什么是非变种番茄？（Heirloom）

什么是非变种番茄？这个名字来自它奇怪的形状和非同一般的功效。非变种番茄对人体健康益处良多，例如，减少精神压力，强健骨骼。千万不要被非变种番茄的奇形怪状和各种颜色吓到，这正是它丰富的遗传多样性带来的过人之处之一。简言之，它们就应该是拥有各种线条轮廓，各式鼓包和各种颜色。只要表皮没有裂痕，它就能吃。非变种番茄的种子就好比家传的瓷器，一直是被当做家传宝物来对待的。只有那些存在至少繁殖了50年的番茄，才被认为是真正的祖传番茄。而那些拥有新的变异基因的番茄则被归为杂交番茄。

成熟时期采摘的非变种番茄，含有更高的维他命。彩虹般的色彩显示着它广泛的抗氧化性，能够帮助我们的细胞抵御过快地老化。优质的非变种番茄可以算作水果的一种，因为它不但多汁，而且味道就像樱桃或葡萄那样香甜美味。

大部分在超市出售的杂交番茄与非变种番茄构成了鲜明的对比。杂交番茄还在青绿色，果实未成熟的时候就被采摘，只为了让它们能够经过长途跋涉也不易腐烂。等到达目的地的时候，再由人工喷洒二氧化碳将其催熟成红色表皮。这些杂交番茄的肉质比较厚实，不容易擦破裂开，但这些所谓的“改善”也必然会有相应的代价。由于这些杂交番茄没有经过自然的成熟期，因此口味缺失很多，营养更是不足。 

选择非变种番茄的五大理由

1. 非变种番茄富含维他命C，有助于滋养人体肾上腺，帮助减缓压力。一个大小适中的非变种番茄含有的营养成分占人体免疫系统每日所需营养的40%。

2. 番茄有益于心血管系统的健康。众所周知，它所含有的钾，叶酸等能够帮助降低血压，并减少心脏病病发率。

3.天然有机的非变种番茄所富含的番茄红素，是胡萝卜素的一种，它能够有效预防癌症。科学研究表明，番茄红素能够帮助预防膀胱癌、乳腺癌、宫颈癌、结肠癌、子宫内膜癌、肺癌、胰腺癌、前列腺癌和皮肤癌等等。

4. 非变种番茄所含有的维他命K能够帮助强健骨骼。俄勒冈州立大学的Linus Pauling研究所指出，及早并坚持服用维他命K，能够有效预防骨质疏松症。

5. 非变种番茄能够使您的菜肴独具一番风味，还不用担心会摄入过多的热量。跟苹果一样，一杯番茄仅含27卡路里，您完全可以把自然成熟的番茄当做美味的零食享用。您也可以将番茄切碎撒入汤中，添加更多的颜色和味道。

提示：透析病人必须减少钾的摄入，每天食用非变种番茄也需要限量。 番茄中所含的生物碱——会引发易过敏者的炎症。

Cooking oil

Types of oils

Natural fats contain varying ratios of three types of fats: saturated, monounsaturated and polyunsaturated.

Saturated fats are hard at room temperature. They're stable, resist oxidation, and are found primarily in meat and dairy but also in palm and coconut oil.

Polyunsaturated fats are liquid at room temperature and the least stable. They oxidize easily and are found in seafood and corn, safflower, soybean and sunflower oils.

Monounsaturated fats are more stable generally than polyunsaturates. They're found in canola, nut and olive oils.

PRESSED VS. CHEMICALLY EXTRACTED

The oils at PCC may be less familiar than brands in mass-market grocery stores — for good reason. PCC buyers seek out natural oils that are mechanically pressed from the seed without using chemical solvents.

Olive, avocado and walnut oils, for example, are from soft fruit or nuts that need only expeller pressing and centrifuging; they may be labeled "cold-pressed."

Hard oilseeds such as soy or canola usually require some pre-treatment such as steam before pressing but still do not rely on chemical solvents.

In contrast, mass-market oils generally are extracted with toxic solvents such as hexane. These oils then undergo harsh treatment to remove the solvent. More chemicals, very high heat, and straining are used to deodorize and bleach the oils — rendering them inferior in taste, fragrance, appearance and especially nutritional quality.

UNREFINED OILS

Unrefined oils are filtered only lightly to remove large particles. Some, such as sesame or olive oil, may appear cloudy or have visible sediment after sitting. This does not compromise quality.

Unrefined oils are "whole" oils and their flavor, color and fragrance are more pronounced than in refined oils. Like unrefined whole grain flours, unrefined oils are more nutritious and have a shorter storage life than refined.

Unrefined oils are best used unheated in dressings or with low heat, sautéing or baking. Their natural resins and other beneficial particles burn easily and develop unpleasant flavors and unhealthful properties if overheated. If you choose to bake with unrefined oils, expect the flavor to be more pronounced.

REFINED OILS

Naturally refined oils are more thoroughly filtered and strained than unrefined, usually with some additional heat, but without harsh or damaging chemicals. Refining reduces the nutrient level and flavor. It also removes particles and resins and makes naturally refined oils more stable for longer storage, more resistant to smoking, and a good choice for high-heat cooking and frying.

Refined oils recommended for high-heat cooking and deep-frying are "high oleic" safflower, sunflower, and peanut oil. These are from plants bred to be high in monounsaturated fats instead of polyunsaturates, which oxidize easily and aren't suited for high heat. To check if it's "high oleic," read the nutrition panel on the bottle. It lists polyunsaturated and monounsaturated fats separately.

Oil	Raw	Low heat	Med. heat	Med. High heat	Very high heat	Characteristics and uses
Low heat = 275 º to 325 º F • Medium heat = 325 º to 350 º F • Medium-high heat = 350 º to 400 º F • Very high heat = 400 º to 495 º F - Please note, oil availability May Vary by store.
Almond, refined	X	X	X	X	X	Pure, clean flavor and a high-heat wonder. Smoke point 495º F.
Avocado (expeller-pressed), refined	X	X	X	X	X	Lovely texture, wonderful for searing meat, whipped potatoes and stir-fries. Smoke point 450º F.
Avocado (cold-pressed), unrefined	X	X	X	X	X	Lovely texture, wonderful for searing meat, whipped potatoes and stir-fries. Smoke point 500º F.
Canola (medium-high heat), refined	X	X	X	X		Neutral flavor, all-purpose, good for baking. Smoke point 425º F. May be genetically modified if not organic.
Canola, unrefined	X	X				Mild flavor, may be genetically modified if not organic.
Coconut (virgin/extra virgin), unrefined		X	X			Lovely for cakes, pie crusts, light sautéing. Cholesterol-free. Smoke point 280º to 350º F.
Ghee		X	X	X		Wonderful in sauces, with lobster or crab, and for quick frying.
Grapeseed (expeller-pressed), refined	X	X	X	X	X	Clean, neutral taste. Smoke point 485º F.
Hazelnut, unrefined	X					Rich flavor. Drizzle on food or use for dipping bread. Potential allergen.
Macadamia nut (cold-pressed), unrefined	X					Nutty, buttery flavor and higher in monounsaturates than olive oil.
Olive (extra virgin), unrefined	X	X				Ideal for salads, raw foods, pesto and dipping bread. Smoke point 325º F.
Olive (extra light/originale), refined	X	X	X	X		Mild and tolerant of low heat. Smoke point 460º F.
Peanut (expeller-pressed, vitamin E added), refined	X	X	X	X		Adds flavor to lightly cooked foods and cold dishes. Smoke point 212º to 400º F. Potential allergen.
Peanut (high oleic), refined	X	X	X	X	X	Neutral flavor for tempura, fish and stir-fries. Smoke point 450º F. Potential allergen.
Safflower (high heat), refined	X	X	X	X	X	Mild flavor for high-heat cooking. Smoke point 450º F.
Safflower, unrefined	X					Delicate flavor.
Sesame, refined	X	X	X	X	X	Adds smoky flavor to seared meats, stir-fries. Smoke point 445º F.
Sesame, unrefined (including toasted)	X					Aromatic, nutty, best in dressings and sauces.
Sunflower (high oleic), refined	X	X	X	X	X	Nearly neutral flavor. Smoke point 450º F.
Sunflower (expeller-pressed), refined	X	X	X	X	X	Multi-purpose. Smoke point 460º F.
Sunflower (cold-pressed), unrefined	X					Rich flavor, best in cold dishes.
Vegetable shortening (palm fruit), refined		X	X	X		Good for cakes, pie crusts, sautés. Not hydrogenated.
Walnut, refined	X	X	X	X		Adds character to salads, marinades and sautés. Smoke point 400º F. Potential allergen.