Chemical Detection of Mold in Processed Foods

Alternaria alternata, A. solani, Colletotrichum coccodes, Fusarium oxysporum, Geotrichum candidum, Rhizopus stolonifer and Drosophila flies were added to tomato and fruit purees and nectars at 0.1 - 10 mg (dry weight)/2g sample, hydrolyzed at 121°C in potassium hydroxide (KOH) and analyzed colorimetrically for glucosamine. Glucosamine varied with product, quantity of mycelium, hydrolysis time, KOH concentration, age (older cultures gave highest values), and mold species (R. stolonifer gave maximum and G. candidum, minimum values). When processed foods spiked with molds were analyzed, the mold concentration was linearly correlated to glucosamine but not to Howard mold count. Drosophila were barely detectable in hydrolyzed foods. Hydrolysis may be the critical step in this procedure.     

Effect of Fermentation Time on the Inositol Phosphates of Bread

Bread was made by an AACC procedure using whole wheat flour and 70%-extraction wheat flour. Five different fermentation times were applied. Six inositol phosphates and inorganic phosphate were separated, identified and quantified in the bread. It was found that phytate decreased and the inorganic phosphate increased, with the largest decrease in phytate occurring during first 30 min of fermentation. The content in intermediate inositol phosphates also changed and it was only after considering their phosphorus content that an overall phosphorus balance could be achieved.     

减少高温加工食品中丙烯酰胺含量的几种方法

原料中还原糖、天冬酰胺含量及加工温度是影响食品中丙烯酰胺形成的主要因素。减少原料中的还原糖或天冬酰胺含量及降低加工温度能显著降低食品中丙烯酰胺的含量。本文概述了几种减少高温加工食品中丙烯酰胺含量方法的研究进展。     

Acid Requirement for pH Modification of Processed Foods

A bench-top procedure was developed and tested for estimating the acid requirement for modifying the pH of low acid foods. Acid amounts needed to achieve desired equilibrium pH in finished products depended on total solids, protein and ash contents of foods, and on buffering capacities of acidulants and foods. Acid requirements to modify pH were calculated from titration curves. Specified equilibrium pH values were achieved within 0.08 pH unit. Effective gluconic acid diffusion (D_eff) into a buffered model food was 8.3 × 10^?10±1.5 × 10^?10 m²sec-¹.     

磷酸盐在肉制品加工中作用及替代物研究进展

综述磷酸盐在肉制品加工中的作用及其替代品的研究进展.由于磷酸盐具有潜在的有害作用,磷酸盐替代品的开发引起广发的兴趣.通过这些替代物的使用实现既能降低肉制品中磷酸盐的使用量、又能改善肉制品品质的目标.     

Effect of Milling Extraction on the Inositol Phosphates of Wheat Flour and Bread

SRW wheat was experimentally milled to 70%, 80%, 90% and 100% extraction flours, and “standard” bread was prepared from these flours. Six inositol phosphates and inorganic phosphate were found in all flours and breads. Inositol hexaphosphate, inorganic phosphate and total P increased with the degree of extraction. About 2/3 of the inositol hexaphosphate disappeared as a result of bread making, but an overall phosphate balance was possible only after taking into account the intermediate inositol phosphates. Commercial white bread and whole wheat bread were also analyzed for the entire spectrum of phosphates.     

Minimally Processed Functional Foods: Technological and Operational Pathways

This paper offers a concise review of technical and operational concepts underpinning commercialization of minimally processed functional foods (FFs), foods with fresh‐like qualities commanding premium prices. The growing number of permitted nutritional content/health claims, many of which relate to well‐being, coupled with emerging extraction and food processing technologies offers new exciting opportunities for small and medium size enterprises (SMEs) specializing in fresh produce to play an active role in the health market. Supporting SMEs, governments could benefit from savings in healthcare costs and value creation in the economy. Consumers could benefit from novel FF formats such as refrigerated RTE (ready‐to‐eat) meals, a variety of fresh‐like meat‐, fish‐, and egg‐based products, fresh‐cut fruits and vegetables, cereal‐based fermented foods and beverages. To preserve these valuable commodities, mild biological (enzymatic treatment, fermentation and, bio‐preservation) and engineering solutions are needed. The latter include nonthermal techniques such as high‐pressure treatment, cook‐chill, sous‐vide, mirco‐encapsulation, vacuum impregnation and others. “De‐constructive” culinary techniques such as 3D food printing and molecular gastronomy as well as developments in nutrigenomics and digital technologies facilitate novel product formats, personalization and access to niche markets. In the operational sense, moving from nourishment to health improvement demands a shift from defensive market‐oriented to offensive market‐developing strategies including collaborative networks with research organizations.     

Processed Protein Foods Characterized by In Vitro Digestion Rates

In vitro tryptic digestion assays and determination of relative digestion rates of food proteins described previously were used to evaluate changes in the rate of digestion following processing technologies. If pH drop measurements are used, a simple mode for the determination of relative digestion rates is suggested based on the comparison with a single reference of the same protein source. The effect of processing technologies could be tested in vitro. Significant increase in the velocity of digestion was found on microwave treatment of lentil and raw soy bean as well as on acid treatment of commercial defatted soy meals. Increase in the in vitro digestion rates was reflected in decreased feed consumption per weight gain in pig feeding experiments.     

9种大豆制品中转基因成分定性PCR检测

本研究从豆粕、豆粉、豆腐等9种大豆产品中提取到高质量的DNA,在对内标准基因Lectin进行扩增的基础上,设计相应的特异性引物,建立了稳定的定性PCR反应体系,对35S启动子基因、外源目的基因Cp4-epsps基因进行了扩增,发现豆粕、豆奶粉、豆腐、豆皮、豆豉中含有转基因成分,而其它产品中未发现转基因成分存在.     

Colour Measurement and Analysis in Fresh and Processed Foods: A Review

Colour is an important quality attribute in the food and bioprocess industries, and it influences consumer’s choice and preferences. Food colour is governed by the chemical, biochemical, microbial and physical changes which occur during growth, maturation, postharvest handling and processing. Colour measurement of food products has been used as an indirect measure of other quality attributes such as flavour and contents of pigments because it is simpler, faster and correlates well with other physicochemical properties. This review discusses the techniques and procedures for the measurement and analysis of colour in food and other biomaterial materials. It focuses on the instrumental (objective) and visual (subjective) measurements for quantifying colour attributes and highlights the range of primary and derived objective colour indices used to characterise the maturity and quality of a wide range of food products and beverages. Different approaches applied to model food colour are described, including reaction mechanisms, response surface methodology and others based on probabilistic and non-isothermal kinetics. Colour is one of the most widely measured product quality attributes in postharvest handling and in the food processing research and industry. Apart from differences in instrumentation, colour measurements are often reported based on different colour indices even for the same product, making it difficult to compare results in the literature. There is a need for standardisation to improve the traceability and transferability of measurements. The correlation between colour and other sensory quality attributes is well established, but future prospects exist in the application of objective non-destructive colour measurement in predictive modelling of the nutritional quality of fresh and processed food products.     

Utilization of β-Cyclodextrin for Improved Flavor Retention in Thermally Processed Foods

ABSTRACT: Four flavorants were complexed individually with β-cyclodextrin, and the resulting inclusion complexes were used to flavor hard candy, fruit leathers, and angel food cake. Flavor retention during preparation using complexed and liquid flavor forms was assessed by instrumental analysis. Complexation of flavors in β-cyclodextrin markedly improved heat stability in some cases; the more severe the heat treatment experienced by the food, the greater the observed benefit; for example, 86-fold better retention of l-menthol in a hard candy. However, results of sensory evaluation were mixed, indicating that the benefits of enhanced flavor retention achieved through the use of flavor/cyclodextrin complexation could be mitigated by poor release from inclusion complexes during consumption.     

Lycopene Epoxides and Apo-Lycopenals Formed by Chemical Reactions and Autoxidation in Model Systems and Processed Foods

ABSTRACT:  To gain a better understanding of the reactions and the underlying mechanisms of the oxidative degradation of lycopene, the products formed by epoxidation with  m -chloroperbenzoic acid (MCPBA), oxidative cleavage with KMnO₄, and autoxidation in low-moisture and aqueous model systems, under light exposure, at ambient temperature were identified. The presence of oxidation products was also verified in processed products (tomato juice, tomato paste, tomato puree, guava juice, goiabada). A total of 8 lycopene epoxides and a cyclolycopene diol were formed by the reaction of lycopene with MCPBA and 6 apo-lycopenals were produced with KMnO₄. Some of these oxidation products were not detected in the model systems and in the foods analyzed, but the acid-catalyzed rearrangement product 2,6-cyclolycopene-1,5-diol and apo-12'-lycopenal were found in all model and food systems and lycopene-1,2-epoxide and 2,6-cyclolycopene-1,5-epoxide were found in the model systems and in all but 1 (goiabada) of the 5 foods analyzed. Other epoxides and apo-lycopenals were found in some systems. The inability to detect an intermediate product could be due to a fast turn over. Increased  Z -isomerization was also observed and  Z -isomers of the oxidation products were detected.     

超高静压下食品压致升温的预测及数学模型建立

为了弄清食品在超高静压下的压致升温情况,以便准确控制杀菌的加工工艺条件,本文测定了较小热损失条件下(利用聚四氟乙烯套筒模拟)食品及其成分的压致升温值并提出了预测某一食品压致升温值的方法,与实测值比较可知此方法能较好地预测其压致升温值;由热力学第一定律推导出一定压力和温度范围内某一食品的压致升温值主要取决于其初始温度和压力,并通过经验方程拟合食品的压致升温值,建立了食品压致升温值与压力和初始温度之间的关系。在100~400 MPa下温度25~55℃时较小热损失条件下对水、大豆油和橄榄油的压致升温值进行拟合,结果表明,对这三种物质拟合得到方程的回归系数依次分别为0.976、0.990和0.981,此外,将实测值和用方程拟合得到的预测值进行比较,相对误差均不超过5%,说明此方程的拟合效果较好。     

基于多重连接依赖探针扩增（MLPA）技术检测加工食品中过敏原成分

该研究基于多重连接探针扩增技术（Multiplex Ligation-dependent Probe Amplification,MLPA）同时检测开心果、巴西坚果、芹菜、麸质、夏威夷果、芝麻、榛子、大豆、花生、葵花籽、核桃、腰果、杏仁、芥末等14种植物源性的过敏原成分,针对ITS序列设计特异性杂交探针,样本核酸经95 ℃变性后,与探针进行特异性结合,经连接和PCR扩增反应得到不同大小的目标片段,通过毛细管电泳分析目标片段的有无来判断是否含有待测过敏原成分。利用混合探针体系检测单一模板只能扩增出单一扩增峰,表明探针具有高特异性,检测限结果表明,MLPA扩增最低可检出的DNA质量浓度为1 ng/μL。通过20份实际样本的检测,证明该研究基于MLPA建立的加工食品中过敏原成分的检测方法,具有特异性强,灵敏度高的特点,可以应用于食品安全监管工作。     

Natural Fermentation of Lentils: Influence of Time,Concentration and Temperature on the Kinetics of Hydrolysis of Inositol Phosphates

Lentil (Lens culinaris var vulgaris) flour was naturally fermented for 96 h at various conditions of concentration (79, 150 and 221 g litre⁻¹) and temperature (28°C, 35°C and 42°C). The content of total inositol phosphates (IP-total) and individual inositol phosphates (hexa- (IP₆), penta- (IP₅), tetra- (IP₄) and tri- (IP₃) phosphates) were analysed to establish the changes of these compounds during natural fermentation of lentils. The preparation of the lentil suspension brought about 16–27% reduction of the total inositol phosphates. At the end of 96 h of natural fermentation maximum IP loss (70–75%) was achieved for an experiment carried out at minimum concentration. For IP₆, the largest decrease was achieved at the highest temperature, the fermentation condition that also brought about the highest IP₅ content.     

A Rapid and Simple Method for the Determination of 2-Alkylcyclobutanones in Irradiated Meat and Processed Foods

A rapid and simple method has been developed for the determination of 2-alkylcyclobutanone, 2-dodecylcyclobutanone (DCB), and 2-tetradecylcyclobutanone (TCB) in irradiated meat and processed foods. The procedure consists of extraction with n-hexane, following defatting and cleanup with a silica gel mini-column before gas chromatograph–mass spectrometry analysis. The method was evaluated using samples of beef, pork, Parmesan cheese, fried chicken, hamburger, gyoza (Chinese dumplings), and gyudon (boiled beef and onion seasoned with soy sauce and sugar). The recoveries of spiked DCB were 67–88 %, and those of TCB were 70–86 %. Furthermore, the method could detect DCB and TCB from samples irradiated at 1.0 and 2.6 kGy at levels dependent on dose; DCB and TCB were not detected in any nonirradiated samples. The method did not require special equipment, such as Soxhlet extraction, accelerated solvent extraction, or supercritical fluid extraction, for sample preparation. Thus, this method would be useful for determining DCB and TCB levels in irradiated meat and processed foods.     

Determination of D-Amino Acids in Some Processed Foods and Effect of Racemization on In Vitro Digestibility of Casein

Several processed foods and controls were analyzed by gas chromatography for the presence of D-amino acids. The concentration of each of the D-amino acids detected in the processed foods was approximately the same as that in the controls except that D-aspartic acid was significantly higher in dark toast surface and extruded soy flour. In vitro digestibility of casein which was alkali-treated to cause racemization, but without lysinoalanine (LAL) formation, was essentially the same as that of racemized casein containing LAL, but was lower than that of nonracemized control casein.     

Use of Iodized Salt in Processed Foods in Select Countries Around the World and the Role of Food Processors

Executive Summary: The Micronutrient Initiative (MI) issued the Institute of Food Technologists (IFT) a project to assess the extent to which iodized salt is used in processed foods, as well as food processors’ level of knowledge on iodine nutrition. Iodine is an essential micronutrient required by the body that is found in a limited number of foods, thus many individuals require additional sources of iodine to meet their daily requirement. Without these additional sources, a range of disorders referred to as iodine deficiency disorders (IDD), including mental impairment, may become present, with over 2 billion people worldwide at risk due to insufficient iodine nutrition. IDD is especially damaging during the early stages of pregnancy and in early childhood. In their most severe form, IDD includes cretinism, stillbirth, and miscarriage, and increased infant mortality. Since 1994 the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF) have recommended universal salt iodization (USI) as a safe, cost‐effective, and sustainable strategy to ensure sufficient intake of iodine by all individuals. However, USI has in practice tended to focus only on table salt and not all salt destined for human consumption. Recent trends, particularly in industrialized countries, show that individuals are consuming the majority of their salt through processed foods, in which iodized salt is generally not used, rather than through iodized table salt. Additionally, recent initiatives to encourage reduced sodium consumption have prompted many consumers to reduce their intake of iodized table salt. While these trends in sodium consumption are more frequently observed in industrialized countries, they are expanding into many developing countries where iodine deficiency is also a concern. Thus countries which focus on iodization of table salt alone may not achieve optimal iodine nutrition of their population. This report provides an overview of the 2 Phases of this project. Phase I was to conduct an environmental scan/desk review of processed food consumption patterns in 39 countries selected by MI (see Table 1 ). Phase II was to conduct an electronic survey of food processors and detailed telephone interviews with a small sample of select company representatives from 16 countries (see Table 2 ). Per the scope of work, IFT conducted a desk review to determine the types and level of processed food consumption in the 39 countries of interest, as well as to identify suppliers of the major processed foods consumed and the use of salt as an ingredient in those products. Whenever possible, IFT also gathered information on the sodium content of widely consumed processed foods and the sources of salt currently used in these products; the types of processed foods and extent to which they are consumed by different socioeconomic groups; if iodized salt was used in processed foods; and whether or not there are policies in place to influence dietary salt reduction and how these efforts are implemented. For Phase II, IFT reached out to food company representatives to determine their use of iodized salt in processed food products; their sources of salt; their awareness of iodine nutrition and salt as a fortification vehicle; and their interest in learning more about salt iodization. For the purposes of this project, processed foods are considered to be all food products that have undergone a change of character or been altered from their original form.

Table 1–. Preselected countries (from MI) for Phase I of the iodized salt in processed foods project.

基于UPLC-QqQ-MS/MS同步检测热加工食品中典型晚期糖基化终末产物

建立超高效液相色谱-三重四极杆串联质谱法测定热加工食品中羧甲基赖氨酸（Nε-carboxymethyllysine,CML）和羧乙基赖氨酸（Nε-carboxyethyllysine,CEL）含量的同步检测方法。首先脱脂样品经硼氢化钠还原8 h,沉淀蛋白,酸水解后,经Oasis MCX固相萃取小柱净化和富集,以乙腈和含0.1%甲酸的1 mmol/L乙酸铵溶液为流动相梯度洗脱,采用ACQUITY UPLC HSS T3-C18色谱柱分离,多反应监测模式进行定性定量分析。CML和CEL在0.25～500 ng/mL范围内线性良好,相关系数高于0.999,方法检出限分别为8 ng/g和10 ng/g,定量限分别为36 ng/g和40 ng/g。平均回收率分别为96%～103%和94%～107%,相对标准偏差分别为1.48%～2.43%和1.23%～1.84%。利用该方法检测13 种市售热加工食品发现,婴儿肉松和婴儿饼干中CML和CEL含量显著高于烘焙食品和油炸食品（P＜0.05）。结果表明该方法快速、准确、高效,适用于热加工食品中CML和CEL的同步快速检测。