Changes in sensory quality of sterile cantaloupe dice stored in controlled atmospheres.

Diced cantaloupe flesh that was microbiologically sterile was prepared in order to study the physiological deterioration of fruit when stored under a range of controlled atmospheres at 4.5°C. Sterile fruit pieces were prepared by boiling whole melons for 3 min, then dicing aseptically. Storage atmospheres were in continuous flow and contained from 0 to 26% CO2 and 3.5 to 17% O2. Sensory assessments were carried out by a highly trained panel at 14-day intervals. Products that were acceptable for up to 28 days were obtained when the following 3 treatments were used: 6% CO2 and 6% O2; 9.5% CO2 and 3.5% O2; and 15% CO2 and 6% O2. Overall, treatment with 0, 19.5 or 26% CO2 (irrespective of O2 concn.) caused significant deterioration in sensory properties.

Establishment of an Australian mild onion industry - the sensory component

In recent years, there has been increasing interest from growers, merchants, supermarkets and consumers in the establishment of a national mild onion industry. Imperative to the success of the emergent industry is the application of the National Mild Onion Certification Scheme that will establish standards and recommendations to be met by growers to allow them to declare their product as certified mild onions. The use of sensory evaluation techniques has played an imperative role throughout the project timeline that has also included varietal evaluation, evaluation of current agronomic practices and correlation of chemical analysis data. Raw onion consumer acceptance testing on five different onion varieties established preferences amongst the varieties for odour, appearance, flavour, texture and overall and differences in the level of pungency and aftertaste perceived. Demographic information was obtained regarding raw and cooked onion use, frequency of consumption and responses to the idea of a mild, less pungent onion. Additionally, focus groups were conducted to further investigate consumer attitudes to onions. Currently, a trained onion panel is being established to evaluate several odour, flavour and aftertaste attributes. Sample assessments will be conducted in January 2004 and correlated with chemical analyses that will hopefully provide the corner-stone for the anticipated Certification Scheme.

Getting value out of your sensory testing - the difference from control test

Non-parametric difference tests such as triangle and duo-trio tests traditionally are used to establish differences or similarities between products. However they only supply the researcher with partial answers and often further testing is required to establish the nature, size and direction of differences. This paper looks at the advantages of the difference from control (DFC) test (also known as degree of difference test) and discusses appropriate applications of the test. The scope and principle of the test, panel composition and analysis of results are presented with the aid of suitable examples. Two of the major uses of the DFC test are in quality control and shelf-life testing. The role DFC takes in these areas and the use of other tests to complement the testing is discussed. Controls or standards are important in both these areas and the use of standard products, mental and written standards and blind controls are highlighted. The DFC test has applications in products where the duo-trio and triangle tests cannot be used because of the normal heterogeneity of the product. While the DFC test is a simple difference test it can be structured to give the researcher more valuable data and scope to make informed decisions about their product.

Variability in odour reception in the peripheral sensory system of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

Mixtures of single odours were used to explore the receptor response profile across individual antennae of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Seven odours were tested including floral and green-leaf volatiles: phenyl acetaldehyde, benzaldehyde, b-caryophyllene, limonene, a-pinene, 1-hexanol, 3Z-hexenyl acetate. Electroantennograms of responses to paired mixtures of odours showed that there was considerable variation in receptor tuning across the receptor field between individuals. Data from some moth antennae showed no additivity, which indicated a restricted receptor profile. Results from other moth antennae to the same odour mixtures showed a range of partial additivity. This indicated that a wider array of receptor types was present in these moths, with a greater percentage of the receptors tuned exclusively to each odour. Peripheral receptor fields show variation in the spectrum of response within a population (of moths) when exposed to high doses of plant volatiles. This may be related to recorded variation in host choice within moth populations as reported by other authors.

Exploring the potential of VIS-NIR spectroscopy to predict sensory properties of foods

Sensory analysis of food involves the measurement, interpretation and understanding of human responses to the properties of food perceived by the senses such as sight, smell, and taste (Cozzolino et al. 2005). It is important to have a quantitative means for assessing sensory properties in a reasonable way, to enable the food industry to rapidly respond to the changing demands of both consumers and the market. Aroma and flavour are among the most important properties for the consumer and numerous studies have been performed in attempts to find correlations between sensory qualities and objective instrumental measurements. Rapid, non-destructive instrumental methods such as near infrared spectroscopy (NIR) might be advantageous to predict quality of food and agricultural products due to the speed of analysis, minimum sample preparation and low cost. The advantages of such technologies are not only to assess chemical structures but also to build a spectrum, characteristic of the sample, which behaves as a “finger print”.

Growing banana prawns in prawn farm settlement ponds to utilise and help remove waste nutrients.

To assess their utility for profitable wastewater bioremediation, banana prawns, Penaeus (Fenneropenaeus) merguiensis (de Man), were stocked at low densities (1 – 5 m-2) and grown without supplemental feeding in five commercial-prawn-farm settlement ponds (0.3 to 6.0 ha). The prawns free-ranged in the variously designed ponds for 160 to 212 days after stocking as PL15. Survival estimates ranged from 12% to 60% with production of 50 – 528 kg ha-1. Over 1150 kg of marketable product was produced in the study. Exceptional growth was monitored at one farm where prawns reached an average size of 17g in 80 days. Nutrients in water flowing into (8 - 40 ML d-1) and out of the settlement pond at that farm were assessed twice weekly along with routine water quality measurements. Only small differences in water qualities were detected between waters running into and out of this settlement pond. Total nitrogen levels gradually increased from 1 - 1.5 mg L-1 early in the season to over 3 mg L-1 towards the end of the season. Total phosphorus levels similarly rose from 0.1 - 0.2 mg L-1 to 0.3 - 0.4 mg L-1 in the middle of the season, but fell to 0.2 – 0.3 mg L-1 towards the end when approximately 12,000 prawns were harvested with a total weight of 175 kg. No significant differences (P > 0.05) were detected in the overall acceptability of prawns harvested from each of the 5 settlement ponds in small-scale consumer sensory analyses. The prawns from settlement ponds were rated similarly to banana prawns grown with commercial diets at two other establishments. Microbiological analyses of prawns from all farms showed bacterial levels to be well within food-grade standards and lower than prawns produced in a normal growout pond. These results demonstrate that high quality food grade banana prawns can be produced in these wastewater treatment systems.

Mapping compositional parameters of cocoa to sensory profiles

This project will establish an innovative quantitative analytical technique which will assist the development of Queensland's cocoa industry through a better understanding of those components that can produce unique sensory and flavour profiles of cocoa products.

Shepard avocado sensory analysis

Avocados Australia has commissioned a study to evaluate whether the current dry matter maturity standards for Shepard avocado are reasonable, or whether they need to be refined. A sensory analysis program will be conducted from within the 2010 Shepard avocado season.

Sensory Systems in Sawfishes. 2. The Lateral Line.

The lateral line system allows elasmobranchs to detect hydrodynamic movements in their close surroundings. We examined the distribution of pit organs and lateral line canals in 4 species of sawfish (Anoxypristis cuspidata, Pristis microdon, P. clavata and P. zijsron). Pit organs could only be located in A. cuspidata, which possesses elongated pits that are lined by dermal denticles. In all 4 pristid species, the lateral line canals are well developed and were separated into regions of pored and non-pored canals. In all species the tubules that extend from pored canals form extensive networks. In A. cuspidata, P. microdon and P. clavata, the lateral line canals on both the dorsal and ventral surfaces of the rostrum possess extensively branched and pored tubules. Based on this morphological observation, we hypothesized that these 3 species do not use their rostrum to search in the substrate for prey as previously assumed. Other batoids that possess lateral line canals adapted to perceive stimuli produced by infaunal prey possess non-pored lateral line canals, which also prevent the intrusion of substrate particles. However, this hypothesis remains to be tested behaviourally in pristids. Lateral line canals located between the mouth and the nostrils are non-pored in all 4 species of sawfish. Thus this region is hypothesized to perceive stimuli caused by direct contact with prey before ingestion. Lateral line canals that contain neuromasts are longest in P. microdon, but canals containing neuromasts along the rostrum are longest in A. cuspidata.

Sensory Systems in Sawfishes. 1. The Ampullae of Lorenzini

The distribution and density of the ampullary electroreceptors in the skin of elasmobranchs are influenced by the phylogeny and ecology of a species. Sensory maps were created for 4 species of pristid sawfish. Their ampullary pores were separated into pore fields based on their innervation and cluster formation. Ventrally, ampullary pores are located in 6 areas (5 in Pristis microdon), covering the rostrum and head to the gills. Dorsally, pores are located in 4 areas (3 in P. microdon), which cover the rostrum, head and may extend slightly onto the pectoral fins. In all species, the highest number of pores is found on the dorsal and ventral sides of the rostrum. The high densities of pores along the rostrum combined with the low densities around the mouth could indicate that sawfish use their rostrum to stun their prey before ingesting it, but this hypothesis remains to be tested. The directions of ampullary canals on the ventral side of the rostrum are species specific. P. microdon possesses the highest number of ampullary pores, which indicates that amongst the study species this species is an electroreception specialist. As such, juvenile P. microdon inhabit low-visibility freshwater habitats.

Lexicon for the Sensory Description of Australian Native Plant Foods and Ingredients

Understanding and describing Australian flavor has proved to be a challenge for marketers of native foods because of the diversity of unique flavor signatures exhibited. Descriptive analysis techniques were applied, using a panel of 11 experienced judges, to define and articulate the sensory properties of 18 key commercial Australian native plant foods and ingredients including fruits, herbs and spices. Quantitative descriptive data were transformed into concise and accurate verbal descriptions for each of the species. The sensory language developed during the vocabulary development panel sessions was combined, categorized and ordered to develop a sensory lexicon specific for the genre. The language developed to describe the foods and ingredients was diverse and distinctly Australian including aromas such as musk, rosella, citrus and spiced tea to eucalypt, bush scrub, fresh beetroot and wheat biscuit. Practical Applications This work provides a clear, useful means of characterizing and accurately describing the flavors of Australian native plant foods and ingredients. This information has been communicated to the native food industry, chefs, formulators, food technologists and flavor experts, and provides knowledge that will assist the wider food industry to successfully develop flavor blends and produce food products from native food ingredients. It is anticipated that extension of this information to both the local and international food markets will stimulate a renewed interest in Australian native ingredients and open new market opportunities for the industry. The data developed by this research have also formed the basis of quality control targets for emerging native foods and ingredients.

Complexity of coffee flavor: A compositional and sensory perspective

For the consumer, flavor is arguably the most important aspect of a good coffee. Coffee flavor is extremely complex and arises from numerous chemical, biological and physical influences of cultivar, coffee cherry maturity, geographical growing location, production, processing, roasting and cup preparation. Not surprisingly there is a large volume of research published detailing the volatile and non-volatile compounds in coffee and that are likely to be playing a role in coffee flavor. Further, there is much published on the sensory properties of coffee. Nevertheless, the link between flavor components and the sensory properties expressed in the complex matrix of coffee is yet to be fully understood. This paper provides an overview of the chemical components that are thought to be involved in the flavor and sensory quality of Arabica coffee.

Impact of 1-methylcyclopropene treatment on the sensory quality of 'Bartlett' pear fruit

The ethylene biosynthesis inhibitor, 1-methylcyclopropene (1-MCP), has been commercially used to extend the storage life of European pear fruit and to allow shipment to distant markets. However, the influence of 1-MCP on the ability of fruit to ripen to an acceptable sensory quality has not been investigated in 'Bartlett' pear, one of the most aromatic of pear fruit. In the current study, early-, mid- and late-season 'Bartlett' pear fruit were treated with 0.6μLL-1 1-MCP at 0°C for 24h, 100μLL-1 ethylene at 20°C for 24h, or untreated before immediate transfer to 20°C for ripening until eating soft (13N firmness). Fruit from each treatment were subjected to objective and sensory quality evaluation once ripe. Sensory quality showed differences related to harvest maturity; the importance of harvest maturity depended on the treatment. Treatment with 1-MCP effectively slowed fruit ripening and therefore extended postharvest life, but also resulted in fully ripened pears with more desirable sensory traits, as compared with ethylene-treated and untreated pears. The enhanced sensory quality was related to higher sweetness, juiciness and pear aroma and reduced fermented aroma, gritty texture and tart taste. In addition, the sensory profiles of 1-MCP-treated pears were more stable among fruit from the three harvest dates than the ethylene-treated pears, which exhibited very different sensory profiles between early- and late-season fruits. © 2015 Elsevier B.V.

Innovating a consumer awareness of sweetpotato: industry, research and consumer adoption issues

In Australia, sweetpotato production has grown remarkably (1700%) in the last 16 years. Growers currently market 75 000 t per annum, worth $80-90 million at farm gate. The orange-fleshed cultivars are the most familiar to consumers, but other cultivars with varying flesh colour and properties also have potential for the consumer market. Given that Australian sweetpotato growers desire alternative cultivars to promote market demand, it is important to articulate the characteristics of sweetpotatoes that are most and least desirable for consumers. Research indicates that consumer acceptability of the new cultivar 'Evangeline' may assist sweetpotato growers and marketers in understanding the impact of both sensory properties, such as colour and the importance of flavour and texture of sweetpotatoes, and an awareness of the potential health benefits of sweetpotato consumption. In addition, whilst consumer preferences (regarding size, colour, texture, skin tone) and nutritional knowledge of sweet potato (regarding glycaemic index) is increasing, there is limited research investigating consumers understanding of health messages of sweetpotato attributes. This industry and consumer research review highlights the potential for promoting innovative strategies to improve adoption of new cultivars in the marketplace.