Switching every familiar grocery product at once makes it difficult to learn anything useful. If the household dislikes dinner, you may not know which change caused the problem. A more informative approach is to try a store brand in one ordinary purchase while keeping the rest of the meal familiar.
Choose a product with a clear job. Plain pasta, canned tomatoes, or a breakfast cereal can be easier to assess than an ingredient used only on a special occasion. Compare similar versions and check the package quantity. A cheaper shelf price is less impressive if the alternative contains less food, requires additional ingredients, or differs in a way that matters to the people eating it.
Read the ingredient list and relevant label information before buying. A store label does not establish that two products have the same recipe or are made in the same factory. Avoid assuming equivalence from package colour or shape. If someone in your household has dietary requirements, use the information appropriate to those requirements rather than treating price as the deciding factor.
Run a useful household comparison
For example, try the alternative canned tomatoes in a sauce you already make. Use your usual method so the comparison is reasonably understandable. Notice flavour, consistency, ease of opening, and whether you need more of the product to reach the desired result. This is a suggested exercise, not a claim that any particular brand has been tested or performs equally well.
Ask a practical question after the meal: would we happily use this again at its normal price? The answer can be different for different products. You might prefer the cheaper pasta and keep your favourite coffee. A mixed basket is a reasonable outcome; there is no benefit in maintaining loyalty to either premium labels or store labels as a principle.
Avoid stockpiling the trial product simply because the first package is on promotion. Buy enough to evaluate it and check the ordinary price before adopting it. A temporary offer can make the test inexpensive without establishing the long-term value of the switch.
Keep the decision easy to reverse
Record a short note if it helps: acceptable for sauce, preferred for breakfast, or not worth repeating. You do not need a formal rating system. The useful information is the situation in which the product works and whether its price advantage survives a fair quantity comparison.
Repeat the process with another frequent purchase only when you are ready. Small experiments limit disappointment and spread the effort across normal shopping trips. Over time, they can produce a basket chosen for actual preferences and useful value, without requiring the household to accept every cheaper substitute.