Heightened sour preferences during childhood

Basic research has revealed that the chemical sensory world of children is different from that of adults, as evidenced by their heightened preferences for sweet and salty tastes. However, little is known about the ontogeny of sour taste preferences, despite the growing market of extreme sour candies. The present study investigated whether the level of sourness most preferred in a food matrix and the ability to discriminate differences in sour intensity differed between 5- to 9-year-old children and their mothers, by using a rank-by-elimination procedure embedded in the context of a game. Mothers also completed a variety of questionnaires and children were asked several questions to assess whether children's temperament and food preferences and habits related to sour preferences. The results indicated that, although every mother and all but two of the children (92%) were able to rank the gelatins from most to least sour, more than one-third (35%) of the children, but virtually none of the adults, preferred the high levels of sour taste (0.25 M citric acid) in gelatin. Those children who preferred the extreme sour tastes were significantly less food neophobic (P < 0.05) and tended to experience a greater variety of fruits when compared with the remaining children (P = 0.11). Moreover, the children's preference for sour tastes generalized to other foods, such as candies and lemons, as reported by both children and mothers. These findings are the first experimental evidence to demonstrate that sour taste preferences are heightened during childhood and that such preferences are related to children's food habits and preferences. Further research is needed to unfold the relationship between the level of sour taste preferred and the actual consumption of sour-tasting foods and flavors in children.

Sour taste preferences of children relates to preference for novel and intense stimuli

Previous research has suggested that some children have a preference for sour tastes. The origin of this preference remains unclear. We investigated whether preference for sour tastes is related to a difference in rated sour intensity due to physiological properties of saliva, or to an overall preference for intense and new stimuli. Eighty-nine children 7–12 years old carried out a rank-order procedure for preference and category scale for perceived intensity for four gelatins (i.e. 0.0 M, 0.02 M, 0.08 M, 0.25 M added citric acid) and four yellow cards that differed in brightness. In addition, we measured their willingness to try a novel candy and their flow and buffering capacity of their saliva. Fifty-eight percent of the children tested preferred one of the two most sour gelatins. These children had a higher preference for the brightest color (P < 0.05) and were more likely to try the candy with the unknown flavor (P < 0.001) than children who did not prefer the most sour gelatins. Preference for sour taste was not related with differences in rated sour intensity, however those who preferred sour taste had a higher salivary flow (P < 0.05). These findings show that a substantial proportion of young children have a preference for extreme sour taste. This appears to be related to the willingness to try unknown foods and preference for intense visual stimuli. Further research is needed to investigate how these findings can be implemented in the promotion of sour-tasting food such as fruit.

Sweet and sour preferences during childhood : role of early experiences

We investigated the effects of early experience on sweet and sour preferences in children. Eighty-three children were divided into four groups based on the type of formula fed during infancy and age. By using a forced-choice, sip-and-swallow procedure, we determined the level of sweetness and sourness preferred in juice. Children who were fed protein hydrolysate formulas, which have a distinctive sour and bitter taste and unpleasant odor, preferred higher levels of citric acid in juice when compared to older children who were fed similar formulas. No such difference was observed between the groups for sweet preference. However, the level of sweetness preferred in juice was related to the sugar content of the child's favorite cereal and whether the mother routinely added sugar to their foods. These data illustrate the wide variety of experiential factors that can influence flavor preferences during childhood.

The isolation and characterisation of humic acids using a variety of alkaline extractants

The investigation into humic acid; chemistry examined the effect the extraction technique used to isolate humic material from the sediment had on the chemical/structural composition and yield of the acid; compared the various isolation techniques used in the literature and developed an extraction technique which minimises the solubilisation of the heavy metals from the inorganic sediment and, examined the complexation capacity of humic acids derived from a sediment source in relation to the heavy metal content and extraction technique.

Algorithms and applications of preference based ranking for information retrieval

In this thesis, the author designed three sets of preference based ranking algorithms for information retrieval and provided the corresponsive applications for the algorithms. The main goal is to retrieve recommended, high similar and valuable ranking results to users.

The place of place : case studies of place in Victorian planning schemes

Built environment and lived experience are inextricably interwoven. The Australian State of Victoria’s planning framework prioritises the physical characteristics of space above their socio-psychological correlates, as reflected in the relatively limited remit of ‘place’ in formal decision-making. The Victorian planning model struggles to accommodate the uniqueness of specific places in the process of development, despite the driving role it plays in expansion. A literature review investigating definitions of place and place identity determined that although place has been defined variously, and at times with some contradiction, there is broad consensus that it can be understood as the interrelation between the physical characteristics of a landscape and the sensory faculties of an individual and an individual’s experience. This interrelationship is in turn determined by social constructs. Depending on an individual’s length of residence in a particular physical location, place influences individual and social psychology through both the formation of place attachment and identity. While place attachment to landscapes has been described using a variety of complex methodologies, translation of this work into architectural and planning practice has been limited within Australia in general and Victoria in particular. The Victorian Shires of Surf Coast and Frankston are considered as examples of current best practice in integrating place into planning. Key issues highlighted in the conclusion include: the difficulties of incorporating qualitative information within the Victorian Planning Scheme; the importance of correctly measuring place attachment, rather than landscape preference; and the complexities, costs and ethical implications of describing place attachment for integration within the planning system.

The effect of rice variety and parboiling on in vivo glycemic response

Improved and traditional rice varieties grown in Sri Lanka namely, Bg 300, Bg 352, Bg 358, Bg 406, LD 356, Rathkaral, Wedaheenati and Heendikwel were studied for their in vivo glycemic response. Proximate compositions and amylose content of rice were determined according to standard methods and available carbohydrate content was calculated using the difference method. The in vivo glycemic response of selected improved and traditional rice varieties was assessed by determining the glycemic index (GI) using ten healthy subjects. Further, the effect of parboiling of rice on glycemic response was also assessed. The crude protein content was higher in parboiled rice as compared to nonparboiled rice. According to the amylose content, rice varieties studied were classified as intermediate and high amylose rice. The amylose content of Bg 406 was the lowest (20.18% ±0.17) while Rathkaral showed the highest (29%±0.07). The Glycemic index of rice varieties studied ranged from 57±1 to 73± 2. The Wedaheenati variety exhibited the lowest GI while Bg 406 exhibited the highest GI value. Unparboiled Bg 406, LD 356 and parboiled Bg 406 were classified as high GI foods while the rest of the rice varieties studied were categorized as intermediate GI foods. Parboiled rice brought about a reduction in glycemic response in healthy subjects. The maximum reduction of 10% in glycemic index upon parboiling was observed with Bg 352. The traditional rice produced significantly lower (p<0.05) postprandial glycemic effect than did the improved rice. By their low post-prandial glycemic response they could be potentially useful in low GI diets.

Using brand knowledge to predict beer brand preference and loyalty for samples of new frequent users in Perth and Beijing

This study tests a model of Brand Knowledge and Brand Equity of brands of beer on new and frequent users in two populations that differ in their stage of the beer product life cycle and culture. Using Multiple Logistic Regression (MLR) and Binomial Logistic Regression (BLR), models based on the respondents' Brand Knowledge are able to correctly identify Chinese respondents’ preferred brand of beer 56% of the time, while correctly identifying 77% of respondents in an Australian sample when three top brands are tested. The model could further identify 67% of those that stay or switch in both the Australian and the Chinese samples.

Play preference of children with ADHD and typically developing children in Brazil : a pilot study

Background/aim: Children with attention deficit hyperactivity disorder (ADHD) have been reported to have play deficits, which can cause problems in occupational development. The aim of this paper was to report research findings on children with ADHD and typically developing children in relation to preference of play partners, play places, toys and type of play.

Methods: Thirty-two school aged children from lowsocioeconomic status were divided into two groups. One group of 16 children with ADHD were matched with 16 typically developing children.

Results and conclusion: There were no significant differences between the two groups in relation to play partners, with classmates being the most frequent play partner for both groups. There were significant differences between the two groups in preferred place to play. Children with ADHD preferred to play in school and typically developing children preferred to play on the street. There were significant differences in relation to toys and type of play engaged in with children with ADHD preferring educational materials and typically developing children preferring electronic games. These findings add to knowledge of Brazilian children with ADHD and their play preferences. Comparisons are made with research with Australian children with and without ADHD.

Preference networks : probabilistic models for recommendation systems

Recommender systems are important to help users select relevant and personalised information over massive amounts of data available. We propose an unified framework called Preference Network (PN) that jointly models various types of domain knowledge for the task of recommendation. The PN is a probabilistic model that systematically combines both content-based filtering and collaborative filtering into a single conditional Markov random field. Once estimated, it serves as a probabilistic database that supports various useful queries such as rating prediction and top-N recommendation. To handle the challenging problem of learning large networks of users and items, we employ a simple but effective pseudo-likelihood with regularisation. Experiments on the movie rating data demonstrate the merits of the PN.