Massey Documents by Type
Permanent URI for this communityhttps://mro.massey.ac.nz/handle/10179/294
Browse
5 results
Search Results
Item The effect of emotional music on Just-About-Right and speeded-responses to chocolate(Elsevier Ltd, 2026-02-01) Wagner J; Poggesi S; Maggs R; Hort JResearch has demonstrated effects of emotional music on sensory perception of food, with many findings supporting a more favourable evaluation of foods when eaten while listening to positive music over negative emotional music. As the food industry becomes more focused on testing in realistic environments, there is a greater need to investigate the effects of auditory input on consumer perception when captured with measurement tools used in consumer sensory research. Consumers attending an event in New Zealand, took part in a chocolate tasting where they consumed milk or dark chocolate in positive and negative emotional music conditions. Consumer responses included emotional and sensory associations to the samples using a speeded response task, liking and Just-About-Right evaluations. Findings showed liking of dark chocolate was significantly higher in the positive as compared with the negative emotional music condition, whereas sensory changes were restricted to milk chocolate for the sweetness attribute where it was rated as higher in the positive as compared with the negative emotional music condition. Speeded emotional and sensory associations were highly susceptible to the effects of emotional music. Furthermore, exploratory penalty analysis revealed that emotional music can impact consumer feedback on attribute importance. This study builds on current understandings of the effects emotional music can have on automatic consumer responses, specifically speeded self-reported responses and gives further clarity on how the relationship between attributes and their link with liking may change with emotional music. The findings of this study offer a new insight into how emotional music can influence consumer and sensory science study outcomes when speeded self-report and JAR are used.Item Sensory and affective response to chocolate differing in cocoa content: A TDS and facial electromyography approach.(Elsevier B.V., 2023-08-08) Wagner J; Wilkin JD; Szymkowiak A; Grigor JExisting research has offered insight into facial activities and their associations with hedonic liking during the consumption of basic food samples and suggests facial changes during consumption are linked to the hedonic evaluation of tastes and, thus related to the taster's perception rather than the tastes themselves. This study tests whether, during the consumption of commercially available dark chocolate, a complex food product, which can be high in bitterness but expectedly so, how facial activities are linked to the bitterness levels and the hedonic liking of the samples. To do this we carried out two studies with untrained consumers, the first of which captured temporally dynamic sensory perception during the consumption of dark chocolate samples of 36% and 85% cocoa content, using the Temporal Dominance of Sensations (TDS) approach. The second study captured facial EMG over the corrugator and zygomaticus muscles during the consumption of dark chocolate samples (36%, 70%, and 85% cocoa). Specifically, the aim of this research was to investigate whether corrugator activity had a greater association with bitterness perception, linked to cocoa, or hedonic evaluation. Capturing the dynamic sensory profile of chocolate samples allowed an investigation into the time points most evident of sensory variation related to the bitterness and sweetness of the taste, allowing insight into whether facial activities also deviated during this time. These data offer evidence to suggest that corrugator was associated with hedonic evaluation during consumption of the samples, with the most liked samples (being those with 70% and 36% cocoa) eliciting similar corrugator activities and less activity than the least liked 85% cocoa content sample; however, there was also evidence to suggest a significant variation in participants' corrugator activity during the period of oral processing when bitterness was most evident in the 85% cocoa sample and sweetness was most evident in the 36% cocoa sample (i.e., the time when bitterness and sweetness were most divergent) Further investigation showed a variation in facial activities elicited during consumption of the 36% cocoa sample based on whether individuals were part of the group who favoured the 85% cocoa sample or the group favouring the 36% cocoa sample. The findings, therefore, suggest facial EMG, specifically over the corrugator, appears to be related to the hedonic evaluation of a complex food product and not the taste itself. Furthermore, being aware of the time points where sensory variations are most apparent between samples can allow for targeted investigation into facial EMG and its ability to distinguish food samples.Item Motivations for Caffeine Consumption in New Zealand Tertiary Students(MDPI (Basel, Switzerland), 2021-11-25) Stachyshyn S; Wham C; Ali A; Knightbridge-Eager T; Rutherfurd-Markwick KCaffeine-related health incidents in New Zealand have escalated over the last two decades. In order to reduce the risk of substance-related harm, it is important to understand the consumers' motivations for its use. This is especially true for tertiary students who are presumed to be at a higher risk due to seeking out caffeine's well-known cognitive benefits as well as the targeted marketing of such products to young adults. This study examined the habits and motivations for caffeine consumption in tertiary students in New Zealand. A previously validated caffeine consumption-habits (CaffCo) questionnaire was administered online to 317 tertiary students (n = 169 females), aged ≥16 years. Of the 99.1% of participants who regularly consumed caffeine, coffee (76.3%) tea (71.6%) and chocolate (81.7%) consumption were the most prevalent. Motivations for caffeinated-product consumption differed according to caffeine source. Tea was consumed for the warmth and taste, coffee was consumed to stay awake and for warmth, and chocolate, for the taste and as a treat. Marketing was not identified by participants as influencing their consumption of caffeinated products. Knowledge of motivations for caffeine consumption may assist in identifying strategies to reduce caffeine intake in those New Zealand tertiary students who regularly consume amounts of caffeine that exceed safe level.Item Caffeine Consumption Habits of New Zealand Tertiary Students(MDPI (Basel, Switzerland), 2021-04-28) Stachyshyn S; Ali A; Wham C; Knightbridge-Eager T; Rutherfurd-Markwick KAdverse effects associated with excessive caffeine consumption combined with increasing numbers and availability of caffeine-containing products are causes for concern. Tertiary students may be at increased risk of consuming excessive amounts of caffeine due to seeking caffeinated products with well-known wakefulness effects and cognitive benefits. This study explored caffeine consumption habits of New Zealand tertiary students (317; ≥16-years) using a previously validated caffeine consumption habits (CaffCo) questionnaire. Most (99.1%) regularly consumed caffeinated products, especially chocolate, coffee and tea, with coffee, tea and energy drinks contributing most to total caffeine intake. Median estimated caffeine intake was 146.73 mg·day-1, or 2.25 mg·kgbw-1·day-1. Maximum and minimum intakes were 1988.14 mg·day-1 (23.51 mg·kgbw-1·day-1) and 0.07 mg·day-1 (0.02 mg·kgbw-1·day-1), respectively. One-third (34.4%) of caffeine consumers ingested caffeine above the adverse effect level (3 mg·kgbw-1·day-1) and 14.3% above the safe limit (400 mg·day-1). Most caffeine consumers (84.7%), reported experiencing at least one 'adverse symptom' post-caffeine consumption, of which 25.7% reported effects leading to distress or negatively impacting their life. Experiencing 'adverse symptoms' did not, however, curtail consumption in the majority of symptomatic participants (~77%). Public health initiatives directed at tertiary students may be important to reduce potential caffeine-related harm.Item Oral processing of dark and milk chocolate : a thesis presented in fulfilment of the requirements for the degree of Master of Technology in Food Technology, the Riddet Institute, Massey University, Palmerston North, New Zealand(Massey University, 2012) Gaikwad, VishThe thesis reports novel scientific understanding and findings generated on the subject of chocolate oral processing. Research was carried out with a view to unravel the role of food (chocolate) - and human-related factors in governing structural and physical transformation of chocolate matrices during human oral processing. Dark and milk chocolate were studied as contrasting model matrices to investigate the influence of composition and physical properties of chocolates on microstructure and physical properties of ready-to-swallow chocolate boluses formed as a consequence of distinct eating and saliva incorporation strategies. Microstructure, and physical/material properties, in particular, particle size distribution, hardness, mechanical and rheological properties of melts, and thermal behaviour and solid fat content (SFC) of the chocolate models were characterised and compared. Differences in particle size distribution between the chocolates, and presence of milk ingredients (milkfat, milk powder, lactose) and surface-active agents (soy lecithin) in the milk chocolate, as opposed to their absence in the dark chocolate, were recognised and discussed as prominent factors contributing to underlying differences in microstructure and physical properties between the chocolate models. The dark chocolate was significantly harder as compared to milk chocolate, and in addition demonstrated greater firmness, consistency, cohesiveness, index of viscosity, yield stress and plastic viscosity of melt. Analysis of melting behaviour suggested that in comparison to milk chocolate, the dark chocolate had a slower melting-rate and greater SFC, and hence demonstrated greater energy requirement for complete liquefaction. This was reflected through the thermal parameters of solid fat index, melting onset, end and peak maximum, and enthalpy of melting assessed using differential scanning calorimetry. A 24 subject human panel study undertaken to investigate eating (mastication and swallowing) strategies of consumers suggested that chocolate eating behaviour varied considerably across consumers. Findings highlighted that chocolate eaters adapted their overall eating strategies in response to differences in physical and related-textural properties of chocolates. In particular, total number of chews and oral processing time for the complete masticatory sequence and until the first perception to swallow, significantly differed between the two chocolates. These eating parameters were greater in the case of dark chocolate as compared to milk chocolate. Furthermore, subjects also conserved their general eating patterns and maintained similar masticatory frequencies between chocolates. Taken together, it was postulated that chocolate composition and physical properties, as well as human-related physiological and behavioural factors influenced dynamics of chocolate oral transformation, and were consequently involved in modulation of mastication and swallowing strategies. Hierarchical cluster analysis and analysis of variance were successfully implemented for segregation of population into three clusters with significant differences in eating parameters. This was followed by principal component analysis which facilitated the selection of 3 test subjects who exercised distinct overall chocolate eating strategies significantly different from each other, and moreover were from a related parent cluster. Regardless of eating strategy, occurrence of several voluntary swallowing events before complete oral clearance of chocolates indicated that only a part of the bolus was ready-to-swallow at the first perception to swallow. Observation of expectorates confirmed that at this point, chocolate boluses constituted a pool of liquid bolus phase (molten chocolate + saliva) as well as cohesive bolus lumps (solid/partially-melted chocolate particles aggregated together by the action of saliva and molten fat). While the liquid phase was swallowed by subjects, cohesive lumps underwent further oral processing to be transformed into a swallowable consistency. Microstructure analysis of bolus liquid phase by optical microscopy and confocal laser scanning microscopy revealed a coarse oil-in-water emulsion microstructure in the case of either chocolate wherein, a relatively denser bolus structure resulting from extensive ingredient and fat globule flocculation was witnessed for dark chocolate boluses. Results further suggested that solid fat content-related physical properties and melting behaviour were related to saliva incorporation. Greater hardness and energy requirements for liquefaction, and slower rate of melting in dark chocolate resulted in relatively longer oral processing time invested by subjects in bolus preparation. This in turn resulted in higher moisture content in ready-to-swallow boluses of dark chocolate (40.25 wt%) as compared to milk chocolate (32.20 wt%). Furthermore, these properties also resulted in cohesive-lumps of dark chocolate boluses being significantly firmer and requiring greater work for compression. In contrast, adhesiveness of milk chocolate boluses was greater in comparison with dark chocolate boluses, and was explained through the presence of milk ingredients in its chocolate matrix. Subjects processed both chocolates to similar cohesiveness of bolus lumps, interestingly indicating that this property may not be chocolate-dependent. Nevertheless, bolus saliva contents at the first point of swallow, and all mechanical properties accept adhesiveness of bolus lumps, were subject-dependent. Results indicated that this effect could be largely related to variation in physiological parameters, in particular oral processing time and salivary flow rates. Interestingly, liquid phase viscosities of milk chocolate boluses were similar to that of dark chocolate within-subjects, while this property was also subject-dependent. Adaptation of eating strategies and saliva incorporation demonstrated by subjects in response to differences in chocolate texture, and the presence of a relatively greater percentage of water-soluble solids in milk chocolate were factors which supported the fact that ready-to-swallow boluses of both chocolates had similar viscosities. Subject-dependency of chocolate bolus viscosity was explained through physiological parameters of eating behaviour and saliva flow rate which influence final moisture content in the bolus liquid phase. Considering the importance of the continuous fat-phase in influencing oral processing and bolus formation of chocolates, effect of storage temperature (0°C, 20°C, 30°C)-induced physical changes in dark and milk chocolate on physical properties of ready-to-swallow boluses, and eating and saliva incorporation strategies of selected subjects was investigated. Thermal analysis revealed mainly SFC-related changes in the physical properties of hardness and enthalpy of melting (ΔHmelt). Relative to 20°C, storage at 0°C resulted in increased hardness and ΔHmelt for both chocolates, while an inverse effect resulted from storage at 30°C. In the case of both chocolates, all subjects adapted their oral processing time, number of chews and saliva incorporation strategies in positive relation to increase/decrease in hardness and ΔHmelt. Again, they conserved their general eating patterns, and maintained similar masticatory frequencies to form boluses suitable for swallowing. In the case of both chocolates, significant softening and relatively greater reduction in ΔHmelt of chocolate stored at 30°C resulted in significantly low firmness and work of spreading of bolus lumps obtained at the point of swallow. Once again, in the case of all subjects, adhesiveness of bolus lumps was independent of these changes in physical properties for either chocolate-type. Lastly, results suggested storage treatments resulted in each subject processing a similar chocolate-type to different endpoints in terms of bolus liquid phase viscosity. Different SFC which governed the relative extent of melting that a chocolate underwent until the point of swallow, may have influenced the degree of bolus dilution, and hence its viscosity. Throughout this study, the excellent within-subject repeatability in eating strategies, saliva incorporation, and rheological properties of ready-to-swallow bolus for a particular chocolate- and/or texture-type was noteworthy.