BAKERY PRODUCTS

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BAKERY PRODUCTS
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Bread

• 1. Staling
• 2. Moisture loss
• 3. Mold growth

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Staling

• increase in crumb firmness
• reduction in crispness
• aroma loss

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Mechanisms

• retrogradation of starch
• amylopectin recrystallization
• interaction between gluten and starch
• partial drying
• glassy transition
• moisture redistribution

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• Amylopectin partially crystalline
• after gelatinization
• retrogradation
• amylopectin recrystallization (slow)
• Amylose and branch points of amylopectin present
  in amorphous region

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• Storage temperature
• highest rate of retrogradation 5C
• Moisture content
• Formulation
• type of starch, lipids, surfactants, sugar,
  enzymes, pentosans
• gluten-rich crumbs stale slow

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Piazza and Masi (1995)

• moisture movement from crumb to crust
• dehydration rate staling
• additives delay dehydration
• delay staling

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Baik and Chinachoti (2000)

• Crumb with crust
• aw0.954-0.961 first 3 days
• aw0.936 at day 14
• moisture loss
• moisture redistribution
• not only amylopectin recrystallization
• Crumb without crust
• no change in aw
• at constant moisture amylopectin
  recrystallization

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Hallberg and Chinachoti (2002)

• compared white bread with meal-ready-to-eat bread
• moisture permeable and hermetic package
• SWB after 3 mo became very firm
• MRE 3-15 mo soft, after 4-7 y very firm
• moisture loss
• glycerol
• changes in non-crystalline regions
• more amylopectin crystallization in MRE bread but
  longer time

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Cakes

• 1. Staling
• 2. Moisture loss
• 3. Mold growth
• ERH - Mold-free Shelf Life