by Lee Man Yi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 125-137). / Abstract also in Chinese. / THESIS COMMITTEE --- p.i / ACKNOWLEDGEMENTS --- p.ii / ABSTRACT --- p.iii / ABSTRACT (Chinese version) --- p.v / TABLE OF CONTENTS --- p.vi / LIST OF TABLES --- p.xi / LIST OF FIGURES --- p.xv / LIST OF ABBREVIATIONS --- p.xvii / Chapter CHAPTER ONE: --- INTRODUCTION --- p.1 / Chapter 1.1 --- Background of mushrooms --- p.1 / Chapter 1.1.1 --- Cultivated mushrooms --- p.1 / Chapter 1.1.1.1 --- Volvariella volvacea --- p.3 / Chapter 1.1.1.2 --- Pleurotus sajor-caju --- p.4 / Chapter 1.1.1.3 --- Pleurotus tuber-regium --- p.5 / Chapter 1.1.2 --- Chemical composition and nutritional value --- p.6 / Chapter 1.1.3 --- Composition and structure of fungal cell wall --- p.9 / Chapter 1.1.4 --- Medicinal attributes of β-glucan in mushrooms --- p.10 / Chapter 1.1.5 --- Structure and antitumor activity β-glucan --- p.11 / Chapter 1.2 --- Dietary fiber --- p.14 / Chapter 1.2.1 --- Composition of dietary fiber --- p.14 / Chapter 1.2.2 --- Preparation of dietary fiber --- p.18 / Chapter 1.3 --- Structural analysis of polysaccharides --- p.19 / Chapter 1.3.1 --- Isolation of polysaccharides --- p.19 / Chapter 1.3.2 --- Methylation analysis --- p.20 / Chapter CHAPTER TWO : --- MATERIALS AND METHODS --- p.22 / Chapter 2.1 --- Sources and preparation of mushroom samples --- p.22 / Chapter 2.1.1 --- V. volvacea --- p.22 / Chapter 2.1.2 --- P. sajor-caju --- p.22 / Chapter 2.1.2.1 --- Fungal strain --- p.22 / Chapter 2.1.2.2 --- Production of spawn --- p.22 / Chapter 2.1.2.3 --- Production of fruiting bodies --- p.23 / Chapter 2.1.3 --- p. tuber-regium --- p.23 / Chapter 2.2 --- Analysis of mushroom composition --- p.24 / Chapter 2.2.1 --- Moisture content --- p.24 / Chapter 2.2.2 --- Starch content --- p.24 / Chapter 2.2.2.1 --- Total glucose --- p.24 / Chapter 2.2.2.2 --- Free glucose --- p.25 / Chapter 2.2.2.3 --- Measurement of glucose content --- p.25 / Chapter 2.2.2.4 --- Total starch content --- p.25 / Chapter 2.2.3 --- Crude protein content --- p.26 / Chapter 2.2.4 --- Amino acid analysis --- p.27 / Chapter 2.3 --- Preparation of mushroom fiber material --- p.28 / Chapter 2.3.1 --- Enzymatic method --- p.28 / Chapter 2.3.1.1 --- Total dietary fiber (TDF) --- p.28 / Chapter 2.3.1.2 --- Insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) --- p.29 / Chapter 2.3.2 --- Chemical method --- p.29 / Chapter 2.3.2.1 --- Cell wall material --- p.29 / Chapter 2.4 --- Chemical composition of mushroom fiber material --- p.31 / Chapter 2.4.1 --- Monosaccharide composition of non-starch polysaccharides (NSP) --- p.31 / Chapter 2.4.1.1 --- Acid depolymerisation --- p.31 / Chapter 2.4.1.2 --- Neutral sugar derivatization --- p.31 / Chapter 2.4.1.3 --- Determination of neutral sugars by gas chromatography (GC) --- p.32 / Chapter 2.4.1.4 --- Uronic acid content --- p.32 / Chapter 2.4.2 --- Resistant starch content --- p.33 / Chapter 2.4.3 --- Residual protein content --- p.34 / Chapter 2.5 --- Fractionation of mushroom fiber material --- p.34 / Chapter 2.5.1 --- Solvent extraction --- p.34 / Chapter 2.5.2 --- Anion-exchange chromatography --- p.35 / Chapter 2.5.3 --- Gel permeation chromatography --- p.36 / Chapter 2.6 --- Structural analysis of mushroom fiber material --- p.37 / Chapter 2.6.1 --- Linkage analysis by methylation --- p.37 / Chapter 2.6.1.1 --- Preparation of methylsufinyl carbanion (Dimsyl) --- p.37 / Chapter 2.6.1.2 --- Preparation and dissolution of sample --- p.37 / Chapter 2.6.1.3 --- Methylation --- p.38 / Chapter 2.6.1.4 --- Hydrolysis --- p.38 / Chapter 2.6.1.5 --- Reduction and acetylation --- p.39 / Chapter 2.6.1.6 --- Determination of partially methylated alditol acetate (PMAA) by gas chromatograph-mass spectrometry (GC-MS) --- p.39 / Chapter 2.6.2 --- Fourier-transform infrared (FTIR) spectroscopy --- p.40 / Chapter CHAPTER THREE : --- RESULTS AND DISCUSSION --- p.41 / Chapter 3.1 --- Chemical composition of mushrooms --- p.41 / Chapter 3.1.1 --- Moisture content --- p.41 / Chapter 3.1.2 --- Carbohydrate content --- p.41 / Chapter 3.1.3 --- Protein content --- p.44 / Chapter 3.1.4 --- Amino acid profile --- p.44 / Chapter 3.1.5 --- Dietary fiber content --- p.48 / Chapter 3.1.6 --- Cell wall material --- p.53 / Chapter 3.1.7 --- Comparison of the yield and composition of TDF and CWM --- p.55 / Chapter 3.1.8 --- "Monosaccharide composition of the dietary fiber (TDF, IDF and SDF) and cell wall material (CWM)" --- p.57 / Chapter 3.2 --- Fractionation of TDF and CWM --- p.69 / Chapter 3.2.1 --- Solvent extraction --- p.69 / Chapter 3.2.2 --- Monosaccharide composition of solvent fractionated TDF and CWM --- p.71 / Chapter 3.2.3 --- Anion-exchange chromatography --- p.78 / Chapter 3.2.4 --- Gel permeation chromatography --- p.82 / Chapter 3.2.5 --- Monosaccharide composition of fractionated fiber material by anion-exchange chromatography --- p.84 / Chapter 3.3 --- Structural analysis --- p.86 / Chapter 3.3.1 --- Partially methylated alditol acetate (PMAA) --- p.86 / Chapter 3.3.1.1 --- Alkali-extracted water-soluble fractions of V. volvacea fiber material --- p.95 / Chapter 3.3.1.2 --- Alkali-extracted water-soluble fractions of P. sajor-caju fiber material --- p.99 / Chapter 3.3.1.3 --- Alkali-extracted water-soluble fractions of P. tuber-regium fiber material --- p.102 / Chapter 3.3.1.4 --- Alkali-extracted water-insoluble fractions of the mushroom fiber material --- p.106 / Chapter 3.3.1.5 --- Alkali- and acid- resistant fractions of the mushroom fiber material --- p.109 / Chapter 3.3.2 --- Infrared spectroscopy --- p.112 / Chapter 3.4 --- "β (l→3), (→4) glucan" --- p.119 / Chapter CHAPTER FOUR : --- CONCLUSION --- p.121 / REFERENCES --- p.125 / RELATED PUBLICATIONS --- p.137

Thesis (PhD. (Zoology)) --University of Limpopo, 2013 / Edible insects have been used as a nutritious food source by mankind for millennia, but in the modern era their use in more industrialised and western countries has dwindled. In the face of concern over the global food security crisis, scientists are urging investigation into edible insects as an alternate food. This study contributes to this global initiative by investigating entomophagy in the Blouberg area of the Limpopo Province, South Africa. The research develops a database of Blouberg edible insects, documents the importance of entomophagy to the people of Blouberg and for the wider community, and investigates aspects of the biology, ecology, socio-economics and nutritional value of a key species harvested in the area. Semi-structured questionnaires were carried out between 2007 and 2008 amongst households in the vicinity of Blouberg Mountain. Nearly 91% of the households in the Blouberg area consume insects. The most important reasons cited for consuming insects are that they are a traditional food, that they taste good and that they are a free food resource. Twenty eight species of edible insects were identified to at least genus level. Education was more important than income in influencing whether or not insects were consumed in a household. Households with lower education scores were more likely to consume insects than those with mid-level education scores. However, those with low income scores consumed a greater quantity of insects than those with higher scores. Similarly, those with low education scores consumed more insects than those with higher education scores. Pasture land was the area most preferred for collecting insects, with crop lands second in importance. Natural vegetation was not a preferred collecting habitat. Most households (78.57%) believe there has been a decline in edible insect consumption in recent years. According to the Blouberg insect collectors, edible insects are also on the decline in Blouberg and most households are unhappy about this. The lepidopteran, Hemijana variegata (bophetha), which was targeted for more in depth research, was found to be univoltine in the field, with caterpillars emerging in early November. The caterpillars feed predominantly on Canthium armatum and to a lesser extent on Pyrostria hystrix. They take four weeks to develop, burrowing into the soil to overwinter as pupae to emerge as adults in late spring. The development of the moth is profoundly influenced by temperature at all life stages and ceased below 17ºC and above 35ºC. Temperatures between 23ºC and 29ºC were most favourable for growth. The food value of the bophetha caterpillars was found to be high. The protein value of traditionally prepared caterpillars is 45.5%, with carbohydrates at 11.86 mg/100 g and fat at 19.75%. The caterpillars are not as rich in vitamins as fruit or vegetables, but compare favourably with beef. Traditionally prepared bophetha were found to be contaminated by two bacteria and one fungus, none of which are dangerously pathogenic to humans. Bophetha are traded between Blouberg villages at costs equivalent to other edible insects in South Africa (R10.19 per cup). Almost one third of Blouberg inhabitants sell bophetha, with this percentage decreasing to about 10% in poor seasons. Households collect between 3 and 3.5 litres of bophetha per season. Blouberg households are of the opinion that knowledge about edible insects is important enough that it should be included in formal education as a way of ensuring that the younger generation assimilates aspects of this knowledge despite cultural changes. The results of the study emphasise the importance of natural resource use with respect to edible insects in a marginalised community.

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The application of Fourier transform infrared (FTIR) spectroscopy in the assessment of oil quality and stability and the determination of the degree and type (cis or trans) of unsaturation of fats and oils was investigated. FTIR spectroscopy was shown to provide a rapid means of monitoring changes in oils undergoing oxidation or subjected to thermal stress. Absorption bands associated with common primary and secondary oxidation products were identified by relating them to those of spectroscopically representative reference compounds, and a quantitative approach based on the use of oils spiked with these reference compounds as calibration standards was proposed. A sample-handling accessory based on a heated 25-mum transmission flow cell and heated input and output lines was developed to facilitate the rapid analysis of oils and premelted fats in their neat form. Using this system, an FTIR edible oil analysis package was developed to simultaneously analyze for trans content, cis content, iodine value (IV), and saponification number (SN) of neat fats and oils, using partial-least-squares (PLS) calibrations based on pure triglycerides. An automated transmission-based peak height method for isolated trans isomer determination using the characteristic trans absorption band at 967 cm -1 in the spectrum of a neat fat or oil, ratioed against the spectrum of a trans-free oil, was also developed. A subsequent validation study involving the analysis of more than 100 oil samples demonstrated concurrence between the trans data obtained by the PLS and peak height FTIR methods as well as between IV results obtained by FTIR analysis and gas chromatography. In addition, the internal consistency of the IV, cis, and trans FTIR predictions provided strong experimental evidence that the FTIR edible oil analysis package measures all three parameters accurately. A PLS-based IV/trans method was developed for a heated single-bounce horizontal attenuated total reflectance (SB-HATR) sample-

The focus of this thesis is to develop pectin-based edible films for application of fruits and vegetables to extend their post harvest shelf life. Preliminary research demonstrated that edible coatings could effectively extend the shelf life of based avocado and peach. The respiration rate, moisture loss, firmness, chemical parameters and color changed in a lower rate in coated fruits as compared with the control. Pectin-based film formulations were then evaluated to identify the proper type and concentration of pectin, lipids and plasticizers in the film. The effects of pectin, beeswax and sorbitol concentration on water vapor permeability, mechanical properties and opacity of the films were then evaluated using response surface methodology to identify appropriate levels of different components. Results of studies on film structure revealed that water vapor permeability increased by pectin and sorbitol concentration and was decreased by beeswax concentration. Mechanical properties were mainly affected by pectin and sorbitol concentration. Beeswax was the most influential factor that affected opacity which increased with increasing beeswax concentration. / In order to successfully employ these films, their adsorption behavior, thermal and thermomechanical properties were evaluated as a function of moisture content and sorbitol concentration. The adsorption behavior was strongly influenced by sorbitol concentration. Moisture content and sorbitol concentration increased the films elongation at break, but decreased tensile strength, modulus of elasticity and Tg, and increased water vapor permeability of the films. Finally, avocado was coated with a pectin-based film and the associated quality changes were evaluated during storage. From storage studies, kinetic parameters (rate constants) and activation energy were quantified to help model the quality changes in avocado quality as function of storage temperature and time. Pectin-based coating resulted in slowing down the rate of quality changes in avocado at each storage temperature. In general, most changes were well described by some form of zero or first order rate. Temperature sensitivity of rate constant was adequately described by the Arrhenius model. / A hyperspectral imaging technique was also used to gather additional tools for following quality changes associated with stored avocados. Artificial neural network (ANN) concepts were evaluated as alternated models for predicting quality changes in coated and non-coated avocados during storage at different temperature. Modeling of quality changes in avocado indicated that compared to conventional mathematical models, ANN has more feasibility to predict of these changes. Models developed for firmness, weight loss and total color difference had better fitness than respiration rate. / Finally, the effect of coating on disease severity and different properties of avocados infected by Lasiodiplodia theobromae was studied. The coated fruits demonstrated slower rate of disease progress, respiration rate, softening and color changes. Respiration rate, firmness and color parameters were sensitive to coating and disease severity, and thus these parameters could successfully used to predict fruit quality from disease in coated and uncoated avocados.

Thesis (M. Env. St.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1999. / Includes bibliographical references (leaves 103-117).

Thesis (Master)--İzmir Institute of Technology, İzmir, 2005. / Keywords: Biopreservatives, antimicrobial enzymes, antioxidant proteins, edible films, functional packaging materials. Includes bibliographical references (leaves.88-101).