Millet Grains: Nutritional Quality,Processing, and Potential Health Benefits

In the 21st century, climate changes, water scarcity, increasing world population, rising food prices, and other socioeconomic impacts are expected to generate a great threat to agriculture and food security worldwide, especially for the poorest people who live in arid and subarid regions. These impacts present a challenge to scientists and nutritionists to investigate the possibilities of producing, processing, and utilizing other potential food sources to end hunger and poverty. Cereal grains are the most important source of the world's food and have a significant role in the human diet throughout the world. As one of the most important drought‐resistant crops, millet is widely grown in the semiarid tropics of Africa and Asia and constitutes a major source of carbohydrates and proteins for people living in these areas. In addition, because of their important contribution to national food security and potential health benefits, millet grain is now receiving increasing interest from food scientists, technologists, and nutritionists. The aim of this work was to review the recent advances in research carried out to date for purposes of evaluation of nutritional quality and potential health benefits of millet grains. Processing technologies used for improving the edible and nutritional characteristics of millet as well as challenges, limitations, and future perspectives to promote millet utilization as food for a large and growing population are also discussed.     

符离集烧鸡加工过程中的营养和理化品质变化

通过对符离集烧鸡在5个不同加工阶段下主要成分、pH、嫩度、食盐、总糖、氨基酸含量等的测定,探究其在加工过程中营养和理化品质的变化。结果表明,在加工过程中,鸡胸肉和鸡腿肉的水分含量、剪切力显著下降(P<0.05),灰分、蛋白质、脂肪以及食盐含量显著增加(P<0.05);卤制后鸡胸肉(pH=6.45)和鸡腿肉(pH=6.65)的pH达到最大,杀菌后有所下降;油炸时鸡胸肉和鸡腿肉总糖含量分别增加了75.34%和72.62%(P<0.05),卤制和杀菌后鸡肉的总糖含量下降。烧鸡加工过程中共检出17种氨基酸,其中谷氨酸(16.31%~17.11%)、天冬氨酸(9.53%~10.42%)、亮氨酸(8.16%~8.53%)、赖氨酸(8.48%~9.10%)是烧鸡中最主要的氨基酸,谷氨酸的含量最高。除苯丙氨酸外,成品烧鸡中必需氨基酸均高于FAO/WHO/UNU推荐含量,可见烧鸡具有较高的营养价值。卤制对烧鸡其营养品质影响较大,杀菌保证了产品安全性的同时,对其营养及理化品质无不良影响。     

大鲵汤加工过程中营养品质变化规律

分析大鲵汤加工过程中营养品质的变化规律。测定5个不同熬煮时间(30、60、90、120、150 min)条件下大鲵汤的一系列营养指标,包括可溶性蛋白质含量、粗脂肪含量、可溶性固形物含量、肌苷酸含量、定性定量脂肪酸组成和游离氨基酸组成。结果表明:大鲵汤中可溶性固形物与可溶性蛋白质含量在30~60 min间显著增加,在60~120 min间趋于平衡,在120 min后显著增加;肌苷酸含量随熬煮时间延长而增加;测得以棕榈酸、十六烯酸、油酸、亚油酸、花生四烯酸和二十四碳烯酸为主的16种脂肪酸,且饱和脂肪酸和多不饱和脂肪酸比值(saturated fatty acids/polyunsaturated fatty acids,SFA/PUFA)呈现出先减小后增大的趋势,在60 min时粗脂肪含量和脂肪酸含量适宜,且SFA/PUFA值最佳为1.37;大鲵汤中总氨基酸含量、必需氨基酸含量、鲜味氨基酸含量、必需氨基酸与非必需氨基酸比值(essential amino acid/non-essential amino acid,EAA/NEAA),随熬煮时间的延长先上升后下降,在60 min时达到峰值,总氨基酸含量为239.529 mg/100 g,EAA/NEAA值为0.858。在传统的常压熬煮条件下,熬煮时间为60 min时大鲵汤营养品质好,此时汤中脂肪含量适宜且SFA/PUFA值最佳,氨基酸含量最高。     

燕麦片加工过程中营养品质及加工特性变化

为探讨燕麦片加工过程的主要营养成分变化,本试验于商品化燕麦片不同生产环节在线取样,分析蒸煮、烘干和微波烘烤等工艺对燕麦中营养品质及加工特性的影响。结果表明:加工不会导致燕麦蛋白质、脂肪和β-葡聚糖含量发生显著变化,但蒸煮和烘干后总酚含量分别降低5.11%和11.57%(P0.05)。加工过程中燕麦脂肪酸组成没有显著变化,糊化温度、最终黏度、崩解值和回生值显著降低;蒸煮能完全钝化脂酶活性,蒸煮和微波烘烤后燕麦蛋白质消化率显著提升6.78%和13.25%,微波烘烤导致燕麦β-葡聚糖主要组分分子质量降低6.92%。研究结果表明燕麦片加工过程中营养成分含量变化较小,但黏度特性指标降低及蛋白消化率提高,使其更有利于人体吸收与利用。     

不同米色小米营养品质与蒸煮特性研究

为探明不同米色小米间品质差异,本文选取5种具有色差代表性的小米(沁州黄、黄金苗米、白小米、黑小米和绿小米)进行研究。对原花青素、多酚、矿物质等营养成分,直链淀粉、糊化温度、胶稠度蒸煮特性进行测定分析。营养品质研究结果表明不同米色小米之间差异较大,深色小米(绿小米、黑小米)原花青素含量分别为0.295、0.261 mg/g,显著(P<0.05)高于其他米色小米,黄色小米(沁州黄、黄金苗米)总胡萝卜素含量在1.98~2.07 μg/g之间,显著(P<0.05)高于其它米色小米。黄色小米(沁州黄、黄金苗米)易于糊化,蒸煮品质较好,直链淀粉含量在28.53~29.01 mg/g之间,糊化温度在87.60~88.45 ℃之间,显著(P<0.05)低于其它米色小米,胶稠度在93.26~94.85 mm之间,显著(P<0.05)高于其他米色小米。相关性分析表明小米中总胡萝卜素与直链淀粉含量、糊化温度显著(P<0.05)负相关,相关系数为-0.96、-0.98,与胶稠度显著(P<0.05)正相关,相关系数为0.97。     

小米挤压粉与小米生粉理化性质及营养品质的差异比较

为了全面分析挤压膨化处理对小米粉品质特征的影响,本文系统比较了小米挤压粉与小米生粉理化性质及营养品质的差异,结果发现:小米挤压粉的密度极显著低于小米生粉(P<0.01),而粒径(P<0.01)和静止角(P<0.01)极显著高于小米生粉。挤压膨化后,小米挤压粉亮度(L^*)减小、色泽(a^*)变暗、肉眼可观察到色泽的差异。挤压膨化过程中产生较多阈值较低,风味贡献较大的醛类、呋喃类和吡嗪类挥发性风味物质,使得小米挤压粉的风味明显优于小米生粉。醛类,尤其是己醛(其相对质量分数高达34.58%),是小米挤压粉的主要风味贡献物质。与小米生粉相比,小米挤压粉的干基脂肪含量和直链淀粉含量分别减少28.92%和28.21%,但多不饱和脂肪酸含量增加21.08%,其中亚油酸增加19.92%、亚麻酸增加63.40%。据此推测,适量添加小米挤压粉将有利于增强小米制品的风味、改善成品口感、提高成品质量。     

主栽大豆营养品质及加工特性初探

为考察我国主栽大豆的营养品质和初步探究其相应加工特性,本研究收集主栽大豆品种8种,通过测定其营养成分、活性物质含量及分离蛋白组成,结果显示我国主栽大豆品种具有高蛋白、高脂肪、低碳水化合物、高膳食纤维的营养特点和较广泛加工特性。吉科鲜豆、吉科育种08、690属于高蛋白质大豆,吉科鲜豆、吉科密豆、黑农51号、东升7号、农垦9号为1级高油大豆。大豆样品维生素E、钙、铁含量丰富,分别为11.0~21.8 mg/100 g、560.0~1270.0 mg/kg、66.20~83.40 mg/kg。维生素B₂含量在各品种间差异较小,而异黄酮含量差异较大。8个主栽大豆品种中7S、11S蛋白含量以及分离蛋白聚集体粒径的变异系数均在30%以上,不同品种间大豆加工特性具有较大差异。     

Tuna Protein Nutritional Quality Changes after Canning

Albacore tuna (Thunnus alalunga) was steamed and canned in soy bean oil and sterilized at 115°C for 55 or 90 min. Proximate composition, total amino acid and available lysine content were determined during different phases of the process. Water and protein were lost in all phases and fat content increased. There was a decrease in available lysine during cooking but no loss in total amino acids. Nutritional evaluation of the protein showed differences in biological value and net protein utilization when the canned tuna was mixed with bread flour.     

猕猴桃等添加物改良面条加工品质及强化营养品质研究

为改善面条加工品质和强化营养品质,以陕优225小麦品种粉为面条粉材料,以猕猴桃粉、核桃粉、大豆粉为添加材料,研究添加物对面条加工品质和营养品质的影响;以国际通行的优质面条专用技术标准为依据,进行新的工艺研究。试验结果表明,添加物在一定程度上可以改善面条品质,尤其能够丰富面条的营养物质,改善和强化面条的营养品质。在单因素试验中,猕猴桃粉、核桃粉和脱脂大豆粉效果较好。在以上3种添加物为因素的正交试验中,大豆粉对面条影响最大,核桃粉次之,猕猴桃粉的影响最小,3种添加物最佳配比是猕猴桃粉添加量为面粉的3%,核桃粉为4%,大豆粉为4%。     

Instant Noodles: Processing,Quality, and Nutritional Aspects

Noodles are one of the staple foods consumed in many Asian countries. Instant noodles have become internationally recognized food, and worldwide consumption is on the rise. The properties of instant noodles like taste, nutrition, convenience, safety, longer shelf-life, and reasonable price have made them popular. Quality factors important for instant noodles are color, flavor, and texture, cooking quality, rehydration rates during final preparation, and the presence or absence of rancid taste after extended storage. Microstructure of dough and noodles has been studied to understand the influence of ingredients and processing variables on the noodle quality by employing scanning electron microscopy. Applications of newer techniques like confocal laser scanning microscopy and epifluorescence light microscopy employed to understand the microstructure changes in dough and noodles have also been discussed. Sincere efforts of researchers are underway to improve the formulation, extend the shelf life, and promote universal fortification of instant noodles. Accordingly, many researchers are exploring the potential of noodle fortification as an effective public health intervention and improve its nutritional properties. This review focuses on the functionality of ingredients, unit operations involved, quality criteria for evaluation, recent trends in fortification, and current knowledge in relation to instant noodles.     

西农黑大穗黑小麦营养特性与蒸煮食品加工品质评价

以黑小麦品种西农黑优为对照,研究西农黑大穗黑小麦的营养特性及蒸煮加工品质。结果表明:西农黑大穗千粒质量50.81g,高于西农黑优;灰分含量2.38%、蛋白质含量16.49%、总氨基酸含量13.12%,均高于西农黑优;面条感官评价得分84.63,馒头感官评价得分78.07。西农黑大穗黑小麦具有良好的面条加工性能,作为一种黑色食品新原料具有良好的开发前景。     

Changes in the Hydrophobicity and Functionality of Whey during the Processing of Whey Protein Concentrates

Cheddar cheese whey was ultrafiltered to yield whey protein concentrates (80% WPC). The retentates were heated at 64 or 72°C for 1.5 set or received no heat treatment. Changes in composition and hydrophobicity during processing were related to WPC functionality. Heating at 72°C decreased retentate hydrophobic@ and had a detrimental affect of WPC functionality, while heating at 64°C did not. Day to day variation in the milk supply and processing conditions did not affect hydrophobicity; but the unit operations did have an effect. Ultrafiltration increased the alkane binding values of the retentate compared to the whey. Spray drying the retentate increased surface hydrophobicity and decreased alkane binding values of the WPC.     

小麦苗营养保健果冻的研制

以小麦苗为主要原料,通过正交试验对麦苗果冻复合胶的最佳配比和果冻最佳配方进行了研究。复合胶的最佳配比为:卡拉胶0.3%、琼脂0.1%、魔芋胶0.3%;麦苗保健果冻的最佳配方为:复合胶0.7%、麦苗汁30%、糖15%、β-环糊精1.0%。按此配方制作的果冻呈浅绿色,爽滑可口,富含多种维生素和矿物质。     

种植地点和加工精度对小米营养与安全品质的影响

为了解种植地点和加工精度对小米营养及安全品质的影响,选取4个种植地点的济谷19谷子,分别加工成糙米和精米,粉碎测定水分、脂肪、淀粉、黄色素、氨基酸、矿质元素硒、铁、铅、镉等指标。结果表明种植地点对小米脂肪、淀粉、黄色素含量影响显著。加工精度显著影响小米脂肪、淀粉、氨基酸含量,对黄色素含量影响不显著;脂肪、氨基酸含量精米显著低于糙米;淀粉含量精米显著高于糙米。不同种植地点小米矿质元素硒、铁、铅、镉含量差异显著;加工精度显著影响小米铁、铅、镉含量,铁、铅、镉含量精米显著低于糙米。控制加工精度可以减少小米脂肪、氨基酸、铁等营养成分损失;利用自然禀赋条件可以生产营养强化型小米。     

谷子萌芽期营养品质变化及氨基酸组分评价

通过对萌芽期谷子营养成分变化的分析,进而改善谷子的食用品质,以期提高谷子的营养价值。以萌芽全谷和萌芽小米为研究对象,全面探究萌芽对谷子和小米中淀粉理化特性、营养物质(蛋白质、氨基酸、脂肪、矿物质、维生素等)的变化,评价萌芽对其食用品质的影响。结果表明:萌芽后的谷子和小米的淀粉含量均升高,黏度处理均表现出"高崩解值,低回生值"的趋势;萌芽后的谷子和小米的蛋白质和脂肪含量均下降,而游离氨基酸含量变化不一,通过模糊识别法、氨基酸比值系数等方法对氨基酸组分进行评价,得出萌芽后的谷子和小米的氨基酸含量更加丰富,且与联合国粮农组织/世界卫生组织(Food and Agriculture Organization of the United Nations/World Health Organization,FAO/WHO)提出的标准模式更加相近;萌芽全谷中主要矿物质和维生素含量总体呈现上升趋势;萌芽小米中钙、锌、V_(B_1)和β-胡萝卜素有所增加,而铁、硒、V_(B_2)和V_E有所减少。萌芽全谷和萌芽小米的营养成分均发生不同程度的变化,可为萌芽谷子和萌芽小米地深入研究提供理论参考依据,也为全谷物营养+、萌芽谷子和小米主食化、深加工产品研发奠定良好基础。     

乌龙茶加工过程中儿茶素的稳定性及化学变化

研究半发酵乌龙茶加工对活性化学成分儿茶素的影响。采摘的鲜叶立即在严格控制的加工条件下进行加工,分析每道加工工艺操作所制茶叶的儿茶素总量和各种儿茶素单体(－)-儿茶素、(－)-表没食子儿茶素、(＋)-儿茶素、(－)-表儿茶素、(－)-表没食子儿茶素没食子酸酯、没食子儿茶素没食子酸酯、(－)-表儿茶素没食子酸酯、(－)-儿茶素没食子酸酯的含量。研究表明,在乌龙茶加工过程中,儿茶素总含量略有下降,约为10%;儿茶素单体变化不一。在加工工艺中,做青、杀青和干燥对儿茶素含量影响较大。为使乌龙茶中儿茶素的潜在健康效益最大化,这3 道工艺应在茶叶生产中加以考虑并做到最优化,以期为乌龙茶加工研究提供一定的参考依据。     

枇杷果汁加工过程中产品品质的变化

在枇杷果汁加工过程中,对鲜果以及护色、打浆、酶解、过滤和调配等工艺环节处理后,分别取样测定其色差值、可滴定酸、可溶性固形物、总酚和黄酮的含量以及对2,2’-联氮-二（3-乙基-苯并噻唑-6-磺酸）二铵盐自由基（2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) free radical,ABTS＋·）清除率,并采用顶空固相微萃取结合气相色谱-质谱分析技术,对挥发性物质进行富集、分离和鉴定,研究枇杷果汁加工过程中产品品质的变化。结果表明,枇杷果汁加工过程中的总色差值呈先升高后下降的趋势,其中酶解后其色差值最大;可溶性固形物和可滴定酸含量总体上先呈下降趋势,经调配处理后极显著上升;总酚和总黄酮含量以及对ABTS＋·清除率呈现下降趋势。从枇杷加工不同环节产品中鉴定出的挥发性化合物以醇类、醛类和酯类为主。主成分分析结果表明,枇杷鲜果、护色及调配后的产品具有较好的营养、口味、香气品质以及抗氧化性能,而打浆、酶解和过滤环节都在不同程度上严重降低了产品品质。     

红小米化学成分与营养成分分析

为探究河南南阳红小米的物质基础,以不同年份南阳红小米为原料,采用组织破碎法提取、硅胶色谱层析法结合结晶沉淀法纯化及常规的营养成分分析方法,对红小米的化学成分和营养成分进行分析,同时以芹菜素为标准品,采用亚硝酸钠-硝酸铝-氢氧化钠显色法测得红小米中总黄酮含量。首次从红小米中分离得到香草醛、香草酸、β-谷甾醇、邻苯二甲酸二丁酯、芹菜素共5 个化合物;测得的总黄酮质量分数为4.91%;同时研究结果表明,红小米中氨基酸种类丰富,必需氨基酸-总氨基酸、必需氨基酸-非必需氨基酸之比分别为39.49%、60.51%,数据接近联合国粮农组织及世界卫生组织的理想模式;脂肪酸主要有棕榈酸、亚油酸、油酸、硬脂酸等,其中亚油酸含量最高（64.60%）;维生素中γ-VE含量较高（2.24 mg/100 g）;微量元素中Mg和P含量最高,分别为2 160、3 470 mg/kg。     

Pulsed Electric Field Processing of Orange Juice: A Review on Microbial,Enzymatic, Nutritional,and Sensory Quality and Stability

During the last decades pulsed electric field (PEF) processing received considerable attention due to its potential to enhance food products or create alternatives to conventional methods in food processing. It is generally acknowledged that PEF processing can deliver safe and chill‐stable fruit juices with fresh‐like sensory and nutritional properties. Relatively low‐processing temperature and short residence times can achieve highly effective inactivation of microorganisms while retaining product quality. A first commercial application of PEF for preservation of fruit juices was launched in 2006 in the United States. Since then, industrial‐scale processing equipment for liquid and solid products were developed and, in Europe in 2009, an industrial juice preservation line was installed using 20 kV/cm pulses at 40 to 50 °C to extend the chill‐stability of fruit juices, including citrus juices and smoothies, from 6 to 21 d. The related PEF processing costs are in the range of US $0.02 to 0.03 per liter and are justified due to access to new markets and reduced return of spoiled product. However, despite its commercial success there are still many unknown factors associated with PEF processing of fruit and citrus juices and many conflicting reports in the literature. This literature review, therefore, aims to provide a comprehensive overview of the current scientific knowledge of PEF effects on microbial, enzymatic, nutritional, and sensory quality and stability of orange juices.