Efficacy of propionates and benzoates on the control of growth of Eurotium species in bakery products with near neutral pH

The effects of propionic acid, sodium propionate and benzoic acid on growth of various Eurotium isolates when added to a bakery product analogue were tested under various environmental conditions. The water activity of the products was adjusted to values in the range of 0.75–0.90 a_w, and storage temperatures were in the range of 15–30 °C. Propionates were added in concentrations ranging from 0.5 to 5 g kg^?1, while benzoic acid was added in the range of 0.25–1 g kg^?1. It was observed that 0.25 and 0.5 g kg^?1 concentrations sometimes enhanced isolate growth. When using sodium propionate, the highest concentration, 5 g kg^?1, completely inhibited growth under all conditions except for 0.85–0.90 a_w at 25–30 °C, while propionic acid completely prevented fungal spoilage regardless of the abiotic conditions assayed. On the other hand, benzoic acid at a given concentration had a wider effectiveness, thus used at 1 g kg^?1 concentration prevented growth under all conditions except for 0.90 a_w and 25–30 °C. It was concluded that trying to reduce the applied concentrations of these weak acid preservatives would be counterproductive and that, except for propionic acid, even at the higher permitted concentrations their use is not suitable for these near neutral pH products when their water activity is high (0.90 a_w). Copyright © 2004 Society of Chemical Industry     

散装酱卤鸭肉制品中特定腐败菌的确定

目的确定散装酱卤鸭肉制品的特定腐败菌(special spoilage organisms,SSO)。方法研究产品在4℃、25℃贮藏时的腐败特性,并对理化指标、感官指标和微生物指标进行相关性分析。结果散装酱卤鸭肉制品在25℃贮藏时,乳酸菌(1actic acid bacteria,LAB)、肠杆菌科、葡萄球菌属与挥发性盐基氮(total volatile basic nitrogen,TVB-N)、感官极显著相关(P0.01),最小腐败量(minimum spoilage,Ns)是7.09 1g(CFU/g);4℃贮藏时,嗜冷菌与硫代巴比妥酸反应物(thiobarbituric acid reactive substances,TBARS)、TVB-N和感官极显著相关(P0.01),Ns为6.71 1g(CFU/g)。不同的贮藏条件下SSO不同,嗜冷菌是散装酱卤鸭肉制品4℃贮藏的SSO,LAB、肠杆菌科和葡萄球菌属是该产品25℃贮藏的SSO。结论本研究可为有效建立该产品货架期预测模型、保证其品质安全性提供依据。     

Shelf life and safety concerns of bakery products--a review

Bakery products are an important part of a balanced diet and, today, a wide variety of such products can be found on supermarket shelves. This includes unsweetened goods (bread, rolls, buns, crumpets, muffins and bagels), sweet goods (pancakes, doughnuts, waffles and cookies) and filled goods (fruit and meat pies, sausage rolls, pastries, sandwiches, cream cakes, pizza and quiche). However, bakery products, like many processed foods, are subject to physical, chemical and microbiological spoilage. While physical and chemical spoilage limits the shelf life of low and intermediate moisture bakery products, microbiological spoilage by bacteria, yeast and molds is the concern in high moisture products i.e., products with a water activity (a(w)) > 0.85. Furthermore, several bakery products also have been implicated infoodborne illnesses involving Salmonella spp., Listeria monoctyogenes and Bacillus cereus, while Clostridium botulinum is a concern in high moisture bakery products packaged under modified atmospheres. This extensive review is divided into two parts. Part I focuses on the spoilage concerns of low, intermediate and high moisture bakery products while Part II focuses on the safety concerns of high moisture bakery products only. In both parts, traditional and novel methods of food preservation that can be used by the bakery industry to extend the shelf life and enhance the safety of products are discussed in detail.     

腌腊肉制品腐败变质的主要原因与控制措施

腌腊肉制品是中国传统肉制品的典型代表,其主要特点是易于加工生产、风味独特、可贮性佳。主要分析了腌腊肉制品的主要化学成分、生产原料、加工工艺、运输与贮藏等对其腐败变质的影响,同时提出有效的控制措施,为稳定产品的质量提供参考。     

乳品中腐败微生物检测及污染途径的研究进展

牛乳营养丰富,容易受到微生物的污染而引起腐败变质。该文从食品安全的角度出发,系统地介绍了乳品中主要的腐败微生物及其危害,概述了国内外乳品腐败微生物的检测方法,分析了其主要的污染途径,并提出了目前存在的问题和乳品中腐败微生物检测技术的发展方向。     

腌腊肉制品腐败变质的主要原因与控制措施

腌腊肉制品是中国传统肉制品的典型代表,其主要特点是易于加工生产、风味独特、可贮性佳。主要分析了腌腊肉制品的主要化学成分、生产原料、加工工艺、运输与贮藏等对其腐败变质的影响,同时提出有效的控制措施,为稳定产品的质量提供参考。     

非发酵豆制品主要腐败菌的分离鉴定

以非发酵性豆制品(豆腐丝、豆腐)为试验材料,从其腐败过程中分离纯化得到3株主要腐败细菌:df1、df2、df3,对其形态和菌落特征、生理生化特性进行了系统的研究,并进行了分类鉴定.结果表明引发非发酵性豆制品腐败变质的3株主要细菌为成团肠杆菌(E.agglomerans)、短小芽孢杆菌(Bacillus pumilus)和巨大芽孢杆菌(Bacillus megaterium).     

Use of a MS-electronic nose for prediction of early fungal spoilage of bakery products

A MS-based electronic nose was used to detect fungal spoilage (measured as ergosterol concentration) in samples of bakery products. Bakery products were inoculated with different Eurotium, Aspergillus and Penicillium species, incubated in sealed vials and their headspace sampled after 2, 4 and 7 days. Once the headspace was sampled, ergosterol content was determined in each sample. Different electronic nose signals were recorded depending on incubation time. Both the e-nose signals and ergosterol levels were used to build models for prediction of ergosterol content using e-nose measurements. Accuracy on prediction of those models was between 87 and 96%, except for samples inoculated with Penicillium corylophilum where the best predictions only reached 46%.     

水产品特定腐败菌群体感应及其植物源抑制剂研究进展

水产品的腐败过程主要由微生物活动引起。文章通过对水产品中的特定腐败菌、微生物的群体感应信号分子、群体感应抑制剂的来源与作用方式等进行阐述,提出当前植物源群体感应抑制剂存在的问题及解决措施。     

Aspergillus Flavus, Aspergillus Niger, and Penicillium Corylophilum Spoilage Prevention of Bakery Products by Means of Weak-Acid Preservatives

ABSTRACT: Apart from Eurotium species, Aspergillus and Penicillium isolates are common contaminants of bakery products. This paper deals with the use of weak-acid preservatives (potassium sorbate, calcium propionate, and sodium benzoate) to prevent spoilage by Aspergillus niger, A. flavus , and Penicillium corylophilum in analogs of a bakery product. A hurdle technology approach has been considered in which factors other than preservatives are pH and water activity. Potassium sorbate has been found to be the most effective in preventing fungal spoilage of this kind of products at the maximum concentration tested (0.3%). Suboptimal doses (0.03%) of all preservatives tested led to an enhancement of growth of Aspergillus and Penicillium isolates. The characteristics of the products involved must be carefully considered before making the decision of adding weak-acid preservatives; moreover, they must be added at the right concentrations. Furthermore, more research is needed on the use of alternative natural preservatives, such as essential oils.     

焙烤食品腐败霉菌的分离、鉴定与抑制研究

焙烤食品种类繁多、营养丰富,不仅容易氧化变质,更容易滋生霉菌,导致产品变质。本实验主要分为两部分:首先,分离、纯化几种发霉焙烤制品上的特征菌,通过形态观察,初步鉴定为青霉菌和曲霉菌;然后使用天然肉桂、丁香精油作为防腐剂,通过测定固相/气相抑菌圈和MIC来研究精油对霉菌的抑制作用。结果表明,肉桂、丁香精油对霉菌具有显著的抑制效果,可作为天然防腐剂应用于焙烤制品,达到抑菌、防腐和延长焙烤制品货架期的目的。      

脱氢醋酸钠在焙烤食品中的应用

脱氢醋酸钠是一种高效、广谱的食品防腐剂。本文简单介绍了脱氢醋酸钠的主要特性、生产方法、检测方法及其在焙烤食品中的应用。     

Concentrations and exposure estimates of deoxynivalenol in wheat products from Argentina

The aim of this work was to determine deoxynivalenol (DON) contamination in wheat-based food products in Argentina and to estimate DON exposure. The numbers of samples were determined according to a developed sampling plan. A total of 156 samples of different wheat products were randomly collected from food markets in Luján, Argentina, and analyzed for DON by gas chromatography. DON contamination ranged 7–271?ng?g^?1 for French bread, 5–149?ng?g^?1 for Vienna bread, 11–85?ng?g^?1 for crackers, 8–85?ng?g^?1 for pizza, and was 79?ng?g^?1 for noodles. The maximum contribution to DON intake was 7% of the PMTDI for French bread; the minimum was less than 1% for noodles. Assuming all groups had eaten all sampled foods and summing all groups’ intake contribution, the highest estimate DON exposure would only be <14% (for the 18–24-year old men group) of the DON daily dietary intake.     

重组海带面产品中腐败微生物的分离纯化及种类鉴定

以新型重组海带面产品为研究对象,对其贮藏过程中的腐败微生物进行了分离、纯化,并通过菌落形态观察、生理生化初步鉴别、VITEK微生物全自动系统分析对其种类进行了鉴定。结果表明,导致重组海带面产品腐败的微生物为产芽孢菌,分离到的6株菌分别为：短芽孢杆菌（Brevibacillus choshinensis）、枝芽孢杆菌（Virgibacillus proomii）、溶淀粉芽孢杆菌（Paenibacillus amylolyticus）、环状芽孢杆菌（Bacillus circulans）、凝结芽孢杆菌（Bacillus coagulans）和缓慢芽孢杆菌（Bacillus lentus）。     

基于扫描电镜观察研究真菌孢子检测对稻谷霉变判别

提出一种稻谷霉变判定方法——真菌孢子计数法。本研究借助扫描电镜观察方法,从微观角度对稻谷霉变判别进行研究,建立稻谷霉变与真菌孢子计数检测结果之间的关系,为稻谷霉变快速检测提供判定依据。对实仓采集稻谷样品进行真菌孢子检测,选取真菌孢子检出水平分别在0~5.0×10~4、1.0~5.0×10~5、1.0~5.0×10~6个/g稻谷样品,在每个检出水平中随机选取稻谷籽粒,对其稻壳、糙米以及精米进行扫描电镜观察。观察结果表明,糙米表面真菌孢子菌丝分布密度与原粮真菌孢子检出水平呈正相关,孢子数在0~5.0×10~4个/g水平时,稻壳和米表面几乎无法找到真菌孢子及菌丝,1.0~5.0×10~5个/g水平时,稻壳和糙米的胚乳及胚部零星分布真菌孢子和菌丝,而在1.0~5.0×10~6个/g水平时,稻壳和糙米籽粒表面真菌孢子和菌丝分布密集,分生孢子梗特征结构清晰可见。经过机械砻谷碾磨加工后得到一级大米,去除胚芽后裸露的胚部淀粉颗粒,受霉菌生长程度影响,粒径大小存在明显差异。真菌孢子检出在1.0~5.0×10~5个/g水平时,稻谷籽粒可判定为已经开始霉变。     

Effect of radiofrequency heating on acrylamide formation in bakery products

This work was addressed to study the influence of radiofrequency (RF) heating on acrylamide (AA) formation in bakery products. To this purpose, leavened cakes and short dough biscuits were baked to a final moisture of 3.5 and 3.0%, respectively, by means of conventional convection heating or different combinations of conventional and RF heating. Results showed that, with respect to the baking process entirely carried out in an air-circulating oven, the RF-assisted baking process, i.e. the application of RF heating in the last stages of the baking process, resulted to be a promising strategy to keep low the AA levels in the bakery products. In particular, the best results were obtained for products which were moved from the hot-air baking to the RF heating when their residual moisture was still fairly high (around 10%). Results also suggested that, when very low values of residual moisture are required, this technological intervention is more suitable to thin bakery products, such as biscuits, than to thick products, such as leavened cakes, because of excessive browning in the internal portion as a consequence of the RF heating.     

食用香精在烘焙食品中的应用

烘焙工业一直被认为是中国的黄金工业,烘焙食品以其丰富的营养,色香味俱佳,不断影响着人们的一日三餐。随着人们饮食结构的调整和生活品质的提高,趋于携带方便化、品种丰富化、口味多样化的烘焙食品在预期阶段内仍保持着稳定的增长趋势。烘焙食品的加香,对整个烘焙食品有着举足轻重的作用,经常被用来不断创造出新口味而使产品风味多样化。品类繁多,造型变化多端的烘焙食品有其各自不同的生产工艺要求和特殊的操作方式,对香精的使用,既讲究方法、技巧,又讲究加入时间。一方面,市场需求的不断变化和快速发展为食用香精的使用提供了广阔的市场空间,另一方面也为食用香精在烘焙食品中的应用研究提出了新的研究课题,同时也给食用香精的生产企业提供了新的机遇。     

Fiber from fruit pomace: A review of applications in cereal-based products

Fruit pomace is a by-product of the fruit processing industry composed of cell wall compounds, stems, and seeds of the fruit; after washing, drying, and milling, a material high in fiber and bioactive compounds is obtained. In bakery products, dried fruit pomace can be added to replace flour, sugar, or fat and thus reduce energy load while enhancing fiber and antioxidant contents. The high fiber content of fruit pomace, however, results in techno-functional interactions that affect physicochemical and sensory properties. In this article, different sources of fruit pomace are discussed along with their application in bread, brittle and soft bakery products, and extrudates.