I'm a little sensitive to this issue because of problems we're dealing with with DS so I'm coming from a view point of food issues that are requiring medical intervention yet having had people dismiss my concerns for a while as 'just a phase'. From what I've learned with my DS, it's at around this age (just after they turn 1) that parents might become aware of food issues but this may be because, at this age, children are starting to try and make their own decisions on some things, and they're also starting to be more independent with feeding themselves food etc. It isn't always a problem, and in many cases can "just" be a phase and something he'll work through himself but there can be times where it is something that parents might need more help with.
If you're really stuck and concerned, try contacting your local community health center and ask if they have an occupational therapist or a speech therapist that are trained in food issues. They will be able to sit down with you and go through your concerns and give you an idea of whether they're 'normal' behaviours or if it's something to be concerned about. If they think it is something to be concerned about they'll be able to work with you to start implementing ideas to help you. I know that, where I am, there are monthly 'drop in clinics' were you just show up and can speak to an OT/speech/physio about concerns as that's what I did with my concerns about my son's eating and they did a brief assessment and decided that my concerns warranted further investigation so we were referred on to a proper scheduled appointment with an OT who we are now seeing to work on getting DS to eat more than a few things.
Some of the strategies that we're using with DS are:
* no serving at the kitchen and then just taking plates to the table. All the food is placed into bowls and then put out on the table. Instead of having things all mixed together e.g. pasta with the topping over the top etc, everything is in it's own bowl and then served from there.
* Everyone serves themselves. I don't dish the food up anymore, although I do help DD2 but that's more so that the food doesn't end up all over the table. Everyone serves themselves and takes as much or as little as they want from each component/container. This way DS, who doesn't like his food to be 'wet' can serve up his Sweet and sour pork into 3 distinct sections on his plate with the rice and meat kept well away from the sauce while I can have everything mixed together.
* Everyone must take a bit of everything onto their plate but that doesn't mean that they have to eat it. DS in particular has his 'learning plate' and his 'eating plate'. He serves onto his eating plate but if he doesn't want to eat it he has to move it onto his learning plate. This encourages him to at least touch the food and interact with it etc. They've also recommended that, at the end of the meal, DS put the food he hasn't attempted to eat (the stuff on his learning plate) into the bin by holding it between his teeth and blowing it, not spitting it, into the bin because this lets him experience the sensation of the food on/in his mouth without having to actually eat it. Personally I just can't bring myself to do this part but I do get him to put his rubbish away etc.
* Every meal has something that I know he'll eat. For a while we stopped using spaghetti when having spaghetti bolognaise because he wouldn't eat the spaghetti and also doesn't eat the sauce. Instead we'd use spiral pasta because it was something we knew he'd eat.
* Take the pressure away from meal times, if he eats he eats, if he doesn't it's ok. The OT explained it to me using the flight or fight response - for DS, when he feels pressure to eat he actually eats less and his appetite decreases even more because he's focused on getting away from the situation as fast as he can. By taking away the pressure of 'you must eat this much' his appetite isn't supressed even more and he's more likely to eat his meal.
* Don't use desserts etc as a reward/loss of desserts as a consequence. If you are planning to have dessert after a meal praise their effort at eating regardless of how much or how little they've actually eaten before giving them the dessert because it is a part of the meal. This one seemed counter intuitive to me when they first said it, I thought that he'd just eat less because he knew he'd still get the dessert after. To my surprise it actually had the opposite effect because it took the pressure away about 'having' to eat the main food and by allowing him to have dessert, when they were planned as part of dinner anyway, regardless of how much he'd eaten of the main meal he actually started eating more of the meal rather than less.
* trying to have a regular routine for meals and snacks. there is some flexibility, it's not like dinner has to be on the table at x time or the world comes to an end but we do try to do things within 30min of a certain time.
* depending on where he sits to eat, make sure his legs are supported. DS sits in a chair but can't reach the floor when sitting down. we know have a little stool thing that sits under the table for him to put his feet on and it helps because he's more comfortable.
Like I said at the start, I'm sensitive to this topic because of my experience so not all of this information may be relevant to you and you may find that it is just him trying to be independent and having some level of control over something but, by the same token, I know that people dismissing my concerns and telling me that it was 'normal' wasn't helpful with what we ended up dealing with.
I hope some of this is helpful.