The primary motivation for this post is to explore options to improve the durability of palm leaf straws and make them last longer in all types of hot and cold beverages. The food grade glue from tapioca starch can hold the structure of the straws for 3 – 4 hours in various types of hot and cold liquids. My research to find a better solution to keep the integrity of the structure of the straw for more than 4 hours using food-grade glue made from pine resin.

Pine tree sap is an excellent raw material to make all-natural glue for the eco-friendly palm leaf straw. The glue made from pine sap is strong, sticky and naturally resistant to water. I have been researching the solubility of pine resin in water at different temperatures to test the durability of the glue. Table 1 below shows the solubility and temperature of the glue from pine resin.

Temperature (degrees Fahrenheit) Time (hours) Soluble (Yes/No)
38 5 No
77 5 No
122 5 No
167 5 No

Based on the experiments with glue made from pine tree sap, the glue does not dissolve in hot liquids until the temperature of the liquid reaches 185 degrees Fahrenheit. Look for my next blog I will use this glue to demonstrate the making of the straw with pine sap glue.

Pictures top row left to right
Collecting sap, Raw sap, Melting
Pictures bottom row left to right
Cooling of sap, sap at 38oF beginning, sap at 38oF after 5 hours