Here is a response I received from Butternut Box regarding this research-obviously their comments relate specifically to their own food but it does echo a lot of the information contained in the Dr Karen Becker article shared by Seaweed. Hopefully it may be useful to other forum members

"Recently, The U.S. Food and Drug Administration issued an alert to pet owners and veterinary professionals about reports of canine dilated cardiomyopathy (DCM) in dogs eating certain pet foods containing peas, lentils, other legume seeds, or potatoes as main ingredients.
Diets in cases reported to the FDA frequently list potatoes or multiple legumes such as peas, lentils, other “pulses” (seeds of legumes), and their protein, starch and fibre derivatives early in the ingredient list, indicating that they are main ingredients. It is not yet known how these ingredients are linked to cases of DCM.
Previous other studies have linked very high fibre, lamb and rice foods (that is, lamb and rice fed together), and very low protein diets to this DCM heart condition.
Studies have also found that animals fed heat processed diets have lower taurine concentrations that animals fed non-heat processed diets. This is thought to be related to the Maillard cooking reaction. The Maillard reaction is a chemical reaction that gives food its browning colour and occurs with rapid heating at temperatures above 140°C.
Our meals’ main ingredient is 60% high-quality fresh meat and 40% pulses, vegetables, seeds and botanicals. Of this 40%, 10% of our ingredients are lentils and 7% are peas.
Lentils are a rich source of protein, B vitamins, iron and soluble fibre. Iron is an essential nutrient, meaning you must get it from food. Iron carries oxygen in blood around the body and is needed to support red blood cells. Fibre does more than just keep your dog regular. Evidence shows that diets higher in this ruff stuff slows down the rate of digestion, leading to a slower absorption of glucose and regulates blood sugar levels.
Based on research and the advice of our vet nutritionists, we choose to add fresh vegetables, herbs and seeds to our food to provide a balanced diet, rich in vitamins, omega fatty acids and antioxidants.
Taurine is found in red meats, heart, liver, dark white meats (i.e. the dark meat of chicken and turkey), white fish and shellfish. Our meals contain 60% meat from a combination of prime muscle, heart and liver.
As we gently cook our meals at low temperatures (90°C), the Maillard reaction does not occur."
Our veterinary nutritionists have assured that due to our high animal-protein content and our gentle cooking process, our meals are rich in available taurine.”