# Some Physical Properties and Mass Modelling of Pepper Berries (Piper nigrum L.), Variety Kuching, at Different Maturity Levels

^{1}

^{2}

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## Abstract

**:**

## 1. Introduction

## 2. Materials and Methods

#### 2.1. Measurements of Physical Properties

_{g}), and sphericity (Φ) were calculated by using the following respective formulas [5,20,21,22]:

_{L}, PA

_{T}, and PA

_{W}) in three perpendicular directions to the dimensions (major axis, medium axis, and minor axis) and the criteria projected area (CPA) were calculated by using Equations (5)–(8), respectively. These equations were suggested by Mohsenin [4] and Nur Salihah et al. [14] and are defined as follows:

#### 2.2. Regression Analysis and Mass Modelling

- Single variable regression of pepper berry mass based on dimensional characteristics of the pepper berry—major axis (L), medium axis (T), minor axis (W), and geometric mean diameter (D
_{g}). - Single regression of pepper berry volume—actual volume (V).
- Single regression of pepper berry surface area—surface area of the fruit assumed as a spheroid (SA
_{sp}). - Single variable regression of pepper berry projected area —PA
_{L}, PA_{T}, PA_{W}, and CPA_{.}

#### 2.3. Statistical Analysis

^{2}) and standard error of the estimate (SEE) were selected as the criteria to evaluate the applicability of the regression models. The applicable models were selected as those with higher R

^{2}and lower SEE values [21].

## 3. Results and Discussion

#### 3.1. Physical Properties of Pepper Berries

_{g}) of immature pepper berries was 4.85 mm with a standard deviation of 0.38. Mature pepper berries had a mean value of 5.92 mm with a standard deviation of 0.35 for the geometric mean diameter. Furthermore, the mean value of the geometric mean diameter of ripe pepper berries was 5.61 mm with a standard deviation of 0.46. Thus, the mean value of the geometric mean diameter of mature pepper berries was the highest among all three maturity levels.

^{3}± 5.77. The mean actual volume of mature pepper berries was 120 mm

^{3}± 10.00. Furthermore, the ripe mature pepper berries had mean values of 120 mm

^{3}± 21.60 for the actual volume. Overall, the mature and ripe pepper berries had the highest mean actual volumes when compared to the immature pepper berries.

^{2}± 11.43. The mature pepper berries had a mean value of 110.49 mm

^{2}± 13.66 for the spheroid surface area. The mean value of the spheroid surface area of ripe pepper berries was 99.39 mm

^{2}± 16.66. Thus, the highest mean value of the surface area for the spheroid was obtained for mature pepper berries as shown in Table 1.

_{L}), medium axis (PA

_{T}), and minor axis (PA

_{W}). The results obtained for immature pepper berries were 17.78 mm

^{2}± 2.75 (PA

_{L}), 19.04 mm

^{2}± 3.08 (PA

_{T}), and 17.73 mm

^{2}± 2.57 (PA

_{W}). The mean values of PA

_{L}, PA

_{T}, and PA

_{W}for mature pepper berries were 26.50 mm

^{2}± 3.28, 28.51 mm

^{2}± 3.93, and 27.16 mm

^{2}± 3.45, respectively. As for the ripe pepper berries, the mean values were 24.78 mm

^{2}± 4.27, 25.10 mm

^{2}± 4.51, and 25.45 mm

^{2}± 4.56 for PA

_{L}, PA

_{T}, and PA

_{W,}respectively. Therefore, the mature pepper berries had the highest mean values of PA

_{L}, PA

_{T,}and PA

_{W}when compared to the other two maturity levels of pepper berries. The criteria of projected area were determined by using the results of PA

_{L}, PA

_{T}, and PA

_{W}as indicated in Equation (11). The mean values of projected area criteria for immature, mature, and ripe pepper berries were 18.19 mm

^{2}± 2.73, 27.39 mm

^{2}± 3.52, and 25.11 mm

^{2}± 4.13, respectively. Thus, the projected area criteria for mature pepper berries had the highest mean value in Table 1.

#### 3.2. Mass Modelling

^{2}, and SEE to predict mass by using the measured average dimensions, volumes, weight, surface areas, and projected areas of pepper berries. The correlations of physical properties with pepper berry mass as shown from the results obtained were significant at the 0.01 probability level. The regression mass was evaluated by using the coefficient of determination (R

^{2}), where the best fit model was shown with a higher R

^{2}value (near 1.00).

#### 3.3. Models Based on Dimensions

_{g}) showed that the Quadratic model was the best-fit model to calculate and evaluate the mass of immature, mature, and ripe pepper berries. Table 2 shows the fitted models based on dimensions such as L, T, W, and D

_{g}with the values of ${R}^{2}$ and SEE.

_{g}had a highest value of ${R}^{2}$ and the lowest value of SEE, which were 0.938 and 0.002, respectively, as indicated in Table 2. Equation (13) shows the equation of the Quadratic model obtained.

_{g}values with the highest ${R}^{2}$ (0.960) and the lowest SEE (0.001). The model equation obtained for these parameters was Quadratic. Equations (14) and (15) were determined for the parameters W and D

_{g}.

#### 3.4. Models Based on Volume

#### 3.5. Models Based on Surface Area

_{sp}), the Quadratic model was the best based on the highest value of ${R}^{2}$ compared to the other models. For the best fit model, the Quadratic model based on SA

_{sp}of ripe pepper berries had the highest value of ${R}^{2}$ and lowest SEE of the surface area-assumed shape; the respective values were 0.984 and 0.006 (as shown in Equation (22)). It was also the best fit among the models of other maturity levels of pepper berries.

_{sp}which had the highest ${R}^{2}$ of 0.936 and lowest SEE of 0.002 for immature pepper berries (as shown in Equations (23)). The suitable model of immature pepper berries is shown in the following equation:

_{sp}had the highest value of ${R}^{2}$ and lowest SEE, which were 0.960 and 0.001, respectively. The model equation was formed as indicated in Equation (24).

#### 3.6. Models Based on Projected Area

_{L}, PA

_{T}, PA

_{W}, and CPA), the Quadratic model comprising PA

_{T}was the best fit with the highest R

^{2}of 0.71 and lowest SEE of 0.001 for mature pepper berries as shown in Table 4. Equation (25) shows the model equation obtained. The Quadratic model based on PA

_{T}(Equation (26)) was suitable, with R

^{2}of 0.946 and SEE of 0.002, with respect to immature pepper berries. The Quadratic model based on PA

_{W}(Equation (27)) also achieved a suitable R

^{2}of 0.942 with SEE of 0.012 for ripe pepper berries.

^{2}value of 0.966, a model based on CPA (Equation (28)) for ripe pepper berries was found as the best fit with SEE of 0.009. The mature pepper berries had values of R

^{2}and SEE (Equation (29)) which were 0.962 and 0.001, respectively. The immature pepper berries had the lowest R

^{2}and SEE values for the Quadratic model based on CPA (Equation (30)), which were 0.880 and 0.003, respectively, compared to other maturity levels of pepper berries.

## 4. Conclusions

^{2}, 0.995, and lowest SEE, 0.006, when compared to other maturity levels of pepper berries. This shows a very good relationship between the mass and actual volume of pepper berries. The model predicting the mass of pepper berries considered as spheroid was found to be the most applicable (Quadratic model is recommended). Finally, the Quadratic model is applicable to all properties due to its economical viewpoint. The mass model of pepper berries based on actual volume in the obtained results is recommended for designing and optimizing machines for handling, cleaning, conveying, and storing.

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

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Immature | Mature | Ripe | |||||||
---|---|---|---|---|---|---|---|---|---|

Parameter | Mean | Maximum Value | Minimum Value | Mean | Maximum Value | Minimum Value | Mean | Maximum Value | Minimum Value |

L (mm) | 4.75 ± 0.38 ^{c} | 5.50 | 4.00 | 5.73 ± 0.32 ^{a} | 6.60 | 5.40 | 5.55 ± 0.66 ^{b} | 7.40 | 4.36 |

T (mm) | 5.09 ± 0.50 ^{c} | 5.70 | 4.30 | 6.16 ± 0.44 ^{a} | 7.10 | 5.60 | 5.60 ± 0.33 ^{b} | 7.10 | 4.31 |

W (mm) | 4.74 ± 0.34 ^{c} | 5.30 | 4.00 | 5.87 ± 0.34 ^{a} | 6.70 | 5.40 | 5.67 ± 0.51 ^{b} | 7.01 | 4.36 |

AR | 1.00 ± 0.03 ^{a} | 1.04 | 0.96 | 0.98 ± 0.02 ^{a} | 1.00 | 0.93 | 0.98 ± 0.13 ^{a} | 1.18 | 0.79 |

D_{g} (mm) | 4.85 ± 0.38 ^{c} | 5.50 | 4.10 | 5.92 ± 0.35 ^{a} | 6.80 | 5.47 | 5.61 ± 0.46 ^{b} | 7.17 | 4.67 |

Φ | 1.02 ± 0.02 ^{ab} | 1.05 | 0.97 | 1.03 ± 0.02 ^{a} | 1.08 | 1.01 | 1.01 ± 0.08 ^{b} | 1.43 | 0.72 |

Weight (g) | 0.10 ± 0.01 ^{a} | 0.11 | 0.09 | 0.14 ± 0.01 ^{a} | 0.14 | 0.13 | 0.15 ± 0.04 ^{a} | 0.23 | 0.11 |

V (mm^{3}) | 96.67 ± 5.77 ^{b} | 100.00 | 90.00 | 120 ± 10.00 ^{a} | 130.00 | 110.00 | 120 ± 21.60 ^{a} | 140.00 | 90.00 |

SA_{sp} (mm^{2}) | 74.65 ± 11.43 ^{c} | 95.03 | 52.81 | 110.49 ± 13.66 ^{a} | 145.27 | 93.88 | 99.39 ± 16.66 ^{b} | 161.51 | 69.20 |

PA_{L} (mm^{2}) | 17.78 ± 2.75 ^{c} | 22.89 | 12.57 | 26.50 ± 3.28 ^{a} | 34.73 | 22.90 | 24.78 ± 4.27 ^{b} | 40.74 | 17.70 |

PA_{T} (mm^{2}) | 19.04 ± 3.08 ^{c} | 23.73 | 13.51 | 28.51 ± 3.93 ^{a} | 37.36 | 23.75 | 25.10 ± 4.51 ^{b} | 39.09 | 14.96 |

PA_{W} (mm^{2}) | 17.73 ± 2.57 ^{c} | 22.06 | 12.57 | 27.16 ± 3.45 ^{a} | 35.26 | 22.90 | 25.45 ± 4.56 ^{b} | 38.59 | 14.93 |

CPA (mm^{2}) | 18.19 ± 2.73 ^{c} | 22.89 | 12.88 | 27.39 ± 3.52 ^{a} | 35.78 | 23.18 | 25.11 ± 4.13 ^{b} | 39.48 | 16.29 |

_{g}, geometric diameter; Φ, sphericity; weight; V, actual volume; SA

_{sp}, spherical surface area; PA

_{L}, projected area perpendicular to major axis; PA

_{T}, projected area perpendicular to medium axis; PA

_{W}, projected area perpendicular to minor axis; CPA, criteria projected area. Different letters in a row indicate statistically significant differences at p < 0.001. Means that do not share a letter are significantly different. Tukey’s test was applied with 95% confidence intervals.

Dependent Parameter | Independent Parameter | Model Equation | Maturity Levels | Regression Constant | Statistical Parameters | The Best Fitted Model | |||
---|---|---|---|---|---|---|---|---|---|

a | b | c | R^{2} | SEE | |||||

M (g) | L (mm) | Linear | Immature | 0.021 | 0.016 | - | 0.828 | 0.003 | Quadratic |

Mature | 0.058 | 0.013 | - | 0.949 | 0.001 | ||||

Ripe | −0.056 | 0.036 | - | 0.894 | 0.014 | ||||

M (g) | L (mm) | Quadratic | Immature | 0.130 | −0.031 | 0.005 | 0.852 | 0.003 | |

Mature | −0.013 | 0.037 | −0.002 | 0.952 | 0.001 | ||||

Ripe | 0.351 | −0.107 | 0.012 | 0.980 | 0.007 | ||||

M (g) | L (mm) | S-curve | Immature | 0.168 | −0.338 | - | 0.781 | 0.004 | |

Mature | 0.218 | −0.478 | - | 0.951 | 0.001 | ||||

Ripe | 0.345 | −1.085 | - | 0.796 | 0.020 | ||||

M (g) | L (mm) | Power | Immature | 0.028 | 0.786 | - | 0.824 | 0.003 | |

Mature | 0.049 | 0.580 | - | 0.950 | 0.001 | ||||

Ripe | 0.012 | 1.432 | - | 0.911 | 0.013 | ||||

M (g) | T (mm) | Linear | Immature | 0.033 | 0.012 | - | 0.862 | 0.003 | Quadratic |

Mature | 0.076 | 0.009 | - | 0.903 | 0.002 | ||||

Ripe | −0.052 | 0.035 | - | 0.795 | 0.020 | ||||

M (g) | T (mm) | Quadratic | Immature | 0.239 | −0.071 | 0.008 | 0.925 | 0.002 | |

Mature | 0.286 | −0.057 | 0.005 | 0.952 | 0.001 | ||||

Ripe | 0.419 | −0.133 | 0.015 | 0.883 | 0.017 | ||||

M (g) | T (mm) | S-curve | Immature | 0.155 | −0.296 | - | 0.821 | 0.003 | |

Mature | 0.194 | −0.370 | - | 0.871 | 0.002 | ||||

Ripe | 0.334 | −1.032 | - | 0.711 | 0.024 | ||||

M (g) | T (mm) | Power | Immature | 0.033 | 0.653 | - | 0.856 | 0.003 | |

Mature | 0.060 | 0.439 | - | 0.895 | 0.002 | ||||

Ripe | 0.012 | 1.419 | - | 0.809 | 0.019 | ||||

M (g) | W (mm) | Linear | Immature | 0.012 | 0.018 | - | 0.794 | 0.003 | Quadratic |

Mature | 0.062 | 0.012 | - | 0.927 | 0.001 | ||||

Ripe | −0.065 | 0.038 | - | 0.807 | 0.020 | ||||

M (g) | W (mm) | Quadratic | Immature | 0.306 | −0.110 | 0.014 | 0.895 | 0.003 | |

Mature | 0.260 | −0.053 | 0.005 | 0.960 | 0.001 | ||||

Ripe | 0.557 | −0.186 | 0.020 | 0.926 | 0.014 | ||||

M (g) | W (mm) | S-curve | Immature | 0.172 | −0.357 | - | 0.730 | 0.004 | |

Mature | 0.208 | −0.436 | - | 0.895 | 0.002 | ||||

Ripe | 0.346 | −1.094 | - | 0.722 | 0.023 | ||||

M (g) | W (mm) | Power | Immature | 0.024 | 0.882 | - | 0.790 | 0.003 | |

Mature | 0.051 | 0.543 | - | 0.920 | 0.001 | ||||

Ripe | 0.010 | 1.523 | - | 0.826 | 0.019 | ||||

M (g) | D_{g} (mm) | Linear | Immature | 0.016 | 0.017 | - | 0.878 | 0.003 | Quadratic |

Mature | 0.063 | 0.012 | - | 0.945 | 0.001 | ||||

Ripe | −0.065 | 0.037 | - | 0.821 | 0.019 | ||||

M (g) | D_{g} (mm) | Quadratic | Immature | 0.225 | −0.071 | 0.009 | 0.938 | 0.002 | |

Mature | 0.196 | −0.032 | 0.004 | 0.960 | 0.001 | ||||

Ripe | 0.479 | −0.152 | 0.016 | 0.886 | 0.017 | ||||

M (g) | D_{g} (mm) | S-curve | Immature | 0.171 | −0.360 | - | 0.822 | 0.003 | |

Mature | 0.209 | −0.445 | - | 0.922 | 0.001 | ||||

Ripe | 0.361 | −1.195 | - | 0.767 | 0.021 | ||||

M (g) | D_{g} (mm) | Power | Immature | 0.026 | 0.840 | - | 0.874 | 0.003 | |

Mature | 0.051 | 0.541 | - | 0.940 | 0.001 | ||||

Ripe | 0.011 | 1.474 | - | 0.832 | 0.018 |

_{g}, geometric diameter; R

^{2}, coefficient of determination; SEE, standard error of estimate; a, b, c, constants of curve fittings.

Dependent Parameter | Independent Parameter | Model Equation | Maturity Levels | Regression Constant | Statistical Parameters | The Best Fitted Model | |||
---|---|---|---|---|---|---|---|---|---|

a | b | c | R^{2} | SEE | |||||

M (g) | V (mm^{3}) | Linear | Immature | 0.108 | −0.015 | - | 0.636 | 0.005 | Quadratic |

Mature | 0.049 | 0.001 | - | 0.806 | 0.002 | ||||

Ripe | −0.095 | 0.002 | - | 0.816 | 0.027 | ||||

M (g) | V (mm^{3}) | Quadratic | Immature | 0.125 | −0.190 | 0.163 | 0.925 | 0.002 | |

Mature | 0.795 | −0.012 | 5.164 $\times $ 10^{−5} | 0.988 | 0.001 | ||||

Ripe | 0.828 | −0.015 | 7.376 $\times $ 10^{−5} | 0.995 | 0.006 | ||||

M (g) | V (mm^{3}) | S-curve | Immature | 0.092 | 0.002 | - | 0.692 | 0.004 | |

Mature | 0.217 | −9.947 | - | 0.762 | 0.002 | ||||

Ripe | 0.375 | −24.784 | - | 0.727 | 0.033 | ||||

M (g) | V (mm^{3}) | Power | Immature | 0.096 | 6.619 $\times $ 10^{−18} | - | 0.000 | 0.008 | |

ture | 0.006 | 0.639 | - | 0.798 | 0.002 | ||||

Ripe | 2.626 $\times $ 10^{−5} | 1.819 | - | 0.849 | 0.024 | ||||

M (g) | SA_{sp} (mm^{2}) | Linear | Immature | 0.055 | 6 $\times $ 10^{−4} | - | 0.899 | 0.002 | Quadratic |

Mature | 0.100 | 3 $\times $ 10^{−4} | - | 0.952 | 0.001 | ||||

Ripe | 0.020 | 0.001 | - | 0.955 | 0.009 | ||||

M (g) | SA_{sp} (mm^{2}) | Quadratic | Immature | 0.097 | −6 $\times $ 10^{−4} | 7.825 $\times $ 10^{−6} | 0.936 | 0.002 | |

Mature | 0.124 | −1 $\times $ 10^{−4} | 1.715 $\times $ 10^{−6} | 0.960 | 0.001 | ||||

Ripe | 0.117 | −0.001 | 7.80 $\times $ 10^{−6} | 0.983 | 0.006 | ||||

M (g) | SA_{sp} (mm^{2}) | S-curve | Immature | 0.132 | −2.596 | - | 0.789 | 0.003 | |

Mature | 0.172 | −4.186 | - | 0.905 | 0.002 | ||||

Ripe | 0.280 | −12.808 | - | 0.827 | 0.018 | ||||

M (g) | SA_{sp} (mm^{2}) | Power | Immature | 0.016 | 0.419 | - | 0.874 | 0.003 | |

Mature | 0.038 | 0.270 | - | 0.940 | 0.001 | ||||

Ripe | 0.002 | 0.885 | - | 0.950 | 0.010 |

_{sp}, spherical surface area; R

^{2}, coefficient of determination; SEE, standard error of estimate; a, b, c, constants of curve fittings.

Dependent Parameter | Independent Parameter | Model Equation | Maturity Levels | Regression Constant | Statistical Parameters | The Best Fitted Model | |||
---|---|---|---|---|---|---|---|---|---|

a | b | c | R^{2} | SEE | |||||

M (g) | PA_{L} (mm^{2}) | Linear | Immature | 0.055 | 0.002 | - | 0.831 | 0.003 | Quadratic |

Mature | 0.098 | 0.001 | - | 0.912 | 0.001 | ||||

Ripe | 0.042 | 0.004 | - | 0.792 | 0.020 | ||||

M (g) | PA_{L} (mm^{2}) | Quadratic | Immature | 0.086 | −0.001 | 1 $\times $ 10^{−4} | 0.856 | 0.003 | |

Mature | 0.111 | 0.001 | 1.466 $\times $ 10^{−5} | 0.913 | 0.002 | ||||

Ripe | 0.158 | −0.005 | 1 $\times $ 10^{−4} | 0.835 | 0.020 | ||||

M (g) | PA_{L} (mm^{2}) | S-curve | Immature | 0.132 | −0.614 | - | 0.729 | 0.004 | |

Mature | 0.175 | −1.063 | - | 0.883 | 0.002 | ||||

Ripe | 0.252 | −2.626 | - | 0.700 | 0.024 | ||||

M (g) | PA_{L} (mm^{2}) | Power | Immature | 0.029 | 0.422 | - | 0.807 | 0.003 | |

Mature | 0.054 | 0.280 | - | 0.906 | 0.002 | ||||

Ripe | 0.013 | 0.723 | - | 0.782 | 0.021 | ||||

M (g) | PA_{T} (mm^{2}) | Linear | Immature | 0.055 | 0.002 | - | 0.887 | 0.003 | Quadratic |

Mature | 0.102 | 0.001 | - | 0.941 | 0.001 | ||||

Ripe | 0.040 | 0.004 | - | 0.810 | 0.019 | ||||

M (g) | PA_{T} (mm^{2}) | Quadratic | Immature | 0.114 | −0.004 | 2 $\times $ 10^{−4} | 0.946 | 0.002 | |

Mature | 0.146 | −0.002 | 4.808 $\times $ 10^{−5} | 0.971 | 0.001 | ||||

Ripe | 0.199 | −0.009 | 2 $\times $ 10^{−4} | 0.930 | 0.013 | ||||

M (g) | PA_{T} (mm^{2}) | S-curve | Immature | 0.131 | −0.647 | - | 0.783 | 0.004 | |

Mature | 0.169 | −0.980 | - | 0.874 | 0.001 | ||||

Ripe | 0.239 | −2.167 | - | 0.642 | 0.027 | ||||

M (g) | PA_{T} (mm^{2}) | Power | Immature | 0.029 | 0.412 | - | 0.860 | 0.003 | |

Mature | 0.058 | 0.250 | - | 0.921 | 0.001 | ||||

Ripe | 0.013 | 0.741 | - | 0.790 | 0.020 | ||||

M (g) | PA_{W} (mm^{2}) | Linear | Immature | 0.052 | 0.003 | - | 0.820 | 0.003 | Quadratic |

Mature | 0.099 | 0.001 | - | 0.934 | 0.001 | ||||

Ripe | 0.039 | 0.004 | - | 0.815 | 0.019 | ||||

M (g) | PA_{W} (mm^{2}) | Quadratic | Immature | 0.112 | −0.005 | 2 $\times $ 10^{−4} | 0.888 | 0.003 | |

Mature | 0.139 | −0.002 | 4.768 $\times $ 10^{−5} | 0.955 | 0.001 | ||||

Ripe | 0.207 | −0.010 | 3 $\times $ 10^{−4} | 0.942 | 0.012 | ||||

M (g) | PA_{W} (mm^{2}) | S-curve | Immature | 0.132 | −0.619 | - | 0.695 | 0.004 | |

Mature | 0.172 | −1.011 | - | 0.872 | 0.002 | ||||

Ripe | 0.240 | −2.168 | - | 0.652 | 0.026 | ||||

M (g) | PA_{W} (mm^{2}) | Power | Immature | 0.027 | 0.441 | - | 0.790 | 0.003 | |

Mature | 0.055 | 0.271 | - | 0.916 | 0.001 | ||||

Ripe | 0.013 | 0.744 | - | 0.795 | 0.020 | ||||

M (g) | CPA | Linear | Immature | 0.054 | 0.002 | - | 0.832 | 0.003 | Quadratic |

Mature | 0.099 | 0.001 | - | 0.950 | 0.001 | ||||

Ripe | 0.034 | 0.004 | - | 0.833 | 0.018 | ||||

M (g) | CPA | Quadratic | Immature | 0.102 | −0.003 | 2 $\times $ 10^{−4} | 0.880 | 0.003 | |

Mature | 0.130 | −0.001 | 3.55 $\times $ 10^{−5} | 0.962 | 0.001 | ||||

Ripe | 0.221 | −0.011 | 3 $\times $ 10^{−4} | 0.966 | 0.009 | ||||

M (g) | CPA | S-curve | Immature | 0.132 | −0.632 | - | 0.716 | 0.004 | |

Mature | 0.172 | −1.037 | - | 0.896 | 0.002 | ||||

Ripe | 0.250 | −2.445 | - | 0.683 | 0.025 | ||||

M (g) | CPA | Power | Immature | 0.028 | 0.431 | - | 0.805 | 0.003 | |

Mature | 0.055 | 0.272 | - | 0.935 | 0.001 | ||||

Ripe | 0.011 | 0.784 | - | 0.816 | 0.019 |

_{L}, projected area perpendicular to major axis; PA

_{T}, projected area perpendicular to medium axis; PA

_{W}, projected area perpendicular to minor axis; CPA, criteria projected area; R

^{2}, coefficient of determination; SEE, standard error of estimate; a, b, c, constants of curve fittings.

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## Share and Cite

**MDPI and ACS Style**

Megat Ahmad Azman, P.N.; Shamsudin, R.; Che Man, H.; Ya’acob, M.E.
Some Physical Properties and Mass Modelling of Pepper Berries (*Piper nigrum* L.), Variety Kuching, at Different Maturity Levels. *Processes* **2020**, *8*, 1314.
https://doi.org/10.3390/pr8101314

**AMA Style**

Megat Ahmad Azman PN, Shamsudin R, Che Man H, Ya’acob ME.
Some Physical Properties and Mass Modelling of Pepper Berries (*Piper nigrum* L.), Variety Kuching, at Different Maturity Levels. *Processes*. 2020; 8(10):1314.
https://doi.org/10.3390/pr8101314

**Chicago/Turabian Style**

Megat Ahmad Azman, Puteri Nurain, Rosnah Shamsudin, Hasfalina Che Man, and Mohammad Effendy Ya’acob.
2020. "Some Physical Properties and Mass Modelling of Pepper Berries (*Piper nigrum* L.), Variety Kuching, at Different Maturity Levels" *Processes* 8, no. 10: 1314.
https://doi.org/10.3390/pr8101314