Domain: Healthcare — Nutrition & Dietetics
Target concept: Food Processing (Fermented Flour)

Video generation prompt: Two bowls containing equal amounts of flour were placed on the table. The flour in the left bowl was mixed with an appropriate amount of yeast powder and warm water, then kneaded evenly. The flour in the right bowl was mixed with water and kneaded evenly. Both bowls were then placed in a 30°C environment to ferment for 2 hours. The scene was focused on the two bowls of dough, and continuous photography was conducted for several hours.

Evaluation guide:
(i) Target concept: Biological leavening via yeast-mediated anaerobic fermentation in wheat dough.
Minimum mechanism: Yeast cells must be viable and active at 30°C; gluten matrix must be sufficiently developed to entrap CO₂; absence of yeast must preclude gas production; water-only dough must remain physically stable without enzymatic or microbial activity.
(ii)Storyline: [Frame 0–2] Two empty bowls placed side-by-side → [Frame 2–3] Equal flour poured into each → [Frame 3–4] Yeast + warm water added to left, water only to right → [Frame 4–5] Sequential kneading: left then right, with hands contacting only one bowl at a time → [Frame 5–6] Both bowls moved together into shared thermal environment (visual cue: uniform ambient glow or labeled chamber) → [Frame 6–10] Fixed-view time-lapse: left dough gradually domes and reveals subsurface bubbles; right dough retains flat, dense profile with zero porosity emergence. Perspective: static, eye-level or slight overhead, no occlusion, full bowls always in frame.

Manual:
Experimental Procedure
1. Place two identical bowls side-by-side on table; fill each with equal amount of white flour.
2. In left bowl: add yeast powder + warm water, then knead until uniform dough forms.
3. In right bowl: add water (no yeast), then knead until uniform dough forms.
4. Place both bowls in same 30°C environment.
5. Maintain fixed overhead/side view capturing both bowls continuously.
Observation of Experimental Phenomena
After fermentation: left bowl dough swells visibly, develops porous, bubbly surface; right bowl dough remains compact, dense, smooth, and non-porous.
Summary of Experimental Principles
Yeast metabolizes sugars in flour, producing CO₂ gas trapped in gluten network → causes leavening (swelling & porosity). Without yeast, hydration alone yields inert dough with no gas production → no swelling or pore formation.

Prompt Grounding rubric:
level_1: Two bowls are not shown at all, or only one bowl appears; the bowls contain no flour or dough; yeast powder is never shown being added to either bowl; no kneading action is shown for either bowl; the two bowls are stacked, placed far apart, or otherwise not positioned near each other for direct comparison; the video gives no indication that the bowls are later kept in a warm setting.
level_2: Two bowls of flour appear near each other, but the left bowl never receives yeast powder, or warm water is added only to the right bowl instead of the left, or only one of the two bowls is ever kneaded, or the two bowls are not shown being placed into the same warm setting together, or the camera view cuts, pans, or zooms before the fermentation period begins, breaking continuous observation.
level_3: Two bowls sit next to each other on the table, each holding a similar amount of flour; the left bowl's flour is mixed with yeast powder and warm water, then kneaded into dough; the right bowl's flour is mixed with water only (no yeast) and kneaded into dough; both bowls are then shown together in the same warm setting; the camera holds one consistent view; every step named in the prompt (flour, yeast/water addition, kneading, joint placement in the warm environment) appears in the correct order.
level_4: Everything at the 3-point level holds, AND the left bowl (yeast dough) and right bowl (water-only dough) keep the same left/right arrangement for the whole video, so which bowl is which is never ambiguous from position alone; the kneading of each bowl is shown as a distinct action, with hands working one bowl's dough at a time rather than both together; no object other than the intended ingredients and hands ever blocks either bowl from view; the video moves directly from kneading into the fermentation time-lapse with no unexplained gap.
level_5: Everything at the 4-point level holds, AND both bowls stay fully visible and evenly lit for the entire video, with neither bowl darker, brighter, or more obstructed than the other; no hand or utensil enters the frame except during the kneading actions already described; once both bowls are placed in the warm setting, the cue for that setting (e.g., a consistent ambient glow or an enclosed proofing space) stays present continuously rather than appearing only briefly.

Scientific and Causal Correctness rubric:
level_1: Neither bowl shows any visible change in size or surface texture by the end; or both doughs rise and turn bubbly to the same degree; or the water-only (right) dough is the one that swells and bubbles while the yeast (left) dough stays flat; or both doughs develop identical surface cracking with no visible difference in porosity between them.
level_2: A difference appears, but not the correct one: the left (yeast) dough shows no rise while the right (water-only) dough visibly swells; or bubbles are visible only in the right bowl; or the left dough only cracks on top without any real doming or bubble formation while the right stays smooth; or the surfaces of both doughs darken to the same extent, obscuring any real difference between them.
level_3: The left (yeast) dough visibly rises and its surface becomes bubbly and porous; the right (water-only) dough stays compact, dense, and smooth with no bubbles; neither dough changes color; the rise and bubbling in the left bowl is clearly greater than anything seen in the right bowl; this difference persists and is still visible in the final frames of the video.
level_4: Everything at the 3-point level is true, AND the bubbles and porosity in the left dough are unevenly distributed across its surface rather than forming a uniform grid; the right dough's surface stays smooth and pore-free everywhere, not just in isolated spots; the left dough does not visibly collapse or sink back down after rising; neither dough shows pooling liquid or a wet sheen inconsistent with normal fermentation.
level_5: Everything at the 4-point level is true, AND the left dough's rise appears as a gentle, rounded doming rather than a sharply torn or split surface; any bubbles visible in the left dough stay beneath or just at the surface rather than bursting into visible foam that spills over the bowl's rim; the right dough keeps essentially its original flat or lightly settled shape with no pores forming anywhere on it; neither dough develops a dry crust or surface discoloration by the end of the video.

Spatiotemporal Consistency rubric:
level_1: One of the bowls suddenly shifts to a new position on the table (a jump of more than about a quarter of the bowl's own width) with no visible movement connecting the two spots; a bowl is absent from the frame for a stretch and then reappears; the whole scene abruptly goes dark and then bright again within a single frame; a bowl's rim appears to break apart and then reform; the camera cuts, zooms, or rotates to a different angle.
level_2: A hand or tool blocks one bowl from view for more than about half a second and the bowl is not shown again clearly afterward; the shadow on one bowl flickers on and off briefly while the other bowl's shadow stays constant; a bowl's shape briefly looks stretched or squashed before snapping back to normal; the shadows cast by the two bowls point in directions that do not match, as if lit from two different light sources.
level_3: Neither bowl teleports, disappears, or is shown from a different camera angle partway through; both bowls stay fully visible for the whole video; the overall brightness and color of the lighting stays the same from start to finish; shadows fall in a direction consistent with a single, unmoving light source; neither bowl nor its dough bends or breaks in a way solid dough and the bowl material could not; the kneading and placement actions unfold as one continuous, physically believable sequence.
level_4: Everything at the 3-point level applies, AND the hands kneading the dough move in a natural, arm-like arc rather than sliding linearly or appearing to float independently of a body; the dough visibly compresses and springs back slightly where the hands press into it; neither bowl shows flicker or doubled edges from one frame to the next; hands passing near a bowl cast and lose contact shadows in a way consistent with their actual distance from the bowl's surface.
level_5: Everything at the 4-point level applies, AND every motion (kneading, placing the bowls, dough rising) proceeds smoothly with no visible speeding up, slowing down, or jumpy stalling; the softness or sharpness of the shadow edges stays consistent throughout rather than changing randomly; no colored fringing or lens-flare-like glow appears around either bowl; the relative depth cues between the two bowls (e.g., which one looks slightly larger or more in focus) stay consistent for the whole video.