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991.
Thermo-rheological behaviour of chestnut flour doughs supplemented with kappa/iota-hybrid carrageenan (HC) (up to 2.0%, flour basis (f.b.)) and sodium chloride (1.8%, f.b.) was determined at both target (C1) and final (C5) mixing peaks. For this purpose, small amplitude oscillatory shear (0.01 to 100 Hz), creep–recovery (loading of 50 Pa for 60 s, 30 °C), temperature sweeps (from 30 up to 180 °C) and heating/cooling cycles (between 30 and 60 °C) were conducted on a controlled stress rheometer. Previously, the thermal-mixing behaviour at proposed mixing temperature (50 °C) was conducted on Mixolab® apparatus. Results showed that the dough stability (from 2.2 to 5.8 min) in mixing stage and starch heat resistance to dough processing were significantly improved at proposed mixing temperature, even in the absence of HC. No statistical differences in rheological properties were observed for doughs evaluated in C1; however, those analysed in C5 were significantly modified in the presence of HC, mainly in terms of viscous behaviour (from 52.1 × 106 to 39.1 × 106 Pa s). Creep–recovery data sets, successfully fitted using Burgers model, revealed that the elasticity (J r/J max from 73.3 to 87.6%) of doughs analysed in C5 improved with HC addition. Thermal tests showed that the starch transitions were significantly promoted and stabilized with HC addition.  相似文献   
992.
The main objective of this study was to configure the acquisition and analysis of low-field magnetic resonance imaging (MRI) to predict physico-chemical characteristics of Iberian loin, evaluating the use of different MRI sequences (spin echo, SE; gradient echo, GE; turbo 3D, T3D), computational texture feature methods (GLCM, NGLDM, GLRLM, GLCM + NGLDM + GLRLM), and data mining techniques (multiple linear regression, MLR; isotonic regression, IR). Moderate to very good correlation coefficients and low mean absolute error were found when applying MLR or IR on any method of computational texture features from MRI acquired with SE or GE. For T3D sequence, accurate results are only obtained by applying IR on GLCM or GLCM + NGLDM + GLRLM methods. Considering not only the accuracy of the methodology but also consumed time and required resources, the use of SE sequences for MRI acquisition, GLCM method for MRI texture analysis, and MLR could be indicated for prediction physico-chemical characteristics of loin.  相似文献   
993.
In this work, a performing LC method with evaporative light-scattering detector was described for the analysis of tartaric, malic, ascorbic, citric and succinic acids in fruit juices. The method was optimized and validated in comparison with LC-UV, in terms of accuracy, LODs, LOQs and precision. The successive application to ACE, orange, pear, peach, mulberry and apple juices allowed separation and quantitative determination of organic acids in about 20 min just diluting and filtering the sample before LC determination. In the analysed juices, citric, malic and ascorbic acids were always present, and in all the samples, citric acid was the prevailing acid followed by malic acid except for peach and apple juices where an opposite trend was found. Tartaric and succinic acids were detected at lower concentrations and more rarely, except for peach juices, all containing tartaric acid, and ACE and orange juices, all containing succinic acid.  相似文献   
994.
995.
996.
黑米黄酒工艺及产品稳定性研究   总被引:5,自引:0,他引:5  
以黑米为原料生产黑米黄酒,黑米色素提取以浓度为20%-30%(v/v)的乙醇或米酒为最佳萃取溶剂,分两次萃取;黑米色素溶液及加工的黑米酒系列产品在酸性条件下色泽较稳定,适量使用蔗糖、柠檬酸或抗坏血酸等护色剂可明显提高产品色泽的稳定性;加工黑米黄酒,黑米原料仅需15%-20%,其余可用白糯米代替。(孙悟)  相似文献   
997.
采用CO2超临界萃取法和60%酒精热浸提法提取丢糟中的酯类物质,气相色谱分析结果表明:①两种方法均未能提取丢糟中的乙酸乙酯;②CO2超临界萃取法能够提取丢糟中的乳酸乙酯、己酸乙酯、丁酸乙酯和戊酸乙酯,而酒精热浸提法只能提取出乳酸乙酯和戊酸乙酯,且后者乳酸乙酯的含量达275.9285mg/100g,远远超过了前者的11.8955mg/100g。因此,提取丢糟中主要酯类成分,CO2超临界萃取法优于60%(v/v)酒精热浸提法。  相似文献   
998.
高温α-淀粉酶产生菌的筛选及酶学性质研究   总被引:6,自引:0,他引:6  
从酒厂高温曲中筛选到一株产高温α-淀粉酶的野生茼株,经初步鉴定为链霉菌,命名为Streptomycessp.1109。在45℃条件下,该茵株固体发酵产酶活力达到169.13u/g。通过酶学性质研究,该酶反应最适温度为85℃,最适pH为6.5,具有较高的热稳定性。  相似文献   
999.
This research evaluated the functional potential of a fermented milk made with Streptococcus thermophilus, a probiotic (Bifidobacterium animalis subsp. lactis) and pomegranate juice. Ferric‐reducing antioxidant potential, Trolox equivalent antioxidant capacity, scavenging effect on 1,1‐diphenyl‐2‐picrylhydrazyl free radical, oxygen radical absorbance capacity and Folin–Ciocalteu assays were used to estimate antioxidant activity and phenolic content. Probiotic survival, release and absorption of polyphenols were evaluated using in vitro gastrointestinal digestion. The concentration of polyphenols increased during digestion from 608 mg to 1417  gallic acid equivalents (GAE) /L. About 14% of polyphenols were found on the dialysate portion. The beverage presented high viability of probiotics with high survival rate after digestion (above 7 log cfu/mL).  相似文献   
1000.
造成大曲不生衣的原因很多,主要是受气候、环境和工艺条件的制约,不能给有益微生物菌系提供一个最佳的生长条件。目前,全国大曲生衣率仅在20%~50%之间,使用大曲生衣复合菌及新工艺操作,可提高大曲生衣率及大曲质量。试验表明,用0.1%。的大曲生衣复合菌,可使大曲生衣率提高到90%以上。  相似文献   
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