Trays made of high-gas-barrier materials such as proypropylene bonded to an theylene vinyl alcohol polymer.
a plastic container lined with aluminum sealed with adhesives on top
Iron cans lined with tin to prevent oxidation. Most are also lined with enamel to prevent acids from etching through the tin
An inert material that can break easily. Can be hermetically sealed.
Light passes through
Important in field operations.
Must get the highest quality produce to the processing facility in order to produce the highest quality finished product
Holding prior to processing
Inspection and sorting
Slicing, dicing, or sizing
Botanically classified as those plant parts that house seeds. Fruits are mature plant ovaries.
Usually considered to be sweet (fructose or levulose) and thus used in desserts.
Several different classes of fruits: citrus fruits, melons, berries, pommes (pit fruits)
California is a producer of 30-50% fruit.
Glucose + Oxygen ----> energy + CO2 + water
Fruits with high SA have many cells that are respiring giving off moisture. They turn limp and keep relative humidity up.
We want to stop respiration to preserve.
Often picked prior to maturity to ripen in transit, storage, or shelf.
Ethylene gas is used to accelerate ripening. Bananas and tomatoes are high.
Climacteric- Ripen fast
Non-climacteric- low rate of respiration
Fruit that goes past its optimum ripeness.
Senescence can be controlled, to some extent, by lowering the holding temperature and/or by increasing the amount of atmospheric CO2 to a controlled level.
Include the edible part of plants: Leaves, shoots, tubers and piths, roots, flowers, stems.
Largest proportion of vegetables are consumed in the fresh or unpreserved state.
Time is of the essence when preserving quality: microbial spoilage, loss of water, loss of sugar, enzymatic degradation issues.
Vegetables give off up to 100,000 BTU per ton/day bc of respiration.
Added to maintain the water phase within the oil phase.
The product produced is solid at room temp, has less sat fat than butter, and still melts in your mouth (body temp).
A chemical compound that contains both a hydrophilic (binds to the water) and a hydrophobic (binds to the lipid) portion.
Two immiscible liquids that are combined and bound together (stabilized) by another substance. The other substance is the emulsifier.
Emulsifiers may be lipids or mono and diglycerides.
Mono and Diglycerides are made by heating fats or oils and glycerine, in the presence of sodium hydroxide, under vacuum, at about 400 F.Compounds formed can be distilled and purified.
Fats and Oils
Classified as lipids
Unsaturated oils, such as vegetable oils, are subject to oxidation leading to rancidity.
Oils may be converted to a solid at room temperature, and stabilized against oxidation, through the process of hydrogenation.
Solid fats are of animal origin while liquid oils are of plant origin. there are some exceptions
Oils have more mono and polyunsaturated fatty acids than do fats which are saturated to a greater degree.
ester of glycerol and fatty acids (triglycerides).
The fatty acids have varying degrees of saturation and are mostly long, straight hydrocarbons chains. Natural fats may contain 4-24 carbon atoms, generally in even numbers.
Lipids are generally insoluble in water while soluble in organic solvents.
Lipids act as vehicles for the fat soluble vitamins deak
A process in which a solution of oil is heated under reduced pressure and then hydrogen gas is pumped into it in the presence of a catalyst (nickel). The metallic nickel is then removed by filtration through bleaching clay.
Hydrogenation is widely used today and can be regulated to allow for an exact amount of hydrogenation (saturation) to occur.
If a fat/oil is left as it is after hydrogenation is it called shortening (100% lipid).
If a fat/oil is left as it is after hydrogenation, it is called shortening (100% lipid). However, to make margarine, you must add water.
Butter is a water-in-oil emulsion and margarine tries to mimic this. The two products are produced in similar ways.
For margarine, the hydrogenated fat/oil (80%) is whipped vigorously with water (16%) to a homogeneity and an emulsifier is added to stabilize the suspension. Vitamin A and D are added sometimes.
Enriched Nutrients added bad to flour, thiamin, riboflavin, niacin, iron, calcium (maybe), and Vitamin D (maybe).
Brominated bromate added to high protein gluten flours to weaken structure and give unique characteristics. High protein--> less 'toughness'
Whole Wheat flour all particles of flour (bran included) excluding germs are used. Most bakers will blend white flour with wheat flour giving less loaf volume. (50/50 blend)
Self Rising sodium carbonate, calcium phosphate, and salt added to give self-rising properties to flour
Phosphated flours monosodium phosphate plus sodium bicarbonate (NaHCO3) added to flour to give characteristic like self-rising
Semolina very high protein flour used to make pasta. Made from duram wheat
Hard- high protein (12.5-15.5 %) gives 'tougher' crust and texture. Used for white pan bread, hard rolls, yeast sweet goods, high gluten breads.
Soft- lower protein (7.5-10%) gives softer crumb and a less structured texture. Used for angel food cakes, layer cakes, crackers, pie crust.
All purpose flour combine the functions of both soft and hard wheat (9-12%)
Types of wheat for production
Hard red spring wheat-high protein
Hard red winter wheat
Soft red winter wheat- lowest protein
White winter/spring wheat
Duram- highest protein
The most important cereal in milling
Whole wheat averages about 13% protein. whte 11%
Moisture content of bulk stored wheat should not be higher than 14.5% and that of sack stored wheat not higher than 16%
Wheat flour enriched with Fe, Ca, salts, thiamin, niacin, riboflavin
Wheat protein-gluten- gives good baking quality mainly due to elasticity
Gluten is a hydrated form of wheat protein and is comprised of two main components:
Glutenin and Gliadin.
Flour and Cereal Products
Consumption of both flour and grains increased in recent years. In 1987, per capita increased from 139 lbs to 169 in 1972.
Wheat flour represents 75% of the US grain consumed
Wheat is grown in the largest quantity for human consumption in the US
Cereal Grains and Oilseeds
Cereal grains are the seeds of cultivated grasses.