Comparison of the Frying Performance of Olive Oil and Palm Superolein

Abstract: Deep‐fat frying is an important method of food preparation in which foods are immersed in hot oil. Repeated use of frying oils is a common practice, and in the presence of atmospheric oxygen it produces various undesirable reactions in used oils. Stable frying oils usually require low linolenic acid (LnA < 3%), increased oleic acid (OA > 40%), and decreased linoleic acid (LA < 50%). The aim of this study was to establish the behavior of palm superolein (PSO) (OA 45%; LA 12.5%; LnA 0.2%) and olive oil (OO) during repeated, discontinuous deep frying of French fries. The behavior of the oils under controlled heating conditions was also studied by maintaining all of the process variables the same as those in deep frying, except that there was no food in the oil. The PSO selected to be tested in this study may represent an alternative to OO as a frying medium. Although PSO presented a faster increase in some oxidation indices, such as free fatty acid and total polar compounds, for other indicators, PSO showed better behavior than OO (less formation of C8:0 and lower peroxide value). Practical Application: The super palm olein selected for use in this study can be suggested as a suitable replacement for olive oil for frying and cooking purposes because it provides higher oxidative stability besides the beneficial effects of olive oil on human health. In fact, several studies have indicated that palm oil exhibits similar frying performance to high‐oleic oils, with the advantages of greater availability in the market and a lower price.     

The Effect of Food Type (Fish Nuggets or French Fries) on Oil Blend Degradation during Repeated Frying

Abstract: Oil that is reused multiple times for deep frying goes through changes in chemical composition and physical characteristics, affecting the quality of the fried foods. In this study, the effect of the food type (fish nuggets or French fries) on the degradation of an oil blend during the deep‐fat frying of each food at 180°C during 12 days was determined, and the characteristics of the fried products were evaluated. The degradation of oil during repeated use was relatively faster when fish nuggets were fried than when French fries were fried, as higher values of total polar compounds were obtained. Practical Application: The results are useful for producers of French fries and fish nuggets, such as restaurants or fast foods sellers, providing them with practical guidelines within the permitted values established by the regulatory authorities. The studied foods have high economic importance and are different in their composition. Under the studied conditions, the tested oil blend may be used during 4 d (4 h per day) with a daily replenishment, without discarding the oil when frying fish nuggets, and must be discarded after 8 d when French fries are processed. This suggestion allows preparing safe fried foods for consumers.     

Aflatoxin M1 and ochratoxin A in raw bulk milk from French dairy herds

Mycotoxins in milk are a public health concern and have to be regularly monitored. A survey on the presence of aflatoxin M₁ (AFM₁) and ochratoxin A (OTA) in raw bulk milk was conducted in 2003 in the northwest of France, the main French milk-producing basin. Randomly selected farms (n = 132) were characterized by a diet based on corn silage and containing a large proportion of on-farm produced cereals, feeding sources that are frequently contaminated by mycotoxins. Farms were surveyed twice in winter and in summer. At each sampling time, a trained surveyor completed a questionnaire recording farm management procedures and production traits. The AFM₁ was found in 3 out of 264 samples but at levels (26 ng/L or less) that are below the European legislation limit of 50 ng/L. Traces of AFM₁ (less than 8 ng/L) were also found in 6 other samples. The OTA was detected in 3 samples also at low levels, 5 to 8 ng/L. Farms that tested positive to the presence of mycotoxins, 12 in total including 6 farms that had traces of AFM₁, differed from negative farms by a more extensive use of total mixed rations, 58 vs. 27%. In addition, the positive farms tended to have lower milk yields. Although the incidence of milk contamination with AFM₁ and OTA at the farm level was low during the period studied, production and management data from the surveyed farms suggest a link between feeding management practices and mycotoxin contamination.     

法国“时尚与面料博物馆”及展览研究

在法国,对时尚问题的研究与展示约有150年的历史,这段历史的主要传承者包括成立于1986年的时尚与面料博物馆,它是本文研究的主要对象。该博物馆诞生于法国文化民主化背景之下,拥有丰富的历史馆藏,其藏品管理工作十分专业与科学。该博物馆与时尚品牌有着深度合作,其举办的时尚展兼具学术性与市场效应,但因此也会引起争议。这些争议引导我们思考两个维度的问题:时尚与艺术的关系以及博物馆的职能。     

催化重整再生技术中烧焦的相互比较

对UOP和IFP再生技术进行分析和比较.从流程、设备、积炭含量、烧焦过程的系统压力、烧焦过程的温度、烧焦过程的循环气量等方面进行了比较.比较结果表明:UOP工艺工艺简单、维护费用低、能耗低,但其高温高水高氯的环境对于催化剂的寿命是不利的.而IFP工艺所采用的干冷循环对于催化剂的寿命的延长是有利的,且设备的材质要求也没有...     

Effective quality control of incoming potatoes as an acrylamide mitigation strategy for the French fries industry

The correlation between sugar levels in raw material (potatoes), brown colouring and formation of acrylamide in French fries was investigated. The objective was to identify incoming potatoes (raw material) with a high potential for acrylamide formation. Ten different potato varieties commonly used in the Western European French fries industry were stored at 8°C and samples were taken throughout the storage time. The current quality control used in the French fries industry for incoming potatoes is poorly correlated with acrylamide in the final product (r = 0.74). Changing the quality control parameter from colour to reducing sugars in raw material did not improve the correlation (r = 0.72). The best correlation was obtained with the Agtron colour measurement after blanching and a two-stage frying (r = ?0.88). It was concluded that alternative entrance control measurements could provide better mitigation of the acrylamide issue in French fries from the start of production. These alternatives, however, are less cost-effective and more difficult to implement.     

法国电力供应链管理经验的启示

对法国电力供应链管理工作的经验进行了分析和总结,并对我国电网企业的供应链管理工作提出了一些建议。     

浅谈法型厂的原料路线和节能改造

针对国内 70年代引进的法型合成氨厂目前状况提出扭亏为盈的关键措施 ;依据安庆、广州石化总厂改造经验 ,阐述以炼厂干气部分替代石脑油作为法型厂原料时的工艺路线确定以及合成氨装置中转化、脱碳和汽提工段的节能改造措施。     

Mercury distribution in fish organs and food regimes: Significant relationships from twelve species collected in French Guiana (Amazonian basin)

Within a multidisciplinary research programme set up in French Guiana (Amazonian basin), twelve fish species from six food regimes were collected from the upper part of the Maroni River in order to analyze mercury (Hg) distribution in six organs (gills, liver, kidneys, skeletal muscle, stomach, and intestine) and to look for a relationship between Hg organotropism and food regimes. As many studies have shown, mercury biomagnification leads to extremely marked differences in muscle accumulation levels: the average ratio between extreme concentrations measured in piscivorous and herbivorous species was almost 500. A first principal component analysis on primary Hg concentration variables showed that biomagnification had a marked effect, masking differences between Hg distribution in the organs according to fish species and their food regimes. In order to avoid this, we determined ratios between Hg concentrations measured in the different organs and in the skeletal muscle, considered as the reference tissue for biomagnification effects. A new principal component analysis using these normalized values, in conjunction with a Ward's hierarchical clustering method, revealed that there is a link between Hg organotropism and the food regimes, with comparatively high [Hg]gills/[Hg]muscle ratios for the herbivorous species; high [Hg]intestine-liver-kidneys/[Hg]muscle ratios for the benthivorous and periphytophagous species, and, in contrast, ratios of less than 1 in the different organs for the piscivorous and omnivorous species. Our determinations of methylmercury (MMHg) percentages in the food consumed by the fish (aquatic macrophytes, terrestrial material from the river banks, biofilms, benthic invertebrates, fish muscle tissues), according to the different food regimes (herbivorous, periphytophagous, benthivorous, omnivorous, carnivorous, piscivorous), showed that this criterion can account for the differences in Hg distribution in the fish organs. For instance, the periphytophagous and benthivorous fish species ingest biofilms and small benthic invertebrates with quite low MMHg burdens (18% and 35 to 52% of Hgtotal, respectively). The highest [Hg]organs/[Hg]muscle ratios were observed for the liver and kidneys, the two principal target organs for inorganic Hg in fish. On the other hand, the piscivorous species ingest a large amount of fish of varying size, with high MMHg percentages in their muscle tissue (nearly 80%); Hg organotropism is characterized by high MMHg concentrations in the skeletal muscle and comparatively low [Hg]organs/[Hg]muscle ratios.     

Effects of Processing Conditions on Qualities of Rice Fries

ABSTRACT Two rice flour mixtures, 2 extruding temperatures, and 2 insert sizes were used to develop rice fries. The extruded material was cut into pieces 7 to 8‐cm long, prefried in rice oil at 180°C for 20 s, and kept frozen until final frying for another 70 s. The rice fries were evaluated 5 min and 10 min after final frying for their lipid, moisture, and instrumental texture characteristics. Extruding temperature, rice cultivar, and insert size were significantly related to fat content, moisture, hardness, and fracturability values. A mixture consisting of 80:20 (waxy:long‐grain), and extruded at 70 °C using a 6 mm insert, 5 min after frying, gave a texture profile analysis value for hardness, cohesive‐ness, and gumminess values comparable to commercial potato French fries. The rice fries made by the process also had less than 50% fat than potato fries.