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.
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.
Some corns are white, some are yellow and some are orange. Do you wonder why? Which corn color do you prefer? She likes white corn. Orange corn is preferred for making duldol in few towns of Batangas. I prefer the yellow sweet corn.
Color is indication of corn’s beta carotene content. White corn contains almost none, yellow corn has and orange corn has the highest quantity. Our body converts this substance to vitamin A. Again, which corn do you prefer?
In our locality, the orange corn is grown only for animal feeds. Few people are eating those. Notice that all corn for sale are white and yellow (for human consumption). Buy cracked corn from nearest poultry supply and you will get orange corn.
Now that I know orange corn has high amount of beta carotene, I will consider it a choice for my next buy. Do I need to buy it from nearest poultry supply?
Corn is a staple food, next to rice. Its a rich source of carbohydrates. Philippines is a rice eating country but corn is a popular choice in times of calamity and lack of budget.
What is the problem with corn? The problem with corn is the same as the problem with rice, they lack many of the essential nutrients. One of them is the Vitamin A – needed for good eyesight. Some maize contain beta carotene but are way below the requirement.
Agricultural Research Service is on the run to develop corn with beta carotene content. The job is not easy cause corn is a very diverse crop. They need to screen lots of corn to find the potential candidate for development.
The target content is 15 micrograms per one gram. If successful, this will be of great help in fighting world hunger.
My head is achy. Feels like someone is hammering it repeatedly. I cannot do my routine household choir and daily assignments. Then mom told me to take medicine right after eating. Never take a medicine when hungry or stomach upset may occur.
For me the above scenario holds true until my baby boy’s pediatrician says something different. Most of the medicine she prescribes should be taken on full stomach. But this medicine should be taken about one hour before feeding and any food should not be given for approximately one hour. The doctor further explained that milk and other food will hamper its absorption. If I am not mistaken, the medicine is the iron supplement.
Some medicine should be taken on full stomach and some should be taken on empty stomach. This is in accordance with US Food And Drug Administration Statement:
Does it matter if I take a medicine on a full or empty stomach?
Yes, with some medicines. Some medicines can work faster, slower, better, or worse when you take them on a full orempty stomach. On the other hand, some medicines will upset your stomach, andif there is food in your stomach, that canhelp reduce the upset. If you don’t see directions on your medicine labels, askyour doctor or pharmacist if it is best totake your medicines on an empty stomach(one hour before eating, or two hours after eating),with food, or after a meal (fullstomach).
Consult your doctor before deciding when to take your medicine. Empty or full stomach?
Hot-packing is the preferred way of canning foods. The less popular way of canning is the so called raw-packing. Reading the next paragraphs can give you better understanding of the two packing methods.
In raw-packing, freshly prepared food is packed to bottles or can, not cooked. Then the can is filled with a hot syrup or brine. The container is sealed the process in a pressure cooker.
The popular hot-packing method is done by pre-heating fruits before filling into containers, then adding hot syrup or brine. The cap is half-sealed for processing in an open kettle then sealed immediately after. When processing with a pressure cooker, the container is fully sealed before processing. Time and temperature of heat treatment depend on type of fruits or vegetables.
Tin can is suitable only for pressure canner process.
Between the two methods, raw packing has a great disadvantage. Fresh foods contain about 10-30 percent air, it may include oxygen that cause oxidation.
Pre-heating of foods allows the removal of entrapped air in fruits and vegetables. Less oxygen inside the food container means longer shelf life. Air removal will prevent growth of most microorganisms except for anaerobic bacteria and will retain food color and flavors.
When I was in college, I had a different understanding about the two packing methods. I learned the hot-packed and the cold-packed instead. Hot-packed, The food is heated to desired temperature, packed and sealed immediately then cooled in a water bath. Cold-packed, the food is pre-heated, packed in bottles, half-sealed, pasteurized for a given time and temperature, jars are fully sealed and cooled in a water bath.