Umami flavour as a means of regulating food intake and improving nutrition and health

Glutamate production from aerial nitrogen using the nitrogen-fixing bacterium Klebsiella oxytoca

Glutamate is an essential biological compound produced for various therapeutic and nutritional applications. The current glutamate production process requires a large amount of ammonium, which is generated through the energy-consuming and CO2-emitting Haber-Bosch process; therefore, the development of bio-economical glutamate production processes is required. We herein developed a strategy for glutamate production from aerial nitrogen using the nitrogen-fixing bacterium Klebsiella oxytoca. We showed that a simultaneous supply of glucose and citrate as carbon sources enhanced the nitrogenase activity of K. oxytoca. In the presence of glucose and citrate, K. oxytoca strain that was genetically engineered to increase the supply of 2-oxoglutarate, a precursor of glutamate synthesis, produced glutamate extracellularly more than 1 g L-1 from aerial nitrogen. This strategy offers a sustainable and eco-friendly manufacturing process to produce various nitrogen-containing compounds using aerial nitrogen.

Effect of Myrtus communis L. Plant Extract as a Milk Supplement on the Performance, Selected Blood Parameters and Immune Response of Holstein Calves

This research aimed to understand the effects of adding myrtle plant extract obtained from its leaves (MPEL) and roots (MPER) to the milk fed to suckling female Holstein calves, focusing on performance, reproduction, selected blood parameters and immune response. The 50 Holstein female calves, one week of age, were divided into five groups: one group received no plant extract (Control), while the others were supplemented with myrtle plant extracts at doses of 25 mL/day leaf extract (MPEL-25), 25 mL/day root extract (MPER-25), 50 mL/day leaf extract (MPEL-50) and 50 mL/day root extract (MPER-50) for each calf in each treatment group. The extracts were given along with the milk to the experimental groups for 60 days, and for an additional 12 days post-weaning. The results reveal that the feed consumption and live weights increased significantly. Significantly higher leukocyte counts were observed in the 50 mL/head × day myrtle groups, and a higher IgG concentration was also noted in the MPER-50 group compared to the other groups. The serum non-esterified fatty acid (NEFA) concentration significantly decreased in the MPEL-50 and MPER-50 groups, whereas the betahyrdoxy butyric acid (BHBA) concentration increased and the serum glucose concentration significantly decreased with myrtle supplementation. In conclusion, it was determined that the performance, immune system and negative energy balance compensation of female Holstein calves were positively affected by administering extracts obtained from the leaves and roots of the Myrtus communis L. plant at dose levels of 25 and 50 mL/head × day for 72 days, without causing any side effects.

The effect of high-polyphenol sumac (Rhus coriaria) on food intake using sensory and appetite analysis in younger and older adults: A randomized controlled trial

Aging is accompanied by a decline in appetite and food intake with associated deficiencies in both macronutrients and micronutrients. The aim of this study was to investigate the impact of adding Iranian brown sumac (Rhus coriaria) (CIBS) into butternut squash soup on sensory evaluation and food intake among older adults (n = 20; >65 years old) and younger adults (n = 20; 18-35 years old). To evaluate the polyphenol content and antioxidant activity of the sumac samples, a Folin-Ciocalteu assay (FCR) and ferric ion reducing antioxidant power (FRAP) assay were used, respectively. L-glutamic acid was assessed using a Megazyme L-glutamic acid assay. Compusense software was used to assess the sensory evaluation attributes of free-living older adults and younger adults receiving different doses of sumac in butternut squash soup. Nutritics software was used to assess food intake following the addition of 0.37 g of sumac to soup. CIBS was selected based on a preliminary assessment in vitro for L-glutamic acid, antioxidant, and polyphenol content of six varieties of sumac. Sensory evaluation results revealed that the difference in perceived intensity of brown color between the soup samples with different doses of CIBS was greater in the younger adults' group (p = .001) than in older adults (p = .037). In addition, the food intake study found that during the ad libitum lunch, older adults consumed more energy (kcal; p = .014), protein (g; p = .025), carbohydrate (g; p = .013), and fat (g; p = .002) after soup with sumac compared to control soup. The overall findings of this study suggest that the addition of sumac to food may have a potential benefit in enhancing ad libitum lunch intake in older adults leading to effective management of malnutrition. This may promote healthy aging and minimize the burden and the consequences of anorexia of aging as main public health concerns.

Advances in the Potential Application of 3D Food Printing to Enhance Elderly Nutritional Dietary Intake

The contradiction between the growing demand from consumers for "nutrition & personalized" food and traditional industrialized food production has consistently been a problem in the elderly diet that researchers face and discuss. Three-dimensional (3D) food printing could potentially offer a solution to this problem. This article reviews the recent research on 3D food printing, mainly including the use of different sources of protein to improve the performance of food ink printing, high internal phase emulsion or oleogels as a fat replacement and nutrition delivery system, and functional active ingredients and the nutrition delivery system. In our opinion, 3D food printing is crucial for improving the appetite and dietary intake of the elderly. The critical obstacles of 3D-printed food for the elderly regarding energy supplements, nutrition balance, and even the customization of the recipe in a meal are discussed in this paper. By combining big data and artificial intelligence technology with 3D food printing, comprehensive, personalized, and customized geriatric foods, according to the individual traits of each elderly consumer, will be realized via food raw materials-appearance-processing methods. This article provides a theoretical basis and development direction for future 3D food printing for the elderly.

The flavor-enhancing action of glutamate and its mechanism involving the notion of kokumi

The sodium salt of glutamic acid, or monosodium glutamate (MSG), has two effects in foods: one is to induce a unique taste called umami, which is one of the five basic tastes, and the other is to make food palatable (i.e., flavor-enhancing or seasoning effects). However, the mechanism behind how MSG makes food more palatable remains poorly understood, although many food scientists seem to believe that the umami taste itself plays an important role. Here, we propose an alternative notion regarding this topic based on previous and recent studies. When added to complex food compositions, MSG facilitates the binding of existing kokumi substances to kokumi receptors. In turn, these bound kokumi substances enhance the intensity of umami, sweet, salty, and fatty tastes, resulting in increased palatability accompanied by kokumi flavor, such as thickness, mouthfulness, and continuity. The requisite for sufficient palatability and kokumi flavor is a good balance of umami and kokumi substances. This framework gives a scientifically useful background for providing newly developed foods, including cultured meat and plant-based meat substitutes, with good taste characteristics.

Umami taste as a driver for sustainable eating

In the present article it is proposed that a focus on taste is instrumental for promoting a green transition towards a more sustainable eating behaviour involving a more plant-based diet. In particular, it is pointed out that umami is a key driver for this transition because on the one side green food like vegetables typically lack this basic taste that humans on the other side are genetically primed to crave by evolution. We highlight how a mechanism of synergy operates and can be applied to enhance umami taste by a combination of free amino acids and free nucleotides in the same food item either by culinary preparation or by appropriate food pairing. Examples of the power of umami synergy are given, with some focus on sustainable marine foods like bivalves and cephalopods as well as vegetables. Finally, we demonstrate how umami taste as a driver for sustainable eating can be brought to work in the context of communication to children as well as the general public, e.g., by gamification.

Potential hazards associated with the consumption of Scombridae fish: Infection and toxicity from raw material and processing

Scombridae fish (tuna, bonito, and mackerel) have significant ecological and economic values. They are very appreciated by consumers worldwide for their high-quality flesh and for their high nutritional value. However, consumption of Scombridae fish is potentially hazardous. Indeed, several cases of infections and toxicity linked to the consumption of Scombridae fish as raw, or processed food products have been reported worldwide. In this review, we presented the most common health risks associated with Scombridae fish consumption. Diseases associated with the consumption of these fish are generally infectious or toxic and are caused by biological hazards such as bacteria, viruses, parasites, or chemicals hazards that enter the body through contaminated fish (Polycyclic Aromatic Hydrocarbons, histamine) or by physical contaminants such as heavy metals. The risks of contamination exist throughout the food chain, from primary production to the preparation of products for consumption.

Enhancement of sensory and nutritional quality of Sel-roti by the incorporation of soy flour

Sel-roti is a doughnut-like deep-fat fried, puffed, spongy, ring-shaped, and fermented rice-flour confectionary indigenous to Nepal. This study was aimed to enhance the sensory and nutritional quality of Sel-roti by incorporating soy flour. The best product was selected by a series of sensory evaluations, and the nutritional quality was then compared with the control. Sel-roti prepared by incorporating 10% of roasted soybean flour (RSF) had significantly superior (p < .05) sensory perceptions viz. color and appearance, texture, flavor, taste, and overall acceptance among the studied samples. The moisture, crude fat, crude protein, total ash, crude fiber, iron, calcium, and energy content in the best product were significantly increased (p < .05) by the incorporation of 10% RSF. However, total carbohydrates was significantly reduced (p < .05) at 10% RSF incorporation. The results can be used by food processors to formulate a batter for the production of Sel-roti with enhanced sensory and nutritional properties.

Gastronomy unravelled by physics: Gastrophysics

Useful attempts to shed light on the nature of gastronomy from a scientific point of view and to unravel the crucial connection between food, eating and well-being are currently underrepresented in the scientific literature. However, several scientific disciplines ranging from the natural to the social sciences offer valuable new perspectives on gastronomy. As one of the key disciplines in natural science, physics offers original and rigorous perspectives on all processes and structures constrained by the laws of nature. The emerging discipline called gastrophysics employs the full range of concepts, techniques and methods from physics to generate useful scientific input to the complex and holistic reflections on gastronomy. Relying on a review of the existing literature, this article illustrates how a science-based gastrophysics emerges, to a large extent from the convoluted history of food science as well as from various recent ‐ and often overlapping ‐ attempts to combine modern scientific methodology to questions from gastronomy. However, the present review also insists on a physics-inspired methodology to handle scale and complexity in food preparation and consumption across length scales from sub-molecular to entire foods. We exemplify how gastrophysics directly helps to develop gastronomy and how it adds to current approaches in traditional food science. We also suggest that gastrophysics may prove relevant in the context of the ongoing food transformation, which focuses strongly on sustainability, but where the importance of gastronomic aspects in this transformation is greatly needed.

No effect of monosodium glutamate on subjective appetite and subsequent energy intake in children of different ethnicities

Studies have shown that monosodium glutamate (MSG) can enhance satiety and reduce appetite among infants and adults. In a multi-ethnic country such as Malaysia, it is also important to consider whether ethnic variations will influence the effects of MSG on appetite regulation. Thus, this crossover study aimed to investigate the effects of MSG on the subjective appetite and subsequent energy intake among Malaysian children from the three major ethnic groups, namely the Malays, Chinese and Indians. A total of 92 participants aged 9-11 years from the three ethnic groups were recruited for this study. A cup of low-energy vegetable preload soup (100g, with MSG or without MSG) was served to each of the participants on the day of the study, followed by an ad libitum meal 45 min later. Appetite ratings of hunger, fullness, desire to eat and desire to snack were recorded using visual analogue scale (VAS) before the preload, after the preload, before the ad libitum meal and after the ad libitum meal. Results showed that the subjective appetite of the children did not differ between preload conditions (MSG+ or MSG-) throughout the study. Malay, Chinese and Indian children had similar total energy intake during the subsequent meal after the consumption of preload soups. In conclusion, the addition of MSG to low energy preload neither influenced the perception of appetite nor total energy intake in a subsequent ad libitum meal among children. No difference attributable to the participants' ethnicity was observed. Future studies should be conducted to examine whether repeated ingestion of MSG-containing protein-rich preload has potential longer-term effects on appetite and subsequent meal intakes among children from different ethnicities.

The potential role of secondary metabolites in modulating the flavor and taste of the meat

Flavor is one of the most significant characteristics of beef palatability and it can eventually affect the consumer's acceptance of a beef product and purchasing habits. Variation in beef quality is large and is due to many factors, such as differences in genetic background, sex, age, management and nutrition. The consumer's decision to purchase beef is guided by the perception of healthiness and a variety of sensory traits including color, tenderness, juiciness, and aroma or flavor. Apart from this, there are several factors including peptides, fatty acids, amino acids, vitamins, fat contents are also play a vital role in determining the taste and flavor of the meat. In this review, we try to explore and explain the potential role of these factors in modulating the flavor and taste of the meat in detail.

Simultaneous quantification by HPLC of purines in umami soup stock and evaluation of their effects on extracellular and intracellular purine metabolism

Ribonucleotide flavor enhancers such as inosine monophosphate (IMP) and guanosine monophosphate (GMP) provide umami taste, similarly to glutamine. Japanese cuisine frequently uses soup stocks containing these nucleotides to enhance umami. We quantified 18 types of purines (nucleotides, nucleosides, and purine bases) in three soup stocks (chicken, consommé, and dried bonito soup). IMP was the most abundant purine in all umami soup stocks, followed by hypoxanthine, inosine, and GMP. The IMP content of dried bonito soup was the highest of the three soup stocks. We also evaluated the effects of these purines on extracellular and intracellular purine metabolism in HepG2 cells after adding each umami soup stock to the cells. An increase in inosine and hypoxanthine was evident 1 h and 4 h after soup stock addition, and a low amount of xanthine and guanosine was observed in the extracellular medium. The addition of chicken soup stock resulted in increased intracellular and extracellular levels of uric acid and guanosine. Purine metabolism may be affected by ingredients present in soups.

Influence of cancer and acute inflammatory disease on taste perception: a clinical pilot study

Purpose

Cancer patients are at high risk of malnutrition and tumor cachexia further increasing morbidity and mortality. Reasons for cachexia are not clear yet, but inflammatory processes as well as the occurrence of taste disorders reducing nutrient uptake are discussed to play key roles. The purpose of this study was to gain insight into causative factors of taste disturbance in cancer patients. Does the cancer itself, inflammatory processes or cancer therapy influence taste disorders?

Methods

To capture an underlying taste disorder patients with cancer (n = 42), acutely hospitalized inflammatory disease patients (n = 57) and healthy controls (n = 39) were examined. To assess the influence of chemotherapy, patients with and without chemotherapy were compared. Taste tests were performed according to DIN ISO 3972:2011. Inflammation was recorded using laboratory parameters. Statistical evaluation was conducted using the Software R.

Results

Cancer patients showed significantly increased taste thresholds for sweet, salty, and umami compared to healthy controls. There were no significant differences in taste detection and recognition between patients with former, current, or without chemotherapeutical treatment. Patients with an acute inflammatory disease showed an increased taste threshold for umami compared to healthy controls.

Conclusions

It could be shown that cancer patients suffer from taste disorders irrespective of an existing chemotherapeutical treatment. Cancer-related inflammation appears to have a greater impact on taste perception than an acute inflammatory process. Therefore, an adapted dietary adjustment should be carried out at an early stage for cancer patients in order to avoid nutritional disorders caused by a taste disorder.

Value: Changes in the Detection and Recognition Thresholds of Three Basic Tastes in Lung Cancer Patients Receiving Cisplatin and Paclitaxel and Its Association with Nutritional and Quality of Life Parameters

We evaluated the effects of cisplatin and paclitaxel on taste acuity and their associations with nutritional and health-related quality of life (HRQL) in patients with advanced non-small-cell lung cancer (NSCLC). Forty chemotherapy (CT)-naïve patients were assessed at baseline and after two cycles of paclitaxel and cisplatin. The taste evaluation was performed using a rinsing technique to identify detection and recognition thresholds (DT and RT) of bitter, sweet, and umami tastes. At baseline, 37.5% of the patients reported dysgeusia. After CT, the patients showed lower medians DT (p = 0.017) and RT (p = 0.028) for umami taste. These decreases were associated with clinical neuropathy, worse HRQL, and a tendency toward increased appetite loss. Additionally, CT did not significantly reduce the median DT for sweet (p = 0.09), which is associated with lower intake of protein (p = 0.015), animal protein (p = 0.010), fat (p = 0.004), and iron (p = 0.047). CT decreased the median DT for bitter (p = 0.035); however, this decrease was not associated with nutritional parameters or with HRQL. Sensitivity to taste increased with paclitaxel and cisplatin CT, making foods more unpleasant, and it was associated with neuropathy, worse HRQL, and reduced nutrient intake in advanced NSCLC patients. The protocol was registered at clinicaltrials.gov (NCT01540045).

Collecting, comparing, and computing sequences: the making of Margaret O. Dayhoff's Atlas of Protein Sequence and Structure, 1954-1965

Collecting, comparing, and computing molecular sequences are among the most prevalent practices in contemporary biological research. They represent a specific way of producing knowledge. This paper explores the historical development of these practices, focusing on the work of Margaret O. Dayhoff, Richard V. Eck, and Robert S. Ledley, who produced the first computer-based collection of protein sequences, published in book format in 1965 as the Atlas of Protein Sequence and Structure. While these practices are generally associated with the rise of molecular evolution in the 1960s, this paper shows that they grew out of research agendas from the previous decade, including the biochemical investigation of the relations between the structures and function of proteins and the theoretical attempt to decipher the genetic code. It also shows how computers became essential for the handling and analysis of sequence data. Finally, this paper reflects on the relationships between experimenting and collecting as two distinct "ways of knowing" that were essential for the transformation of the life sciences in the twentieth century.