Dried fruits food safety
Food safety for dehydrated fruit and veggies
Preserving food when plentiful, to prepare for leaner times, is an ancient practice. There’s evidence cultures in the Middle East and China were using the sun and wind to preserve food such as fish, meat, fruit and vegetables, as far back as 12,000 years ago.
Widely use by combat troops during World War II, dehydrated food, unsurprisingly, fell out of favor with the public after the war. It wasn’t until the cultural revolution of the 1960’s, with a renewed focus on all things natural, that dehydrating foods experienced a renaissance of sorts.
As with all food preservation methods, there are certain steps along the way that present safety issues. Sourcing, producing and storing dehydrated fruits, vegetables and other produce correctly is important. It keeps the food, and the humans who consume it, safe.
Sourcing quality produce
Dehydrated food is cool again. You only need to check the fruit, veggie and health food aisles. People are living busy lives and want portable, tasty and healthy snacks. And not just snacks. Meals resembling grazing tables are almost the norm in some homes and offices around the world.
With the seemingly endless array of food and diet fads, if people can’t make their own food, they want to know what goes into the foods they do buy.
So, it goes without saying, that means sourcing quality produce.
Locally grown fruits and veggies
There’s never been a better time to support local business and buy locally grown, seasonal produce as often as possible. Farmer’s Markets are a great place to start. Buying in season means you’re:
- more likely to buy local produce
- maximising the nutrient content, and;
- getting better value for your dollar.
Not sure what’s in season? Check out the Seasonal Food Guide1 to see what’s in season in your part of Australia.
Australia also has many native flora, including native fruits with ‘unique qualities and potential uses as functional ingredients.’2
Some common commercially produced native fruits:
- bush tomato
- Davidson’s plum
- desert lime
- finger lime
- Kakadu plum
- lemon aspen
- Tasmanian pepper berry, and;
- Illawarra plum.
Our island home
To protect our island home, there’s strict regulations around the importation of fresh produce for commercial purposes. As importing fresh produce for personal use isn’t permitted, Australia only imports for commercial purposes. As the Department of Agriculture, Water and the Environment3 outlines:
‘Fresh produce is unprocessed or partially processed fresh fruit and vegetables. Partial processing may include slicing or removing peel.
Imported fresh produce can introduce exotic plant pests and diseases that could be harmful to Australia’s environment, agriculture and economy. To safeguard Australia, we set conditions for the import of all fresh produce to Australia.’
Australia’s food laws
Foods imported for human consumption must comply with the Imported Food Control Act 1992,4 as well as Australian state and territory food laws. Overseen by the The Department of Agriculture, Water and the Environment,3 imported foods must also meet the standards of the Australia New Zealand Food Standards Code.5 The code is developed and maintained by Food Standards Australia New Zealand (FSANZ).
Storing and transporting fruits and vegetables
Australian Cold Chain Guidelines6 help maintain the safety and quality of food products as they’re handled, transported and stored.
‘The Cold Chain consists of a series of businesses engaged in manufacturing, transporting, storing, retailing and serving fresh, chilled and frozen foods.
Over the last two decades, the distance that foods travel from paddock to plate has increased. The average food is moved in and out of refrigeration control 14 times before consumption.’
That leaves a lot of room for contamination as the produce moves from producer to consumer.
The Cold Chain conditions are set out in three rules:
- Never warmer than rule, which is about temperature
- Maximum ‘Out of Refrigeration rule, which is about time
- First expiry, first out rule, which is about stock rotation.
While the manufacturer can set any never warmer than and keep above temperatures, cold chain guidelines strongly recommend:
- Chilled foods must be transported, stored and handled at temperatures never warmer than +5°C; and
- Frozen foods must be transported, stored and handled at temperatures never warmer than -18°C.
Those in the cold chain should also regularly review policies and operating procedures as part of Hazard Analysis Critical Control Points (HACCP) and internal Food Safety Programs.
What the HACCP
Originally developed by NASA and a group of food safety specialists in the ‘60s, Hazard Analysis Critical Control Point (HACCP) is an internationally recognised food safety and risk assessment plan. The plan outlines seven key principles in food safety:
- Hazard Analysis
- Critical Control Points
- Critical Limits
- Critical Control Monitoring
- Corrective Action
- Record Keeping.
While not mandatory, Australian providers to the food industry can have their products endorsed as food safe under HACCP Australia7 guidelines.
Some fruits, such as apples, bananas, nectarines, pears, peaches and apricots will benefit from some pre-treatment before drying. Pre-treating with an acidic solution like citric acid or ascorbic acid will:
- Reduce oxidation
- Helps destroy harmful bacteria
- Gives a better colour
- Helps reduce vitamin loss, and;
- Lengthens shelf life.
Other methods of pre-treating are:
- Sugaring - soaking fruits in a sugar syrup for up to 18 hours
- Sulphuring - sulphur is ignited and burned in an enclosed box with the fruit
- Sulphite dips - sodium bisulphite, sodium sulphite or sodium meta-bisulphite are dissolved in water and used as a fruit soak
- Fruit juice dip - a juice high in vitamin C, such as lemon or pineapple juice, can be used instead of an ascorbic acid mix
- Steam blanching - fruit and vegetables are steamed over boiling water. However, this can change the flavour and texture
- Water blanching - place vegetables in water than has been brought to a rolling boil. Times vary based on the vegetable.
The drying process removes moisture from the food. This also hinders the growth of mould, bacteria and yeast and ensures the dehydrated fruit and vegetables don’t easily spoil.
A major contributor to drying food is humidity. As drying involves removing the moisture from the food and releasing it into the surrounding air, low humidity helps the drying process. This is why the drying of foods originated in the warmer and drier countries around the planet. Higher humidity will slow down the drying process as the air would also be heavy with moisture. Increasing air flow can speed up the drying process.