Use a character vector to count occurrences per row, in a data frame with rows of text, like a dictionary lookup, but with a very specific custom dictionary

dictionary_lookup.R

library(usdanutrients)
library(tidyverse)

foods_simple <- 
	food %>% 
	separate(food, into = str_glue('V{1:11}'), sep = ",") %>% 
	distinct(V1) %>% 
	mutate(V1 = tolower(V1))  %>% 
	mutate(V1 = str_replace_all(V1, "[[:punct:]]", "")) %>% 
	rename(food = V1)

words_about_foods <- 
	data_frame(item = 1:2,
						 words = c("You should eat chocolate, candies and, cake infrequently",
						 					"You should each spinach, potatoes, and broccoli often")
	)

xx <- 
words_about_foods %>% 
	nest(-item) %>% 
	mutate(word = map(data,  ~unlist(str_split(.x$words, " ")))) %>% 
	unnest(word) %>% 
	mutate(word = tolower(str_replace_all(word, "[[:punct:]]", ""))) %>% 
	inner_join(foods_simple, by = c("word" = "food")) %>% 
	group_by(item, word) %>% 
	tally() %>% 
	spread(item, n)
  
  # A tibble: 6 x 3
  word        `1`   `2`
  <chr>     <int> <int>
1 broccoli     NA     1
2 cake          1    NA
3 candies       1    NA
4 chocolate     1    NA
5 potatoes     NA     1
6 spinach      NA     1