Effects of rice bran fermented with Lactobacillus plantarum on palatability,volatile profiles,and antioxidant activity of brown rice noodles

Brown rice noodles (RN) are typical whole-grain products with health benefits. This study investigated the effects of rice bran fermented with Lactobacillus plantarum on palatability, volatile profiles, and antioxidant activity of brown RN. Three kinds of RN, including RN, brown RN (BRN), and bran fermented RN (BFRN), were involved in this study. The results indicated that bran fermentation reduced the cooking loss of BFRN and improved the elongation and the sensory attributes of brown RN. After fermentation, aldehydes were significantly decreased while alcohols increased, and more pleasant flavours were shown in BFRN. Fermentation increased the content of free phenolics and decreased the content of bound phenolics. Among the four major phenolics detected in this study, ferulic acid was the most abundant one in all three RN samples. The DPPH radical scavenging activity and the ferric reducing antioxidant power of free phenolics in BFRN increased significantly compared to BRN. This study proved that rice bran fermentation is an effective approach to improve palatability, enrich the flavour as well as enhance the antioxidant activity of brown RN, which may facilitate the development of processing technology for brown RN.     

Effects of non-thermal plasma treating wheat kernel on the physicochemical properties of wheat flour and the quality of fresh wet noodles

The effects of non-thermal plasma (NTP) on the physicochemical properties of wheat flour and the quality of fresh wet noodles ( FWN) were investigated. The results showed that NTP effectively decreased the total plate count (TPC), yeast and mould count (YMC) and Bacillus spp. in wheat flour. Wet gluten contents and the stability time reached the maximum when treated for 20 s. The viscosity of starch increased significantly after treatment due to the increased of damaged starch. The contents of secondary structure were altered to some extent, which was because that the ordered network structure of gluten protein broken. Furthermore, compared with the control, texture properties of FWN were enhanced significantly at 20 s, and the darkening rate of FWN was greatly inhibited due to the low polyphenol oxidase (PPO) activity. Consequently, the most suitable treatment was 500 W for 20 s, providing a basis for the application of NTP in flour products.     

Effects of ultrasound-assisted resting on the qualities of whole wheat dough sheets and noodles

The effects of resting under ultrasonic treatment on the properties of whole wheat dough sheets and noodles were investigated. Compared with the control group, the resting time to reach the maximum breaking force and extensibility of whole wheat dough sheets treated with ultrasound was shortened by 20 min. The proportion of strongly bound water (T₂₁) decreased, while the proportion of weakly bound water (T₂₂) increased during resting, and the ultrasonic treatment could accelerate this moisture redistribution in the dough. The extent of the increase in gluten macropolymer and the decrease in –SH content of ultrasound-treated wheat dough was higher than that of the control one during the initial 5–15 min resting, which could be related to the improvement of whole wheat dough extensibility. Whole wheat noodles showed a better breaking distance for 10 min of ultrasonic-assisted resting. Ultrasonic treatment could be used to reduce the resting time of whole wheat dough sheets and improve the texture properties of noodles.     

薯类粉条中与淀粉相关的结构性质研究

为了解薯类淀粉粉条结构特点,选取3种木薯淀粉(SC9、SC205、LMC),3种淮山淀粉(GY2、SFY、MPY)和1种红薯淀粉(XSSP)制成的粉条为研究对象,对其色泽、微观样貌、结晶结构进行测定和比较。结果表明,各粉条的色泽、微观样貌、结晶结构差异显著。星树红薯粉条色泽最好,而双峰淮山粉条色泽较暗。淮山粉条和红薯粉条存在部分还未完全糊化的淀粉颗粒,呈现出清晰的团粒结构,木薯粉条的糊化程度最高,淀粉的团粒结构已基本消失,SC9木薯粉条可以看到均匀完整的网络结构。粉条的结晶结构均遭到破坏,不同品种薯类粉条的有序结构与无序结构比例有明显差异。     

山药复合营养面条加工工艺研究

以新鲜山药泥、小麦粉为主要原料,牛肉、胡萝卜、脱脂纯牛奶和食盐为辅料,制备一款营养丰富、无添加剂的新型山药复合营养面条。通过单因素试验、正交试验和感官评价,筛选山药复合营养面条配方;通过物性指标、微观结构确定山药复合营养面条的最佳配方为:山药泥35%、牛肉∶胡萝卜质量比为1∶1、脱脂纯牛奶3%和食盐2.5%。     

Softness,elasticity, and smoothness characteristics of cooked udon noodles based on texture analysis

Objective evaluation methods for the elasticity, smoothness, and softness of cooked udon noodles were established on the basis of texture analysis. Noodles with different diameters and amylose contents were prepared to verify the reliability of the proposed evaluation methods. Results revealed that the elasticity of udon noodles could be examined by using the method that involved rinsing cooked noodles with 10°C cold water for 30 s and stretching a single strand of cooked noodle at 3 mm/s with an A/KIE probe until broken. The stiffness of the sample at 3.5 mm could be determined to indicate the elasticity caused by the size of dried udon noodles. The softness and smoothness of cooked udon noodles could be examined when cooled and drained for 30 s by using an heavy duty platform/pasta firmness/stickiness rig probe. The elasticity of cooked udon noodles increased as their diameter increased, and their smoothness and softness significantly increased as the amylose content decreased (p < .05). Texture analysis could be used to quickly and accurately indicate the elasticity, softness, and smoothness of cooked udon noodles. The texture characteristics of udon noodles were related to their formulation, processing, and size. Establishing an adaptability evaluation method for the quality of udon noodles is a prerequisite for optimizing processing technologies and developing new products. Thus far, limited research has focused on objective methods for evaluating the texture of cooked udon noodles. This work developed valuable instrumental methods for examining the elasticity, softness, and smoothness of cooked udon noodles and provided noodle manufacturers a tool for selecting udon noodle formulations and processing technology based on texture analysis.     

臭氧水对鲜湿面表面金黄色葡萄球菌的杀菌效果及其储藏安全控制研究

目的研究臭氧水对鲜湿面中金黄色葡萄球菌的杀菌作用,及天然抑菌剂对鲜湿面储藏过程中金黄色葡萄球菌的抑制效果。方法臭氧水浓度为0～20 mg/mL,处理温度为20-60℃,处理时间为0～20 min,分析不同条件下臭氧水对鲜湿面表面金黄色葡萄球菌的杀菌效果,后结合ε-聚赖氨酸的添加量范围为0%～0.03%储藏,研究抑菌剂对鲜湿面中金黄色葡萄球菌的抑制效果。结果臭氧水浓度为20 mg/mL,处理温度为60℃,处理时间为15 min时,能对金黄色葡萄球菌产生良好的杀菌效果,该条件下预处理能降低鲜湿面表面的金黄色葡萄球菌至4.3 lgCFU/g,ε-聚赖氨酸的添加量为0.03%时对金黄色葡萄球菌的抑制效果最好。结论降低鲜湿面表面金黄色葡萄球菌的起始值和储藏中添加抑菌剂结合冷链条件能有效的控制金黄色葡萄球菌的数量,在鲜湿面加工业中对金黄色葡萄球菌的控制具有一定的指导意义。     

不同马铃薯品种用于加工面条的适宜性

由于马铃薯品种繁多,不同原料品质会影响马铃薯面条的品质,为研究不同马铃薯品种加工面条的适宜性,指导马铃薯产业选择加工种植品种。试验采用最大-最小归一化处理方法将马铃薯面团和马铃薯面条的各个品质指标转化为一维的综合评价指标,分别与40个马铃薯原料品种的品质指标(淀粉、维C、可溶性蛋白、还原糖、粗纤维、钾、灰分、干物质、游离氨基酸、硬度、弹性、内聚性、咀嚼性、胶黏性、回复性)进行拟合并建立回归模型,采用聚类方法,将40个马铃薯品种按照加工适宜性分为三类。结果表明,建立的马铃薯面团综合品质评价模型决定系数R^2=0.911,调整后决定系数R^2=0.904,随机误差估计值=123.113;马铃薯面条综合评价模型决定系数R^2=0.973,调整后决定系数R2=0.971,随机误差估计值=432.226;利用K-means聚类算法将40个马铃薯品种按加工适宜性划分为最适宜、基本适宜和不适宜3类,其中最适宜加工的品种为05-44-1、克9、79(2)、C11、D17、C3、T3、庄3、会2、T4、L7、黑共12个品种,基本适宜品种为L0524-2、冀8、T2、F5、红、郑7、S3-28、中901、S4-32、中13、T5、冀12、甘农5、晋18、F6、T18、78共17个。该研究得到的综合品质评价模型拟合度较高,误差较小,模型效果可靠,可用于实际马铃薯面条的品质评价;K-means聚类结果与实际应用情况相符,可为新疆地区筛选加工专用品种提供参考和借鉴。     

全麦粉添加量对干挂面挥发性成分的影响研究

采用顶空固相微萃取-气相色谱-质谱联用法研究3种不同全麦粉添加量(50%、75%和100%)干挂面和1种精白挂面样品的挥发性成分,共检测到85种挥发性成分,其中包括17种醛,34种烃,16种醇,7种酮,1种呋喃,7种酯,2种胺和1种酸。四种挂面均含有烃类、醛类、醇类、酮类、酯类和胺类化合物。精白挂面和三种全麦挂面中分别检测到44、53、52和50种挥发性成分,全麦挂面相比于精白挂面挥发性成分显著增加。在挥发性成分中醛类物质是最主要物质,相对含量达25%以上。己醛含量显著高于其他醛类物质。全麦粉添加量的增加对各种类挥发性成分构成影响不大,而对各挥发性成分的相对含量有较大影响。