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From avocados to raw fish: 10 items to choose in the store

These 10 grocery delivery items to avoid, from ripe avocados to raw fish, are worth choosing in person because freshness, ripeness and fragility are hard to judge online

Online grocery shopping hands the act of choosing food to someone else. A shopper working for Instacart, Walmart $WMT or Amazon $AMZN Fresh walks the aisles, pulls items off shelves and packs them for the trip to your door. For canned soup, rice, pasta and paper towels, that trade costs almost nothing. A box of cereal is the same box no matter who picks it up.

The arrangement gets harder with food that is judged by touch, smell or timing. An avocado that yields to gentle pressure is one example. A melon that smells sweet at one end and a fillet with firm, glossy flesh are others. Each calls for a decision made in front of the product. An app's product page conveys none of it. The person filling the order may also have different standards, or a different meal in mind, than the person who will eat the food.

Most grocery delivery items to avoid share one of three problems. The first is ripeness and freshness, which change from one piece of produce to the next and cannot be read from a screen. The second is time out of refrigeration. Raw meat, poultry and frozen desserts travel through a store, a car and sometimes a doorstep before reaching a fridge or freezer. The third is physical damage. Heavy items packed on top of light ones can crack eggs, break glass jars and flatten bread.

Substitutions add another layer. When a store is out of an item, many services let the shopper swap in something similar. That works for a brand of canned tomatoes. It works less well for a specific cut of deli turkey or a particular kind of fish.

The 10 items below are a selection of groceries that tend to fare poorly in delivery, not a ranked or complete list. Each slide explains what goes wrong with that item and what a shopper checks for when buying it in person. Some of the advice applies at home, too, for anyone who chooses delivery for convenience. Knowing what to look for makes it easier to spot a problem at the door and report it, rather than discover it at dinner time.

Avocados need a firmness check for ripeness

An avocado's ripeness is judged by touch, and a delivery order removes that step. Fruit chosen by someone else can arrive rock hard or soft and brown inside. That gap matters most when the avocado is meant for a specific meal.

The standard in-store check is a light squeeze. A ripe avocado yields slightly when it is cradled in the palm and pressed lightly, without leaving a dent. Fingertips can bruise the flesh. Using the whole hand spreads the pressure and avoids that damage. A fruit that feels as firm as a stone needs more time. One that feels mushy or has sunken spots is likely past its best.

The stem cap offers a second clue. That small nub at the top of the fruit can often be flicked off with a thumb. Green flesh underneath usually signals a ripe avocado. Brown flesh underneath points to fruit that has gone too far. A cap that refuses to budge generally means the avocado is still unripe.

Skin color helps only with certain varieties. Hass, the dark, pebbly-skinned avocado common in U.S. and U.K. supermarkets, turns from green toward purplish black as it ripens. Smooth-skinned green varieties such as Fuerte can stay green even when they are ready to eat. For those, feel and the stem cap are the better guides.

Avocados do not ripen on the tree. They begin to soften only after they are picked. A hard avocado left at room temperature will ripen over several days. Placing it in a paper bag with an apple or a banana speeds the process. Once it is ripe, moving it to the refrigerator slows further softening.

Timing is the core delivery problem. Guacamole planned for that evening needs fruit that is ready now. A sandwich later in the week works better with a firmer avocado. Shopping in person lets a buyer pick a mix, with one ready today and two for later. A remote picker cannot know that plan unless the order spells it out. Even then, the result rests on one person's judgment of feel.

Bananas arrive at the picker's color stage

Bananas move from green to yellow to brown-spotted over a few days, and the stage that suits one household may not suit another. When a delivery shopper fills the order, that person decides which stage lands on your counter.

The difference between stages affects more than appearance. A green banana is firm and starchy, with a mild, slightly astringent taste. As the fruit ripens, much of that starch converts to sugar. The flesh softens, the flavor sweetens, and the peel turns fully yellow. Brown freckles appear next, and the inside becomes softer still.

Each stage suits a different plan. A bunch with green tips works for someone who wants to eat one banana a day across the week. Fully yellow fruit is ready to eat now. Heavily spotted bananas are the usual choice for banana bread, muffins, pancakes and smoothies, where soft, sweet flesh mashes easily.

A remote shopper has no way of knowing which of these plans you have. One order might bring a bunch that is still hard and green when you wanted a snack that afternoon. Another might bring spotted fruit that has to be baked or frozen within a day or two. Many delivery apps include a notes field for requests like "slightly green." The result still depends on what is in the bin and how the shopper reads the instruction.

In a store, the choice is yours. Some shoppers pick up two small bunches at different stages — one ready now and one for later in the week. That staggered approach is hard to request through an app.

Bananas keep ripening after harvest........

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