Image analysis of structural changes in dough during baking

The bakery market is developing new technologies based on dough partial baking and the study of the changes that dough undergoes through the whole baking process could help in the selection of baking times. The aim of this work was to study the changes of dough structure and their relationship with dough temperature, mass loss and loaf height during baking by applying image analysis techniques. Results showed that during baking, bubble coalescence was presented, observing a maximum at the first stages of baking (<250 s). This phenomenon was associated with an increment in dough height without a significant change in dough centre temperature. Fractal dimension of texture of crumb, fractal dimension of contour of cells and crumb grain features were useful indicators of coalescence as well as to distinguish the baking time needed for crumb features remain invariable.     

响应面分析法对重组牛肉脯色泽的改善

采用响应面优化试验方法,研究重组碎牛肉工艺中腌制时间,色素添加量,蛋清添加量对其色泽的影响。以3个因素为变量,以感官评分作为响应值,通过响应面分析方法得到最佳的色泽工艺配比。结果表明:重组牛肉脯较好色泽条件为腌制时间6.22h、蛋清添加量2.92%、红曲红色素添加量0.025%。在此条件下,a*23.76,L*32.31,感官评分96.3021,拟合度良好。     

Measurement by MRI of storage changes in commercial chocolate confectionery products

Storage of chocolate confectionery products was monitored non-invasively by Magnetic Resonance Imaging. Using a Carr–Purcell–Meiboom–Gill–(CPMG) sequence, 20 echo images (first echo 5 ms, subsequent echo every 5 ms) were acquired with a 2 s repetition time in a total 8-min scan time. Images were processed to give spatial maps of the proton density (M₀) and the transverse relaxation times (T₂-values) within the samples. In every case the T₂-values were successfully used to follow the migration of lipids from the fillings into the chocolate. The MR images also provided spatial information on the lipid migration.     

巧克力中沙门氏菌检验能力验证的结果与分析

目的 参加由中国食品药品检定研究院负责实施的NIFDC-PT-135巧克力中沙门氏菌检验能力验证活动, 提高微生物实验室沙门氏菌的检验检测能力,对实验室进行质量控制。方法 按照NIFDC-PT-135《巧克力中沙门氏菌检验作业指导书》和GB 4789.10-2016《食品安全国家标准 食品微生物学检验 沙门氏菌检验》条目要求对3件样品进行检验, 利用沙门氏菌生化鉴定盒和API20E生化鉴定试剂条进行鉴定。结果 样品编号为CODE: 0024的样品未检出沙门氏菌, 编号为CODE: 0754的样品检出沙门氏菌, 编号为CODE: 0883的样品未检出沙门氏菌。结论 本次实验室的能力验证试验结果为“满意”, 通过参加沙门氏菌的能力验证, 促进检测技术水平的提升, 为以后的工作开展提供技术储备。     

巧克力中沙门氏菌能力验证结果与分析

目的 分析实验室对巧克力中沙门氏菌检测能力验证实验与结果。方法 依据GB 4789.4-2016《食品安全国家标准 食品微生物学检验 沙门氏菌检验》对巧克力样品进行沙门氏菌检测。参照能力验证计划参试指导书来进行测定和结果判断。结果 通过平板法结合生化鉴定实验结果可知, 编号CODE:384有可疑目标菌落检出沙门氏菌阳性菌, CODE:544、CODE:699的可疑目标菌落均未检出沙门氏菌阳性菌。结论 本次实验室对巧克力中沙门氏菌检测能力验证结果合格, 为提高相关微生物实验室的检测能力提供参考。     

2018年巧克力中沙门氏菌检测能力验证结果与分析

目的参加中国食品药品检定研究院组织的NIFDC-PT-135巧克力中沙门氏菌检验能力验证,提高实验室的检测技术能力与水平。方法按照盲样作业指导书的要求对样品进行前处理后,依据GB4789.4-2016《食品安全国家标准食品微生物学检验沙门氏菌检验》中的方法,对3份样品进行沙门氏菌的分离和血清学鉴定,对分离出的可疑菌落用全自动微生物鉴定系统进行鉴定。结果CODE0109样品中检出鼠伤寒沙门氏菌、CODE0143样品中检出肠沙门双相亚利桑那亚种(沙门氏菌Ⅲb),CODE0835样品中未检出沙门氏菌。本实验室顺利完成考核,测定结果与考核结果一致。结论本次能力验证检出的肠沙门双相亚利桑那亚种在沙门氏菌显色平板上出现蓝色菌落,而以往则为紫红色菌落,因此在检测中应引起重视。通过此次能力验证,本实验室的沙门氏菌检测技术水平得到了有效验证和提高。     

巧克力中镉的定量测定能力验证结果与分析

目的通过参加FAPAS 07300"巧克力中铅、镉测定"能力验证,提高实验室对食品中镉的检测能力。方法针对FAPAS 07300样品,设计合适的检测实验方案,采用微波消解法对样品进行前处理,采用石墨炉原子吸收光谱法(graphite furnace atomic absorption spectroscopy,GFAAS)和电感耦合等离子体质谱法(inductively coupled plasma massspectrometry,ICP-MS)进行检测,并通过多种质量控制措施对测定结果进行评价。结果 FAPAS 07300样品的镉含量测定结果为120μg/kg,Z值为-0.1。结论实验检测能力评价为满意,表明本实验室巧克力中镉的定量测定能力较好。     

巧克力中沙门氏菌检测能力验证结果与分析

目的 通过参加中国食品药品检定研究院组织的NIFDC-PT-135巧克力中沙门氏菌检验能力验证活动, 提高实验室沙门氏菌的检测能力, 增强实验室的竞争力。方法 按照GB 4789.10-2016《食品安全国家标准 食品微生物学检验 沙门氏菌检验》进行沙门氏菌的分离与血清学鉴定, 辅以VIDAS 30 全自动酶联免疫分析系统进行快速初筛, 并以VITEK 2 Compact自动微生物快速检测分析系统对分离出的可疑菌落进行生化鉴定。结果 样品编号为0148的检出鼠伤寒沙门氏菌, 0546的检出肠沙门菌双相亚利桑那亚种(沙门氏菌Ⅲb), 0676未检出沙门氏菌。结论 本次实验发现的肠沙门菌双相亚利桑那亚种在沙门氏菌属显色平板上出现蓝色菌落, 与以往判定的紫红色菌落有差异, 在检测中应当引起关注。     

Image analysis of microstructural changes in almond cotyledon as a result of processing

Release of oil from nuts due to damaged cellular structures can degrade the quality of products incorporating nuts. The aim of this study was to investigate the effects of different processing conditions on microstructure of almond tissue and to quantify these changes using image processing. Spinning disk confocal fluorescence microscopy was used for imaging changes in microstructure of almonds as a function of different thermal processing of almonds. Multiple staining of Nile Red and Calcofluor White was applied to differentiate cell wall structures and oil bodies within individual almond cells without chemical fixation. An algorithm for image processing, included image preprocessing, segmentation, and determination of morphological features of segmented objects, was developed. Oil-roasting processes (140 °C and 150 °C) were found to have a significant impact on microstructure of almonds when compared to the hot air-roasting and blanching processes. Oil-roasted almond at 150 °C had a greater cellular damage due to cell wall and membrane rupture. These changes in microstructure of almonds would make them slightly more susceptible to release oil during storage. The image analysis presented allows quantitative evaluation for the effect of different processing on almond microstructure.     

Measurement of the geometrical features and surface color of rapeseeds using digital image analysis

Digital image analysis was applied to determine the geometrical features and color of rape seeds surface, and to discriminate some impurities, that are difficult to separate in the cleaning process. The paper notices on methodological aspects, and the experiment described constitutes the first stage of studies on the possibility of applying digital image analysis to rapeseed quality estimation, so the results obtained should be treated as preliminary. The geometrical features of seeds and their color were analyzed using the LUCIA G ver. 4.8 software. It was found that variation in geometrical dimensions of seeds was much lower than in color of their surface, so minimum sample size utilized for color measurements should be larger. The surface color of seeds was feature that insufficiently differentiates seeds of different dimensions. Only small seeds were characterized by somewhat changed distribution of color on their surface. An analysis of color of rape and stickywilly seeds in RGB (red/green/blue) model showed distinct differences in value ranges, enabling to distinguish between these seeds. Surface color of mature, immature and broken seeds cannot be used to distinguish these fractions.     

卵磷脂在巧克力中的应用

<正> 巧克力的主要成分有可可粉、可可脂、糖、奶油、奶粉和香精,其中的可可粉、奶粉和糖,是以微小的固体颗粒形式分散于可可脂和奶油的油相中。制造优质巧克力的关键,就在于使这些互不相溶的组分很好地结合在一起,添加卵磷脂,再配以适当的精烁温度(通常为80～90℃),就能够炼制出具有独特香气和香味的巧克力。     

互补色在服装色彩设计中的应用分析

互补色在纯艺术领域的绘画中已有较多的探讨和应用,而在服装领域还没有比较具有针对性的理论指导。通过互补色在自然色彩中的表现和美学渊源,得出了互补色服装配色是一种天然的、满足人类大脑视觉平衡系统的色彩设计方法,并接着对互补色服装调和方法以及在品牌服装中的应用进行了分析和探讨,为互补色彩在服装设计中更好地被采用提供一定的理论基础。     

Explaining tolerance for bitterness in chocolate ice cream using solid chocolate preferences

Chocolate ice cream is commonly formulated with higher sugar levels than nonchocolate flavors to compensate for the inherent bitterness of cocoa. Bitterness, however, is an integral part of the complex flavor of chocolate. In light of the global obesity epidemic, many consumers and health professionals are concerned about the levels of added sugars in foods. Once a strategy for balancing undesirable bitterness and health concerns regarding added sugars has been developed, the task becomes determining whether that product will be acceptable to the consumer. Thus, the purpose of this research was to manipulate the bitterness of chocolate ice cream to examine how this influences consumer preferences. The main goal of this study was to estimate group rejection thresholds for bitterness in chocolate ice cream, and to see if solid chocolate preferences (dark vs. milk) generalized to ice cream. A food-safe bitter ingredient, sucrose octaacetate, was added to chocolate ice cream to alter bitterness without disturbing other the sensory qualities of the ice cream samples, including texture. Untrained chocolate ice cream consumers participated in a large-scale sensory test by indicating their preferences for blinded pairs of unspiked and spiked samples, where the spiked sample had increasing levels of the added bitterant. As anticipated, the group containing individuals who prefer milk chocolate had a much lower tolerance for bitterness in their chocolate ice cream compared with the group of individuals who prefer dark chocolate; indeed, the dark chocolate group tolerated almost twice as much added bitterant in the ice cream before indicating a significant preference for the unspiked (control) ice cream. This work demonstrates the successful application of the rejection threshold method to a complex dairy food. Estimating rejection thresholds could prove to be an effective tool for determining acceptable formulations or quality limits when considering attributes that become objectionable at high intensities.     

花样翻新的巧克力糖果

"巧克力糖果已经显示出了强劲的增长势头,与上年同期(2006年7月至2007年6月)相比增长了26%,在2008年上半年也增长了25%。")     

响应面试验优化黄豆酱工艺条件及其色泽质构分析

以黄豆、小麦面粉为原料,采用混合菌种发酵制备黄豆酱,利用Box-Behnken响应面试验优化其工艺条件,并对黄豆酱的色泽与质构进行测定和分析。结果表明,最佳发酵工艺条件为121 ℃蒸煮黄豆16 min,湿黄豆与面粉质量比10∶3,发酵温度36 ℃。在此优化条件下,黄豆酱还原糖、氨基酸态氮含量分别为10.96%、0.76 g/100 g。在121 ℃条件下,随黄豆蒸煮时间在5～14 min、湿黄豆与蒸熟的面粉质量比在10∶1～10∶5及发酵温度在25～45 ℃范围变化,黄豆酱L*值及b*值逐渐下降,a*值逐渐上升,其色泽均匀,有光泽,逐渐加深最终为红棕色;黄豆酱的硬度与咀嚼性减弱,黏着性增强,其组织状态良好,质地细腻,黏稠适度,软硬适当,具有很好的咀嚼感。     

巧克力牛奶的研制

重点研究了不同产地和品牌的可可粉对产品口感的影响,以及不同的稳定剂对巧克力牛奶稳定性的影响。结果表明,选用DELFI可可粉制作巧克力牛奶脂香浓郁,口感最好,其用量为1.0%和1.25%的巧克力牛奶口感纯正。但从成本角度考虑,本实验选用1.0%的可可粉用量。该产品的稳定性需采用复配稳定剂,复配稳定剂最佳组合为卡拉胶0.015%,微晶纤维素0.13%,单甘酯0.1%。     

巧克力起霜的研究进展

本文根据当今研究进展,阐述了引起巧克力制品起霜的机理,即相态分离理论和多晶态转化理论,针对各种不同的起霜原由,提出不同的有效万法以延缓起霜现象的发生。