Portion analysis
Serving total and calorie density answer different questions
The listed source amounts run from 250 to 298 grams—a 48-gram gap before composition enters the comparison. Their own source servings run from 303 calories for “whole grain, with tomato-based sauce and meat, home recipe” to 445 for “restaurant.” At a fixed 100 grams, “diet frozen meal” is 113 calories and “restaurant” is 178—a fixed-weight separation of 65 calories. For Pasta with meat sauce, the serving view answers “how much is in the database portion?”; the 100-gram view answers “how concentrated is the matched record?” Neither reveals how many grams were actually eaten.
The scaling rule: multiply a per-100-gram value by eaten grams ÷ 100. The arithmetic is exact; the result is only as defensible as the record match and portion estimate.
Preparation analysis
The long description carries the evidence
The published descriptions distinguish forms such as “whole grain, with tomato-based sauce and meat, home recipe”, “whole grain, with tomato-based sauce and meat, ready-to-heat”, “diet frozen meal”, “whole grain, with tomato-based sauce and meat, restaurant”, and “restaurant”. The source formulations contain 6 distinct ingredient codes; examples that appear in only part of the set include spaghetti sauce with meat, salt, table, vegetable oil, nfs, and pasta, cooked, enriched, without added salt. On this Pasta with meat sauce page, those rows make the records inspectable, but they are not a controlled experiment: they cannot tell us that one named input, by itself, caused a nutrient difference.
Database precision is not meal certainty. Retain the exact description beside the number so later corrections remain possible.