Search results

This article aims to consider the use of high pressure processing in order to gain functional advantages through proteins structure control. High pressure processing has been used to produce high-quality food with extended shelf life and could also be used to modify foods functionality.

The effect of high pressure on protein structure and functionality is looked at and comparisons are made with heat effect in places. β-lactoglobulin and whey proteins are mainly taken as examples.

A controlled partial protein unfolding through mild high pressure processing could lead to a range of intermediate molecular structures. These are distinct from the native and completely unfolded structure and have been referred to as molten globules. The partly unfolded molecular states, hence, are postulated to have increased functionality and could be interesting for the food industry.

The opportunity and challenges represented by these theoretical elements are discussed. In particular, the effect of protein concentration and aggregation is emphasised.

World shortages of certain raw materials leading to appreciable price increases is currently a regular feature of our daily lives— and is likely to be so, unfortunately, for the next few years. Meat has been increasing in price owing to various shortages in animal feeding stuffs. The fact that the populations of developing countries rightly demand that home produced meat is made available for their home consumption rather than for export is also adding to the problem as far as developed nations are concerned. The obtaining of sufficient protein for everyone's dietary needs is as basic and important as the need to have sufficient supplies of energy to meet world requirements. The amount of protein to be found on this earth is in excess of our projected needs, but there could well be severe shortages of protein foods for humans in an acceptable or usable state, especially if we continue to rely so heavily upon animal protein. There is, therefore, a real and urgent need for scientists to develop ways and means of transforming basic protein raw materials into acceptable products.

The purpose of this paper is to study the utilization of the rice bran protein concentrate (RBPC) in biscuits to upgrade the nutritional quality.

Extraction of rice bran protein concentrate (RBPC) from defatted rice bran was standardized using alkali extraction method. Defatted rice bran and RBPC were analyzed for their proximate composition. RBPC was analyzed for its bulk density, foaming capacity (FC), emulsion activity (EA), and water and oil absorption capacity. RBPC was incorporated in biscuits at 5, 10 and 15 per cent levels. The biscuits were analyzed for their physicochemical, fracture strength (texture analyzer) and sensory attributes (nine‐point hedonic scale) to assess their acceptability.

The maximum yield of 13.2 per cent for RBPC was obtained at alkaline pH of 11, temperature of 60°C and extraction time of 60 minutes. The bulk density, foaming capacity, emulsifying ability, water and oil absorption capacity of RBPC were 0.4 g/ml, 11 per cent, 40 per cent, 2.9 ml/g and 2.3 ml/g respectively. The protein content of biscuits increased significantly from 7.3 per cent in control biscuits to 15.4 per cent in the 15 per cent RBPC supplemented biscuits with their fracture strength also significantly higher than the control biscuits (p<0.05). Replacement of refined wheat flour up to 10 per cent RBPC produced protein‐enriched biscuits with desirable overall acceptability.

Rice bran protein concentrate can be beneficially utilized to formulate protein enriched biscuits with enhanced nutritional value especially for malnourished or undernourished people.

This study identifies new factors influencing the adoption of two recently promoted messages in Canada's updated food guide (FG): enhancing pleasure of eating healthy foods (PEHFs) and shifting food choices towards plant protein foods. Currently, limited and contradictory evidence is available regarding associations between environmental values, nutrition literacy, PEHFs, and plant/animal protein food consumption.

An online survey measuring environmental values; nutrition literacy, distinctively based on previous (2007) and most recent (2019) FG messages; PEHFs; and annual changes in the consumption of protein foods was sent to Quebec residents (N = 128).

Greater nutrition literacy of both 2007 and 2019 FGs and greater environmental values were associated with greater PEHFs (ß = 0.248, p < 0.01; ß = 0.209, p < 0.05; ß = 0.423, p < 0.001, respectively). Greater PEHFs was associated with greater consumption of plant protein foods (ß = 0.405, p < 0.001). Greater nutrition literacy of the 2007 FG was associated with greater consumption of animal protein foods (ß = 0.409, p < 0.001), whereas greater nutrition literacy of the 2019 FG was linked to lower consumption of animal protein foods (ß = −0.225, p < 0.05).

Enhancing PEHFs may require increasing general FG nutrition literacy and strengthening environmental values. To encourage plant protein food consumption and decrease animal protein food consumption, the authors recommend promoting PEHFs and increasing nutrition literacy based on newest FG recommendations.

This new evidence may help develop strategies promoting PEHFs and plant protein food consumption, thus increasing uptake of new FG recommendations.

Background/Objectives: Protein-based meal replacements (MR) with viscous soluble fibre are known aids for weight loss. This study aims to compare the effects of new whey and vegan MR containing different amounts of PGX (PolyGlycopleX) on weight loss over 12 weeks, along with a calorie-restricted diet.

Subjects/Methods: Sixty-eight healthy adults of both sexes (53 women; 15 men; average age 47.1 years; BMI 31 ± 7.1 kg/m² and weight 85.05 ± 23.3 kg) were recruited. Participants consumed a whey or vegan MR twice/d (5–10 g/day PGX) with a low-energy diet (1,200 kcal/day), over 12 weeks. Weight, height, waist and hip circumference were recorded (four time periods).

Results: Forty-four participants completed the study. Results showed significant reductions in average body weight and at week 12, whey group was [−7.7 kg ± 0.9 (8.3%), p < 0.001] and vegan group was [−4.5 kg ± 0.8 (6.2%), p < 0.001)]. All participants (n = 44; BMI 27 to 33 kg/m²) achieved significant reductions in body measurements from baseline to week 12; p < 0.001. Conclusions: Supplementation of protein-based MR with PGX and a balanced, low-energy diet, appears to be an effective approach for short-term weight loss.

As the authors were evaluating if the MR as a whole (i.e. with PGX) caused weight loss from baseline over the 12 weeks, no comparators, i.e. just the MR without PGX, were used. Formulation of these new MRs resulted in a whey product with 5 g PGX and a vegan product with 2.5 g PGX. Only 2.5 g PGX could be formulated with the vegan protein due to taste and viscosity limitations. Study participants were not randomized and no control groups (e.g. no MR or MR without PGX but with energy restricted diet) were used. Furthermore, it is not clear whether the sort of protein alone or the combination with a higher amount of PGX (whey with 5 g PGX/serving vs vegan with 2.5 g PGX/serving) has contributed to these significant greater weight-loss effects. This was something the authors were testing, i.e. could only 2.5 g PGX/serving have an effect on weight loss for a vegan MR. These limitations would be somethings to evaluate in a subsequent randomized controlled study. Hence, the results of this study may serve as a good starting point for further sophisticated randomized controlled trials that can demonstrate causality – which the authors acknowledge as one of the fundamental limitations of an observational study design. Participants tracked their calories but adherence and compliance were self-assessed and they were encouraged to keep their exercise routine consistent throughout the study. Hence, these are further limitations. No control group was used in this study to observe the effect of the dietary intervention and/or physical activity on weight loss alone. However, a goal of the authors was to keep this study as close to a real-life situation as possible, where people would not be doing any of these measurements, to see if with minimal supervision or intervention, people can still lose weight and alter their body composition. Furthermore, differences in gender and the corresponding weight loss effects in response to MR-protein-based treatments could be evaluated in follow-up studies.

This study indicates that the consumption of protein-based (animal, whey or plant, pea protein) MR incorporating the highly soluble viscous PGX is beneficial for weight loss when combined with a healthy-balanced, calorie-restricted diet. MRs at either 2.5 g or 5 g per serving (RealEasy^TM with PGX) proved to be a highly effective as a short-term solution for weight loss. The observed results are encouraging, however, further long-term studies (i.e. randomized clinical trials RCT) are needed to confirm the clinical relevance. RCTs should focus on the individual effects of PGX and/or the different protein sources used in MRs, on weight loss and the maintenance of the reduced body weight, and should measure detailed blood parameters (lipid profiles, glucose etc.) as well as collect detailed exercise and food consumption diaries.

To the authors’ knowledge, this is the first study comparing a whey versus vegan, (as pea) protein-based MR that is supplemented with fibre PGX; thus, this work adds information to the already existing literature on fibre (such as PGX) and MRs regarding their combined weight loss effects. The purpose of this study was to observe if the novel protein-based (either whey or vegan versions) MR RealEasy^TM with PGX at 2.5 or 5 g in addition to a calorie-restricted diet (total of 1,200 kcal/day) would aid in weight loss in individuals over a 12-weeks period. Adding increasing amounts of whey protein and soluble fibre can help reduce subsequent ad libitum energy intake which could help adherence to energy restricted diets, but whether similar effects are seen with vegan protein is unclear – this study does aim to address this.

This study aims to systematically investigate the tribological behaviors of metal and polyethylene using lubricants composed of four synovial fluid (SF) components. In addition, the changes in protein conformation during wear were analyzed to establish the correlation between protein conformation and tribological properties.

A pin-on-disk tester with multidirectional sliding motion was used for tribological properties observation between metal and polyethylene pairs. Simulated SFs with four main constituents were used as the testing lubricants. Differential scanning calorimetry and Raman were used to characterize the changes in protein conformation during wear.

The coupling of lipids and hyaluronic acid further suppressed protein denaturation. The protein structures of the adsorption film and the ensnared protein chains in the friction zone were maintained to a certain extent, thus improving the friction and wear of polyethylene.

These findings established the correlation between protein conformation and friction and wear, promoting the understanding of the lubrication mechanism of artificial joints.

The main purpose of this study is to demonstrate the development of an enzyme-based sensor for haloalkane detection. Haloalkane is a toxic compound that is found as genotoxic impurities in pharmaceutical products and contaminants in waste. The need to investigate the genotoxic level in pharmaceutical manufacturing is very crucial because of its toxicity effects on human health. The potential of mini protein as an alternative bioreceptor was explored with the aim to be more effective and stable under extreme conditions.

Mini proteins of haloalkane dehalogenase (HLD) were computationally designed and experimentally validated. Tapered multimode fiber (TMMF) was bio-functionalized with a bioreceptor either native (positive control) or mini protein. The absorbance-based sensor resulting from the binding interaction of mini protein with haloalkane was monitored through a wavelength range of 200-1,300 nm.

An increment of the UV absorption is observed at 325 nm when haloalkane interacted with the immobilized bioreceptors, native or mini protein. Both biosensors displayed a continuous response over the range of 5-250 µM haloalkane. They also had the capability to detect haloalkanes below 1 min and with an operational stability of up to seven days without significant loss of sensitivity.

The results indicate the potential viability of the enzyme HLD-based sensor to monitor the existence of haloalkane in both pharmaceutical and environmental products.

The paper describes an outcome of experimental work on TMMF-based biosensor coated with HLD for label-free haloalkane detection. Mini protein can be used as an effective bioreceptor with some structural modification to improve functionality and stability.

The main aim of this study is to investigate the whey protein profiles of different commercially available fermented milk drinks that might have been influenced by the growth of probiotics bacteria that have been added according to the claims made by the manufacturer.

The growth and the subsequent effect of probiotics on whey proteins were investigated through the peptide profiles of the hydrolysed whey protein. The profiles of whey proteins in skimmed milk and the four other probiotic fermented milk drinks were obtained by using the FPLC technique. Changes in whey proteins profiles in fermented milks were evaluated by comparing them with those of unfermented skimmed milk (control). The four samples were those of Yakult, Actimel, Muller and Tesco probiotic cranberry drinks.

This work has shown that all samples demonstrated a degree of protein hydrolysis. The high level of hydrolysis in “Yakult” and “Actimel” drink samples might have been due to the nature of the process, the length of time of fermentation or the high level of proteolytic activities of the micro‐organisms used. When compared with casein, it seems that whey proteins are more resistant to hydrolysis. The results also indicated that only traces of α‐lactalbumin were left in the whey sample from “Yakult” drink. There were noticeable reductions in the other three samples. Orotic acid, on the other hand, showed a decrease in their concentration in all whey protein samples when compared with the skimmed milk sample, except for the “Actimel” sample, which showed a noticeable increase.

This work has shown that there were distinct differences between the control sample (skimmed milk) and the four commercially available probiotic milk‐based fermented health drinks when a direct comparison was carried out between these samples.

A shift to a healthy and sustainable diet (as recommended by the EAT Lancet Commission) needs to have a strong societal legitimation. This makes it relevant to investigate to what extent countries are using their Food-Based Dietary Guidelines (FBDGs) in ways that can stimulate such a shift.

Given the pivotal role of protein, the authors examined what patterns of protein-related recommendations are used to guide consumers and how these patterns are related to specific contexts and societal priorities of the countries.

The analysis of data from 93 countries worldwide revealed two emerging patterns of recommendations. One pattern (found in a cluster of 23% of the countries) combined positive advice about key protein sources with limiting messages to reduce (or replace) the consumption of animal protein. The other pattern (found in a cluster of 24%) encouraged both animal and plant protein, thereby diversifying the set of protein sources, without negative advice on animal-based food sources. The two patterns of recommendations were differently associated with health and nutrition variables, including the countries' level of animal protein supply (in particular, dairy) and the prevalence of overweight individuals among adult men.

For all stakeholders, it is of crucial importance to realize that an increasing number of countries in the world are moving in the direction of acknowledging and addressing the diet-health-environment nexus by adapting their patterns of recommendations for key protein sources.

This study is the first that reveals patterns in recommendations with respect to protein sources by different nations worldwide.

The prominence of wheat as the world's largest crop (in 1981 world production was almost 1.7 thousand million tonnes, of which about 40% went directly to human food use) owes much to its almost unique ability to be baked into bread. This ability is largely attributable to the physico‐chemical properties of wheat proteins, which enable a leavened dough to rise by trapping the carbon dioxide, produced during yeast fermentation, as discrete, small gas cells — a structure that is ‘set’ during baking. Another important type of food made from wheat is pasta and the suitability of wheat for this end use is also governed by the properties of wheat proteins. The suitability of wheats for other uses, such as cracker, biscuit and cake manufacture and domestic flour is also affected by these proteins.