Heat-Moisture Treatment (HMT)
Inquiry
What Is Heat-Moisture Treatment (HMT)?
HMT denatures starch by heating it in water with a low content (<35%, w/w) for a certain time at a temperature higher than the gelatinization temperature. Since the low moisture is not enough for gelatinizing, the integrity of the granules is maintained. Many factors influence the effect of HMT, including moisture content, treating temperature, and time, as well as starch characteristics such as plant source, amylose content, etc. The specific process parameters vary greatly reported by different articles.
Table 1. Different heat-moisture treatment conditions in different reports. (Fonseca, et al., 2021)
| Starch |
HMT parameters |
Reference |
| Temperature (°C) |
Time (min) |
Moisture content (%) |
| Sago and arenga |
120 |
60, 90 |
20 |
Adwiyah et al. (2017) |
| Cassava |
120 |
60 |
10, 20, 30 |
Andrade et al. (2014) |
| Grain paddy rice and rice starch |
120 |
10, 30, 60 |
13 |
Arns et al. (2015) |
| Potato |
110 |
60 |
12, 15, 18, 21, 24 |
Bartz et al. (2017) |
| Mango kernels |
110 |
180 |
20, 25, 30 |
Bharti et al. (2019) |
| Potato |
100, 120 |
120 |
30, 35 |
Brahma and Sit (2020) |
| Germinated brown rice grain |
100 |
60 |
30 |
Chung et al. (2012) |
| Green Prata banana |
102 |
60 |
10, 20, 25 |
Costa et al. (2019) |
| Black rice |
100 |
960 |
30 |
Dhull et al. (2021) |
| Rice, cassava, and pinhão starches |
100, 120 |
120 |
22 |
Klein et al. (2013) |
| Avocado |
120 |
60 |
10, 20, 30 |
Lacerda et al. (2015) |
| Corn |
110 |
960 |
20, 25, 30 |
Liu et al. (2016) |
| Potato and sweet potato |
121 |
60 |
35 |
Oliveira et al. (2018) |
| Sweet potato |
110 |
180, 240, 300 |
10, 15, 20 |
Pranoto et al. (2014) |
| Rice bean |
110 |
960 |
25 |
Thakur et al. (2021) |
| Germinated-black rice |
90 |
60, 120 |
25, 30 |
Wattananapakasem et al. (2021) |
| Mung bean |
120 |
120, 240, 360, 480, 600, 720 |
30 |
Zhao et al. (2020) |
Advantages of Heat-Moisture Treated Starch
The benefits of HMT are obvious that the modified starch will be more stable and thus easier to process and use, and that it will be more water-absorbent and thus more suitable for food and beverage production. In addition, HMT makes the starch more viscous, which is more suitable for making various adhesives and glues. Importantly, the mechanical properties are enhanced and water vapor permeability is reduced by HMT, making starch suitable in food package industries and the production of biodegradable films.
Fig.1 HMT of wheat starch and its application in noodles. (Wang, et al., 2023)
Our Services
The most used HMT methods at CD BioGlyco are cooking and drying.
- Cooking: Starch is added to hot water and then heated to be modified.
- Drying: Starch is placed in hot and dry air and then heated to be modified.
The morphology, gelatinization, thermal properties, and crystallization are obviously affected by HMT. The amylose/amylopectin molecules reorganize and the structure changes greatly, which results in the alteration of physical, chemical, and rheological properties. CD BioGlyco guarantees the timely delivery of heat-moisture treated starch that meets customers' specific needs in all its properties.
- Morphological properties: Water content, processing time, and plant source are the determinants of HMT to promote morphology variation of starch particles. Exceeded water may result in partial gelatinization and agglomeration.
- Solubility and swelling capacity: HMT usually reduces swelling capacity, amylose leaching, and viscosity, resulting from the repositioning of bonds and restructuring of starch chains. To improve the effect of HMT, the repeated HMT (RHMT) method has been studied.
- Pasting properties: HMT improves the shear resistance of starch, and increases the gelatinization temperature.
- Crystallinity: HMT may disrupt crystallites and alter the crystalline orientation.
- Thermal performance: HMT results in the formation of a stable configuration, thereby improving the thermal stability of starch.
- Enzymatic digestibility: HMT can increase the content of resistant starch and slowly digestible starch, reduce the digestion and degradation, and thus improve the nutritional value of foods made in starch.
Publication
Technology: HMT, oxidization modification
Journal: Polymers
IF: 5.0
Published: 2023
DOI: 10.3390/polym15092046
Background: The application of biopolymer-based packaging has made great achievements in solving the environmental problems caused by plastic packaging. Starch is the most common biodegradable packaging material. Chemical (oxidation) and physical (HMT) methods were used to modify starch in this study, and their properties for preparing films were tested.
Results: After the starch was denatured by HMT and oxidation, the tensile strength and Young's modulus of the film were both increased, and the elongation of the HMT film was higher, whereas that of the oxidized starch-based film was the opposite. In terms of transparency, the transparency of the HMT film decreased, which may be caused by high temperature during the modification process, while the oxidized starch-based film exhibited higher transparency.
Fig.2 Appearance of cassava-based edible films containing various concentrations of cinnamon essential oil. (Cahyana, et al., 2023)
Applications
- Starch-based foods: Used in parboiled rice, noodles, and bread to improve taste and nutritional value
- Nanocrystals with high thermal stability
- Biodegradable films and food packages
Advantages
- Optional HMT process
- Visible high-quality products
- Intimate after-sales service
CD BioGlyco has specialized in the process of starch modification, with rich experience and scientific, rigorous technical routes. We also provide other Physical Modification services of starch, corresponding Chemical Modification, Enzymatic Modification, and Genetical Modification services. If you are interested in our Starch Manufacture Service, please contact us for detailed information.
References
- Fonseca, L.M.; et al. Physical modification of starch by heat-moisture treatment and annealing and their applications: A review. Carbohydrate Polymers. 2021, 274: 118665.
- Wang, H.W.; et al. Insights into the aggregation structure and physicochemical properties of heat-moisture treated wheat starch and its associated effects on noodle quality. Journal of Cereal Science. 2023, 112: 103704.
- Cahyana, Y.; et al. Properties comparison of oxidized and heat moisture treated (HMT) starch-based biodegradable films. Polymers. 2023, 15(9): 2046.
For research use only. Not
intended for any clinical use.
Related Services
