Lecture Notes: Preparing French Fries from Potatoes

Introduction

• Overview of the process: Making French fries from a bag of potatoes
• Goal: Compare the cost of homemade fries vs. buying from McDonald's
• Equipment used: Hefty scales to weigh potatoes

Weighing the Potatoes

• Initial weight of potatoes: 38 kg 200 g
• Weight after peeling: 29 kg
  • Weight loss from peeling: 9 kg
  • Notable insight: Potato peels can add significant weight

Peeling and Cleaning Process

• Peeling method: Use a vegetable peeler and teamwork for efficiency
• Cleaning process:
  • Transfer potatoes to sink for washing
  • Use a sponge to remove dirt effectively
• Final clean weight: 29 kg

Slicing the Potatoes

• Manual slicing: Using a knife to cut potatoes into slices and sticks
• Special potato slicing machine:
  • Features: Metal construction, multiple attachments (country-style, large, medium, small fries)
  • Demonstration: Cutting in one movement, efficient and reliable
• Preventing oxidation: Soak cut potatoes in water

Preparing Sweet and Sour Sauce

• Ingredients for sauce:
  • Peach jam, apricot jam, corn syrup, mustard, vinegar, lemon juice, garlic, water with starch
• Preparation steps:
  • Mix all ingredients and simmer for a few minutes
  • Remove garlic after flavoring sauce
  • Store in a sauce bottle

Frying the Potatoes

• Initial soaking: Removing excess starch
• Frying process:
  • First fry: 15 liters of oil at 140 degrees for 3 minutes
  • Final fry: At 170 degrees for another 3 minutes to achieve a crispy crust
• Importance of frying stages: Ensures proper cooking and crust formation
• Serving: Drain on paper towels and salt

Final Output

• Total fries produced: 7572 pieces
• Total weight of fries: 17 kg 800 g
  • Less than half of the original potato weight

Cost Comparison

• Cost of homemade fries: $37
• Cost of equivalent fries from McDonald's: $286
  • Homemade fries are 7 times cheaper

Conclusion and Distribution

• Packaging: Use special boxes to hold fries
• Distribution: Delivered fries and soda to children in need
• Reaction: Children enjoyed the meal and were happy with the experience.