Domain: Healthcare — Nutrition & Dietetics
Target concept: Comparison of steaming and boiling of broccoli for nutrient retention (color and texture changes...)

Video generation prompt: In the kitchen, simultaneously cook equal portions of broccoli florets: the left pan uses a steaming basket to steam over gently simmering water, while the right pan fully submerges the broccoli in boiling water. After cooking, both are separately removed and placed on plates.

Evaluation guide:
(i) Target concept: Differential thermal processing alters pigment stability and cell wall integrity in cruciferous vegetables.
Minimum mechanism: Water-mediated heat transfer (boiling) must exceed vapor-phase heat transfer (steaming) in both energy delivery rate and solute exchange capacity to drive observable color dulling and texture softening.
(ii)Storyline: Frame opens on static overhead kitchen view showing two identical pans side-by-side. Left pan: visible simmering water surface + elevated steaming basket containing broccoli. Right pan: visible boiling water surface fully covering broccoli. Steam rises continuously from left pan; vigorous bubbles break surface in right pan. After fixed duration (implied by visual readiness), hands enter frame using tongs: first lift steamed broccoli from basket onto left plate, then lift boiled broccoli from water onto right plate. Final frame holds both plated samples in sharp focus, enabling direct side-by-side comparison of color and texture. No camera movement; fixed focal plane; consistent lighting; all actions occur within continuous time flow without cuts or jumps.

Manual:
Experimental Procedure
1. Place equal portions of raw broccoli florets into two identical pans.
2. Left pan: insert steaming basket over gently simmering water; add florets to basket.
3. Right pan: add boiling water to fully submerge florets.
4. Cook both simultaneously until tender-crisp (~3–5 min).
5. Remove florets from both pans and place separately on two plates.
Observation of Experimental Phenomena
- Steamed broccoli: vivid green color, sharp floret edges, no surface water.
- Boiled broccoli: duller (olive/yellow-tinged) green, softened floret edges, faint surface water film.
Summary of Experimental Principles
Steaming preserves heat-sensitive nutrients (e.g., vitamin C, folate) and chlorophyll integrity better than boiling, which causes leaching into water and thermal degradation — resulting in superior color retention and firmer texture.

Prompt Grounding rubric:
level_1: The kitchen setting, the broccoli florets, or the two pans are missing entirely, or only one pan appears instead of two, or neither a steaming basket nor a pot of boiling water is shown, or no plates appear after cooking.
level_2: The kitchen scene appears, but at least two of the following are missing: a steaming basket in the left pan, broccoli fully submerged in the right pan, gently simmering water beneath the left pan's basket, boiling water in the right pan, equal-looking portions of broccoli florets in both pans, or the two cooked portions placed on separate plates afterward.
level_3: Both pans are visible, one to each side; broccoli florets appear in both; a steaming basket sits above water in the left pan; water is visible beneath the left pan's basket and inside the right pan; both cooked portions end up on plates, but at least one element is swapped or wrong (e.g., the steaming basket is in the right pan instead of the left, the broccoli in the left pan is fully submerged rather than steamed, or only one plate is shown at the end).
level_4: Every element from the prompt is present and correctly assigned: the left pan holds a steaming basket over gently simmering water with broccoli florets inside the basket; the right pan holds boiling water fully covering an equal-looking portion of broccoli florets; after cooking, both portions are removed and placed on two separate plates within the same shot, with no swapped containers, no missing pan or basket, no left/right reversal, and no broccoli appearing already cooked before the heat is shown being applied.
level_5: Everything required at the 4-point level holds, and in addition: the steaming basket sits clearly above the water line with no contact between them; the left pan shows small, gentle bubbles rather than a rolling boil, while the right pan shows large bubbles breaking the surface throughout; the broccoli florets keep their distinct shape in both pans right up until removal; and the two final plates are styled the same way and placed symmetrically relative to their pans, leaving no doubt about which plate came from which pan.

Scientific and Causal Correctness rubric:
level_1: The steamed and boiled broccoli look identical at the end (same green intensity, same firmness), with no color or texture cue distinguishing the two cooking methods, or neither sample shows any visible change from its raw state.
level_2: One sample shows a change inconsistent with its cooking method (for instance the steamed broccoli looks waterlogged and dull like the boiled one, or the boiled broccoli looks as crisp and vivid as the steamed one), or both samples end up with the same color and the same firmness, giving no basis for comparison.
level_3: Only one of the two expected differences shows up correctly (either the steamed broccoli looks visibly greener/brighter than the boiled broccoli, which looks duller or more olive-toned, OR the steamed broccoli keeps sharper floret edges while the boiled one looks softer at the edges) but not both together, or one of the two differences points the wrong way (e.g., the boiled sample looks firmer than the steamed one).
level_4: Both expected differences appear together and point the right way: the steamed broccoli is a brighter, more saturated green with crisp floret edges and little to no surface water sheen, while the boiled broccoli is a duller, more olive- or yellow-tinged green with visibly softened, less-defined floret edges, with the dulling and softening confined to the boiled sample and not the steamed one.
level_5: Everything required at the 4-point level holds, and in addition: the steamed broccoli's bright green color and crisp floret edges show no sign of dulling or softening, while the boiled broccoli shows a clear, unambiguous shift toward olive/yellow-green along with visibly softened edges, and any water discoloration or cloudiness in the boiling pan reads as the ordinary, mild leaching expected from submerged boiling (consistent with the manual's own explanation of nutrient and pigment loss) rather than an exaggerated effect like foaming, gushing color, or visible browning/charring.

Spatiotemporal Consistency rubric:
level_1: Broccoli florets jump from one pan to the other between frames, a pan's position or orientation changes abruptly with no visible cause, steam or water appears or disappears from one frame to the next with no transition, the room's lighting swings between two very different states within a single cut, or a plate appears in frame before its broccoli has been removed from the pan.
level_2: At least two moderate breaks occur: the rising steam plume cuts on and off with no cause, the simmering water's surface motion stops and restarts with nothing triggering it, broccoli florets appear to move without any tongs, ladle, or bubble touching them (e.g., floating upward on their own), or a plate enters the frame from off-screen with no visible motion bringing it in.
level_3: Exactly one spatiotemporal flaw is present: for example steam appears only after the broccoli has already been lifted out (an inversion of cause and effect), or the water level changes suddenly with no visible evaporation or boil-off to explain it, or a floret shifts position between frames with no tongs or bubbles touching it, while both pans, the broccoli, and the plates otherwise stay intact and the apparent light source stays in the same place and brightness throughout.
level_4: No pan, broccoli portion, or plate glitches to a new position, disappears without cause, or breaks apart on screen; no lighting or shadow discontinuities occur; steam rises continuously from the left pan while it is cooking; the left pan's water shows a gentle, steady ripple while the right pan shows a clearly more vigorous boil; the broccoli florets stay put in their pans until the tongs actually lift them out; and the two plates, once placed, remain fixed in the frame for the rest of the video.
level_5: Everything required at the 4-point level holds, and in addition: the steam plume rises straight up from the water's surface beneath the steaming basket with no sideways drift and no steam appearing to originate from the broccoli itself; the boiling pan shows bubbles breaking the surface continuously across the whole cooking segment with no pause; the two removal actions (lifting the steamed broccoli, then the boiled broccoli) happen with the same tool and a similar smooth motion, in a clear order; and the shadows cast by both pans and the plates stay consistent with a single overhead light source throughout, with no flicker or geometric warping.