2020

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The Earth gets its heat from the Sun. From sunrise to sunset, radiation from the Sun falls on the Earth heating the ground. The ground heats the air in contact with it which, in turn, heats the air above that. At the same time, the warm Earth is radiating heat out into space. During the day, the amount of radiation received greatly exceeds that being sent out so things warm up. As the Sun gets lower in the sky in the afternoon, the amount of radiation falling on the ground decreases until, about 3-4pm, the amount of radiation going out equals the amount coming in. That is the time of the maximum temperature. After that, the incoming radiation is less than the outgoing and the temperature falls. After sunset, the incoming radiation ceases but the outgoing continues and the temperature falls further. At sunrise, the incoming radiation starts again and a few minutes after sunrise the incoming and outgoing radiation are equal again. This is the time of the minimum temperature. Things start warming up again after that. The radiation out from the planet is from solid surfaces such as earth, rocks, plants, water droplets in clouds etc. These radiate more or less than each other. Some surfaces lose heat quickly while others do so more slowly. Smooth shiny surfaces lose heat faster than rough surfaces such as bark. As the ground cools overnight, it cools the air immediately in contact with it. This, in turn, cools the air above that and so on. As the ground continues to cool so the air near the ground is colder than the air above it. This is called a temperature inversion.

Water vapour in the air is in a constant state of flux with evaporation and condensation taking place all the time. If the rate of evaporation exceeds the rate of condensation, the air is clear. If the rate of condensation exceeds the rate of evaporation, the excess water is deposited as dew or forms fog or cloud.  The temperature at which the rates of condensation and evaporation are equal is called the dewpoint. At this temperature the air is said to be saturated and there is 100% relative humidity. Above the dewpoint evaporation exceeds condensation. If the temperature falls below the dewpoint, condensation exceeds evaporation. In winter, the dewpoint can be close to or below 0°C. If the temperature falls below the dewpoint at these temperatures, the excess water vapour does not condense to form dew but changes from the gas, water vapour, to the solid phase, ice, without going through the liquid phase. These icy deposits are frost. Frost forms on the coldest surfaces first so smooth car windscreens, which radiate heat better than rough surfaces, get the first frosts. Sometimes there will only be frost on the car, not on the plants but once frost starts to deposit on the grass and the plants,   it usually works from the ground upwards. This is because the coldest air is usually close to the ground. Air temperature as reported by the Bureau of Meteorology is measured in a thermometer screen. The bulbs of the thermometers are 1.5m above the ground. As the coldest air is below the thermometers, the air temperature can be 2-3°C while there are frosts on the ground. The Bureau considers an air temperature of 2.2°C in a thermometer screen to be the frost level minimum temperature. With that temperature in the screen, it is probable that there is frost on the ground. All this takes place on calm, clear nights. If there is wind, it mixes the cold air near the ground with warmer air above it (remember the temperature inversion) raising the temperature. If there is cloud, the cloud absorbs some of the outgoing radiation and re-radiates it in all directions including back to the ground thus raising the temperature. It is unlikely you will get frost on a windy or cloudy night. Even a full moon can provide enough radiation to lift the surface temperatures. We are only looking at frost here. Cold blasts from the Antarctic, cold enough to drop snow on the ranges are another matter altogether but, fortunately, these seldom occur in the subtropics. Sometimes the air is very dry. Temperatures fall as usual but the temperature does not fall below the dewpoint. This means there is no deposition of frost but with temperatures below freezing, plant material will freeze. This is often called a black frost and can be devastating even though no white frost has been seen. How can we minimise the effect of frost?  There are various methods and I will discuss a few of them. Cold air is denser than warm air. If you are on the top or side of a hill, the cold air close to the hillside caused by the ground radiating is denser than the warmer air away from the hillside. The denser air rolls down the hill into the valley being replaced by warmer air.  You can avoid many frosts by planting near the top of a hill rather than in the valleys. Unfortunately a really bad frost will hit the hilltops too so it isn’t 100% reliable. Remember the natural frost preventers, wind and cloud? Wind mixes the cold air with warmer air above raising the temperature. Farmers do the same by lighting fires in the corners of their fields to create convective currents that will mix the air. Asparagus farmers have been known to hire helicopters to fly up and down the fields mixing the air. It works. Large fires and helicopters might work on farms but might annoy the neighbours in a smaller suburban setting. If money is no object, those large space heaters would do a good job. Cloud prevents frost by absorbing and re-radiating the outgoing radiation. Greenhouses do the same thing. Build a greenhouse over your orchard and your frost problems will disappear – but that is impractical. Most fruit trees really only need protection when they are small. Once they are two or three metres high, they are away from the coldest air which is on the ground and they are protected at the lower levels by bark.  For one or two trees it is quite practical to build portable greenhouses out of clear plastic sheeting and conduit pipe. Igloos and tepees are good shapes. Pop the igloo over the young tree when frosts are expected and take it off when the temperature rises in the morning. As the plastic is clear, it would be safe to leave it during the day but these things are light and a good wind will destroy them. Even so, they are inexpensive and it is worth experimenting with them until the plants are big enough to look after themselves. A really bad frost will defeat the greenhouse but it should protect the plants from most frosts. Frost prevention, therefore, falls into two areas. Either mix the cold air at the ground with warmer air above or prevent the radiative cooling. I have suggested some ideas, you might think of others.

Sheryl: I saw some clear plastic pallet covers which would cover your trees against frost $17.50 each.                                                          

Steve retired from the Bureau of Metrology – NSW a few years ago. He also has degrees in Anthropology and Linguistics.

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“Food irradiation exposes certain types of food to a source of ionising energy. Under the standard covering the irradiation of food in Australia, this energy can be in the form of Cobalt 60-sourced gamma rays, machine-generated X-rays, or an electrically generated electron beam”  (www.consumersonline.gov.au/content/food/Irradiated.asp).  Irradiation does not significantly increase the temperature or change the physical or sensory characteristics of most foods. An irradiated apple will still be crisp and juicy. However, irradiation cannot be used with all foods. It causes undesirable flavour changes in dairy products and it causes tissue softening in some fruits, such as peaches and nectarines.

How does it work?

All ionizing radiation is able to remove an electron from an atom or molecule making it highly reactive. The reactive molecules react with other molecules damaging the cell’s molecular machinery and processes. Most cellular machinery can be effectively repaired. However high doses can be sufficient to destroy cells outright. Cells in the process of replication are more severely affected than other cells. The molecular damage:  Inhibits sprouting; Delays ripening and ageing; Kills or sterilises some insects and parasites; Reduces the levels of bacteria and therefore increases shelf life.

Methods
1. Electron beam irradiation
“Electron beam irradiation uses electrons accelerated in an electric field to a velocity close to the speed of light. Electrons do not penetrate the product beyond a few inches, making it necessary to treat fruit and vegetables individually; on the other hand, treatment times are only a few seconds.” (Wikipedia).

2. Gamma radiation
“Gamma radiation is radiation of photons in the gamma part of the spectrum. The radiation is obtained through the use of radioisotopes, generally cobalt 60 or in very few cases cesium 137. It is the most cost-effective technology and is preferred by many processors because the good penetration enables administering treatment to entire industrial pallets or totes, greatly reducing the need for material handling. A pallet or tote is typically exposed for several minutes depending on dose.” (Wikipedia).

3. X-Ray irradiation “Similar to gamma radiation, x-rays are a lower-energy substitute for the former. These systems are scalable and have good penetration, with the added benefit of using an electronic source that stops radiating when switched off. They also permit very good dose uniformity. However these systems require a great deal of electrical energy when operating, and exposure times are longer than with gamma rays.”

“Radioactive materials usually release alpha particles (helium nuclei), beta particles (quickly moving electrons or positrons) or gamma rays. Alpha and beta rays can often be shielded by a piece of paper or a sheet of aluminium, respectively.” “Gamma rays are less ionizing than either alpha or beta rays, but protection against them requires thicker shielding. They produce damage similar to that caused by X-rays such as burns, cancer, and genetic mutations”. (Wikipedia).

The energy waves are not retained in the food just as food cooked in a microwave oven or teeth and bones that have been X-rayed do not retain those energy waves.

Dosage    

Levels of absorbed radiation are currently measured in kiograys (kGy). The scientific community has defined three levels of food irradiation:

• Low dose up to 1kGy – kills insects on fruit and grain and kills or prevents the maturation of Trichinella • Medium dose 1-10 kGy – kills most of the bacteria that cause foodborne illness (1.5-3.0kGy for poultry)

• High dose 10+kGy can sterilize meat and other foods and decontaminate herbs and spices.

Is it new?  
The process was patented for food preservation in 1905 by a French scientist. American research began in 1921 when the U.S. Department of Agriculture (USDA) reported that irradiation would effectively kill trichinae in pork. Since then, it has gradually gathered momentum with improvements in the technology and the need for new methods to combat foodborne illness. http://www.fmi.org/media/bg/irradiation.pdf

Nutrient loss 
Many of the molecules our body requires can be made (nouveau) from the broken molecular bits and pieces absorbed via our digestive tract. However there are some nutrients we can’t make from scratch. Most animals don’t need to eat Vitamin C because they can make it. We have the genes to make it but one does not work due to mutation. We therefore need to consume food containing Vit C to remain healthy. There are many nutrients we cannot make from scratch so it is important that our food contains them.

A joint FAO/IAEA/WHO study concluded that ‘food irradiated to any dose appropriate to achieve the intended technological objective is both safe to consume and nutritionally adequate’. The Australia New Zealand Food Safety Council (ANZFSC) stated that irradiated foods will not have any significant impact on the average dietary intakes of essential vitamins and minerals. Charlotte P. Brennand, PhD, Extension Food Safety Specialist March 1995 FN-250.8 states, “nutritional losses are less than or about the same as cooking and freezing”.
Most sources approximate 5- 10% of Vitamin C is lost due to food irradiation.

Vitamin	Non-irradiated sample	Irradiated sample
Vitamin A (international units)	2200	2450
Vitamin E (milligrams)	3.3	2.15
Thiamin (milligrams)	0.58	0.42
Riboflavin (milligrams)	2.10	2.25
Niacin (milligrams)	58.0	55.5
Vitamin B6 (milligrams)	1.22	1.35
Vitamin B12 (milligrams)	21	28
Pantothenic acid (milligrams)	13	17
Folacin (milligrams)	0.23	0.18

Table 1. Vitamin content comparison of cooked chicken (irradiated and not irradiated). Amounts are for 2.2 pounds (1 kilogram) cooked chicken. Reference: Journal of Food Processing and Preservation 2:229, 1978.

Radioactive food Some people are concerned that irradiated food will be made radioactive. “Radioactivity [is the] disposition of some elements to undergo spontaneous disintegration of their nuclei associated with the emission of ionizing particles and electromagnetic radiation, as alpha particles or Beta particles and gamma radiation” (Henderson’s Dictionary of Biological terms 10th Edition Eleanor Lawrence). According to Charlotte P. Brennand, PhD, Extension Food Safety Specialist “the ionizing radiation used by [food] irradiators is not strong enough to disintegrate the nucleus of even one atom of a food molecule”.   The irradiation process involves passing food through an irradiation field; however, the food itself does not ever contact a radioactive substance.

Don’t be concerned about “interesting human mutations” occurring as a result of eating irradiated food. Food irradiated in the standard way cannot pass on radioactivity let alone radioactivity that will cause DNA damage.

It is physically impossible for food to become radioactive due to the process of food irradiation just as your teeth do not become radioactive after you have had a dental X-ray. Irradiation is radiant energy. It disappears when the energy source is removed.

Genetically damaged food
“Interesting human mutations” will not occur as result of eating genetically damaged food. A genetic mutation cannot be caught like a cold.  Depending on the type of irradiation used, DNA within the food may or may not be damaged. “Gamma or neutron irradiation is often used in conjunction with other techniques, to produce new genetic lines of root and tuber crops, cereals and oil seed crops. New kinds of sorghum, garlic, wheat, bananas, beans and peppers are more resistant to pests and more adaptable to harsh climatic conditions. In Mali, irradiation of sorghum and rice seeds has produced more productive and marketable varieties.” http://www.uic.com.au/peac.htm.

Radiolytic contamination                                                                                                              
Any kind of treatment causes chemical changes in food and that includes irradiation. The substances produced by irradiation are called radio-lytic products just as the chemicals produced by cooking could be called thermo-lytic products.

“Irradiating meat can produce benzene” and “irradiating carbohydrate-rich foods can yield formaldehyde”. Radiolytic products can be found in “cooking, canning and pasteurisation”. “At prescribed dosage levels irradiation produces small amounts of such compounds”. http://www.fmi.org/media/bg/irradiation.pdf
Scientists find the changes in food created by irradiation minor to those created by cooking. See Charlotte P. Brennand, PhD, Extension Food Safety Specialist March 1995 FN-250.8 or look up Cytochrome p450 enzymes (multi-purpose enzymes that often handle thermolytic products and more).

If you are serious about not eating irradiated food because of radiolytic products you should be serious about giving up cooked food.

Some people are concerned that irradiation will result in the formation of stereoisomers. Stereoisomers are molecules that are constructed with the same atoms but the arrangement differs in such a way that the molecules are mirror images (of each other) that cannot be superimposed (just like a left and right hand). A left-hand glove does not fit a right hand. This property is known as chirality. All but one of the 20 naturally occurring amino acids (building blocks of proteins) are chiral and are made naturally in a ‘left-handed’ form. Molecules of natural sugars are almost all made naturally in the ‘right-handed’ form (including the sugar that occurs in DNA). When molecules are manufactured in a biological system usually only one of the stereoforms is made (eg. ribose is usually made right-handed) however whenever these molecules are synthesised artificially, approximately 50% will be one stereoform and 50% will be the other. This can be a problem for the body as it is prepared to handle the naturally occurring form. This is what happened in the Thalidomide fiasco. One of the Thalidomide stereoisomers can be easily cleared by the body the other is not easily cleared. Nowadays regulated pharmaceuticals have the non-biological isomer product removed so that the body can remove the drug.

So if you are worried about irradiation because of stereoisomer formation then you shouldn’t be buying unregulated tablets or capsules of Vitamin E, synthesised amino acids or synthesised sugars unless you know the stereoisomers have been removed.

Old molecules synthesised biologically are known to flip (to the other isomeric form) for no apparent reason.

So if you are concerned about stereoisomers you should think twice about consuming any ‘old’ food eg. herbs that are not freshly picked.

The problems with stereoisomers are well known and regulated in the pharmaceutical industry. Since irradiation is regulated I would hope any problem of stereoisomer formation would have been taken into consideration. “Independent scientific research on the subject [radiolytic products produced by food irradiation] has been extensive, leading to endorsement of food irradiation by the US Food and Drug Administration, the United States Department of Agriculture and the U.N. World Health Organization as a safe, effective process”.  “The effects of food irradiation have been studied for over 60 years.” Wikipedia.

What irradiated foods are currently approved in Australia and New Zealand?   Approval was granted in September 2001 for the use of irradiation on herbs, spices and herbal infusions for control of microbes and for reduction of pests of quarantine concern.  In March 2003 the Food Standards Code was changed to allow the irradiation of the tropical fruits: breadfruit, carambola, custard apple, litchi, longan, mango, mangosteen, papaya and rambutan as a pest disinfestation measure for pests such as the fruit fly. The permission is for irradiation to a maximum of 1 (kGy) from machine-sourced electron beams or x-rays, employing Good Manufacturing/Irradiation Practices. Irradiated tropical fruits require mandatory labelling.

http://www.foodstandards.gov.au/mediareleasespublications/factsheets/fac…

Irradiated Foods Overseas:
More than 50 countries have approved irradiation for about 50 products according to the International Atomic Energy Agency (IAEA), and 33 are irradiating foods and spices commercially.

Chile irradiates about 130 metric tons (mt) per year, mostly spices, according to Nordion. Russia treats 400,000 mt each year, mostly to eliminate insect infestations from imported grain coming into its port of Odessa. China irradiates garlic to prevent sprouting and Japan treats potatoes for the same reason. France irradiates poultry to control contamination. http://www.fmi.org/media/bg/irradiation.pdf.

Conclusion: Fresh is best but I would not say “no” to an irradiated apple.

Sites of interest:

http://www.foodstandards.gov.au/mediareleasespublications/factsheets/fac…
http://www.consumersonline.gov.au/link.asp?URL=http://www.foodstandards….
http://www.dakibudtcha.com.au/Narangbah%20Irradiation%20Plant.htm

Note from Sheryl:   Tirsha has been an active member of our Club for a number of years and is also a member of the Skeptics, The Mycological Society of Queensland, a bookclub and other organisations. Her background is in biochemistry, genetics, aviation, minerals and education. She is currently a ‘Project Scientist’ at CSIRO at Pullenvale.

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At the SE Strawberry Expo at Greenville, NC and the Carolina Farm Stewardship Association Conference at Boone, NC this past November, many growers expressed interest in nutritional plant health products new to this region. I am excited about such unique supplemental plant health products. Some, for soil application, contain enzymes that will cause a great increase in soil’s natural population of bacteria to improve soil structure, water and air permeability and help unlock bound-up currently unavailable soil nutrients. Some, for drip irrigation to roots, improve plants without applying more nitrogen. Some, formulated for foliar application, provide fastest plant response. All are designed to supplement your soil improving fertility program. Several are OMRI certified for organic growers, some now are formulated with food-grade nutrients for sustainable, non-toxic use. With improvements in plant absorption technology, use of food-grade nutrients prevents plant absorption of heavy metals or other impurities that may be contained in non-food grade nutrients, and/or toxins that could become part of the fruits or vegetables that we would consume. Look for this information on the product labels!

For many years, horticulturists and agronomists have largely subscribed to the belief that foliar feeding of plant nutrients is an idea of dubious merit. A commonly held opinion is that foliar nutrients feeding is best employed only where a specific minor element deficiency may exist as determined by tissue test of plant foliage or leaf petioles. Dramatic and fast correction of such nutrient deficiencies are generally always seen from such foliar applications. Dr. H.B. Tukey, renowned plant researcher and Head of Michigan State University’s Department of Horticulture back in the 1950’s, working with research colleague S.H. Wittwer at MSU, first proved conclusively that foliar feeding of plant nutrients really works. Researching possible peaceful uses of atomic energy in agriculture, they used radio-active phosphorous and radio-potassium to spray plants, then measured with a Geiger counter, the absorption, movement and utilization of these and many other nutrients within plants. They found plant nutrients moved at the rate of about one foot per hour to all parts of the plants. Comparing efficiency of plant use of foliar-fed nutrients versus soil-applied nutrients near roots, they found foliar feeding provided about 95 percent efficiency of use compared to about 10 percent of use from soil applications! Likewise, speed of absorption and use by foliar applications was immediate, whereas from soil applications absorption and plant use both were very slow, thus providing a major benefit of foliar feeding where a specific plant nutrient deficiency may exist, be it major or minor plant nutrient.

You’ll note from references of these researchers’ work cited at the end of this article, that this very important finding was published, but only in research journals and symposia proceedings. These findings rarely found their way into the ranks of Extension educators or their grower-focused publications and other teaching materials or programs. I am living proof of that, nor was this information taught in my academic classes way back in the late 1950¹s and early Œ60¹s. Now, a half-century later, I believe it is important to bring these science-based findings to light and publicize this work to benefit growers and their crops. Armed with this knowledge they dug out of the research journals, commercial agricultural chemists began developing foliar feeding formulations.

Their continuous product improvement research has resulted in products containing not only specific plant nutrients, but also natural plant sugars that aid rapid entry and movement into and through plants, plus cytokinins: natural plant growth hormones extracted from seaweed, now stabilized for several years of shelf life. Together with nutrients, they aid natural plant defense mechanisms to resist many plant diseases and insect pests. We know that healthier plants, like humans, are better able to resist many pests compared to those in stressed, poor condition. Also, growers know and observe that the weakest plants are the ones most often attacked by many insect, disease and mite pests. I believe such products can help improve your soil and your plants’ health for higher yields with lower pest control inputs and plant nutrients costs, based on my tests over the past year and ongoing at our farm. Remember, a relatively small amount of plant nutrients, foliar-applied, can replace a much greater amount that is soil-applied, and is immediately available to plants. The development of a low-cost, natural soybean oil-based adjuvant for use with such foliar-applied nutrients and crop protectants further improves leaf and stem coverage and retention for about $2.50/acre per application. An example, combined with foliar (or even to twigs and stems after leaf drop) potassium to benefit berry, grape and tree fruits plants in late fall/early winter, or during winter in milder areas when applied anytime temperatures are above freezing: To toughen/harden plant cells, apply one gallon per acre of foliar-formulated potassium. In two weeks apply a second spray of two gallons of foliar K per acre. Add 1 pint/acre of the soybean oil adjuvant first to the tank, then a small amount of water while agitator is running, then add the potassium product and fill tank with water with agitator running, then spray. 1 gallon of the potassium per acre plus 1 pint of adjuvant oil per acre costs about $18.50 per acre per application for materials, is rain-fast in 15 minutes and is great insurance at very low cost for high-value horticultural crops. Note: Use only 50 mesh screens at the spray tips so the cytokinins will pass through to your plants. With clean spray water, I also can remove my tip screens and can also use larger spray tips to insure no clogging. For smaller areas foliar applications for 4 gallon backpack sprayer, use 1 ounce of the spray oil in 1 quart of water, stir, then add 16 oz. of the foliar potassium, stir, then fill tank with water while stirring. Shake tank from side to side while applying to maintain agitation to prevent settling. Do NOT apply this program through drip irrigation systems, as this product is formulated for foliar use only. Seaweed extracts may clog

some drip irrigation filters. A clear potassium solution is available for drip irrigation and also supplies no plant-tenderizing nitrogen in the fall or winter.
References cited for further reading: 1. Tukey, H.B. and Wittwer, S.H., 1956. The entry of nutrients into plants through stem, leaf and fruit, as indicated by radioactive isotopes. Progress in Nuclear Energy Biological Sciences Scries Six, pp. 106-114. McGraw-Hill. New York and Permagon Press, London.      2. Tukey, H.B., Wittwer, S.H., Teubner, F.G., and Long, W.G., 1956. Utilization of radioactive isotopes in resolving the effectiveness of foliar absorption of plant nutrients. International Conference on the Peaceful Uses of Atomic Energy, Vol. 12: 138-148. United Nations, N.Y.      3. Witter, S.H., Teubner, F.G. and McCall, W.W. 1956. Comparative absorption and utilization by beans and tomatoes of phosphorus applied to the soil and foliage. Proceedings, American Society for Horticultural Science. (needs vol and pp numbers from Barden).

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Here goes….mind you I am not an expert, just an informed amateur.

Green bean can be kept with little trouble or preparation for years. In fact, the green bean, like wine, changes with age and becomes more complex as it ages! This is not the case for roasted beans. Whole roasted beans will deteriorate noticeably within two weeks irrespective of how they are stored. There is much debate over how to store roasted beans: we don’t, so we don’t have a storage problem. Ground roasted beans will start to deteriorate noticeably within a day! In days gone by, every country house would roast their own beans on a daily basis with small hand cranked wood fired roasters. Small urban roasters operated in urban areas to service neighbourhoods. It was only for the second world war that mass produced instant coffee was prepared to keep the troops happy. This led to the decline in the standard of coffee as a drink overall.

There is a whole story in itself on the roasting side of the preparation. First crack, second crack and where to stop the roast. Cinnamon, City or Viennese are the names of these roasts. Then there is blending or not, and the differences in taste between the beans themselves….perhaps not this article. We roast our own with a lovely machine that allows you to see the beans darkening and to hear the cracks of the beans to determine the stage of roast. Lots of fun and you can experiment and blend and vary the roasts and get very technical and really impress your guests as you demonstrate the “art” of roasting. It certainly is a talking point.

Once roasted we tip the beans into our grinder and only grind as we need to. The grinder has a hopper on top and a “dosser” to drop a measured amount into the cup/strainer in the handle of the group head (the heated mass of metal that the handle attaches to). At this stage the important issue is to get a consistent measure of coffee into the cup/strainer so that the rate at which heated water (at 95 degrees C) passes through the group head is perfect. The resistance to the pressure of the water should be such that in less than 30 seconds you get 30ml of expressed coffee. Sounds easy you say…..well it can be once everything is set up, here are some of the things that affect the porosity of the ground coffee: the bean type, roast, grind fineness, moisture content of the ground coffee, amount of ground coffee in the cup/strainer, the pressure at which the coffee is pressed into the cup/strainer, the pressure of the heated water that passes through the handle, the type of strainer etc. The main aim is consistency so you should try to keep as much constant as possible and vary just a few of the variables so that you get a consistent 30ml in 30 seconds. We adjust the fineness of the grind (easily adjusted on a good grinder) and keep everything else constant, that is until we decide I want to try some different roasts. We stopped using a double spout handle because it was so different to the single spout handle (quantity of coffee in the cup/strainer and the resistance of the sieve itself) that we needed two different grind sizes….a pity but we get consistent coffee doing it the way we do.

Finally, the milk should be heated to no more than 60 degrees otherwise it gets scalded and it tastes well …scalded. We use a thermometer, but at a pinch we could use our finger on the metal jug as we heat it up.

Thermometers are cheap and easy to use.

We have invested in a manual coffee espresso machine that is robust, does NOT use a thermo block heating element and has a good steam and separate hot water (95 degrees ) outlet for tea or heating our cups. From our research and experience, fully automatic machines are a good way to show off to your friends that you have no idea about good coffee; manual machines are the way to go.

We love our coffee. We grow it, pick it, pulp it, dry it, hull it, roast it, grind it, express it and finally drink it. It is a journey and like all good journeys it is about the experience, but after all this experience it is nice to relax with a great coffee.

Sheryl: I was recently visiting Peter and Ann and got to taste their home made coffee. There is a difference – a huge difference so give some serious thought to giving the process a go.

Peter makes the best coffee I have ever tasted so I asked him to write something up for us.

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I ran across the Brazilian site and here’s a sample of the content. Impressive “out-of-the-box” growing technique. It is important to stress that vine citrus trees are not really vines. Instead, they have drooping branches unable to support themselves. The plants, therefore, have a willow- or umbrella-type canopy. Their branches do not climb like vines nor have special structures to attach themselves to a support structure. The development of citrus trellises, therefore, are quite different than those for grapevines, for example. Vine citrus trees should be planted at 5 to 7 feet spacing, at about 1.5 feet from the posts towards the interior of the trellis. These posts have to be spaced 10 feet between rows, 5 to 7 feet within post lines, and should be 7 to 8 feet tall. Vine citrus trees should be conducted as a single or double stem until they reach the full height of the trellis. Any lateral branch below this should be removed. These stems should be topped immediately above the trellis and allowed to branch out in all directions. These branches will be supported by beams regularly spaced over the lateral posts. The collection of such willow-type canopies will form the vine citrus trellis. Fruiting occurs along the extremities of the drooping branches and the fruit develop below the foliage with beautiful visual effects. Today,in addition to the vine orange variety, we have tangerine and lemon varieties with drooping branches thanks to breeding done at Citrolima citrus nursery. It is important to stress that vine citrus trees are not really vines. Instead, they have drooping branches unable to support themselves. The plants, therefore, have a willow- or umbrella-type canopy. Their branches do not climb like vines nor have special structures to attach themselves to a support structure. The development of citrus trellises, therefore, are quite different than those for grapevines, for example.Vine citrus trees should be planted at 5 to 7 feet spacing, at about 1.5 feet from the posts towards the interior of the trellis. These posts have to be spaced 10 feet between rows, 5 to 7 feet within post lines, and should be 7 to 8 feet tall. Vine citrus trees should be conducted as a single or double stem until they reach the fulll height of the trellis. Any lateral branch below this should be removed. These stems should be topped immediately above the trellis and allowed to branch out in all directions. These branches will be supported by beams regularly spaced over the lateral posts. The collection of such willow-type canopies will form the vine citrus trellis. Fruiting occurs along the extremities of the drooping branches and the fruit develop below the foliage with beautiful visual effects. Today, in addition to the vine orange variety, we

have tangerine and lemon varieties with drooping branches thanks to breeding done at Citrolima citrus nursery.

‘Natal’ Christmas Trees. ‘Natal’ is a very common sweet orange variety in Brazil and its name means ‘Christmas’. So Natal trees means Christmas trees. Of course we also have Valencia, Hamlin, Navel or any other citrus-type Christmas trees. The fact is that the mini-citrus-trees produced by CITROLIMA have been used in the end-of-the year decorations as tropical Christmas trees. They are grafted on Flying Dragon rootstock, a trifoliate-type citrus originated from China, and cultivated into 4 gallon (15 l) pots using composted Pine bark as growing medium. The mini-trees bear fruit regularly. They are kept under full sun but tolerate extremely well up to 30 days indoors, which makes them well suited for the new Holiday decoration. General care is very simple. The potted plants are light and can be easily moved around, giving a tropical touch to the celebrations, which occur in the summer in the Southern hemisphere. The fruit are under full development in December, have a dark green color and a little over an inch (3 cm) in diameter.

Budwood Thermotherapy  The first plants produced with citrus budwood hot treated against the bacteria of Citrus

Variegated Chlorosis (CVC) in 1994 have reached bearing age. The results are better than expected since tree vigor and productivity seem to be also above normal. This indicates the process may have additional benefits other than simply freeing the stock of bacteria. The treatment herein developed is similar to the hot bath used for rootstock seeds and consists in submitting budwood to temperatures above 125 degrees F (52 degrees C) for at least 10 minutes. Treatment parameters vary with budwood variety, physiological stage, and mass.

Budwood Storage  New methods for cold storage of citrus budwood are maintaining the quality of the propagation

material for up to 6 months. Mature budwood is cut, treated with benomyl fungicide, superficially dried and stored in cotton-cloth bags inside plastic bags. The material is inspected fortnightly, abscised petioles removed and the budsticks superficially dried again. Fungicidal treatment is repeated every 2 months. Temperature oscillates between 4 and 8 degrees centigrade ( 39 and 46 degrees Fahrenheit). Budwood may thus be kept for up to 2 years or more with the objective of preserving genetic material only, since bud take is commercially inadequate after the sixth month.

New Layout for Citrus Greenhouses  Citrolima trials have shown significant advantages for transversal bench-

arrangement in citrus greenhouses when compared with the traditional longitudinal layout: better air circulation, lower temperature, easier tree handling, easier worker circulation, and smaller, more manageable number of trees per bench. The main effect is the reduction in ambient temperature as a result of increased air circulation through the lateral screen walls, which have the entire height free at each bench interval. The resulting reduction in the number of plant containers that can be accommodated in the greenhouse is largely compensated by the derived benefits.

Dark Antechambers  Tests carried out in our nurseries indicate that dark antechambers utilized in the citrus screen

houses are advantageous. Dark chambers are built with black screens instead of clear or white ones. The screen at the door to the greenhouse should also be dark, whereas the antechamber door should be clear. The purpose is to avoid attracting insets into the chambers. Should any insects penetrate the chamber, on the other hand, they are attracted to the

clear exit door, thus facilitating their elimination.

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Distribution
Sunda Shelf (Borneo, Sumatra, Malay Peninsula, Java), Sulawesi, West Papua

Description
Chempedak is a wild and also widely cultivated fruit tree of Malaysia and Indonesia. The tree grows to 20 metres (m) in height, in wet tropical lowland and montane forests to 1200 m a.s.l. (4000 ft.). Although symmetrical and conical in shape in nature, in cultivation it is often irregular. All parts of the tree contain latex. In appearance chempedak fruit is similar to jakfruit (Artocarpus heterophyllus), to which it is closely related, in a sub-group of the breadfruit genus. The green, yellow or orangish brown skin is divided into small hexagons and either smooth or covered with small protrusions. It is cylindrical in shape, 25 to 45 cm long by 10 to 15 cm across, 1-6 kg in weight. Like the jackfruit, it is a syncarp, composed of fleshy arils or segments, 30-45 mm across, colored pale yellow, yellow, orange or green. Each aril surrounds a seed. Texture is firm, somewhat fibrous, sweet and rich. Compared with jackfruit, chempedak is sweeter and has less acidity. It has a strong aroma. Consumers like its light and delicate texture. The seeds, 15-25 mm across, are also edible, and an outstanding resource. Unlike jackfruit seeds, they have a thin, edible seedcoat.

Agronomy
The chempedak tree is rapid growing, and does not require a lot of care except in the early establishment phase, where microclimate control (shade, irrigation and staking) is recommended. When a few metres tall, however, full sun is recommended, since trees overshaded will grow too tall for easy harvest. Gliricidia works well as a companion, being gradually cut out as the chempedak nears maturity. The smaller version fully-grown tree is 9-12 m tall, and bears most of its fruit on the lower branches and trunk. Chempedaks vary in yield, however very heavy crops are common. Selected cultivars can be grafted onto chempedak or jackfruit, but seedling propagation is usual. Trees fruit in 3-5 years from planting out.

Problems
Young trees have thin stems, and may be damaged by wind. The bark is subject to disease attack, and tree surgery may be required in later years. Insects are not usually a problem because the leaves are protected by wiry hairs, and the immature fruit has latex in it. However fallen or hanging fruits are attractive to wildlife, especially Brush turkeys in Queensland, and perhaps similar megapodial birds or omnivorous mammals elsewhere. Since some fruit are borne close to the ground, ungulates may consume them directly.

Harvest
If there is an over-supply, the fruit may be picked early and consumed as a vegetable like jackfruit. For ripe consumption, size of protuberances or smoothness of skin in some cultivars, change of skin colour, and yellowing of the peduncle (fruit stem) are all guides to maturity. The fruit peduncle will easily break at the dehiscing point and the harvest fruits, with their long thin peduncles can be ripened at home or stored for later market sale. Cool room storage will extend life. The season lasts about 6 weeks, but different districts may come into season earlier or later depending on latitude and altitude. Close to the Equator two seasons may occur.

The Future
Chempedak has great promise as a “new” tropical fruit outside its current area of distribution. It has heretofore been eclipsed by its better-known “big brother,” jackfruit. However many of those who know jak will immediately be attracted to chempedak. As a backyard or orchard tree it can provide valuable carbohydrates, protein and vitamins. The fact that it has two separate, different-tasting components makes it even more appealing. As a tree crop it can replace a portion of the starch and protein in one’s diet otherwise requiring annual cropland.

On the agronomic side, N.B.Mendiolo, A.J.H.Corner and Roberto Coronel have all reported on the interchangeability of jack and chempedak characteristics. In Queensland the Malaysian cv “China” (pron. “cheena”) is sold as a hybrid between the two species. Coronel (1983) considers this apparent natural hybridization “a hindrance to rapid propagation of chempedak and popularization of its culture,” and suggests future clonal propagation.

How to Use Chempedak
Apart from raw consumption of the arils and cooking quite immature as a vegetable, there are delicious ways to prepare chempedak.

Chempedak Fritters This is a delicious and complete food. Ingredients: Batter for deep frying; whole arils with seeds still inside; flavourings to taste.

Method: Dip arils in batter and deep fry until seed is cooked–about 10 minutes. Serve plain as snack, at market or roadside stall or with rice and vegetables on the side.

Chempedak Seeds The uses of these are only limited by the consumer’s imagination.

Preparation: Remove from arils. Boil until a fork can break a seed, or a little less if using following recipe.

Fried Chempedak Seeds
Method: Fry boiled seeds in a pan with shallow oil. Don’t remove seed coats. With care, they will come off seeds and become nicely crisped. Time of frying can be varied to taste. Light frying gives a starchier taste. Breaking of seeds with implement and longer frying results in a dish like hash-brown potatoes.

Food Value Approximate Nutritional Composition (Dry weight): Protein Fat Carbohydrate Flesh 3.5-7.0% 0.5-2.0% 80%

Seeds 10-13% 1.0% 80%

Reference: Coronel, R., 1983, Promising Fruits of the Philippines, Laguna: College of Agriculture, University of the Philippines at Los Baños Chandlee, D.K., 1988, Artocarpus, Newsletter of the Rare Fruit Council of Australia, No.53, June

Allen, Betty Molesworth, 1975, Common Malaysian Fruits, Kuala Lumpur: Longman (pp.iii,25)

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Since 1996 I have been successfully growing a fruit rarely encountered in the New World.  Inquiries to Chris Rollins at the Fruit and Spice Park in Homestead, Florida, as well as to other knowledgeable fruit explorers, indicate that the species is quite a rare one in this hemisphere.  Not much is known here about Elaeocarpus serratus, also called Ceylon olive.

This species is indigenous to Sri Lanka, formerly Ceylon.  The tree is quite ornamental; in spring the oldest leaves turn blood red and eventually absciss, but the tree remains evergreen.  Many visitors believe it is an avocado tree when they first see it, but it is not related; it is in fact of the Elaeocarpaceae family and its fruits are almost indistinguishable from large green olives (the commonly known olive, Olea europaea, of the family Oleaceae).

My cutting-grown Ceylon olive tree is now eleven years old.  It is planted in the ground at the southeast drip line of a large water oak.  It receives morning and midday sun only, but has nevertheless been providing huge crops for the past three years.  In early summer it begins to form flower buds on long racemes.  By late summer these become strings of delicate, lacy, white flowers.  My specimen is self-fertile and attracts a myriad of insect pollinators, notably flies, wasps and flower beetles.  Fruit set is close to twenty percent.

Ceylon olives become pigeon-egg sized and here in Florida ripen January through March.  They are green and olive-like, and remain so when ripe. The fruits fall when ready and spoil rapidly if not gathered and used.  The flesh texture is pasty and avocado-like, but tastes slightly sour, which may indicate that it will be a source of vitamin C.  Testing will determine whether this is true.

In Sri Lanka these fruits are used as mustard pickles: unripe fruits are first boiled, then squashed flat.  The whole fruits are combined with diced shallots to make a mixture called country mustard.  These pickles are also known as veralu acharu.  Street vendors boil and press the unripe fruits and then sell them seasoned with salt and chili powder.  Softer and sweeter ripened fruits are eaten with jaggery (palm sugar), which makes a pleasant snack.  I’ve found that ordinary table sugar works just as well.  Some Asian shops sell them pickled in salt, sugar and vinegar as Thai olives.  I’ve made many versions of these, but I don’t get too excited over the taste. In India they are called verali pallam; in Sri Lanka, veralu and in Thailand, ca na.  Cooking the sliced, ripe fruits in tomato sauce-based dishes is a different story; they are quite good this way.  The seed kernel tastes like a brazil nut, but is very difficult to extract.  The local squirrels have learned to eat them.

Culture of the Ceylon olive tree is very easy here in Florida.  From seed or cuttings, it grows into a sturdy tree holding very strong branches.  The plant is very cold hardy, down to 23º F (-5º C), with little damage other than on the branch tips.  This tree is also very drought tolerant—no extra irrigation is needed even in severe dry seasons.

My specimen is also extremely tolerant of wet feet.  After exceptional rainfall that killed adjacent olives, peaches, loquats, avocados and chestnuts, the Ceylon olive kept growing. I find that no fertilizers are required.  Best of all, no pests have been noted, including aphids, leafhoppers, caterpillars, sawflies, beetles, ants, mealy bugs and scale insects.

In central Florida, propagation of Ceylon olive is very successful by cuttings, air layers and seeds, but seeds are very perishable and must be planted quickly.  It grows fairly rapidly, becoming a sturdy, full tree, holding strong branches of hard wood capable of safely supporting an adult.

Paul and Luisa Zmoda are the owners of Flatwoods Fruit Farm and grow many fruits.

e-mail: flatwoodsfarm@aol.com Address:  11009 Riverview Drive, Riverview, FL 33578-4469

Article reprinted with permission.

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The Mayans knew the value of the Canistel back in 800 BC. They would gather the maturing fruit from the dense evergreen trees that shaded their thatch homes and place them in the cooled ashes of the fire. Here they would ripen to a golden yellow and would be used as a nourishing staple for everyday life. Today this ancient fruit continues to prove its worth. It is in the sapote family and is well adapted to south Florida. It will bloom and fruit throughout the year depending on the variety and makes a perfect landscape tree for the home garden. It is easy to grow, wind resistant, and tolerant of sandy or limestone soils. And, oh yes, it will provide bushels of fruit for the kitchen. It is delicious when mixed with milk products, making it perfect for milk shakes, ice creams and natural smoothies. The fruit can be eaten fresh of course, but you must wait for the fruit to fully ripen to a soft texture and peel away the thin yellow skin. Immature fruit have sticky latex that is harmless, but sticky and annoying. Added flavouring such as lime juice and honey may be added to taste. The skin and the flesh of the fruit is bright yellow and stable over time. Neither heating nor freezing will darker the bright yellow of the flesh and its texture makes it perfect for pies, milkshakes puddings and bread. No preservatives are needed; your kaniste pie or ice cream will stay bright yellow for as long as you need. Producing your own fruit in the home garden is easy. Look for grafted trees and not seedlings. Seedling trees will grow well, but they will take many years to fruit and will be of unknown and most likely inferior quality. Here are a few varieties recommended for planting:

Bruce is a large, uniform and attractive fruit shaped much like a Hersey’s chocolate kiss (only yellow). Fruiting occurs in two major waves during August to October and again from February to March. There are 2 to 3 seeds in each fruit and plenty to eat.

Fairchild is a compact tree with slightly curved more elongated fruit. The production is heavy and its timing is roughly the same as with the previous variety

Ross is distinctive among the others selections. The fruit are flattened like a hole-less doughnut and often is slightly fluted. The flesh is juicy and there are from 3 to 5 seeds in the fruit. The tree is slow growing and easy to control.

Canistel trees should be planted in the full sun and will require watering until they get established if there are inconsistent rains. Once established they are drought tolerant, partially losing their leaves with the onset of extreme drought. They respond well to mulching. Mulching improves water-holding capacity, nutrient retention and availability, and soil structure. The Canistel is adapted well to life in the Caribbean and can be grown in close proximity to the water. They are not salt tolerant, however and will die with salt water inundation or persistent salt spray. Young trees are cold-sensitive, and should be protected from frost or freezes.  

Fertilization is best done with three applications per year (spring, summer and autumn) of an 8-3-9 or other fruit tree formulation.  

Annual pruning of trees at a manageable height will provide ready access to the fruit.

Harvest: The fruit of canistel do not mature at the same time. They are yellow to orange when they are mature and it is the time to be picked. The fruit can be stored at room temperature for 3 to 10 days for ripening. As they soften, the skin texture changes from glossy to dull. The ripe fruit or the pulp can be preserved and stored by freezing it for up to 6 months.

Propagating  Those ultra dwarf Canistel trees were achieved using inverted root graft. Ref: R. Campbell

Sheryl   There is an excellent specimen in the Brisbane Botanic Gardens.

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John Wrench is a pharmacist, bush food & indigenous species consultant, lecturer and propagator and conducts workshops and guided walks by arrangement. He is also a poet, author and wildlife photographer. Ph: 07 3256 3310

Other Beverages

It is interesting to soak heads of nectar-rich blossoms in water in order to produce a sweet drink. The results are often  disappointing, the liquid proving to have too little sugar and too many insects and bits of plant debris. Some quite delectable fruit drinks, however, can be made by boiling with sugar some of the well-known jam species, and several others not widely known as useful fruits. Most of the syzygium species (Lillypilly group) can be used for jams, desserts and fruit drinks, especially the most famous, the riberry (Syzygium luehmannii) which produces a brilliant red-coloured drink, with a sharp taste and aromatic flavour.

A quite new preparation, introduced by the author, is based on the ripe fruits of the Cooloon (Elaeocarpus grandis) and other species of Elaeocarpus. The shallow layer of greenish flesh under the bright blue skin, and investing the large rugose seed, contains sugar, acid, some interesting tannins, and some intriguing flavour principles. If the fruits are boiled whole with sugar, a pale green syrup is produced, recalling granny smith apples and clove. If the fruits are stripped of flesh (by fingers or grater, etc.) and the whole mixture is boiled with sugar, the resulting syrup is coloured reddish-brown, and the flavour recalls cooked guava as well. Syrup (both kinds) plus cold water or soda water etc, produces a wonderfully refreshing sharp-tasting drink.

Rainforest Fruit Drink

A delightfully refreshing, aromatic drink can be made by boiling a mixture of rainforest fruits with sugar and water at the rate of about one kg. of fruit and 500g. of sugar to four litres of water. Challenge – find more than eight (8) species to use. It is important to include a good proportion of riberry for colour, flavour and acidity, but as many colourful, palatable fruits as possible will enhance the process. Try to include some Diploglottis sp. Store the drink in a large plastic bottle (or several) with the fruit remaining.

As the resultant drink is not preservatised and does not contain the 87.5% sugar of a syrup product to preserve by osmotic pressure, it must be stored in a refrigerator and used within a week or so. On the other hand, freezing smaller bottles of the decanted solution will guarantee a protracted enjoyment of this delight.

The rainforest drink has been served to the public on numerous occasions since 1997, producing a very favourable (near ecstatic) response each time. (Children included!).

Whether or not the fruits are in season, you will be able to try this drink, made from frozen stock held in the freezer for this kind of need. N.B. Save the solids for use in other ways. Freeze for long storage.

Notes on Diploglottis spp.

As the result of fairly widespread cultivation, it is possible to use the fruits of several species of Diploglottis, the so-called ‘native tamarinds: (The true Asian tamarinds are not related, belonging to a different family of plants).

Genus Diploglottis      Family Sapindaceae    (The great rainforest family)

The following species are grown commercially or in public and private gardens in southeast Queensland: 

D. campbelli, D. cunninghamii, D.dyphyllostegia, D. smithii.

D. campbellii is rare and endangered in the wild, but quite widely cultivated. A good specimen may be observed in the BCC City Botanic Gardens near the kiosk. The fruits of Diploglottis are roundish capsules, some up to seven (7) cm. across containing two or three large seeds invested with a fleshy aril or coating. This flesh is orange to red in colour, acidulous (+++) and juicy, making it an ideal component of fruit drinks, jams, desserts. etc.

All references in other articles to the uses of rainforest fruit may be amended to include Diploglottis sp.