Shane Olsson - Academia.edu (original) (raw)

Papers by Shane Olsson

New Zealand Plant Protection

New Caledonia exports limes to New Zealand and Australia each year. In 2011, a high pressure wash... more New Caledonia exports limes to New Zealand and Australia each year. In 2011, a high pressure washing (HPW) system was installed in an existing fresh lime grading line in La Tontouta, New Caledonia. Since then, fumigation of limes has decreased from 100% of shipments prior to 2011 to 5.8% in 2012 and 1.2% in 2013 (from 173 and 82 shipments respectively). This paper reports on trials undertaken over the last 2 years while installing, modifying, testing and commercially operating the HPW system for lime exports. Fruit quality and removal of pests (mainly Glover’s scale (Lepidosaphes gloverii) and mussel scale (Lepidosaphes beckii)) indicated that a 175 psi (1207 kPa) HPW treatment under a gantry of seven rows of two angled nozzles resulted in up to 97% removal of pests and >84% of heavily infested limes being clean of pests, with no adverse effect on fruit quality.

Advances in Horticultural Science

ABSTRACT

Gourmet and Health-Promoting Specialty Oils, 2009

New Zealand Journal of Forestry Science, 2015

Journal of the Science of Food and Agriculture, 2014

Improving apricot fruit quality delivered to consumers is key to ensuring a successful apricot in... more Improving apricot fruit quality delivered to consumers is key to ensuring a successful apricot industry. Previous studies have focused on effects of either soluble solids content (SSC) or fruit firmness on consumer preferences, and results have been equivocal. This study evaluated the effects of crop load and harvest maturity how they affected on fruit SSC and firmness, and on subsequent consumer preferences. SSC of apricots was an important factor only when fruit were firmer than 15 N and not immature. When fruit were softer than 15 N, SSC had little influence on consumer liking. In general, consumers preferred fruit that were grown on trees thinned to approximately 10-20% less than typical commercial crop loads and were harvested in a more mature condition. Consumers also preferred fruit that had a higher sugar/acid ratio or BrimA value, which is the °Brix - k × titratable acidity, where k is a constant that varies between species and cultivars depending on the specific acids and sugars present. High apricot flavour and juiciness were associated with greater sweetness. Management practices that increase fruit SSC and sugar/acid ratio, such as reducing crop load, will improve consumer satisfaction as long as fruit are harvested at an adequate maturity stage and are maintained in storage so that they do not soften too quickly. © 2014 Society of Chemical Industry.

Postharvest Biology and Technology, 2011

The effect of penetration speed on flesh firmness (FF) measurement by motorised penetrometer was ... more The effect of penetration speed on flesh firmness (FF) measurement by motorised penetrometer was examined for 'Hayward' (Actinidia deliciosa var. deliciosa) and 'Hort16A' (Actinidia chinensis Planch. var. chinensis) kiwifruit. Data was collected for penetration speeds varying from 4 to 40 mm s −1 using stored fruit of FF ∼10 N; a typical minimum FF threshold for export from New Zealand. Measurements were made on a number of instruments (Instron, GUSS FTA, HortPlus, TA.XTplus), using fruit from different orchards and in each of two different seasons. As expected, FF values increased with increasing penetration speed. A firmness-speed model was developed, based on the Maxwell rheological model for viscoelastic materials, which proved adequate in describing the FF data in terms of the effect of penetration speed. The effect of penetration speed was not adversely influenced by cultivar, season or instrument type. Within the range of fruit firmness examined -stored fruit below 20 N -it was concluded that the firmness-speed model could be successfully used to compare firmness values generated using instruments operating at different penetration speeds.

Postharvest Biology and Technology, 2012

The vase life of Asiatic lilies can be limited by leaf yellowing, which can be caused by exposure... more The vase life of Asiatic lilies can be limited by leaf yellowing, which can be caused by exposure to low light or temperature during winter growth or in storage. We examined the use of postharvest hot water treatments (HWTs) as a means of reducing leaf senescence in stored (4 • C for 2 weeks) and non-stored Asiatic hybrid lily 'Elite' (Lilium sp.). A range of HWTs (45-55 • C for 2.5 or 5 min) was applied to leaves on cut lily stems (but not flowers). Higher temperatures and the longer duration resulted in heat damage, but treatments of 50 • C for 5 min and 52.5 • C for 2.5 min were found to be optimal for minimising leaf yellowing with trace levels of heat damage for both non-stored and stored stems. The onset of yellowing was delayed by 3-4 d, and the occurrence of an unacceptable level of yellowing eliminated for up to 12 d (compared with <6 d for control stems). The physiological effects of these optimal HWTs were examined in terms of water uptake, chlorophyll fluorescence and chlorophyll degradation. Water uptake for optimal HWTs during shelf life was reduced by more than 50% of the control stems. Chlorophyll fluorescence of leaves on control stems showed a reduction in yield (F v /F o ) over time, which was more marked in lower than upper leaves (thus correlating with yellowing, which was more severe in the lower leaves). Although both optimal HWTs resulted in an initial reduction in yield, there was a recovery over time resulting in a yield that, by 12 d, was as high or significantly higher than control leaves (particularly for the lower leaves). All treatments showed a reduction in chlorophyll content (total, chlorophyll a and chlorophyll b), but control leaves had significantly lower levels after 7 d. HWTs show potential as a non-chemical, simple means of delaying leaf yellowing of Asiatic lilies and thus increasing vase life.

Postharvest Biology and Technology, 2010

In the export of 'Fuyu' persimmon, fruit are airfreighted at ambient temperatures, or seafreighte... more In the export of 'Fuyu' persimmon, fruit are airfreighted at ambient temperatures, or seafreighted at low temperatures using modified atmosphere (MA) packaging. Since persimmons are climacteric and ethylene sensitive, exposure to exogenous ethylene may accelerate natural softening at ambient temperature (e.g. airfreight) as well as aggravate chilling injury during coolstorage (e.g. seafreight). In the present work, the response of this cultivar to exogenous ethylene exposure was studied in four critical handling scenarios that might occur in a commercial chain. Non-packed fruit exposed to ethylene and then held at 20 • C (simulated airfreight) showed the greatest sensitivity to ethylene; fruit firmness and colour during shelf life were affected by even 1 d of exposure to 0.2 L L −1 ethylene. Lower sensitivity was observed when fruit were stored at 0 • C under MA conditions after ethylene exposure at 20 • C (simulated pre-packing exposure-seafreight), where fruit quality was not affected by exposures of 1 d at ≤1 L L −1 , and only slightly by 2 d at <0.5 L L −1 . When ethylene exposure was carried out at 0 • C after sealing fruit in MA bags (simulated post-packing exposure-seafreight), fruit showed the lowest sensitivity to ethylene, with only slight decrease of firmness with ethylene exposure at the end of the storage period, and no significant effect on exposure at the beginning of the storage period. Influence of the temperature of storage, temperature of exposure to ethylene, use of MA and timing of exposure during coolstorage in the response of the fruit to exogenous ethylene are discussed.

Postharvest Biology and Technology, 2013

ABSTRACT

Postharvest Biology and Technology, 2013

ABSTRACT This study was set up to identify critical maturity indices affecting storage potential ... more ABSTRACT This study was set up to identify critical maturity indices affecting storage potential of apricots and demonstrate the potential for using non-destructive measurements to segregate harvested crops for sequential marketing. Fruit of two apricot (Prunus armeniaca) cultivars (‘Clutha Gold’ and ‘Genevieve’) were harvested and stored for four weeks at 0 °C followed by four days of simulated shelf life at 20 °C. Fruit colour, acoustic firmness, impact firmness, flesh firmness (FF0), dry matter content and soluble solids content measured non-destructively at harvest were correlated to the flesh firmness measured at the end of refrigerated storage and simulated shelf life (FFFinal) through stepwise regression. The regression models indicated that FF0 is a predominant factor determining FFFinal. According to the exponential model describing the relationship between FF0 and FFFinal, ‘Genevieve’ and ‘Clutha Gold’ could be stored at 0 °C for four weeks if harvested at firmness above 47 or 56 N, respectively. Segregation of harvested crops according to FF0 estimated from VNIR would enable sequential marketing of fruit according to storage potential to reduce fruit loss.

Proceedings of the International Plant Propagators Society - 2012, 2013

New Zealand Plant Protection

New Caledonia exports limes to New Zealand and Australia each year. In 2011, a high pressure wash... more New Caledonia exports limes to New Zealand and Australia each year. In 2011, a high pressure washing (HPW) system was installed in an existing fresh lime grading line in La Tontouta, New Caledonia. Since then, fumigation of limes has decreased from 100% of shipments prior to 2011 to 5.8% in 2012 and 1.2% in 2013 (from 173 and 82 shipments respectively). This paper reports on trials undertaken over the last 2 years while installing, modifying, testing and commercially operating the HPW system for lime exports. Fruit quality and removal of pests (mainly Glover’s scale (Lepidosaphes gloverii) and mussel scale (Lepidosaphes beckii)) indicated that a 175 psi (1207 kPa) HPW treatment under a gantry of seven rows of two angled nozzles resulted in up to 97% removal of pests and >84% of heavily infested limes being clean of pests, with no adverse effect on fruit quality.

Advances in Horticultural Science

ABSTRACT

Gourmet and Health-Promoting Specialty Oils, 2009

New Zealand Journal of Forestry Science, 2015

Journal of the Science of Food and Agriculture, 2014

Improving apricot fruit quality delivered to consumers is key to ensuring a successful apricot in... more Improving apricot fruit quality delivered to consumers is key to ensuring a successful apricot industry. Previous studies have focused on effects of either soluble solids content (SSC) or fruit firmness on consumer preferences, and results have been equivocal. This study evaluated the effects of crop load and harvest maturity how they affected on fruit SSC and firmness, and on subsequent consumer preferences. SSC of apricots was an important factor only when fruit were firmer than 15 N and not immature. When fruit were softer than 15 N, SSC had little influence on consumer liking. In general, consumers preferred fruit that were grown on trees thinned to approximately 10-20% less than typical commercial crop loads and were harvested in a more mature condition. Consumers also preferred fruit that had a higher sugar/acid ratio or BrimA value, which is the °Brix - k × titratable acidity, where k is a constant that varies between species and cultivars depending on the specific acids and sugars present. High apricot flavour and juiciness were associated with greater sweetness. Management practices that increase fruit SSC and sugar/acid ratio, such as reducing crop load, will improve consumer satisfaction as long as fruit are harvested at an adequate maturity stage and are maintained in storage so that they do not soften too quickly. © 2014 Society of Chemical Industry.

Postharvest Biology and Technology, 2011

The effect of penetration speed on flesh firmness (FF) measurement by motorised penetrometer was ... more The effect of penetration speed on flesh firmness (FF) measurement by motorised penetrometer was examined for 'Hayward' (Actinidia deliciosa var. deliciosa) and 'Hort16A' (Actinidia chinensis Planch. var. chinensis) kiwifruit. Data was collected for penetration speeds varying from 4 to 40 mm s −1 using stored fruit of FF ∼10 N; a typical minimum FF threshold for export from New Zealand. Measurements were made on a number of instruments (Instron, GUSS FTA, HortPlus, TA.XTplus), using fruit from different orchards and in each of two different seasons. As expected, FF values increased with increasing penetration speed. A firmness-speed model was developed, based on the Maxwell rheological model for viscoelastic materials, which proved adequate in describing the FF data in terms of the effect of penetration speed. The effect of penetration speed was not adversely influenced by cultivar, season or instrument type. Within the range of fruit firmness examined -stored fruit below 20 N -it was concluded that the firmness-speed model could be successfully used to compare firmness values generated using instruments operating at different penetration speeds.

Postharvest Biology and Technology, 2012

The vase life of Asiatic lilies can be limited by leaf yellowing, which can be caused by exposure... more The vase life of Asiatic lilies can be limited by leaf yellowing, which can be caused by exposure to low light or temperature during winter growth or in storage. We examined the use of postharvest hot water treatments (HWTs) as a means of reducing leaf senescence in stored (4 • C for 2 weeks) and non-stored Asiatic hybrid lily 'Elite' (Lilium sp.). A range of HWTs (45-55 • C for 2.5 or 5 min) was applied to leaves on cut lily stems (but not flowers). Higher temperatures and the longer duration resulted in heat damage, but treatments of 50 • C for 5 min and 52.5 • C for 2.5 min were found to be optimal for minimising leaf yellowing with trace levels of heat damage for both non-stored and stored stems. The onset of yellowing was delayed by 3-4 d, and the occurrence of an unacceptable level of yellowing eliminated for up to 12 d (compared with <6 d for control stems). The physiological effects of these optimal HWTs were examined in terms of water uptake, chlorophyll fluorescence and chlorophyll degradation. Water uptake for optimal HWTs during shelf life was reduced by more than 50% of the control stems. Chlorophyll fluorescence of leaves on control stems showed a reduction in yield (F v /F o ) over time, which was more marked in lower than upper leaves (thus correlating with yellowing, which was more severe in the lower leaves). Although both optimal HWTs resulted in an initial reduction in yield, there was a recovery over time resulting in a yield that, by 12 d, was as high or significantly higher than control leaves (particularly for the lower leaves). All treatments showed a reduction in chlorophyll content (total, chlorophyll a and chlorophyll b), but control leaves had significantly lower levels after 7 d. HWTs show potential as a non-chemical, simple means of delaying leaf yellowing of Asiatic lilies and thus increasing vase life.

Postharvest Biology and Technology, 2010

In the export of 'Fuyu' persimmon, fruit are airfreighted at ambient temperatures, or seafreighte... more In the export of 'Fuyu' persimmon, fruit are airfreighted at ambient temperatures, or seafreighted at low temperatures using modified atmosphere (MA) packaging. Since persimmons are climacteric and ethylene sensitive, exposure to exogenous ethylene may accelerate natural softening at ambient temperature (e.g. airfreight) as well as aggravate chilling injury during coolstorage (e.g. seafreight). In the present work, the response of this cultivar to exogenous ethylene exposure was studied in four critical handling scenarios that might occur in a commercial chain. Non-packed fruit exposed to ethylene and then held at 20 • C (simulated airfreight) showed the greatest sensitivity to ethylene; fruit firmness and colour during shelf life were affected by even 1 d of exposure to 0.2 L L −1 ethylene. Lower sensitivity was observed when fruit were stored at 0 • C under MA conditions after ethylene exposure at 20 • C (simulated pre-packing exposure-seafreight), where fruit quality was not affected by exposures of 1 d at ≤1 L L −1 , and only slightly by 2 d at <0.5 L L −1 . When ethylene exposure was carried out at 0 • C after sealing fruit in MA bags (simulated post-packing exposure-seafreight), fruit showed the lowest sensitivity to ethylene, with only slight decrease of firmness with ethylene exposure at the end of the storage period, and no significant effect on exposure at the beginning of the storage period. Influence of the temperature of storage, temperature of exposure to ethylene, use of MA and timing of exposure during coolstorage in the response of the fruit to exogenous ethylene are discussed.

Postharvest Biology and Technology, 2013

ABSTRACT

Postharvest Biology and Technology, 2013

ABSTRACT This study was set up to identify critical maturity indices affecting storage potential ... more ABSTRACT This study was set up to identify critical maturity indices affecting storage potential of apricots and demonstrate the potential for using non-destructive measurements to segregate harvested crops for sequential marketing. Fruit of two apricot (Prunus armeniaca) cultivars (‘Clutha Gold’ and ‘Genevieve’) were harvested and stored for four weeks at 0 °C followed by four days of simulated shelf life at 20 °C. Fruit colour, acoustic firmness, impact firmness, flesh firmness (FF0), dry matter content and soluble solids content measured non-destructively at harvest were correlated to the flesh firmness measured at the end of refrigerated storage and simulated shelf life (FFFinal) through stepwise regression. The regression models indicated that FF0 is a predominant factor determining FFFinal. According to the exponential model describing the relationship between FF0 and FFFinal, ‘Genevieve’ and ‘Clutha Gold’ could be stored at 0 °C for four weeks if harvested at firmness above 47 or 56 N, respectively. Segregation of harvested crops according to FF0 estimated from VNIR would enable sequential marketing of fruit according to storage potential to reduce fruit loss.

Proceedings of the International Plant Propagators Society - 2012, 2013