSE) (100, 300, 700 mg/kg feed) and bearberry (BB) (100, 300, 700 mg/kg feed) for 56 days pre-slaughter, on the oxidative stability and quality of raw and cooked M. longissimus dorsi (LD) was examined. Susceptibility of porcine liver, kidney and heart tissue homogenates to iron-induced (1 mM FeSO₄) lipid oxidation was also investigated. In raw LD steaks, stored in modified atmosphere packs (75% O₂:25% CO₂) (MAP) for up to 16 days at 4 °C, surface lightness (CIE ‘L’ value), redness (CIE ‘a’ value), lipid stability (TBARS, mg MDA (malondialdehyde)/kg muscle) and pH were not significantly affected by supplemental GSE or BB. Similarly, the oxidative stability and sensory properties of cooked LD steaks, stored in MAP (70% N₂:30% CO₂), for up to 28 days at 4 °C, were not enhanced by dietary GSE or BB. Iron-induced lipid oxidation increased in liver, kidney and heart tissue homogenates over the 24 h storage period and susceptibility to oxidation followed the order: liver > heart > kidney. Dietary GSE or BB did not significantly reduce lipid oxidation in tissue homogenates. Potential reasons for the lack of efficacy of supplemental GSE and BB on pork quality were explored.     

酶解型天然鲍鱼提取物在"鲍鱼汁"生产中的应用

利用酶解型天然鲍鱼提取物,经合理的调配,可生产出风味天然纯正的新型调味品--鲍鱼汁.