Monique H. Vingerhoeds

Identification of salivary proteins at oil–water interfaces stabilized by lysozyme and β-lactoglobulin

In this research, we investigated the interaction occurring between oil-in-water emulsion droplets, stabilized by different emulsifiers, i.e. lysozyme and beta-lactoglobulin (beta-lg), and salivary proteins (SPs) with a molecular mass (M(r)) above about 10kDa. Different techniques, i.e. infrared spectroscopy, Western blotting, PAS staining and SDS-PAGE coupled to MS, were employed for this purpose. This study demonstrated the interaction between several salivary proteins and the emulsifiers at the oil-water interfaces. In particular, results show that the high M(r) mucin MUC5B was strongly bound to lysozyme stabilized emulsions, whereas beta-lg stabilized emulsions associated with MUC7 and, moderately, with MUC5B. Furthermore, we observed that salivary proteins in the range M(r) 10-100kDa associated differently with emulsion droplets. A large majority of SPs was found to interact with lysozyme stabilized emulsion droplets whilst in case of beta-lg stabilized emulsions, the SPs distribute more evenly between the fraction associated and non-associated with the droplets. A clear example is alpha-amylase (M(r) approximately 55kDa) which predominantly associates with lysozyme stabilized emulsion droplets, but not with beta-lg emulsion droplets. To conclude, our findings indicate that adsorption/association of salivary protein components onto the emulsion droplets is related to the type of emulsifying proteins at the oil-water interfaces and it is probably driven by the overall net charge at the droplets oil-water interfaces, i.e. positive for lysozyme stabilized emulsions and negative for beta-lactoglobulin stabilized emulsion at neutral pH.

Nudging children towards whole wheat bread: a field experiment on the influence of fun bread roll shape on breakfast consumption

BackgroundMany children do not eat enough whole grains, which may have negative health consequences. Intervention research is increasingly focusing on nudging as a way to influence food choices by affecting unconscious behavioural processes. The aim of this field study was to examine whether the shape of bread rolls is able to shift children’s bread choices from white to whole wheat during breakfast to increase whole grain intake.MethodsIn a between-subjects experiment conducted at twelve primary schools in the Netherlands, with school as the unit of condition assignment, children were exposed to an assortment of white and whole wheat bread rolls, both varying in shape (regular versus fun). Children were free to choose the type and number of bread rolls and toppings to eat during breakfast. Consumption of bread rolls was measured at class level via the number of bread rolls before and after breakfast. In addition, children (N = 1113) responded to a survey including questions about the breakfast.ResultsResults of the field experiment showed that about 76% of bread consumption consisted of white bread rolls. Consumption of white bread rolls did not differ according to shape (all P-values > 0.18). However, presenting fun-shaped whole wheat bread rolls almost doubled consumption of whole wheat bread (P = 0.001), particularly when the simultaneously presented white bread rolls had a regular shape (interaction P = 0.02). Survey results suggest that slight increases in perceived pleasure and taste are associated with these effects.ConclusionsOverall, presenting whole wheat bread in fun shapes may be helpful in increasing consumption of whole wheat bread in children. Future research could examine how improving the visual appeal of healthy foods may lead to sustained behaviour changes.

An In-Store Experiment on the Effect of Accessibility on Sales of Wholegrain and White Bread in Supermarkets

Even though whole grain foods have various health benefits, consumers have been found not to eat enough of them. Nudging interventions are built on the premise that food purchases and consumption are strongly influenced by the environment in which decisions are made. Little research has been conducted to examine the influence of a small and inexpensive nudging intervention on bread choices in a real-life supermarket context. An in-store experiment was conducted in two six-week periods in two supermarkets to investigate the effects of accessibility on consumers’ purchase of healthier whole grain and other types of bread. In the high accessibility condition, healthier bread was placed in a more convenient location for the shopper on the left side of the shelves where it was encountered first. In the low accessibility condition, it was placed on the right side. There were consistent significant differences in sales between supermarkets, types of bread, day of the week, but not between low and high accessibility. Additional research is needed to better understand the effects of convenience and accessibility on bread choices.

Oral processing and perception of food emulsions : the relevance for fat reduction in food

Abstract: The textural sensory functionality of emulsion droplets in foods is largely due to their effect on the rheological behaviour (such as viscosity and fracture behaviour), and importantly also to their effects on friction between the oral surfaces and on lubrication of the food bolus. Crucial in this is that much of this functionality is dependent on structural changes in the food emulsions that occur upon processing in the mouth. This chapter gives an overview of the main topics relevant for understanding the role of fat in the textural sensory perception of food emulsions, and discusses strategies to compensate for the sensory loss that accompanies fat reduction.

Saliva-induced emulsion flocculation: role of droplet charge

Human saliva is a complex heterogeneous biological fluid composed of proteins, electrolytes, small organic compounds and water.1–3 It is involved in several functions in the oral cavity and is responsible for maintaining oral health and for protection of the teeth and mucosal surfaces.4 Mixing with ...

Een verzorgde lunch op de basisschool: wat kost dat en wat mag dat volgens ouders kosten?

Kinderen in de basisschoolleeftijd eten te weinig groente, fruit en volkorenproducten. Melk en yoghurt worden steeds vaker vervangen door alternatieven met veel suiker [1]. Dit zien we ook terug in de lunchtrommels op basisscholen: er zijn grote verschillen in de samenstelling en kwaliteit van broodtrommels tussen kinderen op school en tussen scholen onderling [2, 3, 4]. De invoering van het continurooster op steeds meer basisscholen maakt de introductie van een verzorgde schoollunch mogelijk. Er zijn echter nog veel vragen over een verzorgde schoollunch in Nederland. Een daarvan is: wat is de voorkeur van ouders? En daaraan gekoppeld de vragen: wat kost dat en wat zijn ouders bereid ervoor te betalen? Dit artikel geeft een beeld van de voorkeuren van ouders met betrekking tot een verzorgde schoollunch en de kosten ervan, en van de betalingsbereidheid van ouders.

Effects of bread roll unit size on bread and energy intake in children

Background Bread choice • The average number of consumed bread rolls was 4.2 (SD=1.9). • White bread rolls were favourite: the first chosen bread roll was usually white (89%) regardless of size of offered rolls. 81% of total bread consumption was white. • Children ate more bread in grams when white rolls were larger-sized (Ps<0.001). Objective Although people tend to eat more when food is served in larger units (unit size effect), children often prefer food served in smaller units as they look more appealing. Whether unit size of bread rolls can be used to encourage children’s intake of whole wheat bread is unclear. Objective: To determine the effect of unit size of bread rolls on lunch energy and bread intake during a school lunch.