In vitro and in vivo assessment of the glycemic index of bakery products: influence of the reformulation of ingredients

Purpose

To evaluate whether the modification of ingredients of two bakery products, muffins and bread, reduces their glycemic index, by means of in vitro and in vivo procedures.

Methods

In vitro and in vivo glycemic index were evaluated for two types of bread and two types of muffins including one standard product for each category. For the in vitro determination, kinetics of starch digestion method was used. For the in vivo procedure, postprandial glucose measured as IAUC was obtained in a group of eighteen healthy volunteers (ten did the test with muffins and eight with breads).

Results

In in vitro, a reduction in the expected glycemic index regarding the control muffin was achieved with the partial substitution of wheat flour by a mixture of resistant starch, dextrin and lentil flour. In breads, with the partial substitution of wheat flour by a mixture of resistant starch and dextrins, a decrease in the expected glycemic index was also observed. In in vivo, a reduction in GI was also achieved both in muffin and in bread. All the obtained GI was higher in in vitro method.

Conclusions

Despite the fact that in vitro overestimate in vivo method, the trend in the reduction in GI seems to be similar in both methods. With the substitution assayed, a reduction in the expected glycemic index and the glycemic index were obtained both in muffins and in breads.     

Fatty acid composition of sweet bakery goods and chocolate products and evaluation of overall nutritional quality in relation to the food label information

The study aimed to determine fatty acid (FA) composition of some sweet bakery goods and chocolate products on Turkey market (n = 35) and to evaluate their overall nutritional quality in relation with the nutritional facts on the label. Moreover,“trans fatty acid (TFA)-free” declaration on the label was checked with the current labelling regulations in Turkey. Majority of the sample groups represented the prevalence of palmitic and oleic acid; on the other hand, it was difficult to specify a sample group with a specific FA. Erucic acid, for which European Commission set maximum limits, was not detected in any of the samples. It was observed that total saturated fatty acids (SFA) constituted more than 44 % of total FA. In all cases, total TFA content was lower than 1 % of total FA. Based on nutritional facts on the label, that type of products provide higher energy with the main source of fat and carbohydrates. Therefore, consumption of those products in a diet should be limited not to gain an excess amount of body weight and to have adverse health effects related to higher SFA content. This study can be regarded as a case surveillance study by providing updated data that can be used by Nutritionals and authorities to make risk assessments on consumer health.     

Nutritional and sensory challenges of gluten-free bakery products: a review

There is a growing need for gluten-free bakery products. Currently, gluten-free bakery products deliver lower protein, fibre and mineral content and elevated glycaemic index (GI) than gluten-containing foods. Only a mixture of rice and buckwheat flour or a low addition of either egg white or whey protein, has shown potential for the improvement of both nutrition and sensory qualities. To increase the fibre content, isolated cereal fibre and soluble fibre isolates have been incorporated into gluten-free formulations with some sensory success. Studies have shown that the GI of modern gluten-free products is no longer a major concern with the improvement of ingredient formulations and processing methods. The currently low mineral content can be increased with the use of mineral-rich ingredients such as amaranth, buckwheat or flaxseed flour. Nonetheless, consumers still show a preference to refined, low fibre breads over wholegrain fibre-rich bread.     

Assessment of hydroxymethylfurfural and furfural in commercial bakery products

A survey was conducted on the presence of hydroxymethylfurfural (HMF) and furfural in bread and bakery products; for this purpose a reliable extraction procedure followed by high performance liquid chromatography (HPLC) was applied. The performance of the method was evaluated in terms of linearity (r always > 0.99); detection limits (0.001 mg L⁻¹ for furfural and 0.006 mg L⁻¹ for HMF); recovery percentages (98.5–100.5% for HMF and 94.9–98.9% for furfural); intraday precision (<4.65%) and interday precision (<7.51%). Two batches of a wide variety of products commercially available were analysed (a total of 88 samples). HMF and furfural levels presented high variability between products and batches of the same product. Cake/pastry samples showed the lowest HMF content (3.0 mg kg⁻¹ fw) while biscuits showed the highest content (7.8 mg kg⁻¹ fw) (p < 0.05). Regarding furfural, bread samples presented the highest furfural content (5.3 mg kg⁻¹ fw) (p < 0.05), cake/pastry and biscuits showed the lowest content (1.9 and 3.0 mg kg⁻¹ fw, respectively). Chocolate containing samples presented higher amounts of furfural (>20 mg kg⁻¹). These results indicate that special attention should be given to furfural content of bread (due to its daily high consumption) and re-evaluation of dietary exposure.     

Lactobacillus plantarum ITM21B fermentation product and chickpea flour enhance the nutritional profile of salt reduced bakery products

The study aimed at improving the nutritional profile of yeast leavened salt reduced sliced bread and puccia type bread fortified with a wheat-based Lactobacillus plantarum ITM21B fermentation product (Bio21B). The protein content of bread made under laboratory conditions was increased by using: (i) chickpea flour (CF) (15% wt/wt flour) and Bio21B or (ii) the Bio21B containing a fungal protease to favour the gluten hydrolysis. Products showed increased protein and total amino acid content and improved protein digestibility. Moreover, the formula significantly affected the protein pattern of breads which, according to the results of the microfluidic two-dimensional electrophoresis (μ2DE) protein pattern, were discriminated as observed by the PCA plot. The use of CF was validated at industrial pilot plant producing salt reduced sliced bread and puccia type bread. The resulting products showed improved nutritional profile and a sensory quality comparable to the company’s products containing salt.     

Platelet aggregation,thromboxane production and thrombogenic ratio in postmenopausal women consuming high oleic acid-sunflower oil or palmolein

Summary. Background: Saturated fatty acids exert controversial effects on platelet aggregation and eicosanoid production. Aim: To investigate the effect of a dietary exchange between palmitic acid and oleic acid on both platelet aggregation and thromboxane B2 (TXB₂) production, and on urine TXB₂, prostacyclin I2 (PGI₂ as 6-keto-protaglandin F₁), and the thrombogenic ratio (TXB₂/6-keto-protaglandin F₁) in fourteen postmenopausal women. Experimental design: Women were assigned to two consecutive 28-d dietary periods that were high in cholesterol (~400 mg/d) and fat (~46%en). In the first period all subjects followed an oleic acid-rich diet prepared with high oleic acidsunflower oil. This was followed by a second period rich in palmitic acid in the form of palmolein. Determinations: Nutrient intakes, ADP-platelet aggregation, platelet TXB₂ production, urine TXB₂ and 6-keto-protaglandin F₁ were measured during two dietary periods and the results obtained correlated to serum cholesterol, lipoproteincholesterol and peroxides, apolipoproteins and plasma tocopherol. Results: The palmolein diet led to an increase in the platelet aggregation rate (p < 0.05) and in the time for the maximal aggregation rate (p < 0.02).No significant differences were observed in platelet TXB₂ production. Palmolein increased urine TXB₂ in pg/mL (p < 0.05) and pg/min (p < 0.01), whereas the thrombogenic ratio (TXB₂/6-keto-protaglandin F₁) did not change. Most changes were related to oil change, few to serum cholesterol level (< or 6.2 mmol/L) or age (< or 65 yr). Conclusions: Palmolein diet activates platelet aggregation more in normocholesterolemics. Though palmolein increased thromboxane and tended to increase prostacyclin in urine in normo- and hypercholesterolemic women, the thrombogenic ratio did not change. These effects were related to the LDL and HDL concentration increases and to the absence of change in the total cholesterol/HDL-cholesterol ratio found following the dietary intervention.     

Impact of health claims in prebiotic-enriched breads on purchase intent,emotional response and product liking

The impact of health claims on purchase intent, emotional response and liking has never been previously reported. In this study, prebiotic-enriched bread was used as a model functional food. Purchase intent, emotional response and liking were investigated in three phases: (1) focus groups were used to gauge consumer perception of health claims and functional foods, (2) the impact of health claims on purchase intent and emotional responses were measured using an online survey (n?=?122) and (3) hedonic ratings on bread rolls presented with or without any associated claims were obtained (n?=?100). A cluster analysis of the purchase intent data identified two clusters of consumers who were either receptive or non-receptive to health claims. Receptive and non-receptive consumers significantly differed in the emotions they reported with respect to the claims. The hedonic ratings did not significantly differ between the breads tasted with or without health claims.     

Sensory analysis and consumer surveys of fat- and salt-reduced meat products and their use in an energy-reduced diet in overweight individuals

Meat and meat products are of high nutritional value; however, they frequently provide salt and fat in high amounts, which can have negative health effects when consumed in excess. We investigated salt- and fat-reduced meat products, i.e. sensory evaluation and consumer surveys were carried out as well as a dietary intervention study was carried out in overweight individuals who used salt- and fat-reduced products as a part of an energy-restricted diet. Although differences were detected in the sensory evaluation between reduced and regular meat products, the participants in the consumer surveys and in the dietary intervention study gave good ratings for the fat and fat-reduced meat products. The intervention study led to weight loss and improved cardiovascular risk, but did not reveal side effects associated with the consumption of these products. Our study indicates that such products are well accepted by potential consumers and can be included successfully in a weight loss programme.     

家庭环境对学龄前儿童电子产品使用影响

目的了解江苏省扬州城区学龄前儿童电子产品使用现状,探讨不同家庭环境对学龄前儿童电子产品使用的影响,为正确指导使用电子设备,促进身心健康提供科学依据。方法于2015年4—5月采用分层整群随机方法抽取7所幼儿园共2 531名在园儿童,对其进行问卷调查,收集一般人口统计学特征及电子产品使用情况。结果98.00%的儿童每天使用1种以上电子产品,时间>1 h/d的占63.53%。触屏电子产品每天使用总频率为67.05%,>1 h/d的为15.21%。每天使用电子产品总时间为(1.68±1.45)h,最主要的是电视机,其次为手机和平板电脑,且周末较工作日使用时间更长。单因素分析发现,学龄前儿童使用电子产品主要与年龄、父母文化程度、家庭收入及主要带养者相关;多因素logistic回归分析发现,母亲文化程度低(OR=6.45)及祖辈及其他人带养(OR=1.63)为其危险因素。结论扬州城区学龄前儿童使用电子产品频率较高,尤其是父母文化程度低、祖辈及其他人带养的人群,家长应对其进行科学管理与教育,合理使用电子产品。     

贵州省即食米面制品食源性致病菌污染及病原特征分析

目的 了解贵州省即食米面制品中食源性致病菌污染状况和病原学特征,为细菌性食源性疾病的防治提供参考依据。方法 2014—2019年在贵州省的88个县（市、区）采集即食米面制品1128份,依据食品安全国家标准（GB4789）进行五种食源性致病菌的检测;采用荧光定量PCR法和ELISA法分别检测金黄色葡萄球菌肠毒素基因及蛋白,普通PCR法检测蜡样芽胞杆菌毒力基因。结果 1128份即食米面制品有130份样品检出食源性致病菌,检出率为11.52%,分别是蜡样芽胞杆菌7.71%,金黄色葡萄球菌3.10%,沙门氏菌0.27%,单核细胞增生李斯特氏菌0.44%,未检出致泻大肠埃希氏菌。分离的35株金黄色葡萄球菌有65.71%携带肠毒素基因,54.29%呈肠毒素蛋白阳性。87株蜡样芽胞杆菌都至少携带两种以上毒力基因,同时携带hblACD及nheABC的有29.88%。结论 贵州省即食米面制品存在多种食源性致病菌污染,蜡样芽胞杆菌和金黄色葡萄球菌污染率较高且携带多种毒力基因,存在较大食源性疾病风险,监管部门应加强对即食米面制品的加工制作管理。     

Influence of organic acids on rheological and bread-making characteristics of fortified wheat flour

Flour was fortified with premix containing ferrous fumarate and folic acid. Organic acids such as citric acid, malic acid and tartaric acid, which are promoters of iron bioavailability, were added at three levels and their influence on rheological and bread-making characteristics was studied. Farinograph water absorption increased with fortificants, but with addition of organic acids there was a decrease. Maximum pressure was 77 mm in control, which increased to 78–88 mm with the addition of different acids to the fortified flour. Addition of organic acids to fortified flour brought about a decrease in peak viscosity, hot paste viscosity, cold paste viscosity and setback values. The L, a and b values of fortified breads were similar to that of control. Sensory analysis revealed marginal differences in the overall quality of breads prepared with fortified flour with the addition of organic acids.     

Effects of feeding polydextrose on faecal characteristics, microbiota and fermentative end products in healthy adult dogs

Polydextrose is a potential prebiotic, but has not been well tested in dogs. Thus, the objective of the present study was to determine the effects of polydextrose on faecal characteristics, microbial populations and fermentative end products in healthy adult dogs. A total of eight adult hound dogs (3.5 (sem 0.5) years; 20 (sem 0.5) kg) were randomly allotted to one of four test diets containing the following concentrations of polydextrose: (1) 0 % (control); (2) 0.5 %; (3) 1.0 %; or (4) 1.5 %. A Latin square design was used, with each treatment period lasting 14 d (days 0-10 adaptation; days 11-14 fresh and total faecal collection). All dogs were fed to maintain body weight. Data were evaluated for linear and quadratic effects using SAS software. Although apparent total tract DM digestibility was unaffected, total tract crude protein digestibility tended to decrease (P < 0.10) linearly with increasing dietary polydextrose concentrations. Fresh faecal DM percentage tended to decrease (P < 0.10) linearly, while faecal scores increased (P < 0.05; looser stools) with increasing dietary concentrations of polydextrose. Faecal acetate, propionate and total SCFA concentrations increased (P < 0.05) linearly with increased dietary polydextrose. Faecal pH decreased (P < 0.05) linearly with increasing polydextrose. Faecal indole tended to decrease (P < 0.10) linearly with increasing polydextrose, but other faecal protein catabolites were not changed. Faecal Clostridium perfringens linearly decreased (P < 0.05) with increasing dietary polydextrose concentrations, but Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. were not affected. Based on the present results, polydextrose appears to act as a highly fermentable fibre, but requires further research to test its potential as a prebiotic in dogs.     

Effect of two bakery products on short-term food intake and gut-hormones in young adults: a pilot study

The aim of this study is to compare the effect of conventional bread and a whole grain bread on appetite and energy intake, satiety and satiety gut-hormones. A randomized controlled crossover pilot study was carried out in 11 university students (age: 18.7?±?0.9 years; body mass index: 22.7?±?2.7?kg/m²). Participants consumed two different mid-morning cereal-based snacks, including a conventional or whole grain bread. Two testing days were completed, including satiety questionnaires, blood sampling and consumption of standardized breakfast, mid-morning test-snacks and ad libitum lunch. Several gut-hormones were analysed and satiation was assessed using Visual Analogue Scale scores. The consumption of whole grain bread increased satiety perception, decreased the remained energy intake during the testing day, and decreased the postprandial response of peptide YY, compared with conventional bread (p?相似文献   

Plasma levels of advanced glycation end products in healthy, long-term vegetarians and subjects on a western mixed diet

Summary Background Evidence indicates that food-derived Maillard's reaction products are absorbed and yet can be detected in the circulation. Aim of the study We postulated that consumption of the heat-treated food by omnivores could be reflected by higher plasma levels of advanced glycation end products (AGEs) in comparison with vegetarians, who in cooking (by keeping away from meat) use lower temperatures and less time for heating. Methods Plasma fluorescent AGEs (350/450 nm) and Ne-(carboxymethyl)lysine (CML, competitive ELISA) levels were investigated in 3 groups of healthy vegetarians (9 vegans-V, 19 lacto-ovo-vegetarians – VLO and 14 semi-vegetarians – VS) and compared with those of age-matched omnivores (O, n=19). Mean duration of vegetarian diet was V: 7.2±1.0, VLO: 8.2±0.8 and VS: 7.9±1.1 years. Results Both fluorescent AGE (O: 9.9±0.5; V: 10.8±0.7, LO: 13.1±0.8* and SV: 11.6±1.2 ×10³ AU), and CML levels (O: 427.1±15.0, V: 514.8±24.6*, LO: 525.7±29.5**, SV: 492.6±18.0* ng/ml) were significantly lower in omnivores than in vegetarians. Plasma glucose, parameters of renal function (plasma concentration of creatinine and cystatin C, calculated glomerular filtration rate – GFR) as well as C-reactive protein levels were within the normal range and did not differ significantly between the groups. Thus, neither decline of kidney function nor inflammatory processes contributed to the rise in plasma AGEs. Conclusion Enhanced plasma AGE levels in vegetarians in comparison to omnivores are herein presented for the first time. Mechanisms of AGE elevation and potential pathophysiological relevance of this finding are to be elucidated in prospective studies. Received: 18 June 2001, Accepted: 7 November 2001     

水产品中霍乱弧菌的监测方法研究

目的:研究水产品中霍乱弧菌的监测方法,及时发现被霍乱弧菌污染的水产品,采取有效防控措施,防范霍乱疫情的发生。方法:用实时荧光PCR法、胶体金法、分离培养法三种方法分别对180份水产品进行霍乱弧菌检测,阳性样品再进行霍乱肠毒素检测。结果:三种方法检出了44份核酸阳性标本,18份霍乱肠毒素阳性标本,分离出8株霍乱弧菌。结论:在进行水产品霍乱监测时,可以先用实时荧光PCR进行初筛,筛出核酸阳性标本,进行霍乱肠毒素检测,及时发现被霍乱产毒株污染的水产品,再对筛出的核酸阳性标本结合胶体金法进行分离培养和分型鉴定,进一步完成霍乱疫情的确证和分析。     

淀粉在西式香肠中的作用研究

本文使用仪器设备测定和感官评定的方法,对添加木薯淀粉的西式香肠的感观质量进行研究,结果表明:添加4％木薯淀粉能改善西式香肠的色泽、嫩度、弹性、口感及组织状态等(P<0.05),而对风味等无不良影响(P>0.05);此外,随着储藏期的增长(2天→7天),香肠色泽均变暗(P<0.05)。     

南京市乳制品中β-内酰胺酶类药物残留状况调查

目的：调查南京零售牛乳制品中添加生鲜牛乳抗生素分解剂—β-内酰胺酶的比例。方法：按照卫生部颁发的＂乳及乳制品中舒巴坦敏感β-内酰胺酶类药物检验方法—杯碟法＂检测。结果：10个品牌的乳制品样品中共有5个品牌检出β-内酰胺酶,检出率达到50.0%;同一品牌的不同样品中,检出率在12.5%~33.3%之间。结论：南京市乳制品中不仅检测到β-内酰胺酶,且添加率较高,应当采取措施杜绝β-内酰胺酶在乳制品中的使用。     

河南省《速冻面米制品》（GB19295 - 2011）国家标准跟踪结果分析

目的 了解《速冻面米制品》（GB19295—2011）贯彻落实和执行情况,调查标准指标或技术要求的科学性和实用性,为该标准修订提供资料。方法 通过跟踪评价,收集了专家、企业、监督、检测单位在标准使用过程遇到的问题和反馈的意见和建议。结果 本次共向食品专家、速冻食品企业、监督、检测单位发出问卷139份,收回问卷112份,有效问卷101份,有效问卷回收率72.7%。共有44人提出了131条意见和建议。从层级上看,省级专家、监督、监测人员和大型企业反馈意见较多,基层较少。从被调查的4类人员看,专家和检测检验人员反馈问题较多,分别有56.7%和60.0%的人反馈意见,人均反馈意见1.83和1.75条。速冻面米制品企业最少,只有25.8%的人反馈意见,人均0.52条。结论 通过跟踪评价发现,随着食品安全标准不断的发布,本标准的指标和标准值已有所欠缺,建议及时进行修订和完善。为了更好地贯彻执行标准,必需加大标准的培训力度,特别是中小型速冻食品企业。     

泰州市112份水产品中副溶血性弧菌检出状况及耐药性分析

目的 了解泰州市市售水产品副溶血性弧菌污染状况及对常用抗菌药物的敏感性,为有效的预防副溶血性弧菌食物中毒提供实验依据。方法 根据《食品微生物学检验 副溶血性弧菌检验》( GB/T 4789.7—2010)对112份水产品样品进行副溶血性弧菌检测,分离菌株的药敏实验采用K - B法。结果 112份样品38份检出副溶血性弧菌,副溶血性弧菌的检出率为 33.9%。副溶血性弧菌分离株对氨苄西林耐药率为52.6%,对头孢西丁、头孢噻肟、四环素、环丙沙星、庆大霉素、氯霉素、萘啶酸、复方新诺明敏感率为100.0%。结论 市售水产品中副溶血性弧菌污染较严重,并有部分菌株耐药。     

花生及其制品中16种真菌毒素的超高效液相色谱串联质谱测定法

目的 建立花生及其制品中16种真菌毒素包括黄曲霉毒素(AF)、伏马菌素(FB)、赭曲霉毒素A(OTA)等的超高效液相色谱串联质谱测定法。方法 样品经研磨粉碎后酸性乙腈溶液提取,10 000 r/min离心后用水稀释,再经2℃低温10 000 r/min离心后加入同位素内标,多反应离子监测模式(MRM)检测,内标法定量。结果 16种待测物线性关系良好,相关系数均大于0.9900,方法定量限为0.3μg/kg～45.0μg/kg,加标回收率在72.7%～126.3%之间,相对标准偏差为1.3%～5.0%。采用优化后方法对60份花生及其制品包括花生油、花生酱、生花生和熟花生进行检测,AFB₁、AFB₂和AFG₁的总检出率分别为35%(21/60)、 18.3%(11/60)、5.0%(3/60),含量范围分别为0.1μg/kg～57.5μg/kg, 0.1μg/kg～18.4μg/kg, 0.1μg/kg～3.3μg/kg。结论 该法前处理快速、简捷、灵敏度高、准确度好,适合于花生及其制品中16种真菌毒素快速检测。