Exam 2 NS 2310

What are the functions of fats in foods? Make sure you know not just the definition but how they perform that function. Ex: Fat has a shortening function. How does this work in baked goods? Solubility plasticity etc.

A medium that transfers heat to foods without burning them. Forms a layer of steam around foods, locking in moisture, forms crust, cooked inside because of penetration. Tenderizes baked products, highly saturated fats have more shortening power.

Organic acids

Acids cause most fruits to have pH value <5. Lemons, limes, cranberries have lowest <2

Pectin

Act as cell cement between cell wall. Partially responsible for firmness and structure. Made of 3 types (Pectin, protopectin, and pectic acid.)

Pectic substances

Act as cell cement between cell walls. Found in three types, pectin is produced at height of ripeness.

Proper cooking technique for creating stock (i.e. boil simmer etc.)

simmered

Plant pigments - major groups and specific pigments

Carotenoids, chlorophyll, flavonoids.

Vegetable

Any plant whose parts are used for food. In practice the definition is: the edible portion of the plant, raw or cooked

Legume preparation

Best by simmering rather than boiling. 3 soak methods (overnight soak 10hrs before, short soak bring to full boil for 2 minutes and soak in water 1 hour, no soak takes twice as much water and double the heat time will lose skins more easily)

Stock ingredients

Bones of beef, poultry, seafood

Bouillon

Broth made from meat and vegetables and then strained to remove any solid ingredient

Bouquet garni

Bundle of herbs tied together with string used to flavor soups or broths

Fruit and vegetable pigment names and their colors

Carotenoids: carotene, lycopene, xanthophyll found in carrots, oranges, peaches. Chlorophyll: chlorophyll a+b found in broccoli, green cabbage, lettuce. Flavonoids: anthocyanin (red purple) found in eggplant, raddish, red cabbage. anthoxanthin (cream white) cauliflower, onions, turnips. Betalains (purple red) beets.

Parenchyma cell

Cells that store starch, color, water, and flavor, store plastids (leucoplasts, chloroplasts, chromoplasts) Provides turgor pressure

Tofu

Cheese made from soy milk, bland flavor, varies in consistency and firmness, can be used in many dishes

Clear and cream soups

Clear soups use egg whites, cream soups are made from milk or egg yolks.

Gelatin protein content

Collagen is a protein from bones, hides, and connective tissues.

Vegetable selection and storage

Consider the season of year. Grading is based on ripeness, color, shape, size, uniformity, freedom bruises & signs of decay. Refrigerate in crisper, if not available use plastic bag with holes. Wrap vegetables in damp paper towels. Optimum humidity is 85-95%. Blanch before freezing.

Suggestions for lowering daily dietary fat intake

Eat more plant based oils/fats. Dont eat saturated fats.

Where do we find abundant amounts of fats and oils?

Fats come from animal products and most oils come from plants.

White stock

Flavored liquid obtained by simmering the bones of beef, veal, chicken, or pork in water

Phenolic compounds

Found in apples, apricots, avocados... Responsible for browning and bruising. Tannins are phenolic compounds found in unripe fruit. Give a bitter taste and astringent feel.

Moisture content classifications of cheeses

Fresh country cheese >80% water. Soft 50-70%. Semi hard 40-50%. Hard 30-40%. Very Hard 30%.

Flavoring of meat stocks

From meat poultry seafood and/or their bones or vegetables are simmered and strained.

Drupes

Fruit with seeds encased in a pit (apricots, cherries, peaches, plums)

Pomes

Fruit with seeds in a central core (apples, pears)

Fruits mistaken for vegetables and vice versa

Fruits mistaken as vegetables: tomatoes, squash, cucumbers. Vegetables mistaken as fruits: rhubarb.

Grading of milk

Graded according to bacterial count, Grade A- lowest Grade B. Voluntary process.

Pasteurization

Heating milk to 145-212º to kill 100% of pathogenic bacteria and 95-99% of non pathogenic.

Fruits

The ripened ovaries and adjacent parts of a plant's flowers. Type of fruit is determined by the type of flower. (simple, aggregate, multiple)

Meat analog

Imitation meats: soybeans (a type of legume) think tofu, miso, natty, sufu, tempeh, tamari

Steps involved in fruit juice processing

Juice extraction (mechanically or by hand) Clarification (varying amounts of pulp are eliminated) Deaeration (air removed to reduce undesirable changes from oxygen improves shelf life and reduces breakdown of vitamin C. Pasteurization (high heat) Concentration/addition

% fruit juice of beverages

Juice: not less than 100%. Juice drink: Not less than 50%. Nectar: Not less than 30-40%. Ade: Not less

The two most important rules to follow when preparing foods with cheese and why

Keep temperatures low, and heating times short. High heat and prolonged cooking toughens cheese proteins and causes fats to separate out, creating an oily, stringy, and inferior product.

Causes of coagulation and precipitation of milk proteins

Milk proteins coagulate or form a solid under heat, acid, enzymes, polyphenolic compounds, salts.

Basic common steps to cheese production

Milk selection, coagulation, curd treatment, curing, ripening. 10lbs milk yields 1 lb cheese and 9lbs of whey

Stages of cooking that occur in deep-fat frying

Moisture transfer (water on surface vaporizes into surrounding) Fat transfer (a layer of steam forms around the food, protecting it from the high temps of frying and keeps it from being saturated from oil) Crust formation (Becomes larger and more porous from water being driven out of the food by frying heat) Interior cooking (Inner core cooks thru heat penetration)

Emulsifier functions and types

Mono&diglycerides are most common. Phospholipids - lecithin from egg yolks. Milk protein, soy protein, gelatin, gluten, vegetable gums. Polysorbate 60 & propylene glycol monoesters

Refrigeration recommendations for milk

Must refrigerate all fluid milk except unopened UHT milk, certain canned milk products. Lasts <3wks yogurt best within 1st 10 days buttermilk best within 3-4 days up to 3-4 weeks. Sour cream best whiny few days or unopened up to 1 month

Freezing recommendations for cheeses

Not recommended for soft, high-moisture cheese. Best for hard natural cheese with low water content.

Salad dressings

Oil and vinegar dressings. Some made out of dairy products.

Water-in-oil and oil-in-water emulsion and examples of each

Oil in water:fewer oil droplets throughout more water (salad dressings, gravies, mayonnaise) Water in Oil: smaller amount of water dispersed throughout oil (butter and margarine)

Shortenings

Plant oils that have been hydrogenated to make solid and pliable. Soybean oil is the major source. Hydrogenated until solid, then whipped or pumped with air to improve plasticity, turn white.

How to avoid curdling of cream soups

Prepare a fat/flour mixture with either milk or stock. Do not allow soup to come to a boil after adding any dairy product, particularly cheese. Add acid to milk rather than milk to acid.

Turgor

Pressure stored in the cells of plants that provides crunchiness to vegetables and leafy vegetables

Homogenization

Prevents separation of water and fat, mechanical or chemical agents.

Consommé

Richly flavored soup stock that has been clarified and made transparent by the use of egg whites

Storage recommendations for soups/stocks

Should never be refrigerated while hot. Place the soup in a sink of cold water until it becomes lukewarm, then refrigerate.

Fat sources of margarine

Soybean, corn, safflower, canola, partially hydrogenated oils

Types of fat replacers (substitutes mimetics etc.)

Substitutes physically resemble fats, are lipid based, replace fat on a weight to weight basis, duplicate functional properties of fat. Fat mimetics are water soluble, protein or carb based, imitate the mouthfeel of fats.

Changes vegetables undergo when heated

Texture: high heat can gelatinize starch, decrease bulk by softening cellulose and loss of turgor. Flavor: degorge=>peel and slice veggies, sprinkle with salt. Odor: pungent odors=>can be reduced by shortening the heating time, adding vinegar to the cooking water. Color and nutrient retention.

Stock

The foundational thin liquid of many soups produced when meat, poultry and seafood and/or their bones, or vegetables are reduced (simmered) and strained

How to thicken cream soups

Thickened with cream, pureed vegetables, other thickeners like bread, noodles, rice, cornstarch.

Salad layers and ingredients

Under liner: serves as foundation (lettuce or greens). Body: main part of salad. Dressing: adds flavor and moistness (usually tart).

Unrefined vs refined oils

Unrefined have a strong aroma & flavor, low smoking point, high nutrient content, prone to rancidity. Refined have neutral to no aroma, bland flavor, high smoke point

How to prepare a quality leafy green salad

Use finest quality ingredients, more assertively flavored foods should be minimal, flavor variety is important, strive for good balance of color, texture, and shape.

Nutrient and caloric content of fruits and vegetables

Vegetables: low in calories, cholesterol, sodium and fat. High in carbs including fiber, vitamins and minerals. Fruits: carbohydrates, vitamins and fiber, minerals, phytochemicals.

Additives found in milk

Vitamin-D, Vitamin A, rBGH (recombinant bovine growth hormone)

Nutrient content of milk

Water 87.4%, 6.6 pH, Carbohydrates (lactose 12g per 8oz) Protein (complete protein source, 8g per cup, casein and whey) Vitamin A, D, Riboflavin (b2), tryptophan, minerals

Sprouting grains

Wheat, corn, barley, sorghum

How to slow enzymatic browning

With denaturing enzymes, adding acids, lowering temperatures, coating fruits, adding antioxidants