Ability of some food preservation processes to modify the overall nutritional value of food

The impact of food transformations on final nutritional quality of food products is a major question that has been studied only partially. This paper propose an assessment of different preservation processes with the light of two overall nutritional scores, positive (SAIN) and negative (LIM), developed in 2008, in response to a European regulation made to improve nutritional information on processed food. With the example of two different products, apple and pork meat, the objective is to monitor the nutritional scores as a function of the preservation operation chosen, isolated or combined, traditional or innovative. The results show that nutritional scores are very different as a function of the mass transfers involved during the preservation operation. The results give insights in the ability of a technological choice to modify the nutritional quality of a food item and potentially orientate a food label. This work also shows the limitations of using global nutritional scores as a tool to evaluate a food process.     

Wheat (Triticum aestivum L.) Bran in Bread Making: A Critical Review

Wheat bran, a by‐product of the industrial roller milling of wheat, is increasingly added to food products because of its nutritional profile and physiological effects. Epidemiological data and scientific studies have demonstrated the health benefits of consuming bran‐rich or whole‐grain food products. However, incorporation of wheat bran in cereal‐based products negatively affects their production process. Furthermore, the organoleptic quality of the obtained products is mostly perceived as inferior to that of products based on refined wheat flour. This review summarizes the current knowledge on the impact of wheat bran on bread making, provides a comprehensive overview of the bran properties possibly involved, and discusses different strategies that have been evaluated up till now to counteract the detrimental effects of wheat bran on bread making.     

A study on thermal stability of lycopene in tomato in water and oil food systems using response surface methodology

Thermal processed tomato‐food products rich in Z‐lycopene isomers have demonstrated higher bioactivity compared to fresh products which contain mainly all‐E‐lycopene isomer. The objectives of this study were to optimise processing conditions for production of tomato products rich in Z‐lycopene isomers in water and oil systems. The results showed that the optimal conditions for water and oil systems were temperature 120 °C, heating time 2.14 h, and the percentage of Z‐lycopene isomers content was 51 ± 1% and 57 ± 2%, respectively. The ratio of tomato extract to oil/water had no influence on the Z‐lycopene formation. Therefore, from these results it can be concluded that the combination of high temperature and relatively short heat treatment time could improve formation of Z‐lycopene isomers or degradation of Z‐isomers is lower during tomato processing .These research results could be useful in assisting the industry to improve processing technology, nutritional value and health‐benefits of tomato‐based foods.     

Effect of pilot-scale aseptic processing on tomato soup quality parameters

Tomatoes are often processed into shelf-stable products. However, the different processing steps might have an impact on the product quality. In this study, a model tomato soup was prepared and the impact of pilot-scale aseptic processing, including heat treatment and high-pressure homogenization, on some selected quality parameters was evaluated. The vitamin C content, the lycopene isomer content, and the lycopene bioaccessibility were considered as health-promoting attributes. As a structural characteristic, the viscosity of the tomato soup was investigated. A tomato soup without oil as well as a tomato soup containing 5% olive oil were evaluated. Thermal processing had a negative effect on the vitamin C content, while lycopene degradation was limited. For both compounds, high-pressure homogenization caused additional losses. High-pressure homogenization also resulted in a higher viscosity that was accompanied by a decrease in lycopene bioaccessibility. The presence of lipids clearly enhanced the lycopene isomerization susceptibility and improved the bioaccessibility. PRACTICAL APPLICATION: The results obtained in this study are of relevance for product formulation and process design of tomato-based food products.     

Are nutritional warnings more efficient than claims in shaping consumers’ healthfulness perception?

Nutritional warnings highlighting high content of nutrients associated with non-communicable diseases have been recently proposed as a tool to facilitate the identification of unhealthful products. However, several different cues raising positive healthful associations are usually included on food packages, which can reduce the effectiveness of nutritional warnings. This study aimed to evaluate the effect of nutritional warnings and claims on the perceived healthfulness of four product categories, frequently consumed in Brazil: yogurt, juice, bread and crackers. For each category, eight packages were designed following a full-factorial experimental design with three two-level factors: two types of claims (present vs. absent) and nutritional warnings highlighting high content of saturated fat, sugar and/or sodium (present vs. absent). A total of 820 adults participated in an online survey. They were randomly divided into four groups, each of which evaluated the packages of one product category. For each package, participants were asked to rate their perceived healthfulness using a 7-point scale (1: not healthy at all; 7: very healthy). Data were analyzed using ANOVA considering main effects and interactions. Results showed that although claims had a significant and positive effect on the perceived healthfulness of all categories, nutritional warnings had the largest relative importance and significantly decreased perceived healthfulness. Participants who were more willing to compromise pleasure for health tended to give more relative importance to the warnings. Results suggest that nutritional warning could facilitate the identification of products with unfavorable nutrient profile and can contribute to override the positive healthful associations generated by claims.     

Significance of osmotic temperature treatment and storage time on physical and chemical properties of a strawberry-gel product

BACKGROUND: The development of fruit‐based foods that maintain the nutritional and sensory properties of fresh fruit may help to stimulate fruit consumption by consumers. The possibility of formulating a fruit‐gel product with osmodehydrated fruit and the reused osmotic solution (OS) obtained from the dehydration step has been demonstrated. However, the conditions of the osmotic process can significantly affect the properties of the obtained product. In this work an osmotic process at 22 °C for 6 h and at 30 °C for 3 h was employed to formulate a strawberry‐gel product. RESULTS: Significant losses of ascorbic and citric acids and anthocyanins were observed and some relevant volatile compounds of the strawberry aroma profile were developed during the osmotic process. Changes in all analysed parameters occurred mainly during the first 2 days of storage. The flux of anthocyanins from the fruit to the gel gave an attractive appearance to the formulated product. These changes were more marked for samples obtained at 30 °C. CONCLUSION: Osmotic treatment at 30 °C was more suitable for formulation of the product, because the presence of nutritional/functional compounds in the OS, and consequently in the gel matrix, was higher and the aroma and colour were more stable and homogeneous during storage. Copyright © 2011 Society of Chemical Industry     

Preliminary studies on the effect of processing on the IgE reactivity of tomato products

Tomatoes and tomato products, obtained from a market, from companies or prepared in research laboratories, were tested in order to investigate how different processes could modulate the IgE reactivity of these products. The protein fraction of the samples was extracted by using a low‐temperature method in order to avoid degradation, and then separated on SDS PAGE to evaluate the protein profile. All the separated samples were blotted onto nitrocellulose membranes and then individually tested with pooled human sera that had been obtained from patients allergic to tomato, in order to evaluate the potential IgE binding of the protein bands. Heat treatments conventionally employed for the production of tomato‐based products were found to strongly degrade proteins thus dramatically reducing their IgE reactivity; characteristic protein profiles were found for specific processes such as hot and cold break. Ultra‐high‐pressure treatments were found to generally preserve the integrity of tomato proteins and this was reflected by the unaltered IgE reactivity observed. Copyright © 2007 Society of Chemical Industry     

Chemical characterization of tomato pomace

Tomato‐processing by‐product, also known as tomato pomace, consists of peel and seeds and represents around 4% of the fruit weight. If these wastes remain unused, they not only add to the disposal problem but also aggravate environmental pollution. The aim of this paper is to evaluate the chemical composition of tomato pomace collected at different steps during industrial processing in order to assess the quality of this by‐product. Twenty‐one tomato pomace samples were considered for analysis. Samples corresponded to different steps during tomato processing for paste: seven after pulper, five after finisher, six before turbopress and three after turbopress. Samples were analyzed for moisture content, total and soluble sugars, protein, fat, soluble and total fiber, as well as mineral content. From the results obtained we can conclude that tomato pomace composition (in dry weight basis) is as follows: 59.03% fiber, 25.73% total sugars, 19.27% protein, 7.55% pectins, 5.85% total fat and 3.92% minerals. Copyright © 2006 Society of Chemical Industry     

Kinetic modelling of textural changes in ready-to-eat breakfast cereals during soaking in semi-skimmed milk

Summary Ready‐to‐eat breakfast cereals immersed in milk undergo undesirable changes in texture because of sudden moisture uptake. The textural changes are ascribable to a plasticizing effect of water, which modifies the mechanical strength of products by softening the starch/protein matrix. In this work, some textural parameters of different cereal flakes were derived from the force–displacement curves monitored during 300 s of immersion in milk. Hardness loss, deformability increment and changes in the force–displacement curve profile were calculated and plotted against soaking time. The application of a sugar coating process to a model cereal flake increased the initial product hardness and improved the preservation of the textural parameters during immersion. The Peleg model closely fitted the experimental data, with regression coefficients from 0.967 to 0.999.     

Effect of thermal processing on the degradation, isomerization, and bioaccessibility of lycopene in tomato pulp

Thermal processing affects the nutritional value of food products. The nutritional value is not only determined by the content but also by the bioaccessibility of nutrients. The present study was performed to gain detailed insight into the influence of thermal processing on the degradation, isomerization, and bioaccessibility of lycopene isomers in tomato pulp, without adding any other ingredient. The bioaccessibility, which is defined as the fraction of the nutrient that can be released from the food matrix, was measured using an in vitro method. The results demonstrated the rather high thermal stability of lycopene. Although a treatment at 140 °C induced isomerization, the contribution of cis-lycopene to the total lycopene content remained small. Results also confirmed that thermal processing as such can improve the in vitro bioaccessibility of lycopene in tomato pulp, but the improvement was only significant upon treatments at temperatures of 130 and 140 °C. At such intense process conditions, one should be aware of the negative effect on other quality and nutrient parameters. Possibilities of thermal processing as such to improve the nutritional value of tomato pulp (without the addition of other ingredients) thus looks rather limited.     

NUTRITIVE CONTENT OF CANNED TOMATO JUICE AND WHOLE KERNEL CORN

Most of the information on the nutritive value of canned foods in the technical literature was obtained 25–30 years ago. A resurvey of the nutrient content of canned tomato juice and canned whole kernel corn has been carried out on a nation-wide basis with sampling methods directly comparable to the older survey procedures. Although there have been extensive changes in varietal types and processing methods during the past 30 yr the mean nutritional values for these products have changed very little. Comparison of the nutrient values for these products listed in USDA Handbook No. 8 reveals no differences that could not be attributed to seasonal variations. A possible exception is the ascorbic acid content of tomato juice, which for the 1969 season was found to be somewhat lower than the listed value. While sample-to-sample variation is small in terms of the RDA of most nutrients, it can be critical in terms of the regulatory requirements proposed for nutritional labeling. Under this proposal canners would have to grossly "under declare" some nutrients such as ascorbic acid in order to ensure compliance. The indication is that mean values derived from adequate sampling programs are relatively stable although the population may encompass wide ranges of variability. For this reason, nutrient labeling declarations based upon properly constituted average values provide the most practicable solution to the inherent technical problems in the proposed nutritional labeling regulation     

A three-prong strategy to develop functional food using protein isolates recovered from chicken processing by-products with isoelectric solubilization/precipitation

BACKGROUND: Skin‐on bone‐in chicken drumsticks were processed with isoelectric solubilization/precipitation to recover muscle proteins. The drumsticks were used as a model for dark chicken meat processing by‐products. The main objective of this study was conversion of dark chicken meat processing by‐products to restructured functional food product. An attempt was made to develop functional food product that would resemble respective product made from boneless skinless chicken breast meat. A three‐prong strategy to address diet‐driven cardiovascular disease (CVD)with a functional food was used in this study. The strategy included addition of three ingredients with well‐documented cardiovascular benefits: (i) ω‐3 polyunsaturated fatty acid‐rich oil (flaxseed‐algae, 9:1); (ii) soluble fiber; and (iii) salt substitute. Titanium dioxide, potato starch, polyphosphate, and transglutaminase were also added. The batters were formulated and cooked resulting in heat‐set gels. RESULTS: Color (L*a*b*), texture (torsion test, Kramer shear test, and texture profile analysis), thermal denaturation (differential scanning calorimetry), and gelation (dynamic rheology) of chicken drumstick gels and chicken breast gels were determined and compared. Chicken drumstick gels generally had comparable color and texture properties to the gels made from chicken breast meat. The endothermic transition (thermal denaturation) of myosin was more pronounced and gelation properties were better for the drumstick gels. CONCLUSION: This study demonstrated a feasibility to develop functional food made of muscle proteins recovered with isoelectric solubilization/precipitation from low‐value dark chicken meat processing by‐products. The functional food developed in this study was enriched with CVD‐beneficial nutrients and had comparable instrumental quality attributes to respective products made of chicken breast meat. Although the results of this study point towards the potential for a novel, marketable functional food product, sensory tests and storage stability study are recommended. Copyright © 2012 Society of Chemical Industry     

Consumer Valuations and Preference Heterogeneity for a Novel Functional Food

ABSTRACT:  Recent trends in the marketing of functional foods suggest that multiple-benefit products are becoming more common. Yet it is unclear which consumers are most interested in, or best served by, such novel or new generation functional foods. With emerging scientific evidence of efficacy and more diverse products offered for sale, a broader range of consumers are likely to become interested in dietary interventions to enhance health. Consumers will likely respond based on a range of motivation, health conditions, and knowledge levels suggesting "one size will not fit all." Given such an evolving marketing environment, this paper presents 1 research technique exploring differences in consumer preferences and valuations for a novel functional food product—a tomato juice containing soy. A discrete choice experiment is applied to examine consumer valuation of this novel functional food. Data were collected from 1704 households in Ohio through a mail survey. The choice experiment manipulates whether or not the product is organic, whether it contains natural or fortified nutrients, and product price. Estimates of consumer willingness to pay a premium price are based on conditional logit and mixed logit models, which permit an examination of consumer preference and valuation heterogeneity for key product attributes. Results indicate that health benefits and ingredient naturalness are positively valued, but such preferences and valuations depend on an individual's education, income, and food purchase behavior. Naturally occurring nutrients are preferred over fortification. Considerable heterogeneity is found in the data suggesting that a range of market segments may exist.     

References to home-made and natural foods on the labels of ultra-processed products increase healthfulness perception and purchase intention: Insights for policy making

As nutritional recommendations change, new marketing strategies are expected to appear on food labels to convey the idea that products are healthful and aligned with the recommendations. In this context, the objective of the study was to evaluate the effect of references to ‘home-made’, images of natural foods and nutritional warnings on consumers’ healthfulness perception and purchase intention of labels of ultra-processed products with excessive content of nutrients associated with non-communicable diseases (NCDs). The study was conducted with 790 Uruguayan Facebook users (65% female, 18–89 years old), diverse in terms of educational and socio-economic levels. A choice experiment involving labels of four categories of ultra-processed products (burgers, cookies, instant soup and instant vanilla milk custard) was implemented. For each product category, eight sets of two labels differing in the presence of references to home-made, images of natural foods and nutritional warnings were designed. Half of the participants were asked to indicate the healthier product, whereas the other half were asked to indicate the product they would purchase. Data were analyzed using mixed logit models. The inclusion of references to home-made and images of natural foods on the labels had a positive effect on purchase intention and tended to create the belief that products were healthful. Nutritional warnings decreased healthfulness perception and discouraged participants' choice. In three of the product categories images of natural foods created a health halo that reduced the effect of nutritional warnings on product choice. Results from the present work suggest the need to develop stricter labelling regulations for ultra-processed products with high content of nutrients associated with NCDs.     

Why for feed and not for human consumption? The black soldier fly larvae

With the surge in consumption of insects, the search continues to find ways to increase the popularity of insect‐based products in the Western world. The black soldier fly larvae (BSFL), which is mainly utilized for animal feed, has great potential to provide a sustainable source of nutrients for human food. This review aims to discuss some of the key benefits and challenges of BSFL and their potential role as a food ingredient and/or product for human consumption. Few articles specifically discuss BSFL as a food source, therefore a comprehensive literature search strategy consisted of collecting and evaluating published data about BSFL as animal feed that could be relevant to its use in food. The hurdles that need to be overcome in order to introduce BSFL as a viable food option include safety concerns, technofunctional properties, nutritional aspects, consumer attitudes, and product applications for BSFL.     

基于主成分分析验证气调对番茄品质的影响

研究低温环境下不同体积分数的混合气体对番茄感官品质、营养价值的影响。以番茄作为试验研究对象,通过预冷处理,选择开孔率5%的聚乙烯食品包装袋包装,放在温度为8 ℃ CO2体积分数为6%的气调箱内,用N2调节O2体积分数为2%、4%、6%、8%和10%。每隔2 d检测一次番茄品质（质量损失率、色差L*值、TSS、TA及主观评价）之后对6个评价指标进行标准化处理,采用主成分分析法建立得分函数,并用传统感官评价验证得分模型。试验研究表明：4% O2+6% CO2气调环境下番茄各项指标可以维持较好的水平。综合函数评价得分显示在长期气调保鲜过程中,低氧环境有利于番茄保持较高品质。传统感官评价方式与综合函数有一致性。主成分分析法表明4% O2+6% CO2的气调环境下具有较高的得分水平,可以显著维持保鲜过程中番茄的营养价值,并延长气调保鲜周期。     

Nutrient composition of tomato products prepared using tomato grown under sodic condition with gypsum and farmyard manure treatment

BACKGROUND: The use of sodic water for crop irrigation decreases the availability of nutrients such as nitrogen, calcium, magnesium and zinc to plants and harms crop yield and quality. Crops irrigated with sodic water have been utilised in various product formulations. Gypsum and farmyard manure (FYM) are known to provide good soil amendment under sodic water irrigation. This research was therefore conducted to study the variation in nutrient composition of tomato products prepared from tomatoes irrigated with canal water (control) and those irrigated with sodic water treated with gypsum and FYM at two levels, i.e. 50% neutralisation of sodicity (G₁F₂) and complete neutralisation of sodicity (G₂F₂). RESULTS: The contents of protein, fat, crude fibre, ash, carbohydrate and total soluble sugars in three types of tomato product were in the ranges 1.08–1.68, 0.20–0.31, 0.43–1.07, 0.83–1.06, 6.17–7.22 and 2.32–4.81 g kg^?1 respectively. Tomato products prepared from tomatoes irrigated with G₁F₂‐treated water contained significantly (P < 0.05) less protein, fat, crude fibre, dietary fibre, calcium, magnesium, phosphorus, potassium, iron, zinc and sulfate but more ash, carbohydrate, total soluble sugars, oxalic acid, polyphenols, sodium, chloride and bicarbonate than those prepared from tomatoes irrigated with canal water and G₂F₂‐treated water. CONCLUSION: The results showed that tomato crops irrigated with sodic water treated with gypsum and FYM to varying extent were effective in maintaining and improving the nutrient composition of various tomato products. Copyright © 2009 Society of Chemical Industry     

樱桃番茄渗透预处理热风干燥特性研究

为了提高干制品的营养保留率和品质,进行了渗透预处理联合热风干燥的工艺路线的实验研究。以樱桃番茄为例,分别对不同浓度(50%,70%)蔗糖溶液常压渗透以及真空渗透处理后热风干燥的干燥时间、干燥速率、样品体积比、Vc保留率、硬度、颜色等参数分别进行测定和比较。结果表明:渗透预处理可以除去新鲜樱桃番茄中的大部分自由水,从而减少其热风干燥时间,使产品在高温中的暴露时间减少,从而缩短整体干制时间、提高干制效率及营养品质。经渗透预处理的樱桃番茄干制产品的体积比和Vc保留率要比直接热风干燥的产品增加,而硬度大大下降;其中经浓度为50蔗糖溶液真空渗透预处理后干燥产品的体积比、Vc保留率以及硬度是直接70℃热风干燥的1.72、2.26和0.12倍;而且产品的色泽更加接近新鲜原料,使产品的口感和感官品质更好。研究表明,渗透预处理联合热风干燥是1种很有发展前景的制干工艺。