Nutrition and chemosensory perception in the elderly

The elderly person's perception of foods and food flavor is affected by age‐associated changes in the chemical senses (taste, smell, and trigeminal sensation). Both classic and modern psychophysical techniques have been applied to achieve some understanding of these changes.

Taste threshold sensitivity declines with age; however, the magnitude of the decline and the degree to which taste qualities are differentially affected remains to be understood. Suprathreshold taste intensity perception is affected by age, but there is a differential effect of taste quality.

Experiments with blended foods have indicated that both olfactory and taste deficits contribute to older people's difficulty with food identification. Experiments assessing threshold sensitivity, suprathreshold intensity, and suprathreshold identification have all demonstrated significant impairment in olfaction in old age. In fact, these effects are far greater than in the taste system.

Patients with Alzheimer's disease show even greater olfactory deficits than normal elderly and the effect is related to the degree of dementia. We have ruled out nasal disease in these patients as the primary causes of olfactory insensitivity, because significant impairment remains when the influence of nasal airflow and nasal cytology has been removed statistically. Both normal elderly and patients with Alzheimer's disease show impairment in odor memory. Sensitivity to, familiarity with, and identifiability of the odors all play a role in odor memory performance.

Flavor preference also changes over the lifespan. Older subjects, for instance, rate high concentration of sugar and salt as pleasanter than young subjects do. Multiple influences contribute to this phenomenon. Elderly persons and those of lower nutritional status have shown preferences for higher concentrations of casein hydrolysate than young persons and those of higher nutritional status, suggesting that dietary preference can be related to chemosensory cues.

There are significant age‐associated changes in chemosensory perception that have the potential to interact with dietary selection and nutrition in the elderly. A better understanding of these phenomena may promote health and well‐being in the elderly.     

Toward predictive food process models: A protocol for parameter estimation

Mathematical models, in particular, physics-based models, are essential tools to food product and process design, optimization and control.

The success of mathematical models relies on their predictive capabilities. However, describing physical, chemical and biological changes in food processing requires the values of some, typically unknown, parameters. Therefore, parameter estimation from experimental data is critical to achieving desired model predictive properties.

This work takes a new look into the parameter estimation (or identification) problem in food process modeling. First, we examine common pitfalls such as lack of identifiability and multimodality. Second, we present the theoretical background of a parameter identification protocol intended to deal with those challenges. And, to finish, we illustrate the performance of the proposed protocol with an example related to the thermal processing of packaged foods.     

How dietary intake has been assessed in African countries? A systematic review

Background: Dietary patterns are often considered as one of the main causes of non-communicable diseases worldwide. It is of utmost importance to study dietary habits in developing countries since this work is scarce.

Objective: To summarize the most recent research conducted in this field in African countries, namely the most used methodologies and tools.

Methods: A systematic review was conducted on MEDLINE®/PubMed, aiming to identify scientific publications focused on studies of dietary intake of different African populations, in a ten-year period. Papers not written in English/Portuguese/Spanish, studies developed among African people but not developed in African countries, studies aiming to assess a particular nutrient/specific food/food toxin and studies that assessed dietary intake among children were excluded.

Findings: Out of 99 included studies, the 24-hour recall and the food-frequency questionnaire were the most used dietary intake assessment tools, used to assess diet at an individual level. It was also observed that often country-unspecific food composition databases are used, and the methodologies employed are poorly validated and standardized.

Conclusions: There is an emergent need to improve the existing food databases by updating food data and to develop suitable country-specific databases for those that do not have their own food composition table.     

Histamine food poisonings: A systematic review and meta-analysis

Objective: The aim of this study was to assess the mean of histamine concentration in food poisoning.

Design: Systematic review and meta-analysis of reports published between 1959 and 2013.

Study selection: Main criteria for inclusion of studies were: all report types that present outbreaks of “histamine poisoning' or “scombroid syndrome” from food, including histamine content and type of food. Health status of people involved must be nonpathological.

Results: Fifty-five (55) reports were included, these studies reported 103 incidents. All pooled analyses were based on random effect model; histamine mean concentration in poisoning samples was 1107.21 mg/kg with confidence interval for the meta-mean of 422.62–2900.78 mg/kg; heterogeneity index (I2) was 100% (P < 0.0001); prediction interval was 24.12–50822.78 mg/kg. Fish involved in histamine poisoning was mainly tuna or Istiophoridae species. No clues of association between concomitant conditions (female sex, alcohol consumption, previous medication, and consumption of histamine releasing food) and histamine poisoning, were highlighted.

Conclusions: This is the first systematic review and meta-analysis that analyzes all the available data on histamine poisoning outbreaks evaluating the histamine concentration in food involved. Histamine mean concentration in poisoning samples was fairly high. Our study suffers from some limitations, which are intrinsic of the studies included, for instance the lack of a complete anamnesis of each poisoning episode.

Protocol registration: Methods were specified in advance and have been published as a protocol in PROSPERO database (18/07/2012 -CRD42012002566).     

Taste loss in the elderly: Possible implications for dietary habits

Aging may coincide with a declining gustatory function that can affect dietary intake and ultimately have negative health consequences. Taste loss is caused by physiological changes and worsened by events often associated with aging, such as polypharmacy and chronic disease. The most pronounced increase in elderly people's detection threshold has been observed for sour and bitter tastes, but their perception of salty, sweet, and umami tastes also seems to decline with age. It has often been suggested that elderly people who lose their sense of taste may eat less food or choose stronger flavors, but the literature has revealed a more complicated picture: taste loss does not appear to make elderly people prefer stronger flavors, but nutrition surveys have pointed to a greater consumption of sweet and salty foods.

Real-life eating habits thus seem to be more influenced by other, social and psychological factors. Elderly gustatory function is worth investigating to identify dietary strategies that can prevent the consequences of unhealthy eating habits in the elderly.

This paper discusses age-related changes in taste perception, focusing on their consequences on food preferences, and pointing to some strategies for preserving appropriate dietary habits in elderly people.     

Dietary fiber,inulin, and oligofructose: A review comparing their physiological effects

Dietary fiber is a general terra. It covers a wide variety of substances that belong to the family of carbohydrates that resist hydrolysis by human alimentary enzymes but are fermented by colonie microflora.

The main physiological effects of dietary fiber are primarily on gastric emptying and small intestinal transit time, resulting in an improved glucose tolerance and a decreased digestion of starch; second, on colonie transit time and large bowel functions due to fermentation by ceco‐colonic microbial flora or bulking action.

The so‐called soluble dietary fibers are fermented to a large extent by a wide variety of anaerobic bacteria that result in an increase in bacterial biomass, an increase in fecal mass, a change in intracolonic pH, and production of short chain fatty acids and various gases as metabolic end products. The insoluble fibers are only marginally fermented; they serve almost exclusively as bulking agents that result in shorter transit time and increased fecal mass.

The short chain fatty acids resulting from the colonie fermentation of dietary fiber are largely absorbed via the portal blood and reach both the liver and the peripheral tissues. They induce changes in glucose and fat metabolism leading to post‐prandial hypoglycemia and long‐term hypolipidemia.

Inulin and oligofructose are fructans with a degree of polymerization of 2 to 60 and 2 to 20. respectively. Due to the structural conformation of their osidic bridge ((3 2–1), they both resist the hydrolysis by human alimentary enzymes. Moreover, when reaching the colon, both inulin and oligofructose are almost quantitatively fermented almost exclusively by colonie bifidobacteria and bacteroides. Such an extensive fermentation causes an increase in fecal bacterial biomass, a decrease in ceco‐colonic pH. and produces a large amount of fermentation products among which the short chain fatty acids that exert systemic effects on lipid metabolism.

Thus, both inulin and oligofructose have most of the characteristics of a dietary fiber and the proposal is made to classify them as such. Moreover, they are bifidogenic factors, because, due to still unknown reasons, they are primarily fermented by bifidobacteria.

It is concluded from this review that “nondigestible fructooligosaccharides.” even though they arc not included in the carbohydrate fraction that is quantified as dietary fiber by classic analytical methods, have most of the physiological effects of a dietary fiber. Because it has become necessary for the consumer to be informed clearly and specifically on the nature and the beneficial effects of all fermentable carbohydrates that will “feed” their colon, it is suggested that food labeling should be extended to include such products in the dietary liber fraction.     

A critical review on hepatoprotective effects of bioactive food components

Background: Bioactive food components are nonessential biomolecules, which help to give beneficial effects to human being against several diseases. Natural bioactive food components derived from plants and animals, such as phytosterols, carotenoids, polyphenols and fatty acids, have been proposed as valuable substitutions for anticipation and management of hepatotoxic effects and its chronic complications based on in vitro and in vivo studies.

Objectives of the study: To summarize drugs and chemical-induced hepatotoxicity and review how various bioactive food components attenuate the hepatotoxicity via cellular mechanisms.

Results: Remarkable studies demonstrated that the health promoting effects of bioactive components originated from plants have been frequently attributed to their antioxidant properties and facilitate to increase cellular antioxidant defense system and thereby scavenge free radicals, inhibit lipid peroxidation, augment anti-inflammatory potential, and further protect the liver from damage.

Conclusion: In this critical review, we summarize current progress in clarifying the molecular mechanism in hepatotoxicity and curative potential of the bioactive food components and its successive clinical outcomes in the field of drug discovery and overcome the problems of medication and chemical-induced hepatotoxic effects.     

On the presence of Inulin and Oligofructose as natural ingredients in the western diet

The classic definitions of inulin and oligofructose are constructively criticized. It is observed that inulin cannot unequivocally be described as a polydisperse 1‐kestose‐based (GF_n) β(2 ? 1) linear fructan chain, but that inulin always contains small amounts of F_m and branched molecules. This review article describes the presence of inulin and oligofructose in common foodstuffs. Historical data on human consumption add an extra dimension.

Modern analytical techniques (HPLC, LGC, HPAEC‐PAD) are used to check the variety of data mentioned in the literature throughout the past century. Methods to determine inulin and oligofructose in natural foodstuffs (cereals, fruit, and vegetables) are optimized and used to determine the loss of inulin during storage and during preparation of the food.

These findings allow quantification of the amount of inulin and oligofructose in the average daily western diet. The daily per capita intake is estimated to range from 1 to 10 g, depending on geographic, demographic, and other related parameters (age, sex, season, etc.).

Inulin and oligofructose are not measured by classic methods of dietary fiber analysis and consequently are often not mentioned in food tables. Their significant contribution (1 to 10 g/d/per capita) to the dietary fiber fraction (recommended at 25 g/d/per capita) is not taken into account in any nutritional recommendations. In view of this, inulin and oligofructose deserve more attention, both in food composition tables and in diet or nutrition studies.     

Triacylglycerols Determination by High-temperature Gas Chromatography in the Analysis of Vegetable Oils and Foods: A Review of the Past 10 Years

The analysis of triacylglycerols by high-temperature gas chromatography, along the last 10 years has been reviewed in this paper. The interest in this topic has grown along the last years due to the triacylglycerols are the main components of oils and fats and they are being used for the characterization and authentication of foods products.

The most commonly used procedures, including the official methodologies, applying high-temperature gas chromatographic techniques are shown. Their importance in the characterization of different kind of samples, vegetable oils, seeds, dairy products, etc., is considered.

This review is not intended to be a comprehensive dissertation on the field of triacylglycerols analysis since that would require sufficient space to occupy a book in its own right. Rather, it will outline selected considerations and developments, where the technique has been applied.     

Physiological protection of probiotic microcapsules by coatings

Nowadays, food and nutrition have a greater impact in people's concerns, with the awareness that nutrition have a direct impact in health and wellbeing. Probiotics have an important role in this topic and consumers are starting to really understand their potential in health, leading to an increasing interest of the companies to their commercial use in foods. However, there are several limitations to the use of probiotics in foods and beverages, being one of them their efficiency (directly associated to their survival rate) upon ingestion.

This work is focused in microencapsulation techniques that have been used to increase probiotics efficiency. More specifically, this work reviews the most recent and relevant research about the production and coating techniques of probiotic-loaded microcapsules, providing an insight in the effect of these coatings in probiotics survival during the gastrointestinal phase.

This review shows that coatings with the better performances in probiotics protection, against the harsh conditions of digestion, are chitosan, alginate, poly-L-lysine, and whey protein. Chitosan presented an interesting performance in probiotics protection being able to maintain the initial concentration of viable probiotics during a digestive test. The analyses of different works also showed that the utilization of several coatings does not guarantee a better protection in comparison with monocoated microcapsules.     

Critical assessment of the epidemiological data concerning the impact of antioxidant nutrients on cancer and cardiovascular disease

Epidemiological studies strongly suggest that high intakes of foods rich in beta carotene, as well as those rich in vitamin E or vitamin C, reduce the risk of some but not all cancers and cardiovascular disease. It is difficult to determine whether these antioxidant nutrients per se are the sole protective agents or whether other factors associated with foods containing them contribute to the foods’ protective effects.

With respect to vitamin E, a number of studies where dietary and supplementary vitamin E were clearly differentiated, a reduced risk of certain cancers or cardiovascular disease from supplemental vitamin E but not from dietary vitamin E was demonstrated. This provides strong presumptive evidence that high intakes of vitamin E per se provide a health benefit.

Only a few intervention studies with specific nutrients are available and results are inconsistent.     

Dietary fruits and vegetables and cardiovascular diseases risk

Diet is likely to be an important determinant of cardiovascular disease (CVD) risk. In this article, we will review the evidence linking the consumption of fruit and vegetables and CVD risk.

The initial evidence that fruit and vegetable consumption has a protective effect against CVD came from observational studies. However, uncertainty remains about the magnitude of the benefit of fruit and vegetable intake on the occurrence of CVD and whether the optimal intake is five portions or greater. Results from randomized controlled trials do not show conclusively that fruit and vegetable intake protects against CVD, in part because the dietary interventions have been of limited intensity to enable optimal analysis of their putative effects.

The protective mechanisms of fruit and vegetables may not only include some of the known bioactive nutrient effects dependent on their antioxidant, anti-inflammatory, and electrolyte properties, but also include their functional properties, such as low glycemic load and energy density. Taken together, the totality of the evidence accumulated so far does appear to support the notion that increased intake of fruits and vegetables may reduce cardiovascular risk. It is clear that fruit and vegetables should be eaten as part of a balanced diet, as a source of vitamins, fiber, minerals, and phytochemicals.

The evidence now suggests that a complicated set of several nutrients may interact with genetic factors to influence CVD risk. Therefore, it may be more important to focus on whole foods and dietary patterns rather than individual nutrients to successfully impact on CVD risk reduction.

A clearer understanding of the relationship between fruit and vegetable intake and cardiovascular risk would provide health professionals with significant information in terms of public health and clinical practice.     

On modeling changes in food and biosolids at and around their glass transition temperature range

Temperature‐induced mechanical and other changes in biosolids are regulated by three types of kinetics, depending on whether the material is in the glassy state, undergoing a transition, or fully plasticized. The transition itself can take place over a considerable temperature range, which in many food and biological systems happens to be the most pertinent to their functionality and stability. At the transition onset, the plot of stiffness vs. temperature has a downward concavity. It is reversed only at an advanced stage of plasticization after much of the stiffness has already been lost. Consequently, the WLF, Arrhenius, or any other model that implies a continuous upward concavity cannot account for changes in the transition region, and it is unsafe to use them to predict properties through extrapolation.

The mechanical changes in the transition region can be described by a model with the mathematical structure of Fermi's function. Its applicability has been demonstrated with published data on a variety of foods and biosolids. Because the plot of stiffness vs. moisture, or water activity, has the same general shape as that of the stiffness vs. temperature plot, it too can be described by a model with the same mathematical format.

Because moisture lowers the transition center temperature in a manner that can be described by a simple algebraic expression, the combined effects of temperature and moisture can be incorporated into a single general model. The latter can be used to create three‐dimensional displays of the stiffness‐temperature‐moisture characteristic relationships of biosolids at and around their transition. At temperatures well above that of the transition, though, where a plot of log stiffness vs. temperature has a clear upper concavity, this model is no longer applicable, and the changes are better described by the WLF or an alternative model.     

Determination of diffusion and partition coefficients of model migrants by direct contact and vapour phase transfer from low-density polyethylene films into cake

The aim of the present study was to determine the migration kinetics of one photoinitiator, benzophenone, and two optical brighteners, Uvitex OB and 1,4-diphenyl-1,3-butadiene (DPBD), from low-density polyethylene (LDPE) films into cake. Transfer was assessed by both direct contact and also the vapour phase.

To perform the migration tests by direct contact, plastic films enriched with the additives were placed between two cake slices. To evaluate the migration through the gas phase, cake and the fortified LDPE film were placed with no direct contact in a glass container that was hermetically closed. Samples were stored at different time–temperature conditions.

Target compounds were extracted from the films with ethanol (70°C, 24 h) and analysed by HPLC-DAD. Relevant parameters such as partition and diffusion coefficients between food and plastic film were calculated. The Arrhenius equation was applied to estimate the diffusion coefficient at any temperature.

The data indicate that migration of benzophenone occurs in a significant extent into cake by both direct contact and through the gas phase (no direct contact). Conversely, very little migration occurred for Uvitex OB by direct contact and none through the gas phase. Results for benzophenone suggest that migration through the gas phase should be considered when evaluating migration from food packaging materials into food.     

Vitamin D Bioavailability: State of the Art

There has been renewed interest in vitamin D since numerous recent studies have suggested that besides its well-established roles in bone metabolism and immunity, vitamin D status is inversely associated with the incidence of several diseases, e.g., cancers, cardio-vascular diseases, and neurodegenerative diseases. Surprisingly, there is very little data on factors that affect absorption of this fat-soluble vitamin, although it is acknowledged that dietary vitamin D could help to fight against the subdeficient vitamin D status that is common in several populations. This review describes the state of the art concerning the fate of vitamin D in the human upper gastrointestinal tract and on the factors assumed to affect its absorption efficiency. The main conclusions are: (i) ergocalciferol (vitamin D₂), the form mostly used in supplements and fortified foods, is apparently absorbed with similar efficiency to cholecalciferol (vitamin D₃, the main dietary form), (ii) 25-hydroxyvitamin D (25OHD), the metabolite produced in the liver, and which can be found in foods, is better absorbed than the nonhydroxy vitamin D forms cholecalciferol and ergocalciferol, (iii) the amount of fat with which vitamin D is ingested does not seem to significantly modify the bioavailability of vitamin D₃, (iv) the food matrix has apparently little effect on vitamin D bioavailability, (v) sucrose polyesters (Olestra) and tetrahydrolipstatin (orlistat) probably diminish vitamin D absorption, and (vi) there is apparently no effect of aging on vitamin D absorption efficiency.

We also find that there is insufficient, or even no data on the following factors suspected of affecting vitamin D bioavailability: (i) effect of type and amount of dietary fiber, (ii) effect of vitamin D status, and (iii) effect of genetic variation in proteins involved in its intestinal absorption.

In conclusion, further studies are needed to improve our knowledge of factors affecting vitamin D absorption efficiency. Clinical studies with labeled vitamin D, e.g., deuterated or ¹³C, are needed to accurately and definitively assess the effect of various factors on its bioavailability.     

The brave new world of FDA nutrition regulation — some thoughts about current trends and long‐term effects∗

This article reviews long‐term trends at the U.S. Food and Drug Administration (FDA) concerning regulation of nutrition, and considers how these trends may affect products of the food industry in the decades ahead. Among the topics discussed are the FDA's rules concerning the provision of basic, standard format nutrition information (“nutrition labeling”) on food products. These rules have changed dramatically over the past 50 years from a period when no information was required to a period when information was required only if a nutrient claim was made or if a nutrient was added to the product to the new FDA regulations that become effective in 1994, which require standardized nutrition labeling on most food products in interstate commerce.

There have also been important shifts in the procedures concerning government regulation of nutrition‐related labeling. In general, previously a food company was free to provide truthful and nonmisleading labeling claims about the nutrition content of a food product, leaving it to FDA to police the market and to take regulatory action against any labeling that the agency deemed either to be false or misleading or to constitute an unauthorized drug claim. In contrast, under new FDA regulations, it will become automatically illegal to use any “health claim” or “nutrient content claim” in food labeling unless the claim has been approved in advance by an FDA regulation.

The author notes that these and other developments reveal, on the one hand, a trend toward requiring more nutrition information on food labels, but, on the other hand, a countervailing trend toward requiring government approval for the making of new nutrition‐related statements and placing greater burdens on industry to justify new types of nutrition‐related statements. Additional trends include the increased pressures on companies to formulate foods to be more healthful and a trend toward giving the FDA more power over the industry.

The article concludes with comments about additional regulatory requirements to which the long‐term trends might lead in future decades.     

State of art of nanotechnology applications in the meat chain: A qualitative synthesis

Background: Nanotechnology is a promising area in industry with a broad range of applications including in the agri-food sector. Several studies have investigated the potential benefits deriving from use of nanomaterials in the context of the whole food chain drawing scenarios of benefits but also potential for concerns. Among the agri-food sector, animal production has potential for nanomaterial application but also for safety concerns due to the possibility of nanomaterial accumulation along the farm-to-fork path.

Scope and Approach: The aim of this work was to define the state of the art of nanomaterial applications in the animal production sector by assessing data belonging to recently publishes studies. To do this, a qualitative synthesis approach was applied to build a fit-for-purpose framework and to summarise relevant themes in the context of effectiveness, feasibility and health concerns.

Key findings and conclusions: Nanomaterials have potential for use in a wide range of applications from feed production and farming to food packaging, including several detection tools designed for the benefit of consumer protection. The current high degree of variability in nanomaterials tested and in study designs impairs external validation of research results. Further research is required to clearly define which safe nanomaterial applications have the potential to reach the market.     

Nutrition of infants and young children (one to three years) and its effect on later health: A systematic review of current recommendations (EarlyNutrition project)

Background. EarlyNutrition (www.project-earlynutrition.eu) is an international research project investigating the effects of early nutrition on metabolic programming.

Objective. To summarize, by performing a systematic review, current standards, recommendations, guidelines, and regulations (hereafter, referred to as documents) on the nutrition of children up to three years of age. Special emphasis was placed on long-term effects of early nutrition, such as the risk of cardiovascular disease, hypertension, overweight, obesity, metabolic syndrome, diabetes, or glucose intolerance.

Methods. MEDLINE, selected databases, and websites were searched for documents published between 2008 and January 2013.

Results. Forty two documents met the inclusion criteria. The strongest and most consistent evidence for a protective, long-term effect was documented for breastfeeding. Also, limiting the intake of sodium and rapidly absorbed carbohydrates, use of a specific meal pattern, reducing the consumption of saturated fatty acids by replacing them with polyunsaturated fatty acids, and lowering the intake of trans fatty acids, seems beneficial. Many documents did not evaluate long-term outcomes of interest to us, or reported insufficient or imprecise data. Inconsistency in recommendations for some outcomes and research gaps were identified.

Conclusions. Our findings may serve as a helpful tool in planning further research, preventive actions against important diet-related diseases, and guidelines improvement.