Development of a food product profile for boiled and steamed sweetpotato in Uganda for effective breeding

This study sought to understand user preferences of raw, boiled and steamed sweetpotato, a staple food in Uganda. A sequential methodology involving state of knowledge review, gendered food mapping, processing diagnosis and consumer testing was used in Lira and Kamwenge districts. Preferred raw sweetpotato characteristics were large roots (≥ 3 cm diameter) with a sweet taste, smooth skin and hard texture, while mealiness, sweet taste and good sweetpotato smell were important attributes for boiled sweetpotato. Processors, mostly women, highlighted ease of peeling and sappiness of raw roots. There were gender differences in quality characteristic preferences and perceived importance. The released variety, NASPOT 8, had the highest overall liking in Kamwenge and was well liked in Lira. Penalty analysis of consumer data showed that sweetness and firmness were key drivers of overall liking. The results will support breeding programmes in meeting specific end-user product profiles, selection criteria and uptake of new varieties.     

From cassava to gari: mapping of quality characteristics and end-user preferences in Cameroon and Nigeria

User’s preferences of cassava and cassava products along the value chain are supported by specific root quality characteristics that can be linked to root traits. Therefore, providing an evidence base of user preferred characteristics along the value chain can help in the functional choice of cassava varieties. In this respect, the present paper presents the results from focus group discussions and individual interviews on user preferred quality characteristics of raw cassava roots and the derived product, gari, – one of the major cassava products in Sub-Saharan Africa – in major production and consumption areas of Cameroon and Nigeria. Choice of cassava varieties for farming is mainly determined by the multiple end uses of the roots, their agricultural yield and the processing determinants of roots that support their major high-quality characteristics: size, density, low water content, maturity, colour and safety. Processing of cassava roots into gari goes through different technological variants leading to a gari whose high-quality characteristics are dryness, colour, shiny/attractive appearance, uniform granules and taste. Eba, the major consumption form of gari in Cameroon and Nigeria, is mainly characterised by its textural properties: smoothness, firmness, stickiness, elasticity and mouldability. Recommendations are made, suggesting that breeding will have to start evaluating cassava clones for brightness/shininess, as well as textural properties such as mouldability and elasticity of cassava food products, for the purpose of supporting decision-making by breeders and the development of high-throughput selection methods of cassava varieties. Women are identified as important beneficiaries of such initiatives giving their disadvantaged position and their prominent role in cassava processing and marketing of gari.     

卷烟制丝和卷制过程中主要质量指标与消耗指标的关系及评价方法

通过统计3个卷烟牌号的卷制质量指标、烟丝质量指标和加工的消耗指标并作回归分析,发现卷烟吸阻、硬度、填充值和烟支密度的乘积互为正相关关系,卷烟空头率、端部落丝量和含末率互为正相关关系,影响单箱耗丝的因素包括烟丝碎丝率、填充值和含水率。提出了对烟丝质量、制丝线消耗和卷制消耗的评价方法。      

加工方式对鲍鱼蛋白质及品质特性的影响研究进展

2022年,全中国鲍鱼产量为22.82万t,其中福建鲍鱼产量最高,达到18.15万t,占全国总产量的79.54%。鲍鱼富含优质的蛋白质和所有的必需氨基酸,是多不饱和脂肪酸、维生素和矿物质的良好来源。鲍鱼产品的品质特性不仅与不同的加工方式有关,而且与其蛋白质的性质密切相关。因此,本文综述了鲍鱼营养价值、加工制品、蛋白质性质、品质特性的研究进展;阐明了不同加工方式下鲍鱼蛋白质和产品品质特性之间的联系,主要包括蛋白质结构、非共价相互作用的破坏、肌原纤维蛋白的变性、结缔组织溶解等方面,进而改变了鲍鱼肌肉质构特性、蛋白质消化率、结构轮廓等特性,旨在为高品质鲍鱼制品加工提供一定的理论依据。     

Applications of imaging systems for the assessment of quality characteristics of bread and other baked goods: A review

One of the most widely researched topics in the food industry is bread quality analysis. Different techniques have been developed to assess the quality characteristics of bakery products. However, in the last few decades, the advancement in sensor and computational technologies has increased the use of computer vision to analyze food quality (e.g., bakery products). Despite a large number of publications on the application of imaging methods in the bakery industry, comprehensive reviews detailing the use of conventional analytical techniques and imaging methods for the quality analysis of baked goods are limited. Therefore, this review aims to critically analyze the conventional methods and explore the potential of imaging techniques for the quality assessment of baked products. This review provides an in-depth assessment of the different conventional techniques used for the quality analysis of baked goods which include methods to record the physical characteristics of bread and analyze its quality, sensory-based methods, nutritional-based methods, and the use of dough rheological data for end-product quality prediction. Furthermore, an overview of the image processing stages is presented herein. We also discuss, comprehensively, the applications of imaging techniques for assessing the quality of bread and other baked goods. These applications include studying and predicting baked goods' quality characteristics (color, texture, size, and shape) and classifying them based on these features. The limitations of both conventional techniques (e.g., destructive, laborious, error-prone, and expensive) and imaging methods (e.g., illumination, humidity, and noise) and the future direction of the use of imaging methods for quality analysis of bakery products are discussed.     

稻谷热风与真空干燥特性及其加工品质的对比研究

比较稻谷热风与真空干燥特性及对其加工品质的影响,为有效改善稻谷加工品质提供依据。通过对初始水分为26.5%的稻谷进行热风和真空干燥试验,研究热风干燥和真空干燥对稻谷的干燥特性和其加工品质的影响。结果表明:干燥温度越高,稻谷的平均降水速率越大,且真空干燥平均最大降水速率大于热风干燥平均最大降水速率;热风干燥在干燥开始后的5～10min降水速率出现最大值,真空干燥在干燥开始后的5～15min降水速率出现最大值。随着干燥温度的升高,稻谷的爆腰率上升,出糙率和整精米率下降;相同的干燥温度下,真空干燥稻谷的加工品质优于热风干燥稻谷的,其中爆腰率最为明显。对于高水分稻谷采用真空干燥可以提高稻谷的加工品质。     

Microbiological quality of raw milk used for small-scale artisan cheese production in Vermont: Effect of farm characteristics and practices

This study 1) evaluated the overall milk quality and prevalence of 4 target pathogens (Listeria monocytogenes, Staphylococcus aureus, Salmonella spp., and Escherichia coli O157:H7) in raw milk used for small-scale artisan cheesemaking and 2) examined specific farm characteristics and practices and their effect on bacterial and somatic cell counts (SCC). Raw milk samples were collected weekly from 21 artisan cheese operations (6 organic) in the state of Vermont that manufactured raw-milk cheese from cow (12), goat (5), or sheep (4) milk during the summer of 2008. Individual samples were examined for standard plate counts (SPC), coliform counts (CC), and SCC. Samples were also screened for target pathogens both quantitatively and qualitatively by direct plating and PCR. Overall, 86% of samples had SPC <10,000 cfu/mL, with 42% <1,000 cfu/mL. Additionally, 68% of samples tested were within pasteurized milk standards for coliform bacteria under the United States’ Grade A Pasteurized Milk Ordinance at <10 cfu/mL. Log₁₀ SPC and CC did not differ significantly among species. Similarly, method of sample delivery (shipped or picked up), farm type (organic or conventional), and duration of milking (year-round or seasonal) did not have significant effects on farm aggregated mean log₁₀ SPC, CC, or SCC. Strong positive correlations were observed between herd size and mean log₁₀ SPC and between log₁₀ SPC and CC as well as SCC when data from all animal species were combined. Although SCC for cow milk were significantly lower than those for goat and sheep milk, 98, 71, and 92% of cow, sheep, and goat milk samples, respectively, were within the compliance limits of the United States’ Grade A Pasteurized Milk Ordinance for SCC. Fourteen of the 21 farms (67%) were positive for Staph. aureus, detected in 38% of samples at an average level of 20 cfu/mL. Neither L. monocytogenes, E. coli O157:H7, or Salmonella spp. were detected or recovered from any of the 101 samples tested. Our results indicate that the majority of raw milk produced for small-scale artisan cheesemaking was of high microbiological quality with no detectable target pathogens despite the repeat sampling of farms. These data will help to inform risk assessments that evaluate the microbiological safety of artisan and farmstead cheeses, particularly those manufactured from raw milk.     

6种中非不同紫芽茶品质特性及其抗氧化活性研究

目的 比较中国与非洲肯尼亚不同紫芽茶品质特性及抗氧化能力。方法 对来自中非的6种紫芽茶进行感官审评,并比较其生化成分含量,通过测定1,1-二苯基-2-三硝基苯肼自由基(1,1-diphenyl-2-picrylhydrazyl radical,DPPH·)、2,2’-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐阳离子自由基[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt cationic radical, ABTS+·]的清除率和总抗氧化能力,评价6种不同紫芽茶体外抗氧化活性,并分析体外抗氧化活性与生化成分间的相关性。结果 感官审评结果表明,6种茶样的感官品质综合得分由高到低的顺序为:赤道富硒紫毫>紫娟绿茶>紫娟白茶>紫娟红茶>赤道富硒紫茶一级>赤道富硒紫茶二级。生化成分分析表明,以云南‘紫娟’品种为原料加工成的紫芽茶随着茶叶发酵程度的加深,儿茶素、茶多酚和花青素含量都显著降低,水浸出物含量逐渐增加,其中,紫娟绿茶的花青素和儿茶素总量最高。不同原料等级制成的3种赤...     

基于结构特性分析工艺对速食面叶复水性及品质的影响

目的 探究和面、压延和干燥过程中速食面叶结构特性的变化,分析对其复水特性及品质的影响。方法 利用低场核磁、傅里叶红外光谱仪、扫描电镜对速食面叶加工过程中水分分布、蛋白质二级结构、微观结构、面筋网络结构进行分析,研究不同工艺对面叶复水特性及品质的影响。结果 和面、压延过程中,速食面叶水分主要以T₂₁、T₂₂、T₂₃形式存在,且T₂₂占比在80%左右。加水量的增加和压延的进行,结合水比例上升,自由水比例下降,面叶持水能力增强。加水量38%、压延5次时,面叶中的二硫键和氢键含量最高,游离巯基和疏水相互作用含量最低,此时速食面叶有较好的复水性和品质;提高干燥温度,可以显著降低速食面叶湿基含水率,加大干燥速率,对蛋白质二级结构及孔隙率分布有显著影响。与60℃干燥相比,气流热风90℃只需干燥10 min,速食面叶的水分含量就能达到10%左右,气流热风干燥由于风速的影响,远比烘箱干燥速率快;随着干燥温度的升高,面叶内部孔隙率从4.17%增加到12.04%,复水时间从362 s缩短到273 s。结论 从加工过程中结...     

电子束辐照对小麦粉加工特性及馒头食用品质影响的研究

研究了不同剂量电子束辐照对小麦粉理化性质及加工品质的影响,并将其制成馒头,运用物性测试仪和感官评定方法分析了馒头的食用品质。结果显示:随着辐照剂量增加,小麦粉的降落数值及黏度特性显著下降,当辐照剂量达到5 kGy时,降落数值下降了56.2%,峰值黏度下降至42.7%,回生值下降至35.2%,而吸水量略有提高;面团的最大拉伸阻力逐渐降低,降幅随着辐照剂量的增大而增大,延伸度却逐渐增加,拉伸曲线面积则先增后减;物性测试仪测定结果表明,剂量在1.75 kGy以下时,辐照对馒头的黏附性影响较小,但达到2.75 kGy以上时,馒头的黏附性迅速增大,达到对照样品3倍以上;感官评定结果表明,当小麦所受辐照剂量达到5 kGy时,由其所制作的馒头感官评分低于60分,表明已不宜食用。     

即烹扇贝冷冻预制菜的质构特性及营养品质评价分析

目的 探讨即烹扇贝冷冻预制菜的质构特性和营养价值。方法 采用不同熟化方式对3种扇贝冷冻预制菜(蒸蒜蓉扇贝、香煎扇贝、烤扇贝)进行处理, 分析熟化后的质构、色差、微观结构、基本营养成分、氨基酸及脂肪酸组成与生扇贝及煮扇贝的差异, 采用相关性分析及主成分分析综合评价扇贝预制菜品质。结果 扇贝冷冻预制菜熟化后硬度、弹性和咀嚼性均显著性增加, 但蒸蒜蓉扇贝和烤扇贝的质构指标均低于煮扇贝和香煎扇贝, 后者肌肉纤维排列更紧密;香煎扇贝、烤扇贝和蒸蒜蓉扇贝的白度值均显著低于煮扇贝和生扇贝; 熟化后扇贝均具有高蛋白低脂肪的特点, 蛋白质含量为20.68~29.79 g/100 g, 粗脂肪含量为0.50~2.26 g/100 g; 氨基酸组成合理, 脂肪酸组成丰富, 必需氨基酸含量在22.05~31.07 g/100g, 烤扇贝具有较高的二十碳五烯酸和二十二碳六烯酸含量; 主成分分析营养价值由高到低为香煎扇贝>烤扇贝>蒜蓉扇贝>煮扇贝>生扇贝。结论 即烹扇贝冷冻预制菜熟化后营养全面, 香煎扇贝质构及营养价值综合评价较高, 本研究为后续开发扇贝产品提供了理论数据。     

基于新疆特色林果产品的质量安全追溯体系研究

为了保证新疆特色林果产品的持续优质化及可追溯性,通过新疆特色林果质量安全实时监控系统信息流程、追溯信息系统结构、前馈与反馈耦合的超前管理控制模型、质量安全追溯预警模型及其整体网络平台设计,解析了新疆特色林果质量安全追溯体系的组成及设计方法。本研究为新疆特色林果产品质量安全管理提供了有效手段,实践应用效果初步表明采用此理论研究成果建立完善新疆林果质量安全追溯体系可行,能为生产基地管理者、果品经营者、职能管理部门及消费者提供便捷可靠的信息咨询,并为相关农产品质量追溯提供借鉴。      

Carcass and ham quality characteristics of heavy pigs from different genetic groups intended for the production of dry-cured hams

Carcass and ham quality characteristics of pig populations divided by harvest weights — HW (130 and 160 kg) were evaluated to determine the effects of gender (barrows and gilts) and distinct genetic groups — purebred (DUDU) and crossbred Duroc (DULA, DUWI and DULL) as well as purebred Large White (WIWI) on the suitability for use in dry-cured ham production. At 130 kg, DUDU pigs yielded the highest fat thickness of the ham (P < 0.01) and an intramuscular fat content (IMF) of 3.15% in Semimembranosus muscle (SM). DUDU pigs also had a SM pH_u of 5.7. This genetic group met the specifications for dry-cured ham production. No differences could be found in meat quality characteristics between genetic groups harvested at 160 kg. However at this HW, gilts produced significantly (P < 0.05) heavier and leaner hams compared to barrows.     

Sensory evaluations of porcine longissimus dorsi muscle: Relationships with postmortem meat quality traits and muscle fiber characteristics

The objective of this study was to investigate sensory evaluations and their relationships with meat quality measurements and histochemical characteristics in both fresh and cooked pork. Based on the results, postmortem meat quality traits were closely related to almost all the evaluated sensory attributes. With regard to histochemical characteristics, muscle fiber area was related to both fresh- (r = 0.18, P < 0.05) and cooked-meat color (r = −0.24, P < 0.01) as well as abnormal flavor intensity (r = 0.25, P < 0.01), and muscle fiber composition was associated with fresh pork color and taste acceptability after cooking. There were no significant relationships (P > 0.05) between type IIa muscle fiber content and the evaluated sensory attributes; however, good meat sensory quality was partially explained by the percentage of type I fiber.     

不同保水性牦牛肉品质比较及肌原纤维蛋白凝胶特性分析

为探讨宰后不同保水性牦牛肉品质及肌原纤维蛋白凝胶特性变化,本实验利用聚类分析选取低汁液损失率组(n=6)(汁液损失率<1.5%)和高汁液损失率组(n=10)(汁液损失率≥1.5%),比较两组品质和蛋白凝胶特性。结果表明:保水性差的牦牛肉宰后p H较低,CIE L*较高,CIE a*较低,总蛋白和肌原纤维蛋白更易变性。牦牛肉肌原纤维蛋白凝胶硬度及保水性在p H7.0,离子强度0.6 mol/L,温度70℃下最优,且保水性好的肌肉凝胶硬度和保水性更佳。总之,水分可显著的改善牦牛肉品质及肉糜蛋白的凝胶特性。      

移栽期对烤烟产量、质量和光合特性的影响

2005年在黑龙江省宁安市进行了移栽期对烤烟的农艺性状、经济性状、化学成分、评吸结果、光合特性的影响研究,结果表明:宁安市地膜覆盖栽培烤烟的移栽期,以5月10日移栽较为适宜。这个时期移栽的烤烟,干物质积累较多,产量、产值较高。      

高质量发展背景下我国畜牧业提质增效制约因素分析及对策探讨

牛的心、肝、肺、肾等均属于牛的红脏,是牛主要的副产物之一。牛红脏具有较高的营养价值,含人体所需的各种营养成分包括蛋白质、脂质、维生素等。牛红脏中所提取的活性物质具有抗氧化、抗凝血、清除自由基、增强免疫力等保健作用。然而,牛红脏在药用和保健食品上仍未完全开发,整体加工利用率较低。由于牛红脏自身含有的腥味物质影响其加工利用,化学去腥、物理去腥及生物去腥等方法成为牛红脏加工产品的重要手段。该文对牛红脏结构特点、营养价值、活性成分及去腥方法以及产品开发现状进行概述,并对牛红脏新型产品开发及研究方向进行展望,以期为牛红脏在深入的开发提供理论依据。

     

Metabolomics in quality formation and characterisation of tea products: a review

Tea is one of the biggest categories of modern non-alcoholic beverages with health benefits. Through different processes, tea products are divided into six main types: green tea, yellow tea, white tea, oolong tea, black tea and dark tea. Metabolomics is helpful for the comprehensive, accurate and rapid determination of tea metabolites in different types of tea products and tea processing materials. It has been widely applied in studying the relationship of tea metabolites and its quality. Therefore, it is necessary to summarise the application of metabolomics in tea. In this review, we described and summarised (1) the main metabolites of six types of tea and their implications on tea quality with emphasis on the content differences in the main metabolites in different types of tea; (2) the research on optimising the key processing steps of six types of tea based on metabolomics and the discussion of various new strategies for effectively improving their quality and (3) the advanced approach to characterise and distinguish different grades of tea products via metabolomics. The current review offers guidance for the improvement of tea quality by metabolomics and its potential challenges.     

施氮量对烤烟经济性状、化学成分及香气质量的影响

以烤烟品种吉烟9号为材料,通过田间试验研究了不同施氮量对烤烟经济性状、化学成分和香气质量的影响。结果表明,施氮量60 kg/hm2的烟叶经济性状较好,糖碱比和氮碱比均较适宜,蛋白质含量较低,化学成分较为协调,棕色化产物类、类西柏烷类和类胡萝卜素类致香物质含量均高于其他处理,综合品质有较大的改善,表现为香气量较足、杂气较少、刺激性较低、余味舒适、烟气浓度大、燃烧性好、总得分最高。表明施氮量60 kg/hm2是该地区适宜的氮肥用量。