Sunday, May 15, 2011

Aceites y grasas comestibles

There are three methods for extracting vegetable oils from plants. The relevant part of the plant may be placed under pressure to "extract" the oil, giving an expressed oil. Oils may also be extracted from plants by dissolving parts of plants in water or another solvent. The solution may be separated from the plant material and concentrated, giving an extracted or leached oil. The mixture may also be separated by distilling the oil away from the plant material. Oils extracted by this latter method are called essential oils. Essential oils often have different properties and uses than pressed or leached vegetable oils. Macerated oils are made by infusing parts of plants in a base oil a process known as maceration.
Although most plants contain some oil, only the oil from certain major oil crops [1] complemented by a few dozen minor oil crops[2] is widely used and traded. These oils are one of several types of plant oils.
Vegetable oils can be classified in several ways, for example:
  • By source: most, but not all vegetable oils are extracted from the fruits or seeds of plants, and the oils may be classified by grouping oils from similar plants, such as "nut oils".
  • By use: oils from plants are used in cooking, for fuel, for cosmetics, for medical purposes, and for other industrial purposes.
The vegetable oils are grouped below in common classes of use.

Contents

[hide]

[edit] Edible oils

[edit] Major oils

Sunflowers, the seeds of which are the source of Sunflower oil.
These oils account for a significant fraction of worldwide edible oil production. All are also used as fuel oils.

[edit] Nut oils

Hazelnuts from the Common Hazel, used to make Hazelnut oil.
Nut oils are generally used in cooking, for their flavor. Most are quite costly, because of the difficulty of extracting the oil.

[edit] Oils from melon and gourd seeds

Watermelon seed oil, extracted from the seeds of Citrullus vulgaris, is used in cooking in West Africa.
Members of the cucurbitaceae include gourds, melons, pumpkins, and squashes. Seeds from these plants are noted for their oil content, but little information is available on methods of extracting the oil. In most cases, the plants are grown as food, with dietary use of the oils as a byproduct of using the seeds as food.[24]

[edit] Food supplements

A number of oils are used as food supplements, for their nutrient content or medical effect.

[edit] Other edible oils

Carob seed pods, used to make carob pod oil.
Coriander seeds are the source of an edible pressed oil, Coriander seed oil.

Saturday, November 27, 2010

Scoville heat units (SHU)

The Scoville scale is a measurement of the spicy heat (or piquance) of achili pepper.
The number of Scoville heat units (SHU)[1] indicates the amount of capsaicin present. Capsaicin is a chemical compoundthat stimulateschemoreceptor nerve endings in the skin, especially the mucous membranes.
The scale is named after its creator, American chemist Wilbur Scoville. His method, devised in 1912,[2] is known as the Scoville Organoleptic Test. An alternative method for quantitative analysis uses high-performance liquid chromatography, making it possible to directly measure capsaicinoid content.
Contents

Scoville organoleptic test

In Scoville's method, an alcohol extract of the capsaicin oil from a measured amount of dried pepper is added incrementally to a solution of sugar in water until the "heat" is just detectable by a panel of (usually five) tasters; the degree of dilution gives its measure on the Scoville scale. Thus a sweet pepper or a bell pepper, containing no capsaicin at all, has a Scoville rating of zero, meaning no heat detectable. The hottest chilis, such as habaneros and nagas, have a rating of 200,000 or more, indicating that their extract must be diluted over 200,000 times before the capsaicin presence is undetectable. The greatest weakness of the Scoville Organoleptic Test is its imprecision, because it relies on human subjectivity. Tasters taste only one sample per session.
Naga Jolokia (bhut jolokia, naga morich) is rated at over one million Scoville units. It is primarily found in Bangladesh and the Northeast Indian states of Assam, Nagalandand Manipur
The Red Savina pepper, one of the hottest chilis, is rated at 580,000 Scoville units.
Hottest chilis
The chilis with the highest rating on the Scoville scale exceed one million Scoville units and include specimens of naga jolokia or bhut jolokia and its cultivars, the "Dorset naga" and the "Ghost chili," neither of which has official cultivar status.[4][5] Numerical results for any specimen vary depending on its cultivation conditions and the uncertainty of the laboratory methods used to assess the capsaicinoid content.

List of Scoville ratings

Pungency values for any pepper are variable, due to expected variation within a species—easily by a factor of 10 or more—depending on seed lineage, climate (humidity is a big factor for the Bhut Jolokia; the Dorset Naga and the original Naga have quite different ratings), and even soil (this is especially true of habaneros). The inaccuracies described in the measurement methods above also contribute to the imprecision of these values. When interpreting Scoville ratings, this should be kept in mind.[3]
The Scoville scale may be extrapolated to express the pungency of substances that are even hotter than pure capsaicin. One such substance isresiniferatoxin, an alkaloid present in the sap of some species of euphorbiaplants (spurges), with a Scoville scale rating of 16 billion.[6]
Scoville heat unitsExamples
15,000,000–16,000,000Pure capsaicin[7]
8,600,000–9,100,000Various capsaicinoids (e.g.,
homocapsaicin,homodihydrocapsaicin, nordihydrocapsaicin)
5,000,000–5,300,000Law Enforcement Grade pepper spray,[8] FN 303 irritant ammunition
855,000–1,075,000Naga Jolokia (ghost chili)[9][10]
350,000–580,000Red Savina habanero[11][12]
100,000–350,000Guntur Chilli, Habanero chili,[13]
Scotch Bonnet Pepper,[13] Datil pepper, Rocoto,
African Birdseye (Piri Piri),
Madame Jeanette,
Jamaican Hot Pepper[14]
50,000–100,000Bird's eye chili/Thai Pepper/Indian Pepper,[15]Malagueta Pepper,[15] Chiltepin Pepper, Pequin Pepper[15]
30,000–50,000Cayenne Pepper, Ají pepper,[13] Tabasco pepper, Cumari pepper (Capsicum Chinese)
10,000–23,000Serrano Pepper, Peter Pepper
2,500–8,000Jalapeño Pepper, Guajillo pepper,
New Mexican varieties of Anaheim pepper,[16] Paprika (Hungarian wax pepper), Tabasco Sauce
500–2,500Anaheim pepper, Poblano Pepper, Rocotillo Pepper, Peppadew
100–500Pimento, Peperoncini
0No significant heat, Bell pepper, Cubanelle, Aji dulce

Monday, November 1, 2010

Dátiles

Source
About Dates

Since 4000 years B.C. dates were already appreciated and commercially cultivated in what is known to day as southern Iraq. Today, the main date-producing Arab countries are Algeria, Bahrain, Egypt, Iraq, Libya, Morocco, Oman, Saudi Arabia, Sudan, Syria, Tunisia, the UAE, and Yemen. Between them Algeria, Egypt, Libya, Morocco and Saudi Arabia produce 600 different kinds of dates, which accounts for 60% of the world's production.
Date is basically a fruit of the date palm and looks dark reddish brown, oval, and about 1 1/2 inches long. The date skin is wrinkled and coated with a sticky, waxy film.
Variety of dates
Dates were among the very first fruits cultivated on earth. A product of dry subtropical climatic conditions, the date was initially native to Middle East countries only but today it is planted in areas like North Africa, Iraq, and the Coachella valley in California near Palm Springs. The ‘Bahri’, 'Dayri’ and ‘Khadrawy’ of Iraq and Saudi Arabia, 'Medjool' of Morocco and 'Saidy' of Libya are some of the most famous varieties of dates.
Perny dates, Mabroom dates, Sofry dates, Khudry dates, Suqaey dates, Safawy dates, Shalaby dates, Sukkary dates, Anbarah dates, Ajwah dates, Helwah dates, Madjool dates, Rothana dates, Maktoomi dates, Naboot Seif dates, Rabiah dates, Baydh dates, Rashodiah dates, Sukhal Red & Yellow dates, Sari dates, Umel Kubar dates, Lubanah dates.