One of the crucial elements in developing or reformulating product is to maintain the quality throughout its entire shelf life. This study aims to determine the effect of different cooking time on the almond milk-based of lemak cili api gravy. Various cooking times of 5, 10, 15, 20, 25 and 30 minutes were employed to the almond milk-based lemak cili api gravy followed by determination of their effects on physical properties such as total soluble solids content, pH and colour. pH was determined by using a pH meter. Refractometer was used to evaluate the total soluble solids content of almond milk-based lemak cili api gravy. The colours were determined by using spectrophotometer which expressed as L*, a* and b* values. Results showed that almond milk-based lemak cili api gravy has constant values of total soluble solids with pH range of 5 to 6, which can be classified as low acid food. Colour analysis showed that the lightness (L*) and yellowness (b*) are significantly increased while redness (a*) decreased. In conclusion, this study shows that physical properties of almond milk-based lemak cili api gravy changes by increasing the cooking time

A. Talip, Balkis

Abdullah, Norazlin

Muhammad, Norhayati

Saruan, Nurathirah

UTHM Institutional Repository

Effect of cooking time on physical properties of almond milk-based lemak cili api gravy

One of the crucial elements in developing or reformulating product is to maintain the quality throughout its entire shelf life. This study aims to determine the effect of different cooking time on the almond milk-based of lemak cili api gravy. Various cooking times of 5, 10, 15, 20, 25 and 30 minutes were employed to the almond milk-based lemak cili api gravy followed by determination of their effects on physical properties such as total soluble solids content, pH and colour. pH was determined by using a pH meter. Refractometer was used to evaluate the total soluble solids content of almond milk-based lemak cili api gravy. The colours were determined by using spectrophotometer which expressed as L*, a* and b* values. Results showed that almond milk-based lemak cili api gravy has constant values of total soluble solids with pH range of 5 to 6, which can be classified as low acid food. Colour analysis showed that the lightness (L*) and yellowness (b*) are significantly increased while redness (a*) decreased.  In conclusion, this study shows that physical properties of almond milk-based lemak cili api gravy changes by increasing the cooking time

Journals of Universiti Tun Hussein Onn Malaysia (UTHM)

Journal of Science and Technology, Vol. 10 No. 2 (2018) p. 104-107 
*Corresponding author: norazlinh@uthm.edu.my
2018 UTHM Publisher. All right reserved.         
e-ISSN: 2600-7924/penerbit.uthm.edu.my/ojs/index.php/jst 
Effect of Cooking Time on Physical Properties of Almond Milk-Based 
Lemak Cili Api Gravy 
Nurathirah Saruan, Norazlin Abdullah*, Norhayati Muhammad and Balkis A. Talip
Department of Technology and Natural Resources, Faculty of Applied Sciences and Technology, 
Universiti Tun Hussein Onn Malaysia, Pagoh Educational Hub, 84600 Pagoh, Johor, Malaysia. 
Received 30 September 2017; accepted 30 April 2018; available online 1 August 2018 
1. Introduction
Lemak cili api is a hot and spicy delicacy 
that is popular in Negeri Sembilan [1]. It 
comprises of three main ingredients which are 
turmeric, coconut milk and bird’s eye chillies 
[2]. Combination of other ingredients such as 
onions, lemongrass, and other spices makes a 
perfect blend of fresh concoction that is 
balanced with salt and sugar [3]. Although it 
may consist of different variation and styles 
due to different preference in food, most 
Malay traditional cuisine is believed to have 
same similarities in term of characteristics of 
the food which are strong, spicy and aromatic. 
Commonly, lemak cili api is prepared from 
onion, garlic, lemon grass, bird’s eye chillies, 
ginger, and additive such as salt and sugar by 
blending them all together to obtain a 
homogenous green-yellow paste that provide 
colour, spicy taste and authentic fragrant dish. 
Physical and chemical properties changes in 
food components that are caused by 
temperature changes and closely related to the 
quality of food and acceptance of consumer. 
Thus, it turns into desired qualities as the 
product builds. Food quality on products is 
important for consumer requirements, defined 
in term of physical properties such as 
appearance and colour which influence the 
standard acceptance range and qualities for 
food to assure quality control and assurance of 
food. Variations of processing such as 
cooking, storage, and evaporation will 
influence the overall properties of the final 
product in terms of taste, colour, and texture 
[4]. The changes of colour, pH and total 
soluble solids of lemak cili api gravy after 
being cooked could be related with people in 
different ways due to the influences of scents 
and colours that create feeling to increase 
purchase probability that helps with consumer 
preference [5]. Owing this information, this 
study aims to investigate the effect of cooking 
time on the physical properties of almond 
milk-based lemak cili api gravy representing 
the quality of food and commercialising 
traditional food. 
2. Materials and Methods
Ingredients preparation 
Cane sugar (Gula Prai, MSM Malaysia 
Holding Berhad), salt (STC fine salt, STC 
SUPERB Sdn. Bnd) and Malabar tamarind 
(Asam Jawa Penguin, Kim Loong Huat 
Abstract:  One of the crucial elements in developing or reformulating product is to maintain the quality 
throughout its entire shelf life. This study aims to determine the effect of different cooking time on the 
almond milk-based of lemak cili api gravy. Various cooking times of 5, 10, 15, 20, 25 and 30 minutes were 
employed to the almond milk-based lemak cili api gravy followed by determination of their effects on 
physical properties such as total soluble solids content, pH and colour. pH was determined by using a pH 
meter. Refractometer was used to evaluate the total soluble solids content of almond milk-based lemak cili 
api gravy. The colours were determined by using spectrophotometer which expressed as L*, a* and b* 
values. Results showed that almond milk-based lemak cili api gravy has constant values of total soluble 
solids with pH range of 5 to 6, which can be classified as low acid food. Colour analysis showed that the 
lightness (L*) and yellowness (b*) are significantly increased while redness (a*) decreased.  In conclusion, 
this study shows that physical properties of almond milk-based lemak cili api gravy changes by increasing 
the cooking time. 
Keyword: Colour; lemak cili api; gravy; paste; pH; total soluble solids. 
DOI: https://10.30880/jst.2018.10.02.017
Journal of Science and Technology, Vol. 10 No. 2 (2018) p. 104-107 
 
105 
 
Industries Sdn. Bhd) were purchased from a 
local supermarket (Wellward, in Batu Pahat, 
Malaysia). The remaining ingredients used like 
onion, garlic, turmeric, lemon grass, ginger, 
birds’s eye chillies and almond were bought 
fresh to maintain the quality.  
Almond milk used as substitute for 
coconut milk was extracted by blending the 
whole almond nuts with tap water. All fresh 
ingredients such as onion, garlic, ginger, 
turmeric, lemon grass and birds’s eye chillies 
were sorted, peeled, trimmed, washed and 
weighed according to the recipe in Table 1. 
 
Lemak cili api paste and gravy preparation  
Lemak cili api paste were prepared based 
on an original recipe [6] with some 
modification to reduce the fat source. The 
compositions of lemak cili api paste are given 
in Table 1. Fresh ingredients such as onion, 
garlic, lemon grass, and ginger were peeled 
and homogenised in order to make a 202 g of 
mixture using a knife mill (HR7628/00, 
Philips, Jakarta). 
 Lemak cili api gravy was cooked by using 
a controlled temperature crepe maker machine 
(JB35-2, Star Choice, Russia) and initial 
temperature were set at 70 ℃ for 5 minutes to 
simmer the paste then increase to 140 ℃ as the 
remaining ingredients which are almond milk, 
salt, sugar, tamarind, and water as well as 
lemak cili api paste were added. Physical 
properties of lemak cili api gravy were 
determined at a 5 minute interval for 30 
minutes. 
 
Physical properties determination 
The pH value of 10 ml of homogenised 
almond milk-based lemak cili api gravy was 
measured by using a pH meter (Eutech, 
PH700, USA), which was calibrated with 
standard buffers of pH 4.0, pH 7.0, pH 10.0 
before the measurement [7].  
Total soluble solids (TSS) content of 
almond milk-based lemak cili api gravy was 
measured by using a refractometer (PAL-
BX/RI, ATTAGO, Japan), which was 
calibrated by using distilled water. The surface 
of lens was washed with distilled water and 
dried with paper towel to remove excess water 
then tested with lemak cili api gravy [8]. 
The colours of cooked gravy of almond 
milk-based lemak cili api were determined by 
using spectrophotometer (MiniScanE2, Hunter 
lab, USA). Cleaned petri dish containing the 
almond milk-based lemak cili api gravy was 
placed below the light source and post-
processing L, a and b values were recorded 
[9]. The colour was expressed in CIE Lab 
system L*, a*, and b* values, where L* 
indicate lightness on a 0-100 scale from black 
to white, a* red (+) and green (-), and b* 
yellow (+) and blue (-). 
The volume of almond milk-based lemak 
cili api gravy was measured by using 
measuring cylinder. Almond milk-based lemak 
cili api gravy were measured for initial value 
at a 5 minutes interval for 30 minutes. 
 
Table 1 Formulation of almond milk-based 
lemak cili api paste using selected spices. 
No Ingredient Percentage (%) 
1 Onion 11.08 
2 Garlic 2.77 
3 Turmeric 0.55 
4 Lemon grass 2.22 
5 Bird’s eye chilies 2.77 
6 Malabar tamarind 0.67 
7 Salt 1.11 
8 Sugar 0.11 
9 Ginger 1.11 
10 Almond milk 22.17 
11 Water 55.43 
 Total 100.00 
 
3. Results and Discussion 
 
The changes in pH of almond milk-based 
lemak cili api gravy during 30 minutes 
cooking time are shown in Table 2. Initial 
value of samples at 5 minutes was 6.13 which 
decreased to 5.96 at the end of 30 minutes of 
cooking time. This could be the results of loss 
of chlorophyll of certain ingredients due to 
heating process that affect its stability [10]. In 
addition, the degradation of bioactive 
compounds in vegetables may occur during 
cooking process, causing change in physical 
characteristics and chemical composition [11]. 
The reduction of volume affected by 
evaporation process during cooking time may 
also contribute to the changes of the samples 
(Table 2). When comparing the pH value, it 
constantly decreases at 5, 10 and 25 minutes of 
cooking time, the content of pH value were 
significant (p < 0.05) at 5, 25 and 30 minutes 
of cooking time. This shows that almond milk-
based lemak cili api is classified as a low acid 
Journal of Science and Technology, Vol. 10 No. 2 (2018) p. 104-107 
 
106 
 
canned food due to its pH of 5-6 and water 
activity greater than 0.85 [12].  
Table 2 also shows the changes in TSS 
content. Approximately 7.25-8.05% of TSS 
changes had showed at 5 to 30 minutes of 
cooking time. However, the changes of TSS 
were slightly increased at minute 10 (7.25%) 
and 15 (8.05%) during the process. This result 
showed similar finding by Khan (2007) which 
has studied on the heat treatment process of 
the orange fruit for 15 minutes at 50 oC.  The 
study had shown that the heat treatment slows 
down the ripening process and delaying 
soluble solid increment [13]. The same study 
had also determined that the amount of TSS 
gradually increased during storage for 60 days 
(8.66%). TSS corresponds with temperature 
applied on food is based on a study by Kurca 
[14] on black carrot. The anthocyanin 
properties that are highly reactive causes 
increase in solid content during heating as 
reacting molecules become closer when the 
product is concentrated [15]. 
Colour evaluation on the almond milk-
based lemak cili api gravy was done as the 
heat treatment with temperature more than 60 
℃ causes pigment destruction that is expressed 
in term of colour parameter L*, a* and b* 
values [16]. L* value for gravy shows a high 
scale in lightness which ranging from 61.18-
55.41 for 30 minutes of cooking duration. 
Meanwhile, for a* (green) and b* (yellowness) 
values, it shows a* have higher negative value 
(green) (-6.06 until -4.42) as for b* value have 
higher positive value (yellowness) ranging 
from 37.44 to 42.32, respectively. The main 
colorant affect in almond milk-based lemak 
cili api gravy was due to the incorporation of 
turmeric (curcumin) that gives yellow colour 
to the gravy as well as due to acid that 
neutralises the pH value range [17]. A study 
by Weeranakorn [18] on fortification of 
calcium on green curry as an alternative source 
of calcium on traditional food shows a change 
in L* value compared to control with higher b* 
value which gives it greenish-yellow colour. 
 
Table 2 Physical properties of almond milk-based lemak cili api gravy over cooking time. 
  
Time 
(min) 
pH TSS (%) 
Colour Volume 
(ml) L a b 
5 6.13 ± 0.007a 7.25 ± 0.071c 61.18 ± 0.28a -6.06 ± 0.33c 38.17 ± 2.63ab 990 
10 6.03 ± 0.021bc 7.25 ± 0.071c 57.19 ± 0.55b -5.44 ± 0.06b 42.32 ± 4.53a 970 
15 6.07 ± 0.049ab 8.05 ± 0.071ab 55.69 ± 1.08bc -4.55 ±0.21a 38.42 ± 0.07ab 950 
20 6.04 ± 0.021bc 8.20 ± 0.280a 54.26 ± 0.078c -4.59 ± 0.13a 35.29 ± 1.53b 890 
25 5.92 ± 0.021d 7.70 ± 0.140b 55.53 ± 0.21bc -5.42 ± 0.05b 37.96 ± 0.58ab 840 
30 5.96 ± 0.057cd 7.85 ± 0.210ab 55.41 ± 1.62bc -4.42 ± 0.14a 37.44 ± 1.75ab 820 
Different letters in same column means the value are significantly different (p < 0.05), the mean of a is higher 
than b and c (a > b > c). 
 
4. Conclusion 
 
Cooking time has significant effects on 
pH, TSS and colour of almond milk-based 
lemak cili api gravy. TSS value increased 
slightly over cooking time. Heat may increase 
the L* value of lemak cili api gravy due to the 
degradation of colour of ingredients such as 
turmeric and bird’s eye chilllies. This study 
leads to the investigation of factors that may 
affect the quality of food due to cooking 
process.   
 
Acknowledgements  
 
The authors would like to thank the Universiti 
Tun Hussein Onn Malaysia for research 
facilities and its financial support under Short 
Term Grant with project number U538. 
 
References 
 
[1] Brissenden, R. (2007). Southeast Asian 
Food: Classic and Modern Dishes from 
Indonesia,  Malaysia, Singapore, 
Thailand, Laos, Cambodia, and 
Vietnam. Tuttle Publishing, USA. 
[2] Betty. S (2005). Best of Malaysian 
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Marshall International (Asia) Private 
Limited, Singapore 
[3] Uhl. S.R. (2000). Hand Book of Spices, 
Seasonings, and Flavorings. Technomic 
publication company, Inc. USA.  
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[4] Canela, M.A. Alvarez, E, and Maceiras. 
R. (2005). “Rheological Behaviour of 
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Eurotherm Seminar 77- Heat and Mass 
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[5] Kotler, P. (1973), “Atmospherics as a 
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[6] Karangkraf (2001), 50 Ayam. Kompilasi 
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edu/ extension_curall/1110 
[8] Aoun. A.B, (2013). “Evaluation of Fruit 
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Antioxidant Capacity and Color of Thai 
Red Curry Paste” in Natural Science, 
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English

Effect of Cooking Time on Physical Properties of Almond Milk-Based Lemak Cili Api Gravy

One of the crucial elements in developing or reformulating product is to maintain the quality throughout its entire shelf life. This study aims to determine the effect of different cooking time on the almond milk-based of lemak cili api gravy. Various cooking times of 5, 10, 15, 20, 25 and 30 minutes were employed to the almond milk-based lemak cili api gravy followed by determination of their effects on physical properties such as total soluble solids content, pH and colour. pH was determined by using a pH meter. Refractometer was used to evaluate the total soluble solids content of almond milk-based lemak cili api gravy. The colours were determined by using spectrophotometer which expressed as L*, a* and b* values. Results showed that almond milk-based lemak cili api gravy has constant values of total soluble solids with pH range of 5 to 6, which can be classified as low acid food. Colour analysis showed that the lightness (L*) and yellowness (b*) are significantly increased while redness (a*) decreased. Â In conclusion, this study shows that physical properties of almond milk-based lemak cili api gravy changes by increasing the cooking time

Journal of Science and Technology, Vol. 10 No. 2 (2018) p. 104-107 *Corresponding author: norazlinh@uthm.edu.my2018 UTHM Publisher. All right reserved.         e-ISSN: 2600-7924/penerbit.uthm.edu.my/ojs/index.php/jst Effect of Cooking Time on Physical Properties of Almond Milk-Based Lemak Cili Api Gravy Nurathirah Saruan, Norazlin Abdullah*, Norhayati Muhammad and Balkis A. TalipDepartment of Technology and Natural Resources, Faculty of Applied Sciences and Technology, Universiti Tun Hussein Onn Malaysia, Pagoh Educational Hub, 84600 Pagoh, Johor, Malaysia. Received 30 September 2017; accepted 30 April 2018; available online 1 August 2018 1. IntroductionLemak cili api is a hot and spicy delicacy that is popular in Negeri Sembilan [1]. It comprises of three main ingredients which are turmeric, coconut milk and bird’s eye chillies [2]. Combination of other ingredients such as onions, lemongrass, and other spices makes a perfect blend of fresh concoction that is balanced with salt and sugar [3]. Although it may consist of different variation and styles due to different preference in food, most Malay traditional cuisine is believed to have same similarities in term of characteristics of the food which are strong, spicy and aromatic. Commonly, lemak cili api is prepared from onion, garlic, lemon grass, bird’s eye chillies, ginger, and additive such as salt and sugar by blending them all together to obtain a homogenous green-yellow paste that provide colour, spicy taste and authentic fragrant dish. Physical and chemical properties changes in food components that are caused by temperature changes and closely related to the quality of food and acceptance of consumer. Thus, it turns into desired qualities as the product builds. Food quality on products is important for consumer requirements, defined in term of physical properties such as appearance and colour which influence the standard acceptance range and qualities for food to assure quality control and assurance of food. Variations of processing such as cooking, storage, and evaporation will influence the overall properties of the final product in terms of taste, colour, and texture [4]. The changes of colour, pH and total soluble solids of lemak cili api gravy after being cooked could be related with people in different ways due to the influences of scents and colours that create feeling to increase purchase probability that helps with consumer preference [5]. Owing this information, this study aims to investigate the effect of cooking time on the physical properties of almond milk-based lemak cili api gravy representing the quality of food and commercialising traditional food. 2. Materials and MethodsIngredients preparation Cane sugar (Gula Prai, MSM Malaysia Holding Berhad), salt (STC fine salt, STC SUPERB Sdn. Bnd) and Malabar tamarind (Asam Jawa Penguin, Kim Loong Huat Abstract:  One of the crucial elements in developing or reformulating product is to maintain the quality throughout its entire shelf life. This study aims to determine the effect of different cooking time on the almond milk-based of lemak cili api gravy. Various cooking times of 5, 10, 15, 20, 25 and 30 minutes were employed to the almond milk-based lemak cili api gravy followed by determination of their effects on physical properties such as total soluble solids content, pH and colour. pH was determined by using a pH meter. Refractometer was used to evaluate the total soluble solids content of almond milk-based lemak cili api gravy. The colours were determined by using spectrophotometer which expressed as L*, a* and b* values. Results showed that almond milk-based lemak cili api gravy has constant values of total soluble solids with pH range of 5 to 6, which can be classified as low acid food. Colour analysis showed that the lightness (L*) and yellowness (b*) are significantly increased while redness (a*) decreased.  In conclusion, this study shows that physical properties of almond milk-based lemak cili api gravy changes by increasing the cooking time. Keyword: Colour; lemak cili api; gravy; paste; pH; total soluble solids. DOI: https://10.30880/jst.2018.10.02.017Journal of Science and Technology, Vol. 10 No. 2 (2018) p. 104-107  105  Industries Sdn. Bhd) were purchased from a local supermarket (Wellward, in Batu Pahat, Malaysia). The remaining ingredients used like onion, garlic, turmeric, lemon grass, ginger, birds’s eye chillies and almond were bought fresh to maintain the quality.  Almond milk used as substitute for coconut milk was extracted by blending the whole almond nuts with tap water. All fresh ingredients such as onion, garlic, ginger, turmeric, lemon grass and birds’s eye chillies were sorted, peeled, trimmed, washed and weighed according to the recipe in Table 1.  Lemak cili api paste and gravy preparation  Lemak cili api paste were prepared based on an original recipe [6] with some modification to reduce the fat source. The compositions of lemak cili api paste are given in Table 1. Fresh ingredients such as onion, garlic, lemon grass, and ginger were peeled and homogenised in order to make a 202 g of mixture using a knife mill (HR7628/00, Philips, Jakarta).  Lemak cili api gravy was cooked by using a controlled temperature crepe maker machine (JB35-2, Star Choice, Russia) and initial temperature were set at 70 ℃ for 5 minutes to simmer the paste then increase to 140 ℃ as the remaining ingredients which are almond milk, salt, sugar, tamarind, and water as well as lemak cili api paste were added. Physical properties of lemak cili api gravy were determined at a 5 minute interval for 30 minutes.  Physical properties determination The pH value of 10 ml of homogenised almond milk-based lemak cili api gravy was measured by using a pH meter (Eutech, PH700, USA), which was calibrated with standard buffers of pH 4.0, pH 7.0, pH 10.0 before the measurement [7].  Total soluble solids (TSS) content of almond milk-based lemak cili api gravy was measured by using a refractometer (PAL-BX/RI, ATTAGO, Japan), which was calibrated by using distilled water. The surface of lens was washed with distilled water and dried with paper towel to remove excess water then tested with lemak cili api gravy [8]. The colours of cooked gravy of almond milk-based lemak cili api were determined by using spectrophotometer (MiniScanE2, Hunter lab, USA). Cleaned petri dish containing the almond milk-based lemak cili api gravy was placed below the light source and post-processing L, a and b values were recorded [9]. The colour was expressed in CIE Lab system L*, a*, and b* values, where L* indicate lightness on a 0-100 scale from black to white, a* red (+) and green (-), and b* yellow (+) and blue (-). The volume of almond milk-based lemak cili api gravy was measured by using measuring cylinder. Almond milk-based lemak cili api gravy were measured for initial value at a 5 minutes interval for 30 minutes.  Table 1 Formulation of almond milk-based lemak cili api paste using selected spices. No Ingredient Percentage (%) 1 Onion 11.08 2 Garlic 2.77 3 Turmeric 0.55 4 Lemon grass 2.22 5 Bird’s eye chilies 2.77 6 Malabar tamarind 0.67 7 Salt 1.11 8 Sugar 0.11 9 Ginger 1.11 10 Almond milk 22.17 11 Water 55.43  Total 100.00  3. Results and Discussion  The changes in pH of almond milk-based lemak cili api gravy during 30 minutes cooking time are shown in Table 2. Initial value of samples at 5 minutes was 6.13 which decreased to 5.96 at the end of 30 minutes of cooking time. This could be the results of loss of chlorophyll of certain ingredients due to heating process that affect its stability [10]. In addition, the degradation of bioactive compounds in vegetables may occur during cooking process, causing change in physical characteristics and chemical composition [11]. The reduction of volume affected by evaporation process during cooking time may also contribute to the changes of the samples (Table 2). When comparing the pH value, it constantly decreases at 5, 10 and 25 minutes of cooking time, the content of pH value were significant (p < 0.05) at 5, 25 and 30 minutes of cooking time. This shows that almond milk-based lemak cili api is classified as a low acid Journal of Science and Technology, Vol. 10 No. 2 (2018) p. 104-107  106  canned food due to its pH of 5-6 and water activity greater than 0.85 [12].  Table 2 also shows the changes in TSS content. Approximately 7.25-8.05% of TSS changes had showed at 5 to 30 minutes of cooking time. However, the changes of TSS were slightly increased at minute 10 (7.25%) and 15 (8.05%) during the process. This result showed similar finding by Khan (2007) which has studied on the heat treatment process of the orange fruit for 15 minutes at 50 oC.  The study had shown that the heat treatment slows down the ripening process and delaying soluble solid increment [13]. The same study had also determined that the amount of TSS gradually increased during storage for 60 days (8.66%). TSS corresponds with temperature applied on food is based on a study by Kurca [14] on black carrot. The anthocyanin properties that are highly reactive causes increase in solid content during heating as reacting molecules become closer when the product is concentrated [15]. Colour evaluation on the almond milk-based lemak cili api gravy was done as the heat treatment with temperature more than 60 ℃ causes pigment destruction that is expressed in term of colour parameter L*, a* and b* values [16]. L* value for gravy shows a high scale in lightness which ranging from 61.18-55.41 for 30 minutes of cooking duration. Meanwhile, for a* (green) and b* (yellowness) values, it shows a* have higher negative value (green) (-6.06 until -4.42) as for b* value have higher positive value (yellowness) ranging from 37.44 to 42.32, respectively. The main colorant affect in almond milk-based lemak cili api gravy was due to the incorporation of turmeric (curcumin) that gives yellow colour to the gravy as well as due to acid that neutralises the pH value range [17]. A study by Weeranakorn [18] on fortification of calcium on green curry as an alternative source of calcium on traditional food shows a change in L* value compared to control with higher b* value which gives it greenish-yellow colour.  Table 2 Physical properties of almond milk-based lemak cili api gravy over cooking time.   Time (min) pH TSS (%) Colour Volume (ml) L a b 5 6.13 ± 0.007a 7.25 ± 0.071c 61.18 ± 0.28a -6.06 ± 0.33c 38.17 ± 2.63ab 990 10 6.03 ± 0.021bc 7.25 ± 0.071c 57.19 ± 0.55b -5.44 ± 0.06b 42.32 ± 4.53a 970 15 6.07 ± 0.049ab 8.05 ± 0.071ab 55.69 ± 1.08bc -4.55 ±0.21a 38.42 ± 0.07ab 950 20 6.04 ± 0.021bc 8.20 ± 0.280a 54.26 ± 0.078c -4.59 ± 0.13a 35.29 ± 1.53b 890 25 5.92 ± 0.021d 7.70 ± 0.140b 55.53 ± 0.21bc -5.42 ± 0.05b 37.96 ± 0.58ab 840 30 5.96 ± 0.057cd 7.85 ± 0.210ab 55.41 ± 1.62bc -4.42 ± 0.14a 37.44 ± 1.75ab 820 Different letters in same column means the value are significantly different (p < 0.05), the mean of a is higher than b and c (a > b > c).  4. Conclusion  Cooking time has significant effects on pH, TSS and colour of almond milk-based lemak cili api gravy. TSS value increased slightly over cooking time. Heat may increase the L* value of lemak cili api gravy due to the degradation of colour of ingredients such as turmeric and bird’s eye chilllies. This study leads to the investigation of factors that may affect the quality of food due to cooking process.    Acknowledgements   The authors would like to thank the Universiti Tun Hussein Onn Malaysia for research facilities and its financial support under Short Term Grant with project number U538.  References  [1] Brissenden, R. (2007). Southeast Asian Food: Classic and Modern Dishes from Indonesia,  Malaysia, Singapore, Thailand, Laos, Cambodia, and Vietnam. Tuttle Publishing, USA. [2] Betty. S (2005). Best of Malaysian Cooking. Marshall Cavendish Cuisine. Marshall International (Asia) Private Limited, Singapore [3] Uhl. S.R. (2000). 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Effect of cooking time on physical properties of almond milk-based lemak cili api gravy

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