With the rise in consumption of highly processed food products that cause a reduction in dietary fiber, the production and application of resistant starch in food has become a necessity. Today, the starch is applied in various food products, including medical foods and dietary supplements to maintain colon health and integrity of the gut mucosa. In some cases, it may also be used as a medicine.
Recent studies have proved that resistant starch is capable of mitigating colon diseases, and cancer. In addition, it may also cut the occurrence of a series of metabolic syndrome, including insulin resistance, hyperglycaemia, too much blood insulin, dyslipidaemia, abnormal blood fiber dissolution, diabetes, hypertension and cardiovascular disease. Augmenting the capabilities of the starch, researchers have introduced new applications of the starch, for instance, in fat replacers (used for controlling obesity).
Relevance of Resistant Starch
Carbohydrates containing food products, especially cereal-based, potato-based and organs of some tropical plants have starch that provides the organism with necessary energy. Due to the amylolytic enzymes present in the gastro intestine of human beings, starch undergoes hydrolysis resulting in rapid and complete digestion and absorption in the small intestine in the form of glucose (a product of hydrolysis of starch). Some part of consumed starch has been observed to be incompletely digested and in an intact form or as products of its partial hydrolysis to escape the small intestine and enter the large intestine. This part of the starch has been termed “resistant starch” (RS).
In large intestine RS is fermented, producing short chain fatty acids (SCFA) which serve as an energy source for colonic cells. Foods that increase the amount of SCFAs in the colon are thought to be beneficial to health by preventing the development of abnormal cells in the gut.
Since the 2000s, IP filings in this technology domain have increased at an average rate of 12.8% per year, with most patents filed in China followed by the USA and Japan.
Several key factors, such as the rise in health problems and awareness among the people has caused an increase in demand for products. For example, cereal bars having reduced caloric value can lower glucose, blood level and contains high dietary fiber. The introduction of new products, development in science and chemistry behind the starch, introduction of new devices and preparing methods and rise in population drives the the starch market. The market for modified resistant starch is expected to reach nearly $14 billion by 2024.
The most active players in this domain are:
- National Starch & Chemical Investment Holding
- MGP Ingredients
- Tate & Lyle
Overall the patents in the technology domain focus on:
- Improvement in conventional manufacturing methods like pressure-heat treatment, enzymatic or acid-release treatment, extruded treatment, microwave bulking treatment method, an ultrasonic method etc. for making resistant starch from different sources.
- Improvement in properties of resistant starch (temperature resistance, for instance).
- Improvement in method of measuring the content of resistant starch.
- Increment in content of high dietary fiber.
- Reducing the content of chemical substance.
- Reduction in manufacturing cost.
In this domain, patent filings indicated that before the year 2000, inventions were focused particularly on method of manufacturing of resistance starch and chemical change of starch to inhibit its digestibility.
Between the years 2000-2005, majority of the inventions were focused on preparation of resistant starch (especially, type 3) containing acid or an acid salt. During this period, the focus was resistant starch containing alpha amylase.
Between the years 2005-2013, researches started to focus highly on modified starch. For example, pectin-modified resistant starch that is prepared by cross-linking starch with pectin through pectin-esterase reaction. Apart from this, researchers also focus on improving the properties of resistant starch, such as enhanced emulsion stabilities, thermal stability, hot & cold water swelling capacities in water/oil and in other aqueous systems. Several patents focusing on improvement in methods/techniques for preparing, resistant starch (retrograded resistant starch prepared through electrolysis, microwave and ultrasonic method) were also filed during this period. The patents focused on reducing the calorie content and increasing fiber content in food products.
From the year 2014, the focus of the researchers is towards the production of resistant starch without the use of chemical additives, introducing new applications, inclusion of the resistant starch in various food products including cereal bars, rice jellies and other processed foods.
In 2016, China filed patents that focused on using resistant starch in fish balls, beef balls etc. and extracting resistant starch from seaweeds.
New innovative applications and disruptions in the starch technology came into existence in the year 2017. Notable ones are:
- The starch is used as the wall material of the microcapsules so that when it passes through the stomach and small intestines, the core material can be protected from being degraded by gastric juice and small intestines, and probiotics can be released in the large intestines.
- The content of resistant starch in rice is increased and the activity of the SBEIIb protein in the rice can be inhibited at the same time using the CRISPR/Cas9 technology in which the rice SBEIIb genes are edited at fixed points. The rice SBEIIb genes are knocked off by causing frameshift mutation, and the new generation of new rice germplasm with the increased content of amylase and the starch is obtained.
All in all, the patents in this technology domain mainly focus on the starch in rice, banana, chestnut, yam and milk for making products like rice cake, ice cream, biscuits, etc.
Few examples of remaining patent disclosures are: salad dressing containing pea resistant starch, lotus seed resistant starch, corn resistant starch, manihot esculenta resistant starch, chestnut resistant starch, long on seed resistant starch, yam resistant starch, xylitol tea oil resistant starch, biscuits for diabetic patients, gluten-free resistant starch, colourless resistant starch, different methods for extracting resistant starch (such as ultrahigh pressure and ultrasonic assisted treatment), packaging of resistant starch, etc.
R&D in China for Resistant Starch:
The major focus of researchers in China is on manufacturing method of the starch by adopting alpha-amylase, preparation method for esterified resistant starch, preparation method & application of high-temperature-resistant starch-based scale inhibitor, the starch prepared by disbranching of low amylose starch and high fiber cookies containing inulin & resistant starch, and food or drinks using the same.
In China, universities and research institutes are supplied bulk of patents in which Jiangnan University, University Fujian Agriculture & Forestry and Zhejiang University are leading ahead of others.
Among the new entrants that have emerged in this technology domain in the year 2017, most of them belong to China. The notable ones are:
- University Fujian Agriculture & Forestry;
- Zhengzhou Guoshi Technology;
- Maanshan City Huangchi Food; and
- Wuhan Hao Duoduo Biotechnology.
Comment (Resistant Starch)
There are a variety of starches available from plant and other sources out of which only a handful have been studied to realize the full potential of resistant starch. There are also various studies about the effects of these starches in the human body and their effectiveness in prevention and control of diseases.
With the involvement of new innovative technologies like CRISPR/CAS system to enhance properties of resistant starch and bring it up to its full potential, it would be interesting to know how key industries will compete with each other and strengthen their portfolio to answer the questions surrounding this technology. Questions, such as – how can the properties of resistant starch can further be improved, which alternative industries have potential to penetrate the resistance starch market, how the existing major players can collaborate and/or merge with them and what could be the possible applications of resistant starch in food industry without affecting the medication or other food ingredients?
-The Life Sciences and Editorial Team