While eating,halfway through a meal sudden onset of mucous production and hiccups. ( almost like an esophageal spasm or allergic reaction, but no pain) unable to eat further, no problem with breathing. no other symptoms, potential etiology?

Those reactions are likely related to the foods you ate, either too spicy or too hot which can trigger the nasal mucous production (rhinorrhea) and hiccups (contraction of the diaphragm, not the esophagus). I doubt if there is any specific pathology. You should make a diary which specifies the foods you eat, contents, spicy or not, temperature, etc. if these symptoms recur.