Using microwave as method of sterilization provides several advantages:
Steam sterilization method needs very long time and has bad effects on flavor. A succession of rapid heating and rapid cooling prevents significant flavor changes. Microwave energy provides the rapid heat.
Irradiation destroys the molecular structure and generates harmful irradiation residue. Why use a dangerous method if a safer alternative is available. The microwave energy itself is dangerous as it boils water molecules on path. This danger is easily prevented by a suitable enclosure. More important thing, microwave never leaves residues.
Microwave is very convenient to use. Imagine it as a small piece of gadget house in a box.
Reduced cost. Far more lower cost than steam and irradiation methods. The thing it refers to is the time. More jobs could be done with microwave as compared with two other methods.
The best thing to do is keep them away. If you succeed, any additional measures will all be effective or not needed. However, if some spore forming spoilage bacteria slip thru, there are two ways to deal with them. First is by pressure heating, 121 C for 15 minutes or thru the use of old school tyndallization method.
After reviewing the properties of spore forming bacteria, recalling how heat resistant and resilient it is and knowing that it activates and become vulnerable when condition is favorable. I thought the culprit could be attacked and successfully eliminated by allowing it to activate then heat it while on its most vulnerable state. A dirty war tactic.
If feasible, it might allow sterilization in absense of autoclave and pressure cooker and could be done on heat sensitive items such as plant seeds.
Just as I thought, it is feasible. It is an old and long process known as tyndallization. The food in process is boiled for few minutes, about 15 to 40 minutes depending on food type and volume. The process is repeated after 24 hours and after 72 hours. The food temperature is maintained at 37 C between boiling period. That is to allow spore activation and prevent its formation.
Engr. Tony and Doris Arcangel of Bapamin Enterprises, Batac, Ilocos Norte thru Mag-Agri Tayo shared the products they are producing out of sweet sorghum. They are the following:
Fresh juice. A sweet extract gathered after passing the harvested stalks via mechanical presser. Fresh extract can be drink as is, concentrated or mixed to other juice of different type.
Ethyl alcohol – They are bottling them as sanitizer for personal and hospital use. They are also willing to venture into large scale ethanol production if there will be an investor support on part of planting additional sweet sorghum crops. Ethyl alcohol or ethanol is a by-product of yeast activity. Under anaerobic condition the yeast consume sugar resulting to release of carbon dioxide and alcohol. The initial product is distilled once to several times depending on required concentration and purity.
Sweet Sorghum Syrup – They are claiming it as healthy and comparable to supplementary vitamin. Syrup is made by evaporating some moisture component thru heating. Depending on sugar content, it may be classified as light, medium and heavy.
Vinegar. A resulting product when the ethanol or wine is contaminated with acetic acid bacteria or intentionally added with. The ethyl alcohol produced by yeast activity is converted to acetic acid in presence of oxygen.
They are also selling sweet sorghum grains and seeds and on the track in making flour for gluten-free bread. Sorghum is a no-waste commodity. Bagasse can befermented as high moisture fodder that can be fed to ruminants or used as biofuel feedstock for anaerobic digesters.
Their main products is are marketed under the brand name Healtika. Their product research, development and marketing continues thru the help of Mariano Marcos Statte University (MMSU), Department of Agriculture – Bureau of Agricultural Research (DA-BAR) and Department of Science and Technology (DOST).
What is the boiling point of pure water? This is such an easy question to answer. Even a student at kinder garten will be able to cite the correct answer promptly. That is 100 °C. Easy to remember and easy to pronounce. However, we often forget the argument that comes with it. Boiling point of pure water is 100 °C at sea level. The phenomenon lowers as the altitude rises due to lowering atmospheric pressure.
For a fixed time period, lower boiling point is less effective and thus the more chances of processed food spoilage. Boiling time should be increased for open-kettle boiling and pressure should be increased for pressure canning.
The table below details the water boiling point at different altitudes.
Baguio is 5,000 ft above sea level. Water boiling point is approximately 95 °C.
Tagaytay City is 2,000 feet above sea level. Water boiling point is approximately 98 °C.
Mayon Volcano is 2,463 m (8,081 ft) above sea level. Water boiling is 91.9 °C.
Cordillera is 8,200 feet above sea level. Water boiling point is approximately 91.9 °C.
Mount Apo is 9,692 feet above sea level. Water boiling point is slightly higher than 89.8 °C.
The e-book Complete Guide to Home Canning provides many useful information about boiling and pressuring canning adjustment at different elevation. Here are some excerpts.
Boiling food 10 minutes at altitudes below 1,000 ft destroys Clostridium botulinum bacteria poison when it is present. For altitudes at and above 1,000 ft, add 1 additional minute per 1,000 ft additional elevation. That means the same food should be boiled for 17 minutes in Cordillera Region.
Internal canner temperatures are lower at higher altitudes. To correct this error,
canners must be operated at the increased pressures specified.
Weighted-gauge canners at altitudes above 1,000 feet, must be operated at canner pressures of 10 instead of 5, or 15 instead of 10, PSI.
Here are other snapshots of table containing adjustment examples.
I was wondering why the solar dryer was positioned on far front of the building near the street side. I know the solar dyer needs sun’s energy to perform its function and needs to be on open field. However, it seemed not made of sturdy materials and would break apart against strong wind blows. Taking the equipment indoor should be a good option but there was a group of big black stones at the bottom that would make transfer near to impossible. Maybe the stones was serving as structural support. Unknown period of time passed and what I expected happened. I saw it was broken after a typhoon.
The information I accidentally read on bulletin board answered some of my questions, plus bonus additional knowledge. Read it below.
A solar dryer uses passive solar energy. It converts the sun’s energy into heat without the application of any mechanical device. The structure of the solar dryer serves as the thermal mass that provides the means to collect solar energy and convert it to heat. Thermal mass can be increased by laying stones or small boulders painted black to serve as heat collectors at the base of solar dryer. Air heated by the thermal mass expands thereby increasing its capacity to remove moisture. Furthermore, heated air will rise up and exit through a vent at the top of the structure. This chimney effect ensures a continuous flow of air through the materials being dried.
The solar dryer can be used in a wide range of products such as dried seafoods, seaweeds, banana chips, dried fruits, dried herbs, coffee beans, dried chili, dried flower and etc… almost any kind of agricultural produce.
The plastic enclosing the drier is made of MacPlas Heliofilm which should have an expected service life of 5 years.
Note: I am not sure if the broken solar dryer and the solar dryer on illustration are of the same type.
I replied to her immediately saying sugar palm and coconut have no pectin or not a good source of. What was my basis? I based my quick response on similarities of fruits which are good pectin source. Known pectin rich fruits are citrus, pineapple, mangoes and other acid fruits. Sugar palm meat or kaong is not acidic as far as my reserve knowledge remembered. However, my deduction is not accurate so I am going to check it later and update about the more accurate assessment.
Mr. Google gave me an exactly opposite result. I found a 2008 study entitled “Extraction of Pectin from Sugar Palm Meat”. It was stated that study authors were successful in extracting up to 20% of pectin using ethyl alcohol as solvent.
I got the study freely from the net, from www.cheee.engr.tu.ac.th. I am also hosting it here to help to its wider and faster distribution. Get the article here….
I forgot one important thing about kaong fruit. The sugar palm meat at its harvest maturity is becoming a chewy gel, somewhat similar to nata de coco, when cooked. The gelling phenomenon might be contributed by high pectin content.