Utilisation of Kluyveromyces marxianus for the ethanolic fermentation of lactose in skim milk permeate
- Authors: Wakeling, Lara
- Date: 1994
- Type: Text , Thesis , Masters
- Full Text:
- Description: "In this study ethanoal was produced via fermentation of skim milk permeate using Kluyveromyces marxianus".
- Description: Master of Applied Science
Composition of pecan cultivars Wichita and Western Schley [Carya illinoinensis (Wangenh.) K. Koch] grown in Australia
- Authors: Wakeling, Lara , Mason, Richard , D'Arcy, Bruce , Caffin, Nola
- Date: 2001
- Type: Text , Journal article
- Relation: Journal of Agricultural and Food Chemistry Vol. 49, no. 3 (2001), p. 1277-1281
- Full Text: false
- Reviewed:
- Description: Pecans from the cultivars Wichita and Western Schley [Carya illinoinensis (Wangenh.) K. Koch] collected over three years were analyzed for the following constituents: total lipid content; fatty acid profiles; sucrose content; protein; total dietary fiber; the minerals magnesium, calcium, potassium, sulfur, phosphorus, boron, copper, iron, manganese, sodium, zinc, and aluminum; vitamin C; and lipase and lipoxygenase activities. Year of harvest and cultivar had little effect on the composition of the pecans. Overall, protein content was the only constituent that differed between pecans grown in Australia and those grown in the United States. This difference is probably related to differences in growing location and horticultural practices between the two countries.
Maturation studies of pecan nuts grown in Queensland
- Authors: Wansri, R. , Mason, Richard , Wakeling, Lara , Nottingham, S. M.
- Date: 2001
- Type: Text , Journal article
- Relation: Food Australia Vol. 53, no. 12 (2001), p. 562-567
- Full Text: false
- Reviewed:
- Description: Changes in chemical composition, physical and sensory characteristics were followed in two pecan cultivars Wichita and Western Schley harvested from a commercial orchard at Gatton in Queensland seven times during 1996. Testa colour of both pecan cultivars darkened and opalescence decreased as the nuts matured. Bitterness of Western Schley pecans decreased with maturity. Colour of shuck, shell and kernel of both cultivars developed as the nuts matured. Wichita pecans were larger than Western Schley at all harvest times. Both nut-in-shell and kernel moisture decreased with maturity, whereas oil and sucrose contents increased. Both pecan cultivars had reached advanced maturation by the first harvest on March 18.
Opalescence in Australian-grown pecan kernels : Occurrence and causes
- Authors: Wakeling, Lara , Mason, Richard , D'Arcy, Bruce , Caffin, Nola
- Date: 2002
- Type: Text , Journal article
- Relation: Journal of Food Science Vol. 67, no. 8 (2002), p. 2873-2880
- Full Text: false
- Reviewed:
- Description: Opalescence is an unattractive browning of the interior of the pecan kernel compared to the white interior of normal kernels. The discoloration is due to the presence of free oil, resulting from decompartmentalization in the endosperm of opalescent pecans. Using a subjective scoring system, approximately 70% of Australian-grown pecan kernels tested were found to exhibit opalescence to some degree. Evaluation of kernels for opalescence during the harvesting-processing chain showed that opalescence first becomes evident in kernels after mechanical cracking. Opalescent kernels were found to have lower levels of calcium and higher amounts of oil compared to nonopalescent kernels. Differential scanning calorimetry showed that kernels do not freeze at -18°C.
- Description: 2003000167
Microscopic structure of opalescent and nonopalescent pecans
- Authors: Wakeling, Lara , Mason, Richard , D'Arcy, Bruce , Caffin, Nola , Gowanlock, D.
- Date: 2003
- Type: Text , Journal article
- Relation: Journal of Food Science Vol. 68, no. 7 (2003), p. 2238-2242
- Full Text: false
- Reviewed:
- Description: The ultrastructure of pecans was investigated using light microscopy, environmental scanning electron microscopy, scanning electron microscopy, and transmission electron microscopy. Specific methodology for the sample preparation of pecans for electron microscopy investigations was developed. Electron microscopy of the ultrastructure of opalescent (discoloration of the interior) and nonopalescent kernels revealed that cellular damage was occurring in opalescent kernels. The damage was due to cell wall and membrane rupture, which accounted for the release of oil throughout the kernel. This rupture is due to the lower level of calcium in the cell membranes of opalescent pecans, as shown by energy dispersive X-ray spectrometry, making them more susceptible to damage.
- Description: C1
- Description: 2003000527
Nutritional aspects of food extrusion : A review
- Authors: Singh, Shivendra , Gamlath, Shirani , Wakeling, Lara
- Date: 2007
- Type: Text , Journal article
- Relation: International Journal of Food Science and Technology Vol. 42, no. 8 (2007), p. 916-929
- Full Text: false
- Reviewed:
- Description: Summary Extrusion cooking, as a multi-step, multi-functional and thermal/mechanical process, has permitted a large number of food applications. Effects of extrusion cooking on nutritional quality are ambiguous. Beneficial effects include destruction of antinutritional factors, gelatinisation of starch, increased soluble dietary fibre and reduction of lipid oxidation. On the other hand, Maillard reactions between protein and sugars reduce the nutritional value of the protein, depending on the raw material types, their composition and process conditions. Heat-labile vitamins may be lost to varying extents. Changes in proteins and amino acid profile, carbohydrates, dietary fibre, vitamins, mineral content and some non-nutrient healthful components of food may be either beneficial or deleterious. The present paper reviews the mechanisms underlying these changes, as well as the influence of process variables and feed characteristics. Mild extrusion conditions (high moisture content, low residence time, low temperature) improve the nutritional quality, while high extrusion temperatures (≥200 °C), low moisture contents (<15%) and/or improper formulation (e.g. presence of high-reactive sugars) can impair nutritional quality adversely. To obtain a nutritionally balanced extruded product, careful control of process parameters is essential. © 2007 Institute of Food Science and Technology Trust Fund.
- Description: C1
- Description: 2003004850
Retention of essential amino acids during extrusion of protein and reducing sugars
- Authors: Singh, Shivendra , Wakeling, Lara , Gamlath, Shirani
- Date: 2007
- Type: Text , Journal article
- Relation: Journal of Agricultural and Food Chemistry Vol. 55, no. 21 (2007), p. 8779-8786
- Full Text: false
- Reviewed:
- Description: This research investigates the retention of essential amino acid profiles of products during the extrusion of proteins and reducing sugars. Animal proteins (egg and milk protein at 10 and 30% levels) and reducing sugars (fructose and galactose at 0, 2, and 8% levels), with pregelatinized wheat flour, were extruded at 110 and 125°C product temperatures and feed moistures of 19 and 23.5% for egg protein and 13.75 and 16% for milk protein. The nutritional property analyzed was essential amino acid retention, and sugar retention was also considered to understand the relationship of sugars with retention of amino acids. Lysine showed the lowest retention (up to 40%) of all the essential amino acids. Retention of other essential amino acids varied from 80 to 100% in most situations. Apart from lysine, tryptophan, threonine, and methionine were found to be significantly changed (P < 0.05) with processing conditions. Increased protein and sugar levels resulted in a significant degradation of lysine. Greater lysine retention was found at a lower temperature and higher feed moisture. Results of sugar retention also showed similar patterns. The products made from fructose had greater lysine retention than products made from galactose with any type of protein. The outcomes of this research suggested that the combination of milk protein and fructose at a lower temperature and higher feed moisture is most favorable for developing high-protein extruded products. © 2007 American Chemical Society.
- Description: C1
- Description: 2003004841
Colour and texture of apples high pressure processed in pineapple juice
- Authors: Perera, Niranjalie , Gamage, Thambaramala , Wakeling, Lara , Gamlath, G. , Versteeg, Cornelis
- Date: 2010
- Type: Text , Journal article
- Relation: Innovative Food Science and Emerging Technologies Vol. 11, no. 1 (2010), p. 39-46
- Full Text: false
- Description: Cubes of Granny Smith and Pink Lady apples were vacuum packed in barrier bags with 0% to 50% (v/v) pineapple juice (PJ) at 20°Bx and subjected to high pressure processing (HPP) at 600 MPa for 1–5 min (22 °C). The in-pack total colour change (ΔE) was observed over 4 weeks at 4 °C. Within <1 week of storage at 4 °C, texture, polyphenoloxidase, pectinmethylesterase activities, changes in ΔE and visual browning after opening the bags during air exposure (22 °C; 21% O2 ) for 5 h were also monitored. During the 4 weeks storage in bag visible colour changes were not observed. Texture and ΔE after 5 h air exposure were significantly affected by the apple variety, HPP time and % PJ used. The combined treatment significantly reduced residual PPO activity while PME activity was not affected in both varieties. Pineapple juice in combination with HPP could be used as a natural preservation system for minimally processed apples. Industrial relevance: Browning upon opening the packs and during air exposure can adversely affect the quality of fresh-cut fruits. Combined treatment of high pressure processing (HPP) and use of pineapple juice has the potential to prevent browning for several hours giving sufficient time for presentation and use in domestic and foodservice environment where high quality fresh-like fruit is required.
- Description: Cubes of Granny Smith and Pink Lady apples were vacuum packed in barrier bags with 0% to 50% (v/v) pineapple juice (PJ) at at 20°Bx and subjected to high pressure processing (HPP) at 600 MPa for 1-5 min (22 °C). The in-pack total colour change (
The effect of water-soluble vitamins on spoilage organisms in beer
- Authors: Hucker, Barry , Wakeling, Lara , Vriesekoop, Frank
- Date: 2010
- Type: Text , Conference paper
- Relation: 31st Asia Pacific Convention 2010
- Full Text:
- Reviewed:
- Description: The vitamin content of beer and brewing related products might not only be of interest from a human health perspective, but determining their presence and relative quantities might also help to understand the role they play in product stability. Water-soluble vitamins are important in the brewing industry, as they are essential nutrients for yeasts and potential spoilage organisms. The presence of particular vitamins in beer has been linked to deterioration (light strike) and it is possible that many vitamins may be linked to increased bacterial spoilage potential in beer. There is strong evidence to support that lactic acid bacteria require a variety of vitamins in order to grow effectively and can aid in the increased spoilage of beer and beer related products. This study investigates the effect of a variety of water-soluble vitamins on the growth of commonly found spoilage organisms, Lactobacillus brevis and Pediococcus damnosus.
Non-thermal food processing: impact on chemical, nutritional and bioactive
- Authors: Gamlath, Shirani , Wakeling, Lara
- Date: 2011
- Type: Text , Book
- Full Text:
- Reviewed:
Non-thermal food processing: Impact on chemical, nutritional and bioactive components
- Authors: Gamlath, Shirani , Wakeling, Lara
- Date: 2011
- Type: Text , Book
- Full Text: false
- Reviewed:
- Description: This book focuses on current research in the application of non-thermal technologies such as high pressure processing (HPP), pulsed electric field (PEF) and ultrasonics (US) and their impact on nutritional and bioactive components in a range of food commodities, with an emphasis on identifying suitable processing regimes for commercial applications. Pressures around 400-600 MPa at shorter treatment times retain nutritional properties and enhance the retention of bioactive components in foods with high levels of antioxidant activity. PEF indicated superior results in extracting phenolic and anthocyanins in fruit juices compared to HPP and US due to the electroporation of cellular membranes. However, more research with standardised processing conditions, such as pulse geometry, pulse duration, treatment time and energy levels, on a range of commodiites are necessary to validate PEF conditions for commercial processes. Ultrasonic in combination with mild temperature, enzymes and other non-thermal technologies has a great potential for extraction of nutritional and bioactive components from plant materials with reduced energy, chemicals and processing waste. While HPP technologies are being used commercially, further research and standardisation of processing conditions are required before other non-thermal technologies see commercial application. © 2011 by Nova Science Publishers, Inc. All rights reserved.
The quantitative analysis of thiamin and riboflavin and their respective vitamers in fermented alcoholic beverages
- Authors: Hucker, Barry , Wakeling, Lara , Vriesekoop, Frank
- Date: 2011
- Type: Text , Journal article
- Relation: Journal of Agricultural and Food Chemistry Vol. 59, no. 23 (2011), p. 12278-12285
- Full Text: false
- Reviewed:
- Description: This research aimed to develop a simple and effective method for analyzing thiamin (B 1), riboflavin (B 2) and their respective vitamers by high performance liquid chromatography (HPLC) in fermented alcoholic beverages. The method developed here employs a phosphate buffer/methanol gradient elution on a single reverse phase column, coupled with independent fluorescent detection regimes. It also employs a precolumn derivatization to convert thiamin to thiochrome via an alkaline potassium ferricyanide solution. The method described here allowed a spike recovery of better than 97%, with a typical linear detection range (R 2 ≥ 0.9997) between ≥5 and ≥500
Trends in high pressure processing of foods: Food quality and bioactive components
- Authors: Gamlath, Shirani , Wakeling, Lara
- Date: 2011
- Type: Text , Book chapter
- Relation: New Topics in Food Engineering p. 109-138
- Full Text: false
- Reviewed:
- Description: High pressure processing (HPP) is a non-thermal food processing technology that offers great potential for the processing of a wide range of food products. Application of HPP can inactivate micro-organisms, affect food-related enzymes and modify structures with minimal changes to nutritional and sensory quality aspects of foods. The effects of high pressure on the inactivation of micro-organisms in food have been thoroughly reviewed. Recent research on HPP has mainly focused on fruits and vegetables with an emphasis on food quality and bioactive components. This chapter highlights the current trends in HPP research and provides a summary of the available findings on the effect of HPP on chemical, nutritional and bioactive components and health related properties of a wider range of commodities. Strategies to maintain the quality attributes and health related components in HPP foods and identification of the gaps for future research in HPP are also discussed. © 2011 by Nova Science Publishers, Inc. All rights reserved.
Investigations into the thiamine and riboflavin content of malt and the effects of malting and roasting on their final content
- Authors: Hucker, Barry , Wakeling, Lara , Vriesekoop, Frank
- Date: 2012
- Type: Text , Journal article
- Relation: Journal of Cereal Science Vol.56, no.2 (2012), p.300-306
- Full Text: false
- Reviewed:
- Description: A simple and effective method for the analysis of thiamine (B1) and riboflavin (B2) vitamers, in unmalted and malted grains, by high performance liquid chromatography (HPLC) has been developed. This method makes use of trichloroacetic acid (TCA) as an extraction medium to effectively clean up the sample and analyze the vitamer content with high accuracy (R2 > 0.9992; %RSD < 5%). This method was employed in the routine analysis of a wide range of malted and unmalted grains, and it was found that lighter colored malts contain higher concentrations (2–5 times higher) of thiamine and riboflavin vitamers compared to darker colored malts. The malting process has no effect on the overall riboflavin content; however, both steeping and kilning processes cause increases in thiamine vitamer content. Roasting profiles show that thiamine and riboflavin vitamer concentrations are significantly effected when the temperature reaches 120 °C, which explains why roasted products have lower vitamer content than paler malts.
- Description: A simple and effective method for the analysis of thiamine (B
Relevance of chemistry practicals - First years student's perspective at a Regional University in Victoria, Australia
- Authors: Wakeling, Lara , Naiker, Mani , Aldred, Peter
- Date: 2013
- Type: Text , Conference paper
- Relation: Australian Conference on Science and Mathematics Education (The 19th UniServe Science Conference) p. 169-173
- Full Text: false
- Reviewed:
Approaches to study in undergraduate nursing students in regional Victoria, Australia
- Authors: Brown, Stephen , Wakeling, Lara , Naiker, Mani , White, Sue
- Date: 2014
- Type: Text , Journal article
- Relation: International Journal of Nursing Education Scholarship Vol. 11, no. 1 (2014), p. 1-10
- Full Text: false
- Reviewed:
- Description: In developmental research to devise a strategy to identify students who may benefit from assistance with learning habits, approaches to study were explored in undergraduate nursing students (n=122) enrolled in a compulsory first-year course in physiology at a regional Australian university. The course constituted 30 credits (25%) of their first year of study. Using the Approaches and Study Skills Inventory (ASSIST), students were identified as adopting a deep (n=38, 31%), strategic (n= 30, 25%), or a surface (n=54, 44%) approach to study. Internal consistency (Cronbach's alpha [
Effect of spatial distribution of wax and PEG-isocyanate on the morphology and hydrophobicity of starch films
- Authors: Muscat, Delina , Adhikari, Raju , Tobin, Mark , McKnight, Stafford , Wakeling, Lara , Adhikari, Benu
- Date: 2014
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 111, no. (2014), p. 333-347
- Full Text:
- Reviewed:
- Description: This study proposes a novel method for improving surface hydrophobicity of glycerol plasticized high amylose (HAG) films. We used polyethylene glycol isocyanate (PEG-iso) crosslinker to link HAG and three natural waxes (beeswax, candelilla wax and carnauba wax) to produce HAG + wax + PEG-iso films. The spatial distributions of wax and PEG-iso across the thickness of these films were determined using Synchrotron-based Fourier transform infrared spectroscopy. The hydrophobicity and surface morphology of the films were determined using contact angle (CA) and scanning electron microscopic measurements, respectively. The distribution patterns of wax and the PEG-iso across the thickness of the film, and the nature of crystalline patterns formed on the surface of these films were found to be the key factors affecting surface hydrophobicity. The highest hydrophobicity (CA >90°) was created when the PEG-iso was primarily distributed in the interior of the films and a hierarchical circular pinnacle structure of solidified wax was formed on the surface. © 2014 Elsevier Ltd.
Vitamins in brewing: The impact of wort production on the thiamine and riboflavin vitamer content of boiled sweet wort
- Authors: Hucker, Barry , Wakeling, Lara , Vriesekoop, Frank
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of the Institute of Brewing Vol. 120, no. 3 (2014), p. 164-173
- Full Text: false
- Reviewed:
- Description: Wort production contains a number of processing steps that are aimed at the optimal extraction of nutrients from malt, including vitamins. This research revealed that the different wort production processing steps imposed different influences on the thiamine and riboflavin vitamer content of the final sweet wort. These vitamins play vital roles within yeast metabolism, where they act as enzyme cofactors. As such thiamine vitamers play a crucial role in many decarboxylating enzymes, while riboflavin vitamers play an integral role in energy production and redox maintenance. While mashing releases valuable starch into the liquor, both thiamine and riboflavin are also extracted. The extraction of these vitamins is the greatest at 65°C and is indirectly linked to the amylase activity. When the starches are broken down during mashing, the thiamine and riboflavin vitamers are gradually released into the mash liquor. The boiling and trub removal (whirlpool) processes impose losses in both vitamins owing to the high temperatures exhibited during these stages. While hop pellets were shown to contribute a small proportion of the vitamers studied, the use of kettle finings caused a significant reduction in both thiamine and riboflavin vitamers.
- Description: C1
Approaches and Study Skills Inventory for Students (ASSIST) in an introductory course in chemistry
- Authors: Brown, Stephen , White, Sue , Wakeling, Lara , Naiker, Mani
- Date: 2015
- Type: Text , Journal article
- Relation: Journal of University Teaching and Learning Practice Vol. 12, no. 3 (2015), p. 1-12
- Full Text: false
- Reviewed:
- Description: Approaches to study and learning may enhance or undermine educational outcomes, and thus it is important for educators to be knowledgeable about their students’ approaches to study and learning. TheApproaches and Study Skills Inventory for Students(ASSIST) – a 52 item inventory which identifies three learning styles (Deep, Strategic, and Surface), was given to first year undergraduate students undertaking an introductory chemistry course. Completed inventories (n=103, 85% response), included 30 BSc Biomedicine, 15 BSc Food and Nutrition, 22 BSc Geology, 18 BSc Science students, and a further 18 students on unnamed BSc pathways. The dominant learning style adopted was the Surface approach, with a mean score (SD) of 2.94 (0.54). The preference of the surface approach was consistent for all BSc pathways.There was a higher mean score for the strategic learning style in males (n= 59) compared to females (n=44) with no gender-based differences in either the deep or the surface learning styles.A surface approach may not necessarily indicate a lack of interest in chemistry, rather chemistry may be perceived as being peripheral to the students’ interests – this may be a problem when students with a diverse range of career aspirations study common content in large, first year introductory courses. Identifying students that adopt a surface learning style at an early stage in the undergraduate education journey is an important step in effectively targeting educational resources aimed at enhancing students’ learning habits.
Attitude to the study of chemistry and its relationship with achievement in an introductory undergraduate course
- Authors: Brown, Stephen , White, Sue , Sharma, Bibhya , Wakeling, Lara , Naiker, Mani , Chandra, Shaneel , Gopalan, Romila , Bilimoria, Veena
- Date: 2015
- Type: Text , Journal article
- Relation: Journal of the Scholarship of Teaching and Learning Vol. 15, no. 2 (2015), p. 33-41
- Full Text: false
- Reviewed:
- Description: A positive attitude to a subject may be congruent with higher achievement; however, limited evidence supports this for students in undergraduate chemistry – this may result from difficulties in quantifying attitude. Therefore, in this study, the Attitude to the Study of Chemistry Inventory (ASCI) – a validated instrument to quantify attitude, was used to measure attitude to chemistry in 125 undergraduates studying an introductory course in chemistry, as part of a BSc Chemistry major. The 13 week course contained 4 summative assessments: practical (PRAC), tutorial (TUT), on-line web-based learning (OWL), and a final exam (FE). Sub-scales within ASCI which quantify the ‘affective’ and ‘cognitive’ components of attitude were determined. Firstly, for all 125 students, weak correlations (r) between the affective scale score and FE (r=0.275, P<0.01) and TOTAL (r=0.228, P<0.05), were recorded. Secondly, a low achieving (LA, n=48) and a high achieving (HA, n=77) group were identified using a cluster analysis procedure. The HA group scored higher than the LA group in PRAC, OWL, FE and TOTAL (all P<0.001), but the clusters were not different in their scores for either the affective or the cognitive components of attitude. There was no correlation between attitude and achievement in the HA group, and only one weak positive correlation (0.409), between the affective score and achievement in the LA group. We suggest that although a positive attitude may be an important part of the undergraduate experience, it is at best only weakly associated with achievement in undergraduate chemistry.