F. M. Scriven

Metabolism of geraniol by apples in relation to the development of storage breakdown

Abstract Geraniol was injected into the core of Jonathan apples susceptible to storage breakdown. It was rapidly metabolized to geranyl β- d -glucoside which was transported to the flesh and metabolized into other compounds. When geraniol was injected into the flesh and prevented from diffusing into the core area, metabolism of geraniol was completely inhibited. The results suggest that some factor associated with the apple seeds is involved in the formation of the glucoside and hence with the induction of breakdown.

Hot water dips for the control of pathological decay in sweet potatoes

Abstract Hot water dip treatments in the range 40–100°C for 2–240 s were investigated for the control of pathological decay in sweet potatoes ( Ipomea batatus (L.) Lam cultivar ‘L0323’). It was found that dipping roots at 90°C for 2 s, 80°C for 2, 4 or 10 s, 70°C for 10 s or 40°C for 120 s substantially delayed the time to initial rot without affecting respiration rate or weight loss.

An application of contextual evaluation to allow simultaneous food product development for domestic and export markets

Abstract Simultaneous food product development for domestic and export markets is a logical direction for the Australian food industry which tends to export surplus rather than develop products to suit specific export markets. The aim of this study was to use contextual evaluation of a range of meat products by Thai and Australian consumers, to identify common contexts of use for which products could be developed. Contextual attributes were elicited using the repertory grid technique and the most frequently occurring terms were compiled into a questionnaire used to profile the usage characteristics of the meat products. Thirty Thai and Thirty Australian respondents rated 18 meat products on 100-mm line scales to indicate how appropriate it would be to consume each product for each of the contexts listed. Line scales were anchored by the words never (at the left) and always (at the right). These data were subjected to principal component analysis. Six and four principal components were found to describe the underlying contextual dimensions for Thai and Australian respondents, respectively, but only the first two were used for further interpretation. ‘Social functions’ is the most important common situation underlying the uses of meat products by both groups of respondents. The meat products that are considered as most appropriate in this respect are fermented meat products and emulsion type meat products. Further parallel development of these types of product for the domestic (Australian) and export (Thai) markets may be appropriate.

Analysis of Hydroxybenzoic Acids by High Pressure Liquid Chromatography

Abstract Good separation of a range of hydroxybenzoic acids was achieved by HPLC on a μBondapak phenyl column using 5% v/v acetic acid in water as the eluting solvent.

Postharvest changes in abscisic acid levels in flesh tissue and seeds of Jonathan apples susceptible to storage breakdown

SummaryAnalysis of fruit and seed samples after periods from three to 16 weeks of storage showed that the abscisic acid level in the flesh was maximal early in storage, declining during 16 weeks at —1°C. A direct correlation between ABA level and later breakdown incidence was present early in storage, the correlation being greatest after five weeks, much earlier than the appearance of visible symptoms. In the seeds ABA was maximal after three weeks and then declined, being undetectable by 12 weeks. However, there was no significant correlation between seed ABA content and breakdown incidence. When early seed extracts were injected into fruit, breakdown incidence increased but the increase was unrelated to the fruit source of the seeds.

Consumer perceptions of bananas treated with ethylene or allowed to ripen naturally

Consumers evaluated the eating quality and appearance of commercially available (ethylene treated) bananas and bananas which were allowed to ripen naturally (without ethylene). Quantitative measures of sweetness, liking when eaten, ripe taste, softness, flesh yellowness, liking of skin colour and skin yellowness were collected for bananas at three different stages of ripeness as judged by skin colour. Whole and peeled bananas were provided separately. Multivariate analysis of the combined data revealed that consumers discriminate between fruit using liking of skin colour and softness. Consumers like the taste of ripe fruit, but like the appearance of unripe fruit. Consumers were also able to detect that at a certain stage of skin colour ripeness, ethylene treatment results in bananas with flesh ripeness out of phase with skin colour ripeness.

Pilot study of consumer wastage of horticultural produce

Abstract A pilot consumer survey was conducted to investigate the extent to which horticultural produce was wasted once it had been brought into the home. An overall wastage rate of 30% was found, comprising the following reasons for rejection — 16% trimmings, 7% physiological disorders, 2% pathological decay and 1% for each of mechanical damage, weight loss, senescence, inedible portions and others. It was also estimated that when physiological disorders occurred 89% of the produce was wasted; 83% when senescence occurred; 47% when weight loss occurred; 38% when pathological decay occurred; 35% when mechanical damage occurred; 25% when trimming occurred and 10% when a portion was considered inedible. The way this information could be used to adjust consumption statistics and interpret consumer behaviour is discussed.

Relation between germination of apple seeds and susceptibility of fruit to develop storage breakdown

SummaryApple seeds removed early in storage from fruits susceptible to breakdown were found to have a slower germination rate than those removed from less susceptible fruits. However, when the seeds were removed from fruits late in storage, germination was faster for seeds from fruits that were more susceptible to breakdown. It was also found that while the seeds remained inside the fruits germination was delayed.