Maintenance of textural integrity in frozen, shredded vegetables Li Ni, PhD Danny Lin, M.S. Diane Barrett, PhD Food Science & Technology University of California, Davis
Maintenance of textural integrity in frozen, shredded vegetables Li Ni, PhD Danny Lin, M.S. Diane Barrett, PhD Food Science & Technology University of California, Davis
Outline ◼ Background ◼ Texture measurement of vegetables ◼ Optimization of LTLT pretreatment ◼ Optimization of exogenous CaCl2 concentration ◼ Color improvement of green vegetables
Outline ◼ Background ◼ Texture measurement of vegetables ◼ Optimization of LTLT pretreatment ◼ Optimization of exogenous CaCl2 concentration ◼ Color improvement of green vegetables
Textural integrity of frozen vegetables ◼ Structure and condition of the raw vegetable ◼ Maturity at harvest ◼ Blanching, freezing, thawing and cooking conditions used for preparation ◼ Interaction of the structural components at cell walls and cell membranes
Textural integrity of frozen vegetables ◼ Structure and condition of the raw vegetable ◼ Maturity at harvest ◼ Blanching, freezing, thawing and cooking conditions used for preparation ◼ Interaction of the structural components at cell walls and cell membranes
Cell walls of vegetable tissues ◼ 3-dimensional network of cellulose, hemicellulose, pectin, lignin and proteins ◼ Cemented together by middle lamella ◼ consists of calcium salts of galacturonic acid polymers that have been partially esterified with methyl alcohol cell wall cell membrane middle lamella
Cell walls of vegetable tissues ◼ 3-dimensional network of cellulose, hemicellulose, pectin, lignin and proteins ◼ Cemented together by middle lamella ◼ consists of calcium salts of galacturonic acid polymers that have been partially esterified with methyl alcohol cell wall cell membrane middle lamella
Softening of vegetables by thermal processing ◼ Resistance to deforming forces ◼ Turgor ◼ Cell wall rigidity ◼ Breakage of cell walls accompanied by release of vacuolar contents ◼ Separation of one cell from another - failure at the adhesive layer between the cells
Softening of vegetables by thermal processing ◼ Resistance to deforming forces ◼ Turgor ◼ Cell wall rigidity ◼ Breakage of cell walls accompanied by release of vacuolar contents ◼ Separation of one cell from another - failure at the adhesive layer between the cells