不同包装方式对沙子空心李果干贮藏品质的影响

采用铝箔袋、真空袋、牛皮袋、自封袋、塑料袋、纸盒和塑料盒7种方式包装沙子空心李果干,于25℃贮藏6个月,并测定其水分含量、失重率、褐变指数、硬度、维生素C含量、可溶性糖含量、总酚含量、黄酮含量和菌落总数指标,研究不同包装方式对沙子空心李果干贮藏品质的影响,并筛选出最佳包装方式。结果表明：真空袋包装对沙子空心李果干的贮藏效果最好,其次为铝箔袋包装。     

贵州沿河沙子空心李果实营养分析与评价

为明确沙子空心李果实营养特性和引导消费,研究检测其接近完全成熟的果实果肉的24项营养成分指标。结果表明,有21项营养指标正常检出;其中,干物质、可溶性固形物、总糖等营养成分含量分别为11.8%、13.3%及8.8%,糖酸比为21.5,烟酸、多不饱和脂肪酸、碳水化合物、维生素D等营养素参考值均高于10%;受检16种氨基酸总量为0.494 g/100 g,必需氨基酸和鲜味氨基酸占比分别为30.2%和60.9%。沙子空心李营养物质种类丰富且总含量较高,酸甜可口,又具有特别的营养保健价值,是7月成熟的优质李品种。研究结果可作为沙子空心李果实营养的重要参考,也可为果实采后加工研究提供相关资料。     

低糖沙子空心李果脯的研制

以沙子空心李为主要原料,采用常温渗糖加工低糖沙子空心李果脯,探讨漂烫温度、木糖醇添加量、渗糖时间、干燥时间对低糖沙子空心李果脯感官品质的影响,通过单因素试验和正交试验优化得到低糖沙子空心李果脯的最佳工艺参数。结果表明,低糖沙子空心李果脯的最佳配方工艺为漂烫温度80℃,木糖醇添加量40%,渗糖时间12 h,干燥时间40 h,该条件下其组织饱满、硬度适宜、表面光泽、无返砂现象、酸甜可口。     

沙子空心李果实营养品质的主成分分析和综合评价

为今后切实有效评判沙子空心李的果实营养品质,该研究选取沙子空心李的6份果实样品(编号Kxl-1～Kxl-6)为试验材料,检测了其营养物质、生物活性成分和氨基酸组分的含量,评价了其氨基酸组分,并基于主成分分析进行了其果实营养品质的综合评价。沙子空心李果实营养物质含量为可溶性固形物12. 49%～13. 25%、可溶性糖6. 15%～10. 98%、可滴定酸2. 06%～3. 90%及可溶性蛋白66～85 mg/100g,生物活性成分为VC1.15～1.76 mg/100g、黄酮1. 15～1. 44 mg/100g及总酚0. 53～0. 77 mg/100g,各必需氨基酸总量为0. 669～1. 660g/100g;检测出了7种必需氨基酸,占氨基酸总量的比例为19. 57%～37. 01%。结果表明,能体现沙子空心李理化性状的主成分有3个,累积贡献率达87. 105%,影响第1主成分的有可溶性蛋白、VC、总酚、黄酮,影响第2主成分的为总氨基酸、可溶性固形物,影响第3主成分的为可溶性糖、可滴定酸。将果实品质进行综合评价并排序,Kxl-1、Kxl-2综合分值> 0. 7,品质较好。     

酶法提取沙子空心李多糖的工艺优化及稳定性研究

采用纤维素酶和果胶酶混合提取沙子空心李多糖,以多糖得率为指标,在单因素试验的基础上通过正交试验优化提取工艺,并研究其稳定性。结果表明：最优工艺条件为料液比1∶30(g/mL)、酶解温度50℃、酶解pH 6.5、混合酶添加量0.70%(以沙子空心李质量为基准),在此条件下沙子空心李多糖得率为22.26%;在低温(45～55℃)和中性条件下,沙子空心李多糖稳定性较好。     

不同工艺条件对沿河沙子空心李果脯品质的影响

以沿河沙子空心李为原料,探讨漂烫温度、漂烫时间、干燥温度、干燥时间、干燥方式、渗糖方式、食盐添加量对沿河沙子空心李果脯品质的影响。结果表明,漂烫温度为85℃、漂烫时间为3 min、干燥温度为60℃、干燥时间为35 h、常压热风干燥、超声波渗糖、食盐添加量为2.5%,沿河沙子空心李果脯呈棕褐色,色泽均匀,组织结构饱满,空心李果香味明显,口感细腻,含糖量较低,果脯品质最佳。     

6种鲜食葡萄营养成分比较分析

目的比较我国6种鲜食葡萄主栽品种营养成分的差异。方法采用理化分析方法对葡萄的氨基酸等营养成分进行测定,采用统计学方法比较分析品种间的营养差异。结果6种鲜食葡萄的脂肪、灰分、纤维、总酸、半胱氨酸、甘氨酸和磷含量差异不显著(P>0.05);夏黑葡萄的蛋白、总糖、还原糖、总花色苷、维生素C、必需氨基酸、风味氨基酸、支链氨基酸、药用氨基酸、增香与着色氨基酸、伯胺基氨基酸、K、Fe和Cu的含量均最高;巨玫瑰的总黄酮、总多酚、Ca、Mg和Mn的含量均最高;红地球的氨基酸比值系数评分和P含量最高,氨基酸营养均衡性最佳。结论不同品种鲜食葡萄营养差异明显,具有不同的潜在开发应用价值。     

5种沙梨主要营养成分分析

以5种沙梨为样品，用常规分析方法进行营养成分分析，原子吸收法选择测定了其中7种矿质元素含量，HPLC ACCQ.Tag法进行氨基酸的测定。结果表明：总糖的范围在5．00％～7.49％，蛋白质含量在0．11％～0.22％，Vc含量4．4～7.2mg/100g，总酸0.14％～0．34％；常量元素含量较高的是：钾(丰水)239.1mg／100g，镁(翠冠)21．88mg／100g；微量元素含量较高的是：Fe(清香)2．75mg／100g，Zn(翠冠)11.5mg／100g；含有16～17种氨基酸，其中有6～7种必需氨基酸。     

基于线性回归分析法预测李果实干制后果干糖酸比

目的:建立一种科学的预测鲜李制作成李干后糖酸比的预测模型。方法:以11种李果为实验材料,利用相关性分析、多元线性回归分析方法,探究鲜果22项理化品质指标与制作为果干后糖酸比的关系。结果:以果干糖酸比为因变量Y,鲜果22项指标为自变量X,经过逐步筛选挑选出5个重要影响因素:总糖（X1）、a*（X2）、镁（X3）、可滴定酸（X4）以及可食率（X5）,获得到多元线性回归方程Y=0.739+0.016X1-0.010X2+0.014X3-0.011X4-1.485X5 。回归方程决定系数R2为0.962,显著性F检验对应P值为0,有极显著影响（P＜0.01）。回归标准化残差分析结果显示,该方程符合正态分布,具有较高拟合度。结论:采用多元线性回归模型预测果干糖酸比可行性较高,预测结果较为精确,误差较低。     

红花苗营养成分的分析与评价

为阐明红花苗的营养价值,分析了国内外30种红花苗的蛋白质、粗纤维、抗坏血酸、可溶性糖、氨基酸、矿质元素等主要营养成分,通过与油菜、白菜等6中常见蔬菜对比及氨基酸比值系数法,综合评价红花苗蛋白质的营养价值。红花苗的蛋白质、抗坏血酸含量均明显高于6中常见蔬菜,属于高钾高钙低钠食品。红花苗中含有18种氨基酸和人体必需的8种氨基酸,氨基酸总量、必需氨基酸含量和非必需氨基酸的平均含量范围分别为17.49 g/100 g~20.03 g/100 g、6.650%~7.613%和10.483%~12.413%,变异系数分别为5.23%、6.40%和6.05%。30个参试品种必需氨基酸占氨基酸总量的比值（E/T）大多在36%~39%之间,略低于FAO/WHO理想蛋白标准;必需氨基酸与非必需氨基酸的比值（E/N）大多在58%~62%之间,接近并略高于FAO/WHO理想蛋白标准。氨基酸比值系数分60.25~76.40,蛋白质相对于鸡蛋标准蛋白的贴近度为0.90~0.93。必需氨基酸指数EAAI值均接近1。属于优质蛋白源。His、Ala、Arg、Asp、Glu、Phe这6种氨基酸使得红花苗呈现出不同的风味。参试红花苗均具有较高的营养价值,为可食用的优质蛋白源。     

Investigating the Antioxidant Potential of Turkish Dried Fruits

In this study, bio-active molecules of ten different dried fruits, which are widely consumed in Turkey, were investigated in terms of their flavonoid profile, antioxidant capacities, total phenolic, and total flavonoid contents. According to the results, all dried fruits possess an antioxidant activity at a certain level and have a different flavonoid profile with compounds belonging to the groups of flavonols, flavan-3-ols, anthocyanins, as well as chlorogenic acid. Dried cranberries and black raisins were observed to have the highest levels of total phenolics, flavonoids, and total antioxidant capacity. Especially black raisin samples were featured with their high amounts of catechin and epicatechin.     

二氧化硫抗氧化能力及其在干果中的含量分析

在前期干果品质分析时,发现部分干果的抗氧化能力异常,推测可能与二氧化硫有关。因此,该文采用了二苯代苦味酰基自由基(1,1-Diphenyl-2-picrylhydrazyl,DPPH)、2,2-联氮-(3-乙基苯并噻唑啉-6-磺酸)二氨盐自由基[2,2-diamine-(3-ethyl benzothiazolin-6-sulfonic acid)diammonate,ABTS]、铁离子还原能力(ferric reducing antioxidant power,FRAP)和氧自由基清除能力(oxygen radical absorbance capacity,ORAC)4种方法分析二氧化硫的抗氧化能力,同时测定8种新疆常见干果的二氧化硫含量。试验结果:在试验浓度范围内,二氧化硫具有一定抗氧化能力,1 mg二氧化硫相当于1μmol～2μmol 6-羟基-2,5,7,8-四甲基色烷-2-羧酸(6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid,Trolox)的抗氧化能力。此外,二氧化硫浓度与抗氧化能力呈线性相关,其中ORAC法的抗氧化能力最好(R^2=0.998 4);在8种干果中,黄提、枸杞、吊干杏、大无花果和小无花果中检出二氧化硫,其中,黄提(1.45 g/kg DW)和枸杞(0.18 g/kg)二氧化硫超过国家限量标准。这说明二氧化硫可能是导致部分干果抗氧化能力异常高的主要原因,因此在样品分析时,应考虑二氧化硫对样品指标的影响。     

产自攀枝花市的四种水果果干品质特性分析

本研究分析评价了芒果干、木瓜干、草莓干和桑葚干的主要营养成分,利用质地剖面法(Texture Profile Analysis,TPA)分析果干的内部结构,并结合感官和微生物学评价对果干的品质进行综合分析。结果表明,四种果干均为高糖产品,草莓干的可溶性糖和总糖含量最高,分别为55.66%和97.26%。桑葚干的蛋白质和风味氨基酸的含量均高于其他三种果干,且为典型的高K、低Na(K/Na为4827)食品。而芒果干中粗蛋白含量最低,但其EAA/NEAA高达55.51%,说明芒果干氨基酸组成较为合理。此外,木瓜干硬度、咀嚼性、内聚性均最大,果肉保持完整的能力最强,但适口性最差。最后,四种果干中重金属及致病菌等限量标准均未超标。本研究通过对产自攀枝花的四种果干品质特性进行分析,明确果干的各项指标,从而为果干的市场应用提供理论指导。     

火龙果的营养保健功效及开发利用

本文介绍火龙果的营养及药用价值，突出其保健功能，并对其在我国的开发潜力进行分析。     

金枪鱼鱼松的工艺研究

研究金枪鱼的营养成分、鱼肉脱腥方法,并研究了全营养金枪鱼鱼松加工工艺。因金枪鱼肉中脂肪含量高,使鱼肉制品存在鱼腥味,采用萃取法脱去鱼肉中的脂肪,去脂率高达95%。试验结果表明,金枪鱼富含蛋白质、DHA、EPA和矿物质;各因素对调味配方影响的主次顺序为:D>A>C>B,即最适宜的调味配方为盐1.5%、糖3.0%、大豆分离蛋白5.0%、姜汁3.0%、葱汁1%、味精1%、油3%;各因素对鱼松工艺影响的主次顺序为A>D>C>B,即最佳处理工艺为压榨水分55%,蒸煮时间75 min,初炒时间10 min。     

Performance of Drying Technologies to Ensure Microbial Safety of Dried Fruits and Vegetables

Dried fruits, vegetables, herbs, and spices are produced in and sourced from many countries worldwide, but they have been increasingly reported to be involved in outbreaks and alerts due to the presence of foodborne pathogens such as Salmonella. These dried products are mainly produced by solar drying and conventional air drying, but a wide range of drying technologies are available. From a technological point of view the general trend is to optimize and standardize the drying process to ensure high‐quality products to be offered. Drying technologies are mainly evaluated for their performance to reduce water activity at low energy cost while maintaining good sensorial quality of the dried product. However, as low water activity foods are increasingly recognized to support microbial survival and dried products are often consumed as they are, or are used as ingredients in many ready‐to‐eat foods, there is increasing attention to the microbiological quality and safety aspects of these products. This review presents traditional and emerging technologies to dry fruits, vegetables, herbs, and spices and discusses their potential to inactivate bacteria and viruses throughout the drying process. Overall, the microbial inactivation effect of the presented technologies has not yet been thoroughly assessed, even for traditional methods like solar drying, conventional air drying, or freeze‐drying. Emerging technologies such as dielectric (assisted) drying and low‐pressure superheated steam drying have been shown to reduce microbial populations; however, the number of studies is still low. Very few studies have focused on viral inactivation during drying processes.     

桑蚕干茧公证检验中抽样组批重量的分析

对同年度、同茧期、同庄口的桑蚕干茧公证检验规定报验批的关键指标检验结果与其对应实际货批检验结果综合平均值进行绝对差值和标准偏差统计分析,说明调整抽样组批重量的科学性和适用性.     

Chlorophyll-bound Magnesium in Commonly Consumed Vegetables and Fruits: Relevance to Magnesium Nutrition

ABSTRACT: Magnesium is bound as the central atom of the porphyrin ring of the green plant pigments chlorophyll a and b . It has been suggested that chlorophyll-bound magnesium may play an important role in magnesium nutrition because when iron is similarly bound in the porphyrin ring of heme, it is absorbed to a greater extent than non-heme iron. We have analyzed 22 frequently consumed fruits and vegetables for the chlorophyll content by high-pressure liquid chromatography and for magnesium with atomic absorption spectroscopy. Chlorophyll concentrations ranged from 6 μg/g (grape) to 790 μg/g (spinach) (median 63 μg/g). Magnesium concentrations ranged from 48 μg/g (grape) to 849 μg/g (spinach) (median 122 μg/g). In the green leafy vegetables, such as spinach and lettuce, chlorophyll-bound magnesium represented 2.5% to 10.5% of total magnesium whereas other common green vegetables, pulses and fruits contained < 1% chlorophyll-bound magnesium. The chlorophyll content of spinach was further decreased by about 35% on thawing frozen spinach or on chopping fresh spinach, and this degradation increased to about 50% after boiling and steaming. Based on the present results and published food consumption data, we estimate that chlorophyll-bound magnesium represents a very low fraction of total magnesium intake in industrialized countries, less than 1% in the case for data obtained from Switzerland. Thus, chlorophyll-bound magnesium is of little relevance to magnesium nutrition.