高壓加工及酵素滲透處理於蘋果軟化之探討

Abstract

近年來，臺灣高齡人口快速增長，在 2018 年 3 月高齡人口比例超過 14%，正式進入高齡社會，高齡消費者市場也快速擴大，在飲食方面，因年歲增長造成的咀嚼吞嚥障礙常使高齡者有進食上的困難，可能導致其營養不均及飲食限制造成心理的負擔，因此開發適口性佳且色香味俱全之食品為高齡食品開發目標，而本研究選擇廣受歡迎之硬脆蘋果作為材料，進行新高齡食品製程之開發，欲以全程非熱加工方式軟化堅硬蔬果以達到日本介護食品協議會通用食品 UDF 範圍，並同時保留其外觀及營養成分。本研究分為二部分，第一部分 (製程A) 首先以減壓方式促進複合果膠酶液進入蘋果切片並進行軟化反應，再對其施以高壓處理降低酵素活性及殺菌，製程A最終調整之條件為加入切片量 1/3 之 0.05% 複合果膠酶液體，再以真空包裝機減壓處理 40 秒後封口，於 4˚C 下反應 1 小時，接著施以 600 MPa 10 分鐘之高壓處理，產品可成功達 UDF「容易咀嚼」等級，此製程產品適合於 -20˚C 冷凍保存以抑制軟化反應，在品質測定方面，以600 MPa持壓10分鐘進行高壓處理後L*值顯著高於對照組、a*值顯著低對照組，表示其能夠降低切片褐變現象，還原糖、維生素C、總酚、總類黃酮含量分別為對照組之91.71%、134.44%、132.64% 及119.36%，DPPH抗氧化能力為對照組之169.35%，顯示其除了能避免成分流失，亦具有增加成分釋放之效果，衛生檢驗方面則能有效抑制微生物生長且大腸桿菌群篩檢為陰性。由於製程 A 使用之酵素為複方，有較難控制之缺點，因此第二部份針對其缺點加以調整 (製程B)，嘗試以單一果膠酶進行製程開發，首先分別測定聚半乳糖醛酸酶與果膠裂解酶於不同溫度下活性，以及熱與高壓處理對其活性影響，再依其特性搭配第一部份結果進行製程改良。從酵素測定結果可知 200 MPa可提升果膠裂解酶之活性，而製程B最終調整條件為加入切片量 1/3 之 0.01% 果膠裂解酶液體，再以真空包裝機減壓處理 40 秒後封口，接著施以200 MPa 10 分鐘高壓處理促進酵素反應，並於 50˚C 下反應 30 分鐘，最後以 600 MPa 3 分鐘之高壓處理進行殺菌，此產品可成功達 UDF「容易咀嚼」等級，在4˚C 冷藏保存過程中能夠抑制軟化反應避免硬度繼續下降，且衛生檢驗方面7天內能有效抑制微生物生長，大腸桿菌群篩檢亦皆為陰性。本研究開發之新製程為全程非熱，不但能保留其外觀及營養，生產需時短且能提供即食，具有發展新高齡食品之潛力。

In recent years, Taiwan's elderly population has grown rapidly. In March 2018, the proportion of the elderly population exceeded 14%. It officially entered the aged society, and the market for senior consumers has also expanded rapidly. In terms of diet, chewing and swallowing disorders caused by age often appear on elderly. The difficulty in eating may lead to psychological burdens caused by uneven nutrition and dietary restrictions. Therefore, the development of foods with mouth comfort, color and flavor is the goal of advanced food development, and this study chooses the popular hard and crisp apples to be the material. The object of the study is to develop the new elderly food process and to soften the hard fruits and vegetables by the new process without thermal treatment, and the product will achieve UDF. At the same time, it will maintain its appearance and nutrients. This study is divided into two parts. The first part (Process A) firstly promotes commercial complex pectinase solution into apple slices by decompression and softens the material, and then applies high pressure processing to reduce enzyme activity and sterilization. Process A is finally adjusted. The condition is to add 0.05% of commercial complex pectinase solution in the amount of 1/3 slices , and then pack with vacuum-packing machine after depressure for 40 seconds, react at 4 ̊C for 1 hour, then applying 600 MPa for 10 minutes. The product can successfully reach the UDF 'easy chewing' grade. This process is suitable for -20 ̊C freezing to inhibit the softening reaction. In terms of quality measurement, the L* value is significantly higher after high pressure processing at 600 MPa for 10 minutes. In the control group, the a* value was significantly lower in the control group, indicating that it could reduce the browning of the apple slices. The contents of reducing sugar, vitamin C, total phenol and total flavonoids were 91.71%, 134.44%, 132.64% and 119.36% of the control group, respectively. The DPPH antioxidant capacity was 169.35% of the control group, which showed that it not only avoided the loss of components, but also increased the release of the components. The hygienic test can effectively inhibit the growth of microorganisms and the Coliform. The test of Coliform was negative. Since the enzyme used in Process A is a complicated, it has the disadvantage of being difficult to control. Therefore, the second part adjusts the shortages of process A (Process B), and attempts to develop the process with a single pectinase. First, the polygalacturonase and pectin lyase are separately determined, including the activity at different temperatures, as well as the effect of heat and high pressure treatment on their activity, then develop the method based on the first part of the results and the characteristics of single enzymes. According to the results of enzyme assay, it can be known that 200 MPa can enhance the activity of pectin lyase. The final condition of Process B is to add 0.01% of the pectin lyase solution in the amount of 1/3 of the slices, and then pack with vacuum-packing machine after depressure for 40 seconds, then seal it, and then apply 200 MPa for 10 minutes to promote the enzyme reaction. It is reacted at 50 ̊C for 30 minutes, and finally sterilized by high pressure processing at 600 MPa for 3 minutes. This product can successfully reach the UDF “easy chewable” grade, and can inhibit the softening reaction during 4 ̊C storage to avoid the hardness decreasing. And the hygienic test can effectively inhibit the growth of microorganisms within 7 days, and the test for Coliform is also negative. The new process developed in this study is non-thermal through the process, not only retains its appearance and nutrition, but also takes short production time and provides ready-to-eat food. It has the potential to develop new elderly foods.