On the Fluxus Group OPEN FLUXUS I started a small group Strawberry Fluxus House, in which Claudio Romeo added this image. Very funny!
Friday, February 29, 2008
The Beatles - Strawberry Fields Forever
Released on November 27, 1967
From the Magical Mystery Tour album
Written by John Lennon and Paul McCartney
Lyrics:
Let me take you down, cos I'm going to Strawberry Fields
Nothing is real and nothing to get hung about
Strawberry Fields forever
Living is easy with eyes closed
Misunderstanding all you see
It's getting hard to be someone but it all works out
It doesn't matter much to me
Let me take you down, cos I'm going to Strawberry Fields
Nothing is real and nothing to get hung about
Strawberry Fields forever
No one I think is in my tree
I mean it must be high or low
That is you can't you know tune in but it's all right
That is I think it's not too bad
Let me take you down, cos I'm going to Strawberry Fields
Nothing is real and nothing to get hung about
Strawberry Fields forever
Always, no sometimes, think it's me
But you know I know when it's a dream
I think I know I mean a "Yes" but it's all wrong
That is I think I disagree
Let me take you down, cos I'm going to Strawberry Fields
Nothing is real and nothing to get hung about
Strawberry Fields forever
Strawberry Fields forever
Strawberry Fields forever
[Cranberry sauce...]
From the Magical Mystery Tour album
Written by John Lennon and Paul McCartney
Lyrics:
Let me take you down, cos I'm going to Strawberry Fields
Nothing is real and nothing to get hung about
Strawberry Fields forever
Living is easy with eyes closed
Misunderstanding all you see
It's getting hard to be someone but it all works out
It doesn't matter much to me
Let me take you down, cos I'm going to Strawberry Fields
Nothing is real and nothing to get hung about
Strawberry Fields forever
No one I think is in my tree
I mean it must be high or low
That is you can't you know tune in but it's all right
That is I think it's not too bad
Let me take you down, cos I'm going to Strawberry Fields
Nothing is real and nothing to get hung about
Strawberry Fields forever
Always, no sometimes, think it's me
But you know I know when it's a dream
I think I know I mean a "Yes" but it's all wrong
That is I think I disagree
Let me take you down, cos I'm going to Strawberry Fields
Nothing is real and nothing to get hung about
Strawberry Fields forever
Strawberry Fields forever
Strawberry Fields forever
[Cranberry sauce...]
How to Keep Strawberries Fresh
People often want to know the best way to keep strawberries fresh. From our studies, we have found the best method to be removing all of the moldy or damaged ones and placing the good strawberries in the refridgerator in layers separated by paper towels inside a plastic container or sealed bag. This works great for short term storage- up to 3 days.
For anything longer than that, the strawberries will need to be frozen in a sealed plastic bag. Whatever storage method you use, do not wash the strawberries before storing them. Wait until you plan to eat them to rinse them off to ensure freshness.
source: http://www.strawberries.com/
For anything longer than that, the strawberries will need to be frozen in a sealed plastic bag. Whatever storage method you use, do not wash the strawberries before storing them. Wait until you plan to eat them to rinse them off to ensure freshness.
source: http://www.strawberries.com/
Wednesday, February 27, 2008
Monday, February 25, 2008
Growing Strawberries
Types
June bearing or spring bearing, everbearing and day neutral are the three types of strawberries grown in Illinois. Fruits of day neutral plants and everbearers are usually smaller than June-bearers fruit.
June bearing strawberries produce a crop during a two-to-three week period in the spring. June-bearers produce flowers, fruits and runners. They are classified into early, mid-season and late varieties.
Everbearing strawberries produce three periods of flowers and fruit during the spring, summer and fall. Everbearers do not produce many runners.
Day neutral strawberries will produce fruit throughout the growing season. These strawberries produce just a few runners.
Everbearing and day neutral strawberries are great for gardeners who have limited space. They can be grown in terraced beds, barrels or pyramids. They can also be used as an edging plant or a groundcover.
Strawberry Varieties
Strawberry varieties should be selected on the basis of dessert quality; preserving quality; disease resistance and season of maturation.
Strawberry cultivars for Illinois, listed by season from earliest to latest within groups and disease resistance
When to Plant
Plant strawberries as soon as the ground can be worked in the spring. This is usually in March or April allowing the plants to become well established before the hot weather arrives. Do not work the soil if it is wet. Wait a few days until it dries.
Planting Depth
Try to plant strawberries on a cloudy day or during the late afternoon. Set the strawberry plant in the soil so that the soil is just covering the tops of the roots. Do not cover the crown. After four or five weeks, the plants will produce runners and new daughter plants.
The center plant is set correctly, with the soil just covering the tops of the roots. The plant on the left is set too shallow; the plant on the right too deep.
Planting Systems
Matted Row Systems
This system is the best for growing June-bearing cultivars. In this system, the strawberry plants should be set eighteen to thirty inches apart in rows three to four feet apart. Daughter plants are allowed to root freely to become a matted row no wider than two feet.
Spaced-Row Systems
This system limits the number of daughter plants that grow from a mother plant. The mother plants are set eighteen to thirty inches apart in rows three to four feet apart. The daughter plants are spaced to root no closer than four inches apart. All other runners are pulled or cut from the mother plants. Even though more care is needed under this system, advantages include higher yields, larger berries and fewer disease problems.
Hill System
This is the best system for growing day-neutral and everbearing strawberries. In this system all the runners are removed so only the original mother plant remains. Removing the runners causes the mother plant to develop more crowns and flower stalks. Multiple rows are arranged in groups of two, three or four plants with a two foot walkway between each group of rows. Plants are set about one foot apart in multiple rows. During the first two or three weeks of growth, the planting should be weeded; then the bed should be mulched.
General Care
Strawberries are among the most widely grown fruit in the home garden. Strawberries prefer a well drained soil, high in organic matter. They need full sun for the highest yields, at least 6 hours per day. Do not plant strawberries where peppers, tomatoes, eggplant and potatoes have been grown. These plants could harbor verticillium wilt, a serious strawberry disease. Strawberries need about one inch of water per week during the growing season.
Blossom Removal
During the first growing season, remove flowers of June-bearing strawberries as soon as they appear. Removing the flowers promotes root and runner development thereby insuring a large crop the following year.
For everbearing and day-neutral strawberries, remove the flowers until the end of June and then after that date allow the flowers to remain to set fruit for a summer/fall harvest.
Fertilization
Before planting apply one pound per 100 square feet of a 10-10-10 fertilizer and dig into soil at least six to eight inches deep. After the first harvest in the second season strawberries should be fertilized after renovation in July. Water the fertilizer in to get it down to the root zone. This application is made to keep the plants in a vigorous condition and to promote new growth causing the development of more fruit buds. Do not over fertilize. Overfertilization will cause excessive vegetative growth, reduce yields; increase losses from frost and foliar disease and result in winter injury.
Mulching
Strawberries are very susceptible to frosts in the spring. Mulches that have covered the plants during the winter months should be removed in the early spring but should be left in the aisles to cover the blossoms in the spring when frost is predicted. Old blankets or sheets can be used for protection against frost. Spun bond material such as Reemay or row covers will protect strawberry plantings down to temperatures of about 23°-25°F. In the fall between mid-November and mid-December in Illinois but before temperatures drop below 20 degrees; apply a straw mulch three to four inches deep over the rows. This mulch will protect the plants from cold temperatures that can kill the buds and injure roots and crowns. Remove the mulch in the spring when the strawberry leaves show yellow. Leave some of the mulch around the plants to keep the fruit from soil contact and to conserve soil moisture.
Renovation
Renovation is an important part of strawberry care. In order to insure good fruit production, June-bearing strawberries grown in the matted row system should be renovated every year right after harvest. A strawberry patch will continue to be productive for three to four years as long as the planting is maintained. The first step in the renovation process is to mow the old foliage with a mower, cutting off the leaves about one inch above the crowns. Rake the leaves and if disease-free, compost or incorporate into the soil. Fertilize with one pound of a 10-10-10 fertilizer per 100 square feet. Narrow the rows to six to twelve inches wide by spading, hoeing or rototilling. Remove all weeds. Thin the plants in the narrowed row to 4 to 6 inches between plants. Water with one inch of water per week to promote growth and to make new runners for next year's crop.
June bearing or spring bearing, everbearing and day neutral are the three types of strawberries grown in Illinois. Fruits of day neutral plants and everbearers are usually smaller than June-bearers fruit.
June bearing strawberries produce a crop during a two-to-three week period in the spring. June-bearers produce flowers, fruits and runners. They are classified into early, mid-season and late varieties.
Everbearing strawberries produce three periods of flowers and fruit during the spring, summer and fall. Everbearers do not produce many runners.
Day neutral strawberries will produce fruit throughout the growing season. These strawberries produce just a few runners.
Everbearing and day neutral strawberries are great for gardeners who have limited space. They can be grown in terraced beds, barrels or pyramids. They can also be used as an edging plant or a groundcover.
Strawberry Varieties
Strawberry varieties should be selected on the basis of dessert quality; preserving quality; disease resistance and season of maturation.
Strawberry cultivars for Illinois, listed by season from earliest to latest within groups and disease resistance
When to Plant
Plant strawberries as soon as the ground can be worked in the spring. This is usually in March or April allowing the plants to become well established before the hot weather arrives. Do not work the soil if it is wet. Wait a few days until it dries.
Planting Depth
Try to plant strawberries on a cloudy day or during the late afternoon. Set the strawberry plant in the soil so that the soil is just covering the tops of the roots. Do not cover the crown. After four or five weeks, the plants will produce runners and new daughter plants.
The center plant is set correctly, with the soil just covering the tops of the roots. The plant on the left is set too shallow; the plant on the right too deep.
Planting Systems
Matted Row Systems
This system is the best for growing June-bearing cultivars. In this system, the strawberry plants should be set eighteen to thirty inches apart in rows three to four feet apart. Daughter plants are allowed to root freely to become a matted row no wider than two feet.
Spaced-Row Systems
This system limits the number of daughter plants that grow from a mother plant. The mother plants are set eighteen to thirty inches apart in rows three to four feet apart. The daughter plants are spaced to root no closer than four inches apart. All other runners are pulled or cut from the mother plants. Even though more care is needed under this system, advantages include higher yields, larger berries and fewer disease problems.
Hill System
This is the best system for growing day-neutral and everbearing strawberries. In this system all the runners are removed so only the original mother plant remains. Removing the runners causes the mother plant to develop more crowns and flower stalks. Multiple rows are arranged in groups of two, three or four plants with a two foot walkway between each group of rows. Plants are set about one foot apart in multiple rows. During the first two or three weeks of growth, the planting should be weeded; then the bed should be mulched.
General Care
Strawberries are among the most widely grown fruit in the home garden. Strawberries prefer a well drained soil, high in organic matter. They need full sun for the highest yields, at least 6 hours per day. Do not plant strawberries where peppers, tomatoes, eggplant and potatoes have been grown. These plants could harbor verticillium wilt, a serious strawberry disease. Strawberries need about one inch of water per week during the growing season.
Blossom Removal
During the first growing season, remove flowers of June-bearing strawberries as soon as they appear. Removing the flowers promotes root and runner development thereby insuring a large crop the following year.
For everbearing and day-neutral strawberries, remove the flowers until the end of June and then after that date allow the flowers to remain to set fruit for a summer/fall harvest.
Fertilization
Before planting apply one pound per 100 square feet of a 10-10-10 fertilizer and dig into soil at least six to eight inches deep. After the first harvest in the second season strawberries should be fertilized after renovation in July. Water the fertilizer in to get it down to the root zone. This application is made to keep the plants in a vigorous condition and to promote new growth causing the development of more fruit buds. Do not over fertilize. Overfertilization will cause excessive vegetative growth, reduce yields; increase losses from frost and foliar disease and result in winter injury.
Mulching
Strawberries are very susceptible to frosts in the spring. Mulches that have covered the plants during the winter months should be removed in the early spring but should be left in the aisles to cover the blossoms in the spring when frost is predicted. Old blankets or sheets can be used for protection against frost. Spun bond material such as Reemay or row covers will protect strawberry plantings down to temperatures of about 23°-25°F. In the fall between mid-November and mid-December in Illinois but before temperatures drop below 20 degrees; apply a straw mulch three to four inches deep over the rows. This mulch will protect the plants from cold temperatures that can kill the buds and injure roots and crowns. Remove the mulch in the spring when the strawberry leaves show yellow. Leave some of the mulch around the plants to keep the fruit from soil contact and to conserve soil moisture.
Renovation
Renovation is an important part of strawberry care. In order to insure good fruit production, June-bearing strawberries grown in the matted row system should be renovated every year right after harvest. A strawberry patch will continue to be productive for three to four years as long as the planting is maintained. The first step in the renovation process is to mow the old foliage with a mower, cutting off the leaves about one inch above the crowns. Rake the leaves and if disease-free, compost or incorporate into the soil. Fertilize with one pound of a 10-10-10 fertilizer per 100 square feet. Narrow the rows to six to twelve inches wide by spading, hoeing or rototilling. Remove all weeds. Thin the plants in the narrowed row to 4 to 6 inches between plants. Water with one inch of water per week to promote growth and to make new runners for next year's crop.
Strawberry Historical Facts
Strawberries are thought to have been cultivated in ancient Rome. The strawberry, as we know it, was originally grown in northern Europe, but species are also found in Russia, Chile, and the United States. The berries seem to be strewn among the leaves of the plant. The plant first had the name strewberry, which later was changed to strawberry. In France strawberries were cultivated in the 13th Century for useas a medicinal herb.
Historical Medicinal Uses of Fragaria Vesca (Alpine Strawberry):It is said that the leaves, roots and fruits of this variety of strawberry were used for a digestive or skin tonic. Internally, the berry was used for diarrhoea and digestive upset, while the leaves and the roots were used for gout. Externally, it was used for sunburn and skin blemishes, and the fruit juice was used for discoloured teeth.
The first American species of strawberries was cultivated about 1835. The first important American variety, the Hoveg, was grown in 1834, in Massachusetts. The hybrid variety was developed in France. The strawberry is considered one of the most important small fruits grown in the Western Hemisphere. Today every state in the United States and every province in Canada grows the strawberry plant.
Historical Medicinal Uses of Fragaria Vesca (Alpine Strawberry):It is said that the leaves, roots and fruits of this variety of strawberry were used for a digestive or skin tonic. Internally, the berry was used for diarrhoea and digestive upset, while the leaves and the roots were used for gout. Externally, it was used for sunburn and skin blemishes, and the fruit juice was used for discoloured teeth.
The first American species of strawberries was cultivated about 1835. The first important American variety, the Hoveg, was grown in 1834, in Massachusetts. The hybrid variety was developed in France. The strawberry is considered one of the most important small fruits grown in the Western Hemisphere. Today every state in the United States and every province in Canada grows the strawberry plant.
Sunday, February 24, 2008
Strawberry News
Strawberry News
Yahoo! News Search Results for Strawberries
Going the way of the strawberries (Merced Sun-Star) Strawberry fields forever.
Take Advantage Of The Versatility Of Strawberries (The Tampa Tribune) It's time to pay our respects to that bright-red, heart-shaped orb that delights: the strawberry.
Bel Air's tasty tradition (Baltimore Sun) Chocolate Festival to offer favorites, new confections Hundreds of chocolate lovers will descend upon downtown Bel Air on Saturday.
Divorcees party it up in Las Vegas (Los Angeles Times) The newly divorced toast their freedom -- and trash their ex-spouses -- at ever more elaborate gatherings in the nation's party capital. For parting partners, Las Vegas can be the Shangri-La of the quickie divorce. It takes only six weeks to no-fault freedom, and if you know how to play the game, it can take as few as 16 days.
Eat Your Garden Edible ornamentals offer a feast for more than the eyes (Seattle Times) by Valerie Easton IT'S NEARLY TIME to plant, and not just primroses and hellebores and sweet peas. This year the excitement seems to be...
Off the rack: Entertainment (Toronto Star) Cover: Well, isn't that just the saddest thing ever? Britney's unfortunate(-looking) children aren't even allowed to talk to her on the phone anymore. Kevin Federline is all kinds of concerned about her being a bad influence.
SCHOOL MENUS (Bradenton Herald) Elementary school
Project to document braceros' stories (Ventura County Star) CSU Channel Islands is teaming with the Smithsonian Institution to document the lives of braceros who once worked in Ventura County's fields and citrus orchards.
Southern HospitalityMystic society hosts 61st annual Valentine Ball (Montgomery Advertiser) Of all the celebrations for sweethearts last week, the Maskers 61st annual Valentine Ball was the most elaborate showcase in the River Region.
Deals: Omni Hotels (The Record) The deal: Get Your Glam On package at Omni Hotels nationwide and in Canada and Mexico. Gather your friends for a weekend of fun at one of the 31 participating hotels offering this girls-only package.
Yahoo! News Search Results for Strawberries
Going the way of the strawberries (Merced Sun-Star) Strawberry fields forever.
Take Advantage Of The Versatility Of Strawberries (The Tampa Tribune) It's time to pay our respects to that bright-red, heart-shaped orb that delights: the strawberry.
Bel Air's tasty tradition (Baltimore Sun) Chocolate Festival to offer favorites, new confections Hundreds of chocolate lovers will descend upon downtown Bel Air on Saturday.
Divorcees party it up in Las Vegas (Los Angeles Times) The newly divorced toast their freedom -- and trash their ex-spouses -- at ever more elaborate gatherings in the nation's party capital. For parting partners, Las Vegas can be the Shangri-La of the quickie divorce. It takes only six weeks to no-fault freedom, and if you know how to play the game, it can take as few as 16 days.
Eat Your Garden Edible ornamentals offer a feast for more than the eyes (Seattle Times) by Valerie Easton IT'S NEARLY TIME to plant, and not just primroses and hellebores and sweet peas. This year the excitement seems to be...
Off the rack: Entertainment (Toronto Star) Cover: Well, isn't that just the saddest thing ever? Britney's unfortunate(-looking) children aren't even allowed to talk to her on the phone anymore. Kevin Federline is all kinds of concerned about her being a bad influence.
SCHOOL MENUS (Bradenton Herald) Elementary school
Project to document braceros' stories (Ventura County Star) CSU Channel Islands is teaming with the Smithsonian Institution to document the lives of braceros who once worked in Ventura County's fields and citrus orchards.
Southern HospitalityMystic society hosts 61st annual Valentine Ball (Montgomery Advertiser) Of all the celebrations for sweethearts last week, the Maskers 61st annual Valentine Ball was the most elaborate showcase in the River Region.
Deals: Omni Hotels (The Record) The deal: Get Your Glam On package at Omni Hotels nationwide and in Canada and Mexico. Gather your friends for a weekend of fun at one of the 31 participating hotels offering this girls-only package.
Internet Firm
Nieuwe website voor IUCN NL
Het Amsterdamse internetbureau Strawberries heeft een geheel nieuwe website ontwikkeld voor IUCN NL, het Nederlandse comité van de natuurbeschermingsorganisatie International Union for the Conservation of Nature (IUCN).
Strawberries ontwerp van de nieuwe website van het IUCN NL presenteert alle informatie duidelijker en toegankelijker aan de gebruiker. De website kent daarnaast veel meer mogelijkheden dan de oude versie. Zo ontsluit een uitgebreid zoekfilter de projectendatabase Pluriform en maakt de website de samenwerking voor alle IUCN-units eenvoudiger door een groot aantal koppelingen. De website wordt centraal beheerd met een nieuw content managementsysteem.
Het Amsterdamse internetbureau Strawberries heeft een geheel nieuwe website ontwikkeld voor IUCN NL, het Nederlandse comité van de natuurbeschermingsorganisatie International Union for the Conservation of Nature (IUCN).
Strawberries ontwerp van de nieuwe website van het IUCN NL presenteert alle informatie duidelijker en toegankelijker aan de gebruiker. De website kent daarnaast veel meer mogelijkheden dan de oude versie. Zo ontsluit een uitgebreid zoekfilter de projectendatabase Pluriform en maakt de website de samenwerking voor alle IUCN-units eenvoudiger door een groot aantal koppelingen. De website wordt centraal beheerd met een nieuw content managementsysteem.
MilkShake
Strawberry (soy)milkshake
serves 2
500g fresh strawberries (I used Mara des bois, which are very tasty and rather sweet)
400ml soy milk, ice cold
Wash the strawberries and put the in a food mixer. Add the soymilk and blitz for a minute or so.
Put in glasses and top with fresh strawberries.
Drink as soon as it’s ready.
serves 2
500g fresh strawberries (I used Mara des bois, which are very tasty and rather sweet)
400ml soy milk, ice cold
Wash the strawberries and put the in a food mixer. Add the soymilk and blitz for a minute or so.
Put in glasses and top with fresh strawberries.
Drink as soon as it’s ready.
Friday, February 15, 2008
Thursday, February 14, 2008
Fuzz-Free Strawberries
Fuzz-free strawberries forecast with new food safety treatment
WEST LAFAYETTE, Ind. - Open up a pint of strawberries from the grocery store, and more often than not you'll find a fuzzy berry or two in the mix. A blast of chlorine dioxide gas, however, promises to not only keep those berries fuzz-free, but also to kill off harmful bacteria living on their surface more efficiently than methods currently used by the food industry, say Purdue University researchers.
"Strawberries are tricky," said Rich Linton, professor of food science and one of the leaders of the current study on decontaminating strawberries. "They're notoriously difficult to clean, and their surface composition actually encourages bugs to grow."
Those bugs can include potentially lethal bacteria, such as E. coli, as well as viruses including hepatitis A, which caused an outbreak linked to frozen strawberries in 1996.
"The issue with strawberries is that they're easily contaminated," Linton said. "They're grown in close association with soil, where they may pick up pathogens such as E. coil from manure-based fertilizers, and they're hand-picked, providing another avenue for contamination."
Linton and his colleagues at Purdue's Center for Food Safety Engineering, who already have demonstrated the efficacy of using chlorine dioxide gas to kill pathogens on the surface of apples and green peppers, have shown the treatment also removes significantly higher levels of pathogens than the current industry-standard chlorinated water rinse.
Linton's study, published in the current issue of the Journal of Food Protection, compares two different chlorine dioxide treatments, called "batch processing" and "continuous processing." Both treatments provide greater than a 5-log, or 99.999 percent, reduction in the numbers of E. coli and Listeria monocytogenes on strawberry surfaces.
Food safety experts assess decontamination efficiency with a measurement called "log reduction," which indicates how much contamination can be reduced after a decontamination treatment. A log, or logarithm, is a power of ten; thus a 1-log reduction is a 90 percent reduction; a 2-log reduction is a 99 percent reduction, and a 5-log reduction is a 99.999 percent reduction.
While current methods for removing pathogens on strawberries yield about a 2.5 log reduction in bacteria levels, the Food and Drug Administration has stated produce treatments should achieve a 5-log reduction in pathogens.
Not only does Linton's treatment significantly reduce the number of potentially harmful pathogens growing on strawberries, it also extends their shelf life without sacrificing quality attributes such as color and taste.
"The berries last a lot longer after this treatment-in fact, we've had strawberries in the refrigerator for more than six weeks with no mold growth," Linton said.
"If this process can give consumers even one or two more days before the strawberries they buy get fuzzy, that's huge. Think about it - how many strawberries do you have to throw away in a pint? If we could reduce that number, it would be a great advantage for consumers and the industry."
The two methods Linton used differ in the way the berries are exposed to the chlorine dioxide. In a batch system, the strawberries are placed in a sealed container, and a set amount of chlorine dioxide gas is applied once and then allowed to remain in the chamber for a period of time. Continuous treatment involves constant delivery of gas into the chamber over time.
Batch treatment required higher concentrations of chlorine dioxide treatment for longer amounts of time than continuous treatment, but both methods achieved more than a 5-log reduction in pathogens, Linton said.
He found that either 30 minutes of batch treatment, or 10 minutes of continuous treatment, produced effective levels of decontamination.
Linton's team currently has funding through the United States Department of Agriculture to scale up this technology and further develop it for use by the food industry.
"We see this technology as a potential intervention for security applied to our food system," Linton said. "It may be possible to develop this technology so that we can begin decontaminating produce while it's in transit.
"Much of our produce comes from other countries where we may have less control over sanitary practices in the field. If we could use technology like this to seal up produce and treat it as it travels from point A to point B, it's a great application for protection of our nation's food supply."
Also participating in this research were Yingchan Han, post-doctoral research associate; Travis Selby and Krista Schultze, graduate students in the Department of Food Science; and Phil Nelson, professor of food science. The U.S. Department of Agriculture Cooperative State esearch and Extension Service and the Food and Drug Administration provided funding for this work.
Writer: Jennifer Cutraro, (765) 496-2050, jcutraro@purdue.edu
Source: Rich Linton, (765) 494-6481, linton@purdue.edu
Ag Communications: (765) 494-2722; Beth Forbes, forbes@purdue.eduAgriculture News Page
Related Web sites:Purdue University Home Page
WEST LAFAYETTE, Ind. - Open up a pint of strawberries from the grocery store, and more often than not you'll find a fuzzy berry or two in the mix. A blast of chlorine dioxide gas, however, promises to not only keep those berries fuzz-free, but also to kill off harmful bacteria living on their surface more efficiently than methods currently used by the food industry, say Purdue University researchers.
"Strawberries are tricky," said Rich Linton, professor of food science and one of the leaders of the current study on decontaminating strawberries. "They're notoriously difficult to clean, and their surface composition actually encourages bugs to grow."
Those bugs can include potentially lethal bacteria, such as E. coli, as well as viruses including hepatitis A, which caused an outbreak linked to frozen strawberries in 1996.
"The issue with strawberries is that they're easily contaminated," Linton said. "They're grown in close association with soil, where they may pick up pathogens such as E. coil from manure-based fertilizers, and they're hand-picked, providing another avenue for contamination."
Linton and his colleagues at Purdue's Center for Food Safety Engineering, who already have demonstrated the efficacy of using chlorine dioxide gas to kill pathogens on the surface of apples and green peppers, have shown the treatment also removes significantly higher levels of pathogens than the current industry-standard chlorinated water rinse.
Linton's study, published in the current issue of the Journal of Food Protection, compares two different chlorine dioxide treatments, called "batch processing" and "continuous processing." Both treatments provide greater than a 5-log, or 99.999 percent, reduction in the numbers of E. coli and Listeria monocytogenes on strawberry surfaces.
Food safety experts assess decontamination efficiency with a measurement called "log reduction," which indicates how much contamination can be reduced after a decontamination treatment. A log, or logarithm, is a power of ten; thus a 1-log reduction is a 90 percent reduction; a 2-log reduction is a 99 percent reduction, and a 5-log reduction is a 99.999 percent reduction.
While current methods for removing pathogens on strawberries yield about a 2.5 log reduction in bacteria levels, the Food and Drug Administration has stated produce treatments should achieve a 5-log reduction in pathogens.
Not only does Linton's treatment significantly reduce the number of potentially harmful pathogens growing on strawberries, it also extends their shelf life without sacrificing quality attributes such as color and taste.
"The berries last a lot longer after this treatment-in fact, we've had strawberries in the refrigerator for more than six weeks with no mold growth," Linton said.
"If this process can give consumers even one or two more days before the strawberries they buy get fuzzy, that's huge. Think about it - how many strawberries do you have to throw away in a pint? If we could reduce that number, it would be a great advantage for consumers and the industry."
The two methods Linton used differ in the way the berries are exposed to the chlorine dioxide. In a batch system, the strawberries are placed in a sealed container, and a set amount of chlorine dioxide gas is applied once and then allowed to remain in the chamber for a period of time. Continuous treatment involves constant delivery of gas into the chamber over time.
Batch treatment required higher concentrations of chlorine dioxide treatment for longer amounts of time than continuous treatment, but both methods achieved more than a 5-log reduction in pathogens, Linton said.
He found that either 30 minutes of batch treatment, or 10 minutes of continuous treatment, produced effective levels of decontamination.
Linton's team currently has funding through the United States Department of Agriculture to scale up this technology and further develop it for use by the food industry.
"We see this technology as a potential intervention for security applied to our food system," Linton said. "It may be possible to develop this technology so that we can begin decontaminating produce while it's in transit.
"Much of our produce comes from other countries where we may have less control over sanitary practices in the field. If we could use technology like this to seal up produce and treat it as it travels from point A to point B, it's a great application for protection of our nation's food supply."
Also participating in this research were Yingchan Han, post-doctoral research associate; Travis Selby and Krista Schultze, graduate students in the Department of Food Science; and Phil Nelson, professor of food science. The U.S. Department of Agriculture Cooperative State esearch and Extension Service and the Food and Drug Administration provided funding for this work.
Writer: Jennifer Cutraro, (765) 496-2050, jcutraro@purdue.edu
Source: Rich Linton, (765) 494-6481, linton@purdue.edu
Ag Communications: (765) 494-2722; Beth Forbes, forbes@purdue.eduAgriculture News Page
Related Web sites:Purdue University Home Page
Sunday, February 10, 2008
Image gift from Roland
"Mit Gutem Gewissen" Strawberries from Roland. (He posted them for me on Fluxlist Europe: http://fluxlisteurope.blogspot.com)
Subscribe to:
Posts (Atom)
