A rapid extraction and content determination method for edible sweet potato lignified fibers

Abstract

This invention provides a rapid extraction and content determination method for lignified fibers from edible sweet potatoes. The method primarily involves high-pressure steaming of sweet potato tubers, followed by physical methods such as passing the tubers through an 80-mesh nylon mesh bag to remove the fine flesh, thus obtaining lignified fibers. Preliminary decolorization and removal of proteins and sugars are then performed using alcohol and NaOH to prepare a primary lignified fiber sample, which can provide material for further material analysis. This method achieves rapid extraction and identification of lignified fibers from the underground tubers of edible sweet potatoes, filling a technical gap in the quantitative determination of lignified fibers, and providing a technical solution for material preparation for further scientific research.

Description

Technical Field

[0001] This invention relates to a food processing method, specifically a method for the rapid extraction and content determination of lignified fibers from edible sweet potatoes, belonging to the field of food processing technology. Background Technology

[0002] Currently, the extraction and processing of sweet potato residue refers to the processed products left after starch extraction from sweet potatoes. This includes substances from the sweet potato tuber other than the main sweet potato starch and some water-soluble substances, which differs from the lignified fibers in the sweet potato tuber that this invention aims to extract. Edible sweet potatoes contain fibrous substances in their tubers after steaming or boiling, which significantly impacts their edibility and is a crucial indicator of the quality of edible sweet potato varieties. However, there is currently no technology for extracting lignified fibers from sweet potato tubers; the quantity of these fibrous substances is only assessed through sensory evaluation after tasting. Unlike lignified fibers, dietary fiber is divided into insoluble and soluble dietary fiber. Insoluble dietary fiber is a component of cell walls, while soluble dietary fiber mainly comes from hemicellulose and intracellular and intercellular components such as pectin and some viscous soluble polysaccharides. To address these issues, we propose a rapid method for extracting lignified fibers from edible sweet potato tubers. This method aims to quantify the amount of lignified fibers in sweet potato tubers to evaluate their quality. It also provides breeding units with an important identification technique for breeding high-quality sweet potatoes with reduced lignified fibers. Summary of the Invention

[0003] The purpose of this invention is to provide a rapid extraction and content determination method for edible sweet potato lignified fibers.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A rapid extraction and content determination method for lignified fibers from edible sweet potatoes, comprising the following steps:

[0006] (1) Raw material selection: Select whole, undamaged, and disease-free edible sweet potato underground tubers as raw materials;

[0007] (2) Cleaning: Wash the edible sweet potato underground tubers from step (1) with clean water to remove the mud and sand from the surface and wipe the surface dry;

[0008] (3) Cutting and weighing: Cut the edible sweet potato underground tubers cleaned in step (2) into two halves, take one half and weigh it with a balance, record it as W1, and the unit is g;

[0009] (4) High-pressure cooking: High-pressure cooking of the potato chunks weighed in step (3) for 20-30 minutes;

[0010] (5) Filtering the potato flesh: Peel the potato pieces after high-pressure cooking in step (4), and put the peeled potato pieces into a food-grade 80-mesh nylon mesh bag. Squeeze hard to squeeze out the potato flesh from the mesh bag. When 95% of the total volume of potato flesh is squeezed out, place the nylon mesh bag under running water and wash and rub continuously until no visible potato flesh is washed out of the mesh bag. Then take out the remaining substances in the mesh bag, drain the water, and you will get edible sweet potato lignified fibers. Weigh the mass using a balance and record it as W2, with the unit being g.

[0011] (6) Determination of fresh weight content of lignified fibers: Fresh weight crude content of lignified fibers (%) = W2 / W1×100;

[0012] (7) Determination of dry weight content of lignified fibrous fibers: Cut the remaining half of the edible sweet potato underground tubers from step (2) into thin strips. Take 50g of potato strips and the lignified fibrous fibers from step (5) and dry them at 100℃ to constant weight. Weigh the dried potato strips with a balance and record the weight as W3 in g. Weigh the dried lignified fibrous fibers with a balance and record the weight as W4 in g. The dry weight of the potato tubers (Dw%) = W3 / 50×100. The dry weight crude content of lignified fibrous fibers (%) = W4 / (W1×Dw%)×100.

[0013] (8) Removing impurities: Immerse the lignified fibrous strands obtained in step (5) in 75% alcohol for 10 minutes, rinse with water 3 times for 5-10 minutes each time, then immerse the rinsed lignified fibrous strands in 1% NaOH solution for 300 minutes, rinse with water 3 times for 5-10 minutes each time, drain the water, and dry at 60-80℃ to constant weight to obtain edible sweet potato lignified fibrous strands after removing impurities.

[0014] The conditions for high-pressure cooking are a pressure of 80~100 MPa and a temperature of 100℃.

[0015] The significant advantages of this invention are:

[0016] Lignified fibers significantly impact the edible quality of sweet potatoes and are a crucial indicator of the variety's quality. However, currently, there is no technology for extracting lignified fibers from the underground tubers of edible sweet potatoes, and the quantity of these fibrous substances is only assessed through sensory evaluation after tasting. Therefore, this invention proposes a simple and rapid method for extracting and determining the content of lignified fibers from edible sweet potato tubers. The method primarily involves steaming the tubers and then using a physical method—passing them through an 80-mesh nylon mesh bag—to remove the fine flesh, obtaining the lignified fibers. Preliminary decolorization and removal of proteins and sugars are then performed using alcohol and NaOH to prepare a primary lignified fiber sample, providing material for further material analysis. This method achieves rapid extraction and identification of lignified fibers from the underground tubers of edible sweet potatoes, filling the technological gap in the quantitative determination of lignified fibers and providing a technical solution for material preparation for further scientific research. Attached Figure Description

[0017] Figure 1 : The extracted lignified fibers from sweet potato. From left to right, the tested varieties are Pushu 32, Fushu 806, and Fushu 737.

[0018] Figure 2 Comparison of lignified fiber content in underground tubers of different sweet potato varieties. Detailed Implementation

[0019] To make the content of this invention easier to understand, the technical solution of this invention will be further described below with reference to specific embodiments, but this invention is not limited thereto.

[0020] Example 1

[0021] A rapid extraction and content determination method for lignified fibers from edible sweet potatoes, comprising the following steps:

[0022] (1) Raw material selection: Select whole, undamaged, disease-free, and pest-free edible sweet potato underground tubers weighing approximately 250g as raw materials;

[0023] (2) Cleaning: Wash the edible sweet potato underground tubers from step (1) with clean water to remove the mud and sand from the surface and wipe the surface dry;

[0024] (3) Cutting and weighing: Cut the edible sweet potato underground tubers cleaned in step (2) into two halves, take one half and weigh it with a balance, record it as W1, and the unit is g;

[0025] (4) High-pressure cooking: Place the weighed potato pieces from step (3) into a pressure cooker for cooking. Set the temperature to 100℃, the time to 8~15min, and the pressure to 80~100MPa.

[0026] (5) Filtering the potato flesh: Peel the potato pieces after high-pressure cooking in step (4), and put the peeled potato pieces into a food-grade 80-mesh nylon mesh bag. Squeeze hard to squeeze out the potato flesh from the mesh bag. When 95% of the total volume of potato flesh is squeezed out, place the nylon mesh bag under running water and wash and rub continuously until no visible potato flesh is washed out of the mesh bag. Then take out the remaining substances in the mesh bag, drain the water, and you will get edible sweet potato lignified fibers. Weigh the mass using a balance and record it as W2, with the unit being g.

[0027] (6) Determination of fresh weight content of lignified fibers: Fresh weight crude content of lignified fibers (%) = W2 / W1×100;

[0028] (7) Determination of dry weight content of lignified fibrous strands: Cut the remaining half of the edible sweet potato underground tubers from step (2) into thin strips with a diameter of less than 0.5 cm. Take 50 g of the strips and dry them at 100°C until constant weight. Weigh the dried strips using a balance and record the weight as W3 in g. Dry the lignified fibrous strands from step (5) at 100°C until constant weight. Weigh the dried lignified fibrous strands using a balance and record the weight as W4 in g. Dry weight of sweet potato tubers (Dw%) = W3 / 50 × 100, dry weight crude content of lignified fibrous strands (%) = W4 / (W1 × Dw%) × 100.

[0029] (8) Removing impurities: Immerse the lignified fibrous strands obtained in step (5) in 75% alcohol for 10 minutes, rinse with running water 3 times for 5-10 minutes each time, then immerse the rinsed lignified fibrous strands in 1% NaOH solution for 300 minutes, rinse with running water 3 times for 5-10 minutes each time, drain the water and dry at 60°C to constant weight to obtain edible sweet potato lignified fibrous strands after removing impurities.

[0030] Example 2

[0031] Using Pushu 32, Fushu 34, Fushu 806, and Fushu 737 as test varieties, edible sweet potato lignified fibers were extracted according to the method provided in Example 1. Figure 1 The content was determined, and the high-pressure cooking temperature was set at 100℃, the time at 10 min, and the pressure at 100 MPa. The results are shown in the table below.

[0032] Table 1. Content of lignified fibers in different sweet potato varieties

[0033]

[0034] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. A rapid extraction and content determination method for edible sweet potato lignified fibers, characterized in that: Includes the following steps: (1) Raw material selection: Select whole, undamaged, and disease-free edible sweet potato underground tubers as raw materials; (2) Cleaning: Wash the edible sweet potato underground tubers from step (1) with clean water to remove the mud and sand from the surface and wipe the surface dry; (3) Cutting and weighing: Cut the edible sweet potato underground tubers cleaned in step (2) into two halves, take one half and weigh it with a balance, record it as W1, and the unit is g; (4) High-pressure cooking: High-pressure cooking of the potato chunks weighed in step (3) for 20-30 minutes; (5) Filtering the potato flesh: Peel the potato pieces after high-pressure cooking in step (4), and put the peeled potato pieces into a food-grade 80-mesh nylon mesh bag. Squeeze hard to squeeze out the potato flesh from the mesh bag. When 95% of the total volume of potato flesh is squeezed out, place the nylon mesh bag under running water and wash and rub continuously until no visible potato flesh is washed out of the mesh bag. Then take out the remaining substances in the mesh bag, drain the water, and you will get edible sweet potato lignified fibers. Weigh the mass using a balance and record it as W2, with the unit being g. (6) Determination of fresh weight content of lignified fibers: Fresh weight crude content of lignified fibers (%) = W2 / W1×100; (7) Determination of dry weight content of lignified fibrous fibers: Cut the remaining half of the edible sweet potato underground tubers from step (2) into thin strips. Take 50g of potato strips and the lignified fibrous fibers from step (5) and dry them at 100℃ to constant weight. Weigh the dried potato strips with a balance and record the weight as W3 in g. Weigh the dried lignified fibrous fibers with a balance and record the weight as W4 in g. The dry weight of the potato tubers (Dw%) = W3 / 50×100. The dry weight crude content of lignified fibrous fibers (%) = W4 / (W1×Dw%)×100. (8) Removing impurities: Immerse the lignified fibrous strands obtained in step (5) in 75% alcohol for 10 minutes, rinse with water 3 times for 5-10 minutes each time, then immerse the rinsed lignified fibrous strands in 1% NaOH solution for 300 minutes, rinse with water 3 times for 5-10 minutes each time, drain the water, and dry at 60-80℃ to constant weight to obtain edible sweet potato lignified fibrous strands after removing impurities.

2. The method for rapid extraction and content determination of edible sweet potato lignified fibers according to claim 1, characterized in that: The conditions for high-pressure cooking are a pressure of 80~100 MPa and a temperature of 100℃.

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