Calculator
Example Data Table
| Food | Thickness | Bath Temp | Starting | Estimated Time | Finish Idea |
|---|---|---|---|---|---|
| Beef Steak | 30 mm | 55 °C | Refrigerated | ~1 hr 45 min | Quick sear, then slice |
| Poultry Breast | 35 mm | 63 °C | Refrigerated | ~2 hr 30 min | Pat dry, sear skin-side |
| Root Vegetables | 25 mm | 85 °C | Room Temp | ~1 hr 30 min | Glaze with butter and herbs |
| Fish Fillet | 20 mm | 52 °C | Refrigerated | ~45 min | Light torch, lemon finish |
Formula Used
The calculator uses a heat-up estimator where time grows with the square of thickness: time ∝ thickness². This mirrors diffusion-style heating toward the center of the item.
- time_hours = k_food × thickness_mm² × shape_multiplier × start_multiplier × temp_adjust
- k_food is an empirical factor for different foods.
- shape_multiplier increases time for cylinders and spheres.
- start_multiplier adds time for chilled or frozen starts.
- Optional safety hold and tenderizing minutes are added to the total.
How to Use This Calculator
- Select a food type that matches your ingredient.
- Measure the shortest thickness to the center.
- Pick a preset texture, or enter a custom bath temperature.
- Choose starting temperature: room, refrigerated, or frozen.
- Add a safety hold and tenderizing time if desired.
- Press Calculate Time to see results above the form.
- Download CSV or PDF to share or store your plan.
What the Time Estimate Represents
This calculator estimates how long it takes for the center of a sealed item to approach the bath temperature. It combines thickness-squared heating behavior with food and shape factors, then adds optional holding time you choose. Pair estimates with consistent bagging, circulation, and careful temperature control for repeatable outcomes. Use it to build a prep timeline, not as a replacement for safe handling practices.
Thickness Measurement for Garden Produce
For vegetables from the garden, thickness is the shortest distance from the surface to the center. Slice carrots, beets, squash, or potatoes into uniform pieces so every bag finishes together. If you vacuum-seal a thick wedge beside thin slices, the thinner pieces will over-soften first. When in doubt, measure the thickest piece in the bag and base timing on that value.
Temperature Selection and Texture Targets
Temperature controls texture more than time. Higher temperatures soften plant cell walls and speed starch changes, while lower temperatures preserve firmness in delicate fish and keep meat rosy. Start with a preset, then adjust the bath temperature in small steps to match your preferred bite. Once the center has warmed through, extra time mainly affects tenderness and moisture migration.
Cold-Start and Frozen Adjustments
Starting temperature changes the warm-up curve. Refrigerated items need a modest increase, while frozen foods require additional time to pass through the thawing phase before heating normally. If cooking frozen produce, seal flat for faster thaw and avoid stacking bags during the first half hour.
Using Results for Prep, Packaging, and Finishing
Treat the output as your schedule: warm-up estimate plus any optional holds. Prep seasonings, herbs, and finishing pans while the bath runs. Keep bags submerged and spaced so water circulates. Label bags with the target temperature, start time, and a planned finish method for easy batching. After cooking, dry surfaces thoroughly; quick searing, glazing, or torching adds flavor without overcooking the center. For garden vegetables, a butter-herb glaze or quick char boosts aroma and color.
FAQs
1) Is this calculator accurate for every ingredient?
No. It is a planning estimator based on thickness, shape, and starting temperature. Use it to schedule cooking, then refine with your own results and trusted safety guidance.
2) What thickness should I enter for irregular shapes?
Use the shortest distance to the center of the thickest portion. If pieces vary, base the input on the thickest piece in the bag so everything finishes safely and evenly.
3) Why does time increase so much with thickness?
Heating to the center behaves like diffusion, so time scales roughly with thickness squared. Doubling thickness can require about four times the warm-up time, especially for cold starts.
4) Should I always enable the safety hold option?
Use it when you want extra margin, are cooking thicker items, or need a buffer for busy prep. It adds minutes based on thickness, but it does not replace proper handling and chilling steps.
5) How do I use this for garden vegetables?
Choose a vegetable category, set your thickness from the thickest piece, then pick a higher temperature for softer textures. Bag items in a single layer so water circulation stays strong.
6) What is the best way to finish after the bath?
Dry the surface well, then apply fast, high-heat finishing like searing, glazing, or torching. Keep finishing short so the center stays at your target temperature and texture.