Improvement of accuracy for the determination of vitamin A in infant formula by isotope dilution-liquid chromatography/tandem mass spectrometry

Analysis of vitamin A in food has been an intricate subject due to its labile properties. In this study, an isotope dilution-liquid chromatography/mass spectrometric (ID-LC/MS) method was established as a candidate reference method for the accurate determination of vitamin A in infant formula. We found that the oxidative degradation of vitamin A in sample preparation processes is a key fact that hampers reliability of measurement results. Therefore, sample preparation processes were carefully designed to minimise oxidative degradation of vitamin A by preventing sample from exposure to air. Similar cautions were applied for the preparation of calibration solutions. Both within-day repeatability and among-day reproducibility tests of the ID-LC/MS method showed less than 1.0% of relative standard deviation, and the measurement uncertainty by this method is estimated to be less than 1.0%. The newly designed method showed greatly improved performance compared to methods reported in other literatures.     

内蒙古地区婴幼儿配方乳粉中高氯酸盐与氯酸盐膳食暴露风险评估

目的 了解内蒙古地区婴幼儿配方乳粉中高氯酸盐和氯酸盐的污染水平,评估婴幼儿高氯酸盐和氯酸盐的膳食摄入风险,为指导内蒙古地区婴幼儿健康膳食提供科学依据。方法 采集内蒙古地区市售各段位的婴幼儿配方乳粉539份,乳粉冲调用水（冲调乳粉时可能使用的饮用水）254份,采用超高效液相色谱-串联质谱（UPLC-MS/MS）法对婴幼儿配方乳粉、乳粉冲调用水中的高氯酸盐和氯酸盐含量进行检测。以2015年中国婴幼儿食品消费量调查数据中内蒙古地区婴幼儿的消费量数据为依据,采用简单分布评估和累积暴露评估方法计算内蒙古地区婴幼儿配方乳粉中高氯酸盐和氯酸盐的膳食摄入风险。结果 婴幼儿配方乳粉中高氯酸盐的总体检出率为92.39%(498/539),检测值在未检出～89.30μg/kg,平均值为14.45μg/kg,中位数为9.00μg/kg;氯酸盐的总体检出率为73.10%(394/539),检测值在未检出～1 061.00μg/kg,平均值为93.25μg/kg,中位数为45.50μg/kg。乳粉冲调用水中高氯酸盐的总体检出率为67.32%(171/254),检测值在未检出～26.59μg/L,平均值为1.25μ...     

上海市市售婴幼儿配方乳粉中氯丙醇酯和缩水甘油酯的监测及膳食暴露评估

目的 了解上海市市售婴幼儿配方乳粉中氯丙醇酯（MCPDE）和缩水甘油酯（GE）的污染水平,评估婴幼儿膳食暴露风险。方法 利用2020年上海市市售90件婴幼儿配方乳粉中MCPDE和GE的风险监测数据,结合婴幼儿膳食消费量数据,采用点评估法对婴幼儿经婴幼儿配方乳粉的3-MCPDE、2-MCPDE和GE进行膳食暴露评估。结果 上海市市售婴幼儿配方乳粉中3-MCPDE、2-MCPDE和GE的检出率分别为100%、100%和12.2%,含量平均值分别为0.084、0.021和0.005 mg/kg,最大值分别为0.231、0.034和0.031 mg/kg。上海市0~6月龄婴儿每日经婴幼儿配方乳粉摄入3-MCPDE的平均暴露量和P₉₅暴露量分别为1.262和2.166 μg/kg·BW,分别占3-MCPDE每日耐受摄入量（TDI,2 μg/kg·BW）的63.1%和108.3%。6~12、12~36月龄婴幼儿每日经婴幼儿配方乳粉摄入3-MCPDE的平均暴露量和P₉₅暴露量均低于TDI值。不同月龄组婴幼儿每日经婴幼儿配方乳粉摄入2-MCPDE的平均暴露量为0.118~0.319 μg/kg·BW。不同月龄组婴幼儿每日经婴幼儿配方乳粉摄入GE的平均暴露边界比（MOE）和P₉₅ MOE均大于10 000。结论 上海市0~36月龄婴幼儿每日经婴幼儿配方乳粉摄入3-MCPDE和GE的健康风险总体上处于可接受水平。但对于高食物消费量的0～6月龄婴儿,其通过婴幼儿配方乳粉暴露3-MCPDE的健康风险需引起关注。     

Maternal feeding practices during the first year and their impact on infants’ acceptance of complementary food

The introduction of weaning foods is a major transition in the development of infants’ eating behavior. Previous studies showed that greater variety at the beginning of the weaning period can later influence an infant’s acceptance of new foods. The aim of the present study was to describe maternal feeding practices in the first year (breastfeeding duration, age at the initiation of weaning, variety of new foods introduced) and to study whether they impacted infants’ later acceptance of new foods in a longitudinal survey of French children’s eating behavior.Mothers (n = 203) were asked to record each food offered to their infants from the beginning of the weaning period to the age of 15 months and to score the acceptance of each food for the first 4 presentations. The foods were clustered into categories (i.e. fruits, vegetables…). The link between individual characteristics (maternal age, education level, parity, caregiver during weaning and infant gender) and exclusive breastfeeding duration, age at the initiation of weaning, age at the introduction of each food category, number of new foods introduced from all categories and the infant’s acceptance of each food was studied. Finally, the link between feeding practices and infants’ acceptance of new foods was analyzed.Seventy-two percent of the infants were exclusively breastfed from birth for a median duration of 68 days. On average, the age at the initiation of weaning, 5 months, was in accordance with the current French recommendations. The number of new foods introduced was 13.4 per month on average and differed from one infant to another with no association with individual characteristics. The reactions to new foods were positive in 90% of the cases but differed according to food categories. In the early weaning period, fruits and vegetables were the least positively accepted foods; however, the average acceptance rate of these foods reflects infants’ positive reactions. The earlier vegetables were introduced, the higher the acceptance of new vegetables was. Finally, new food acceptance was significantly correlated with the number of different foods offered in the first two months of weaning, particularly for fruits and vegetables. These results highlight the ease of introducing new foods into a child’s diet in the period between 4 and 15 months and the role of maternal complementary feeding practices on infants’ acceptance of new foods.     

Effects of repeated exposure to either vegetables or fruits on infant’s vegetable and fruit acceptance at the beginning of weaning

This study investigated the effects of repeated exposure to either vegetables or fruits on an infant’s vegetable and fruit acceptance during the first 18 days of weaning. We hypothesized that repeated exposure to a type of vegetable or fruit, would increase its intake. Furthermore, we expected that being exclusively weaned with vegetables would result in a higher acceptance of vegetables than being exclusively weaned with fruits. To investigate this, a 19-day intervention study was conducted in 101 healthy infants, aged 4–6 months. Infants were randomly assigned to one of four treatment groups. Two groups received exclusively vegetable purées as targets every other day for 18 consecutive days; green beans was the target for one group and artichoke for the other group. The other two groups received exclusively fruit purées including either apple or plums as the target fruit. On day 19, the vegetable groups consumed their first fruit purée and the fruit groups their first vegetable purée. At the beginning of the study on days 1 and 2 and at the end on days 17, 18 and 19, the infants were fed fruit or vegetable purée in our laboratory. On days 3–16, the parents fed their infants the fruit or vegetable purées at home.Outcome variables were vegetable and fruit intake over time. Mean vegetable intake in the vegetable group increased significantly from 24 ± 28 g (mean ± SD) on days 1 and 2 to 45 ± 44 g on days 17 and 18. Fruit intake in the fruit group increased significantly from 46 ± 40 to 66 ± 42 g. Fruit intake was significantly higher than vegetable intake from the start. Repeated exposure to fruit had no effect on the vegetable intake. The first intake of green beans in the fruit groups at day 19, was 24 ± 29 g and on average as low as the green beans intake in the vegetable groups at the 1st exposure on days 1 or 2. Similarly, the first apple intake in the fruit groups on days 1 or 2 of 47 ± 48 g did on average not differ from the first apple intake of 45 ± 49 g in the vegetable groups on day 19. The mean intake of green beans and plums increased significantly after repeated exposure. The intake of the target food artichoke stayed low and the intake of apple only increased slightly. These findings confirm that at the first exposure fruit acceptance is higher than vegetable acceptance. Weaning with vegetables, but not with fruits, may promote vegetable acceptance in infants.     

Isolation of Enterobacter sakazakii and other Enterobacteriaceae from powdered infant formula milk and related products

The presence of Enterobacter sakazakii and other Enterobacteriaceae was surveyed in 82 powdered infant formula milk (IFM) and 404 other food products. The presence of Ent. sakazakii was detected using the conventional method (growth on violet red bile glucose agar plus yellow pigment production on TSA) and a new chromogenic medium (Druggan–Forsythe–Iversen agar, DFI) which enables results to be obtained 2 days earlier than the conventional method. Ent. sakazakii was isolated from 2/82 powdered IFM, 5/49 dried infant foods, 3/72 milk powder, 2/62 cheese products and various dry food ingredients, especially herbs and spices (40/122). Ent. sakazakii was isolated from 67 samples using the DFI medium, however only 19 of the samples were positive following the conventional method. The largest difference in isolation between the two methods was with dry food ingredients.Although Enterobacteriaceae were enumerated from one powdered IFM sample (Klebsiella ozaenae, 200 cfu/g), 7/82 had detectable Enterobacteriaceae after enrichment in EE broth. Using the ISO 6579 2002 method and immuno-magnetic separation technique no Salmonella serovars were isolated from powdered IFM, dried infant foods or milk samples. Therefore hygienic production of powdered IFM and milk production as monitored by control of Salmonella and enumeration of Enterobacteriaceae did not control Ent. sakazakii.     

The activity of single gliadin components in a foetal chick intestine assay for coeliac disease

 The in vitro methods proposed for estimating calcium bioavailability can be useful in studying the effect of dietetic factors. The aim of our work was to study the possible influence of different infant formula components – calcium, phosphorus, lactose, citric acid, ascorbic acid and proteins – on calcium bioavailability, considering dialysability to be an estimate of bioavailability. The 1981 method of Miller et al. with slight modifications (concerted action n^o 10 – FLAIR project) was applied to 18 commercial infant formulas of six different types: adapted, follow-up, preterm, hydrolysates, lactose-free and soy-based. Significant positive linear correlations between the amount of calcium dialysed and the calcium and phosphorus contents were found. However, there were no statistically significant correlations between the amount of calcium dialysed and the lactose, ascorbic acid or citric acid contents, In the case of proteins an exponential relationship was found between the amount of calcium dialysed and the protein content. Received: 21 April 1998 / Revised version: 5 October 1998     

A Docosahexaenoic Acid-Functional Food During Pregnancy Benefits Infant Visual Acuity at Four but not Six Months of Age

Within the visual system, docosahexaenoic acid (DHA, 22:6n−3) is an important structural component for retinal photoreceptors and cortical gray matter. There is a marked decrease in neural DHA accumulation in the face of DHA deficiency. DHA is accumulated at an accelerated rate during pregnancy, especially in the third trimester. However, pregnant women in the US and Canada have dietary DHA intakes that are significantly below the optimal level. The main objective of this study was to determine whether a DHA-functional food during pregnancy would benefit infant visual acuity at four and six months of age measured behaviorally using the acuity card procedure (ACP). In a randomized, longitudinal, double-blinded, and placebo-controlled trial, 30 pregnant women received either the DHA-functional food (n = 16) or the placebo (n = 14). There were significant main effects for visual acuity at four months of age (P = 0.018). The mean acuity scores were 3.8 ± 1.1 cycles/degree in the DHA group versus 3.2 ± 0.7 cycles/degree in the placebo group. At six months there were no group differences. Based on our results, we conclude that DHA supplemented during pregnancy plays a role in the maturation of the visual system.     

Indoor and outdoor air concentrations of BTEX and determinants in a cohort of one-year old children in Valencia, Spain

BTEX is the commonly used term for a group of toxic compounds (benzene, toluene, ethyl benzene, ortho-xylene and meta- and para-xylene), some of which, most notably benzene, are known carcinogens. The aim of this study is to measure the BTEX levels both inside and outside the homes of 352 one-year old children from the Valencia cohort of the INMA study (Spain) and to analyze the determinants of these levels. Passive samplers were used to measure BTEX levels during a 15 day period and a questionnaire was administered to gather information on potentially associated factors (sociodemographics, residential conditions, and lifestyle). The average concentrations of benzene, toluene, ethyl benzene, ortho-xylene, and meta- and para-xylene were 0.9, 3.6, 0.6, 0.6, and 1.0 μg/m³, respectively. On average, the indoor levels of all the compounds were approximately 2.5 times higher than those observed outdoors. Factors associated with higher BTEX concentrations inside the home were being the child of a mother of non-Spanish origin, living in a house that had been painted within the last year, living in an apartment, and not having air conditioning. Higher outdoor concentrations of BTEX depend on the residence being situated in a more urban zone, being located within the city limits, having living in a building with more than one story, residing in an area with a greater frequency of traffic, and the season of the year in which the sample was taken. The data thus obtained provide helpful information not only for implementing measures to reduce exposure to these pollutants, but also for evaluating the relation between such exposure and possible health risks for the children in the cohort.     

育儿园建筑设计初探

在当今社会,愈来愈多的国家认识到,促进人类的发展与进步,必须从0岁开始关注婴幼儿的成长和教育。我国大力发展为0-3岁婴幼儿提供早期保育和教育服务的机构是当务之急。如何创造婴幼儿的适宜发展空间,为教养者提供社交的机会,为管理人员、教师及服务人员提供舒适高效的工作环境是研究重点。本文将针对育儿园建筑设计进行分析和研究。