Properties of ectin isolated from Lawulu (Crysophylum roxbergi G Don) and development of jam and fruit leather using Lawulu and pineapple

Lawulu fruit (Crysophylum roxberghi GDon) possess nutritional, medicinal and functional properties. However, it is less consumed due to its&nbsp; characteristic off flavour. The present study was carried out to investigate the potential of utilizing lawulu fruit for isolation of pectin and to develop jam and fruit leather. Products were evaluated based on physico-chemical and sensory properties.Pectin isolated fromf irm ripe lawuluf ruit using 0.1 M hydrochloric acid&nbsp; followed by 96% ethanol precipitation yielded 7. 3% pectin on wet weight basis and 26.1% on dry weight basis. The isolated pectin contained 0.74% ash, 0.02% acetyl content and 7.85% methoxyl content with equivalent weight 993.5. These values were comparable with commercial high methoxyl pectin. In addition, Iawulu pectin at 1.5% concentration formed a gel within 12-14 min in the presence of 68% sucrose and 0.5% citric acid.Jam was prepared by using Iawulu-pineapple ratio as 1:2, 1:1 and 2:1 respectively. The gel strength of jam (650 Brix and pH 3.1) at 0.35% commercial high methoxyl pectin was comparable with commercial mixed fruit jam. Sensory evaluation indicated a significant preference (p&lt;.05) for jam containing lawulu-pineapple ratio of 1:2 and 1.1 respectively overthe ratio of 2:1. With increased lawulu percentage both yellowness and lightness of jam increased significantly (p&lt;0.05).Fruit leather was prepared by changing lawulu-pineapple ratio as 1:2, 1:1 and 2:1 respectively with 20% sucrose, 0.3% citric acid, 0.05% pectin and 100 ppm potassium metabisulphite followed by drying at 65&plusmn;10C for 12-14 h. Sensory evaluation data revealed that changes in lawulu-pineapple ratio had no significant effect on taste, texture and overall quality of fruit leather.&nbsp;&nbsp; However, significant preference (p&lt;0.05) for colour was observed with increasing lawulu percentage. Both yellowness (b\u27 value) and lightness (L\u27value) of fruit leather were sign[icantly increased (p&lt;0.05) with increasing lawulu percentage.<br /

Preservation of fresh coconut gratings by hurdle technique

Hurdle technology employs the intelligent combination of different preservation factors to achieve mild but reliable preservation effects. Fresh coconut gratings treated with different combinations of hurdles such as acidulants, humectants, preservatives, antioxidants, a mild heat treatment and packaging were evaluated for changes in physicochemical and sensory properties. It is possible to preserve the grating for four weeks in laminated polythene packages at 5 degrees C in combination with 3% sodium chloride, 0.3% citric acid, 0.009% sodium citrate, 0.02% butylated hydroxyanisole.<br /

Trends in high pressure processing of foods : food quality and bioactive components

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

Extruded products with Fenugreek (Trigonella foenum-graecium) chickpea and rice: Physical properties, sensory acceptability and glycaemic index

The present study investigated the effects of fenugreek flour (Trigonella foenum-graecum) and debittered fenugreek polysaccharide (FenuLife&reg;) inclusion on the physical and sensory quality characteristics, and glycaemic index (GI) of chickpea&ndash;rice based extruded products. Based on preliminary evaluation with different proportions of chick pea and rice, a blend of 70:30 chickpea and rice was chosen as the control for further studies. The control blend, replaced with fenugreek flour at 2%, 5% and 10%, or fenugreek polysaccharide at 5%, 10%, 15% and 20%, was extruded at the optimum processing conditions as specified in the detailed study. The extruded products were evaluated for their physical (moisture retention, expansion, hardness, water solubility index (WSI) and water absorption index (WAI)), sensory (flavor, texture, color and overall acceptability) characteristics and in vitro GI to evaluate their suitability as extruded snack products.Due to the distinct bitter taste, inclusion of fenugreek flour was not acceptable at levels more than 2% in extruded chickpea based products. Addition of fenugreek polysaccharide resulted in slight reduction in radial expansion (P &lt; 0.05), while longitudinal expansion increased. WAI increased while WSI decreased compared to the control (P &lt; 0.05). The mean scores of sensory evaluation indicated that all products containing fenugreek polysaccharide up to 15% were within the acceptable range. There were no significant differences (P &gt; 0.05) between products containing 5&ndash;15% fenugreek polysaccharide in their color, flavor, texture and overall quality.Fenugreek, in the form of debittered polysaccharide (FenuLife&reg;) could be incorporated up to a level of 15% in a chickpea&ndash;rice blend to develop snack products of acceptable physical and sensory properties with low GI Index.<br /

Non-thermal food processing : impact on chemical, nutritional and bioactive components

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

Physical characteristics of extruded maize, finger millet and legume products

E

Inulin and maltodextrin can replace fat in baked savoury legume snacks

A baked yellow split pea cracker was developed with fat replacement (0%, 25%, 50%, 75% and 100%) using inulin, hydroxypropyl methylcellulose and maltodextrin. Effects of fat replacement on physical (water activity, moisture content, colour and hardness), nutritional properties and consumer acceptance (nine-point hedonic rating) of snacks were investigated. Water activity (0.15-0.32) and moisture (1.28-3.16%) readings were consistent, and products were considered shelf stable. High levels of fat replacement (100%) were detrimental to snack colour and hardness. Snacks with 75% fat replacement using inulin and maltodextrin received similar mean overall acceptability scores (6.40 &plusmn; 1.36 and 6.26 &plusmn; 1.37, respectively) to the control and a similar commercial product. These snacks were eligible to claim that they were a \u27good source\u27 of protein (requirement; &ge;10 g per serve) and an \u27excellent source\u27 of dietary fibre (requirement; &ge;7 g per serve) while providing \u27reduced\u27 fat content (&le;25% than reference food) based on the Australian Food Standards Code

Physical, nutritional and sensory properties of extruded banana, rice and green gram mixtures

E

Retention of essential amino acids during extrusion of protein and reducing sugars

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 &deg;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,&nbsp; tryptophan, threonine, and methionine were found to be significantly changed (P &lt; 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.<br /